Performance, Carcass Traits, and Meat Fatty Acid Profile of Post-Weaning and Finishing Zebu Steers on Tropical Pasture with Three Low-Intake Supplementation Strategies
by
, , , , , , , , , , , and
Diana Carolina Cediel-Devia
1
,
Luís Henrique Schaitz
1,
Fabiano Ferreira da Silva
1,
Laize Vieira Santos
1,
Ana Paula Gomes da Silva
1,
Marceliana da Conceição Santos
1,
Wbeimar Yamit Sanchez Dueñez
1,
Osman Ronaldo Aguilar Melgar
1,
Tarcísio Ribeiro Paixão
1,
João Wilian Dias Silva
1,
Thiago Luís Alves Campos de Araújo
2,
Dorgival Morais de Lima Júnior
2,* and
Robério Rodrigues Silva
1
1
Department of Rural and Animal Technology, Southwest Bahia State University, Primavera Square, Itapetinga 45700-000, BA, Brazil
2
Department of Animal Science, Federal University of the Semi-Arid Region, Francisco Mota Street, Costa e Silva, Mossoró 59625-900, RN, Brazil
*
Author to whom correspondence should be addressed.
Animals 2024, 14(17), 2486; https://doi.org/10.3390/ani14172486
Submission received: 16 May 2024
/
Revised: 21 June 2024
/
Accepted: 29 June 2024
/
Published: 27 August 2024
(This article belongs to the Section Animal Nutrition)
Abstract
:Simple Summary
Protein and energy supplementation increases the performance of pasture-finished cattle. Three low-intake supplementation strategies (restricted, low, and moderate) were tested during the post-weaning and finishing steers on pasture for 310 days. The moderate supplementation strategy (use of 1 g/kg and 2 g/kg of body weight of concentrated supplementation during the rainy and dry seasons, respectively) increased the weight and fat content of the steers’ carcass and the intramuscular fat of the beef. However, steers consuming the moderate supplementation strategy produced meat with lower levels of omega-3 fatty acids. We recommend the use of 1 g/kg and 2 g/kg of body weight of concentrated supplementation during the rainy and dry seasons, respectively, in the post-weaning and finishing steers on tropical pastures.
Abstract
The study aimed to evaluate the effects of three supplementation strategies on intake, apparent digestibility, feeding behavior, performance, carcass traits, proximate composition, and the fatty acid profile of meat from steers on tropical pasture during the post-weaning and finishing stages. The experiment involved 33 1/2 Holstein × 1/2 castrated Zebu steers weighing 335 ± 42.90 kg, aged 22 ± 2 m. The animals were managed on Urochloa brizantha cv. Marandu using an intermittent grazing system with continuous stocking and variable stocking rates for 310 days. The supplementation strategies were as follows: MS/US (mineral salt/urea supplementation): mineral salt in the rainy season and mineral salt with urea in the dry season; US/PS1 (urea supplementation/protein supplementation): mineral salt with urea in the rainy season and protein supplement at 1 g/kg body weight (BW) in the dry season; and PS1/PS2 (protein supplementation 1/protein supplementation 2): protein supplement at 1 g/kg BW in the rainy season and 2 g/kg BW in the dry season. The dry matter intake did not differ significantly (p > 0.05) between strategies. However, the post-weaning PS1/PS2 strategy resulted in higher (p < 0.05) crude protein intake. The final body weight did not differ (p > 0.05) between the strategies, but the average daily gain in post-weaning and finishing was higher (p < 0.05) for MS/US (restricted) animals. Carcass weight, subcutaneous fat thickness, and lipid content in meat were significantly higher (p < 0.05) for steers in the PS1/PS2 group. Steers finished on MS/US produced meat with a higher content of polyunsaturated fatty acids and ω-3 fatty acids (p < 0.05). Concentrate supplementation at 1 g/kg BW during the rainy season and 2 g/kg BW during the dry season is recommended for post-weaning and finishing steers on tropical pasture.
1. Introduction
Beef cattle production under grazing conditions is significantly influenced by seasonal variations in light, rainfall, and temperature [1]. These factors directly impact the chemical composition and availability of forage in the pasture, affecting the performance of grazing cattle [2]. In tropical regions near the equator, seasonal variations are more pronounced, typically divided into rainy and dry seasons [3]. During the dry season, pasture quality and availability decline, leading to a significant loss in nutritional value [4]. This is particularly true for protein, which is essential for fiber fermentation in the rumen of forage-fed animals [5].
Supplementing cattle on pasture is a well-established feed security strategy that aims to maximize forage utilization throughout the year, thereby enhancing the performance of post-weaning and finishing animals on pasture. Given the seasonal variations in forage chemical composition, post-weaning and finishing supplementation strategies must be adjusted accordingly [6]. This differentiation particularly applies to the type of nitrogen used (e.g., non-protein nitrogen, true protein, and rumen-undegradable protein) and the energy source (e.g., non-fibrous carbohydrates, fibrous carbohydrates, and sugars).
Rocha et al. [7] investigated two supplementation strategies during the post-weaning period for steers on tropical pasture: mineral supplementation during the rainy season with the protein concentrate at 1 g/kg body weight (BW) during the dry season, and the protein concentrate at 1 g/kg BW during the rainy season with 2 g/kg BW during the dry season. They found similar results in animal performance and feed conversion at the end of the post-weaning phase. Likewise, Ramos et al. [8] found that supplementing steers with protein concentrate during at least one season (either dry or rainy) produced a carcass and meat quality similar to the quality of those supplemented during both seasons.
Furthermore, there is a consensus that protein or protein–energy supplementation for steers during the post-weaning phase has a positive residual effect on performance and carcass and meat characteristics during the finishing phase. [9,10,11,12] reported higher ω-3 deposition and a lower ω-6:ω-3 ratio in the meat of steers finished with a mineral mixture only, compared to those supplemented with protein concentrate.
However, studies comparing strategies that use protein supplementation from non-protein nitrogen sources (such as mineral salt with urea) versus lower levels of protein–energy supplementation for post-weaning and finishing cattle on pasture are limited. Their impact on performance, carcass characteristics, and meat fatty acid profile remains an area for further research.
Our hypothesis was that a moderate adjustment in the supplementation of steers, with a nutritional strategy of 1 g/kg BW during the rainy season and 2 g/kg BW during the dry season, during the post-weaning and finishing phases, could lead to improved performance, carcass traits, and meat quality compared to a low-supplementation approach (mineral salt with urea during the rainy season and protein concentrate at 1 g/kg BW during the dry season) and a restricted approach (mineral salt during the rainy season and mineral salt with urea during the dry season).
Therefore, this study aimed to evaluate the impact of three supplementation strategies on intake, apparent digestibility, feeding behavior, performance, carcass traits, proximate composition, and fatty acid composition in meat from post-weaning and finishing steers on tropical pasture.
2. Materials and Methods
2.1. Animals, Treatments, and Design
The experiment was conducted in Ribeirão do Largo, Bahia, located at co-ordinates 15°26′46″ S and 40°44′24″ W, at an altitude of 800 m, with a Koppen Aw climate classification. The study duration was 310 days.
A total of 33 crossbred steers (1/2 Holstein × 1/2 Zebu) with an initial average weight of 335 ± 42.90 kg and an average age of 22 ± 2 months were used. At the beginning of the study, the animals were dewormed with Ivermectin (IVOMEC®, Merial, Cuiabá, Brazil) and immunologically castrated (BOPRIVA®, Pfizer, New York, NY, USA). The steers were divided into three groups of 11, with each group receiving a different supplementation strategy in a completely randomized design (Table 1).
The supplementation strategies were as follows: Restricted: mineral salt during the rainy season and mineral salt with urea during the dry season; Low: mineral salt with urea during the rainy season and protein concentrate at 1 g/kg BW during the dry season; and Moderate: protein concentrate at 1 g/kg BW during the rainy season and 2 g/kg BW during the dry season. The concentrate supplement was formulated according to the National Research Council [13] guidelines, with a target average daily gain of 0.6 kg/day (Table 2 and Table 3). It was provided daily at 10h00 in uncovered plastic troughs accessible from both sides, with a linear sizing of 80 cm per animal. Drinking water was available ad libitum from 500 L automatic drinkers in all paddocks.
2.2. Grazing Method and Forage Characteristics
The animals were managed in an intermittent grazing system with continuous stocking and a variable stocking rate. The total grazing area covered 11.85 ha of Urochloa brizantha cv. Marandu. To minimize possible discrepancies between paddocks that could impact animal performance, the experimental area was divided into three modules. Modules A and B comprised 14 paddocks, each half a hectare, while module C had five paddocks of approximately one hectare each. The experimental design was managed to provide a 35-day rest period for each paddock. To achieve this, the animals stayed in each paddock for five days in modules A and B, and for seven days in module C, resulting in a 35-day evaluation cycle. At the end of each cycle, the animals were rotated between modules to ensure consistent experimental conditions across all groups.
Forage samples were collected at 35-day intervals from the paddocks where animals entered and exited in each module. Forage availability was evaluated using the comparative visual yield method described by Haydock and Shaw [14]. The weight of the fresh forage mass from the square was obtained using a semi-analytical digital scale. Following this, the samples were separated into morphological components (dead material, stem + sheath, and leaf), each of which was weighed to determine its proportion.
Forage intake was estimated using a simulated grazing procedure as described by Johnson [15]. The potentially digestible dry matter content (pdDM) of the forage was calculated using the equation by Detmann et al. [16]:
where NDFap = neutral detergent fiber corrected for ash and protein; and iNDF = indigestible neutral detergent fiber. All components in the equation are expressed in percentage terms.
pdDM = 0.98 [(100 − NDFap) + (NDFap − iNDF)]
Forage allowance (FA) was calculated using the following equation:
where FA = forage allowance (kg BW/ha); FM = forage mass (kg DM/100 kg BW); and SR = average animal load per period (kg BW/ha).
FA = {[((FM entry + FM exit)/2)/SR]/N of days} × 100
2.3. Intake and Apparent Digestibility
Intake and digestibility assessments for dry matter and nutrients were conducted between the 50th and 61st days of the experiment. Fecal output by the animals was estimated using the external marker chromic oxide (Cr2O3) at a dose of 10 g/animal/ day. This marker was administered daily at 06h00 in a single dose for 12 days, delivered in paper cartridges and inserted manually into the oral cavity of each animal. The first seven days were used to stabilize the marker’s excretion flow and to accustom the animals to handling, while the final five days were dedicated to feces collection. Feces were collected at alternating times (08h00, 10h00, 12h00, 14h00, and 16h00) to obtain samples representing the daily gastrointestinal flow.
Feces were collected daily, directly from the rectal ampulla of the animals, labeled, and stored in a freezer at −20 °C. To create a composite sample, 100 g of pre-dried feces were weighed per animal each day, then homogenized for further analysis. Fecal dry matter output was estimated using the INCT-CA M-005/1 method described by Detmann et al. [17]. To calculate fecal output with chromic oxide, the following equation was applied:
where FO = fecal output (g/day).
FO = (Cr2O3 supplied, g/day/Cr2O3 in feces, %) × 100
To estimate individual dry matter intake from the supplement, the external marker titanium dioxide (TiO2) was used at a dose of 15 g/animal/day. The marker was added and thoroughly mixed into the supplement, which was provided daily at 10h00 for 11 days, following the methodology by Titgemeyer et al. [18]. The concentration of titanium in the feces and in the supplement was analyzed using the INCT-CA M-007/1 method described by Detmann et al. [17]. The supplement dry matter intake was calculated using the following equation:
where SDMI = supplement dry matter intake (kg/day); and FE = fecal output (g/day).
SDMI = ((FE × TiO2 in feces, g/day)/TiO2 in supplement, %)
The voluntary roughage intake was estimated using the internal marker iNDF (indigestible neutral detergent fiber), following the methodology of Detmann et al. [17]. This method involves the ruminal incubation of a 0.5 g air-dried sample of feces, concentrate, and forage, ground to a 2 mm particle size. Samples are taken in duplicate and placed in non-woven fabric bags (‘TNT’) with a grammage of 100 g/m² and dimensions of 5 × 5 cm. The ruminal incubation period lasted 288 h. The residual material was subjected to neutral detergent extraction to determine the iNDF content.
The forage dry matter intake was calculated using the following formula:
where FDMI = forage dry matter intake (kg/day); and FO = fecal output (kg DM/day).
FDMI = [(FO × %iNDF in feces) − %Marker in the forage]/%Marker in supplement
The apparent digestibility coefficients (ADC) of nutrients were estimated using the following equation:
where NI = nutrient intake (g/day); and NE = nutrient excretion (g/day).
ADC, g/kg = [(NI − NE)/NI]
2.4. Chemical Composition of Forage, Supplements, and Feces
Samples of forage, concentrate, and feces were pre-dried in a forced-air oven at 55 °C for 72 h, then ground in a Wiley-type mill with a 1 mm sieve. The following analyses were conducted according Detmann et al. [17]: dry matter (DM; INCT method CA G-001/1); mineral matter (MM; INCT method CA M-001/1); crude protein (CP; INCT method CA N-001/1); ether extract (EE; INCT method CA G-004/1); neutral detergent fiber (NDF; INCT method CA F-002/1), with corrections for protein and ash (NDFap; INCT CA N-004/1 and CA M-002/1); acid detergent fiber (ADF; INCT method CA F-004/1), with corrections for protein and ash (ADFap; INCT CA N-005/1 and CA M-003/1); lignin (INCT method CA F-005/1); and indigestible neutral detergent fiber (iNDF, INCT method CA F-009/1). For forage and feces samples, the non-fibrous carbohydrates corrected for ash and protein (NFCap) were determined using the equation proposed by Detmann et al. [17]. The total digestible nutrient (TDN) content in forage and supplements was calculated using the formula from [19].
2.5. Feeding Behavior
Feeding behavior was evaluated by trained observers from the 85th to the 87th day of the experimental period, resulting in 72 continuous hours of data collection. The parameters collected included grazing time, rumination time, time spent at the trough, time spent on other activities, total feeding time, and total chewing time. Activities surrounding rumination, grazing, idling, and feeding at the trough were recorded at 5 min intervals in an ethogram to determine the time expended on each of these activities. Time-series discretization was performed directly in the data collection worksheets, by counting the discrete bouts of feeding, other activities, and rumination (Silva et al. [20]).
Rumination chews were visually assessed by observing rumination activities and counting the number of chews per cud. Observations were made three times in the morning (before the concentrate was provided) and three times in the afternoon for each animal, according to the procedure by Bürger et al. [21]. Additionally, the number of bites and the time (in seconds) spent grazing were measured, with three replicates per animal in the morning and three in the afternoon, according to the methodology described by Baggio et al. [22].
After determining the values for dry matter intake (DMI) and neutral detergent fiber (NDF) intake, the efficiencies for rumination and feeding were calculated using the formulae recommended by Silva et al. [20].
2.6. Performance and Carcass Traits
The average daily gain (ADG) during the experimental period was calculated by weighing the animals at the start and end of the experiment, following a 12 h water/feed fast for both measurements. The ADG was determined by dividing the total weight gained during the period by the number of days elapsed. Intermediate weighing sessions were performed every 35 days to adjust the amount of concentrate supplied, as it is based on the body weight of the animals. Feed conversion was calculated using the values for DM intake and ADG.
The animals were slaughtered at an average age of 33 months, with an average final live weight of 490.4 ± 50.8 kg. Before transportation to the slaughterhouse, they were fasted for 16 h, and then weighed to determine slaughter weight (SW). At this point, ribeye area and backfat thickness were measured using ultrasound with an ultrasound device (CTS-900V, Ultramedic, Boa Vista, Brazil).
After weighing and measurements, the animals were transported to a slaughterhouse-packing plant, where they were slaughtered according to the standard procedure and the flow of the plant, adhering to the guidelines of Normative Instruction no. 3, of 17 January 2000, from the Ministry of Agriculture, Livestock, and Supply. The carcasses were then halved and weighed to determine the hot carcass weight (HCW), labeled, and placed in a cooling chamber for 24 h at around 0 ± 0.5 °C. Hot carcass yield (HCY) was calculated using the following formula:
HCY = (HCW/SW) × 100
2.7. Proximate Composition and Cholesterol Content of Meat
Meat samples, each weighing 0.5 kg, were extracted from the Longissimus thoracis (LT) muscle on the right side of the animals’ cold carcass, specifically between the 12th and 13th ribs. These samples were then divided into two pieces of about 0.25 kg each. They were wrapped in polyethylene film, then in aluminum foil, and finally placed in labeled plastic bags. The labels contained information about the animal, treatment, and type of analysis. The samples were immediately stored at −10 °C until laboratory analyses. After two months, the samples were thawed to measure moisture, ash, and protein content. The ash and protein analyses using method no. 923.03 and no. 920.87, respectively [23]. Total lipid extraction was conducted using a mixture of chloroform, methanol, and water in a ratio of 2:2:1.8 (v/v/v), following the Bligh and Dyer [24] method.
The cholesterol analysis in meat was performed following the procedure described by Saldanha et al. [25]. Cholesterol determination utilized a high-performance liquid chromatography (HPLC) system (Shimadzu) equipped with a degasser (DGU-20 A5), and two pumps (LC-20 AT, with a UV detector). A C18 analytical column (250 mm × 4.6 mm × 3.5 μm) was used for the separation. Cholesterol identification was based on the comparison of retention times between the samples and the standard, while quantification relied on the corresponding peak areas. The chromatographic data were processed with LabSolutions® software 6.81 version (Shimadzu, Kyoto, Japan).
2.8. Fatty Acid Composition
The fatty acid composition analysis followed the methodology described by Bannon et al. [26]. Fatty acid methyl esters were analyzed using a Shimadzu GC-2010 Plus gas chromatography system (Shimadzu, Kyoto, Japan), equipped with a Flame Ionization Detector (FID) and an Rt-2560 fused silica capillary column (100 m, 0.25 mm i.d.). Gas flow rates (White Martins) were 40 mL/min for the carrier gas (H2), 30 mL/min for the auxiliary gas (N2), and 400 mL/min for the synthetic flame air. The sample split ratio was 90:10. The operating parameters were optimized to ensure the best resolution. The injector and detector temperatures were set at 225 °C and 260 °C, respectively. The column temperature program started at 140 °C for 5 min, followed by a ramp of 3 °C/min until 245 °C, where it was held for 20 min, resulting in a total analysis time of 60 min. Injections were performed in duplicate with a volume of 1.0 μL each. Peak areas of fatty acid methyl esters were determined using GCSolution® software 6.81 version.
Fatty acid methyl esters were identified by comparing the retention times of sample constituents with those of a mixture of fatty acid methyl ester standards (Mix C4-C24-18919-1 AMP, Supelco, MilliporeSigma, Burlington, MA, USA). Additionally, comparisons were made with standards containing the c9-t11 and t10-c12 geometric isomers of linoleic acid (O-5632 Sigma, MilliporeSigma, Burlington, MA, USA).
Fatty acids from fresh meat were quantified in g/100 g of total lipids using the internal standard methyl tricosanoate (23:0) (Sigma, USA). After weighing the lipids (~150 mg) for transesterification, 1000 μL of the internal standard solution with a known concentration (1.00 g/mL) was added to all samples. The concentration of fatty acids in the samples was calculated by normalization with internal standard.
2.9. Assessment of Nutritional Quality of Lipids in Fresh Meat
Desirable fatty acids were calculated by summing the content of the following acids: C18:0, monounsaturated, and polyunsaturated fatty acids. The nutritional quality of the lipid fraction of fresh meat was evaluated using the atherogenicity index (AI) and thrombogenicity index (TI), based on the fatty acids found in the samples. The calculations followed the method outlined by Ulbricht and Southgate [27]. After identifying the fatty acids, Δ-9 desaturase indices were determined based on equations from Malau-Aduli et al. [28].
2.10. Statistical Analysis
Data on intake, performance, digestibility, and feeding behavior were subjected to analysis of variance (ANOVA) and the F-test with a 5% significance level for type I errors. Variables with significant differences among groups were further analyzed using Tukey’s test with the same level of significance. The analyses were conducted using the PROC GLM procedure in SAS 9.1.3 [29].
3. Results
The dry matter allowance ranged from 9.50 to 17.35 kg/BW during the dry and rainy seasons, respectively. Despite this variation, the green leaf availability (kg DM/ha) was similar between the dry (1552 kg DM/ha) and rainy (1874 kg DM/ha) seasons (Table 4).
3.1. Intake and Apparent Digestibility
The different post-weaning supplementation strategies did not significantly influence (p > 0.05) the intakes of DM (total), forage DM, or organic matter (OM) by the steers. However, steers under the PS1/PS2 post-weaning strategy exhibited higher (p < 0.05) crude protein (CP) intakes compared to those under the MS/US and US/PS1 strategies (Table 5).
The supplementation strategies had no significant impact (p > 0.05) on the intakes of neutral detergent fiber (NDFap), non-fibrous carbohydrates (NFC), or total digestible nutrients (TDN) by the steers. Likewise, the apparent digestibility of DM, OM, NDF, and NFC did not differ (p > 0.05) in response to the supplementation strategies. However, the apparent digestibility of CP from the diet of steers supplemented with PS1/PS2 was higher (p < 0.05) compared to those of the other groups.
3.2. Feeding Behavior
The grazing time was similar (p > 0.05) for steers subjected to the MS/US and US/PS1 strategies but shorter (p < 0.05) for those supplemented with PS1/PS2. Steers under the US/PS1 post-weaning strategy spent more time (p < 0.05) ruminating and less time idle (Table 6).
Steers subjected to the PS1/PS2 post-weaning strategy spent more time (p < 0.05) at the trough and had higher (p < 0.05) biting rates compared to steers on US/PS1.
The animals subjected to the PS1/PS2 post-weaning strategy displayed greater feeding and rumination efficiencies (p < 0.05) compared with the US/PS1 group.
3.3. Performance and Carcass Traits
The supplementation strategies did not affect (p > 0.05) the body weight of steers at the end of the post-weaning phase. However, the average daily gain was higher for steers receiving the MS/US post-weaning strategy in comparison to the PS1/PS2 group (Table 7).
During the finishing period, the supplementation strategies had no significant effect (p > 0.05) on the slaughter weight. As observed in the post-weaning phase, the average daily gain during the finishing period was also similar between the MS/US and US/PS1 groups, but lower (p < 0.05) in those finished with the PS1/PS2 strategy. However, the hot carcass weight and backfat thickness were consistently higher (p < 0.05) for steers in the PS1/PS2 post-weaning and finishing strategy compared to the other groups.
3.4. Proximate and Fatty Acid Composition of Meat
The post-weaning and finishing strategies did not have a significant effect (p > 0.05) on the protein or cholesterol content of the meat from the steers. However, steers subjected to the PS1/PS2 strategy produced meat with a significantly higher (p < 0.05) total lipid content (Table 8).
In addition to the total lipid content, the supplementation strategies had a significant influence (p < 0.05) on the levels of various fatty acids, including C20:0, C24:0, C14:1, C15:1, C18:1n9t, C18:1n9c, C18:3n3, C18:2c9t11, C18:2t10c12, and C20:5n3, and on the total sum of polyunsaturated fatty acids (Table 9).
The content of desirable fatty acids, as well as the atherogenicity and thrombogenicity indices of the steers’ meat, was not influenced by the post-weaning and finishing supplementation strategies. Furthermore, there was a predominance of ω-6 fatty acids in the meat from steers that received the PS1/PS2 strategy and ω-3 fatty acids in those that received the MS/US strategy (Table 10).
4. Discussion
The DM and OM intakes by steers were not significantly influenced by the supplementation strategies. This outcome could be attributed to the consistent availability and quality of the pasture, including green dry matter, green leaves, and pasture protein content, during both the post-weaning and finishing stages [30]. The greater availability of dry matter enabled the steers to select portions of pasture with a higher nutritional value (green leaves), leading to similar forage intakes across the tested strategies [31]. Additionally, the relatively low levels (>1 g/kg BW) of supplementation used (1 and 2 g/kg BW) and the similar composition of the supplements meant that the supplementation had minimal substitutive or additive effects on intake [32]. In a related context, [33] found that, during the rainy season on tropical pasture, steers given either mineral salt with a urea or concentrate supplement at 1 or 2 g/kg BW showed no differences in DM intake, suggesting that forage availability during the rainy season can significantly impact the effects of supplementation in cattle.
Neutral detergent fiber is the major component of forage dry matter, and the intake of this fraction reflected the pattern observed for dietary DM [34]. However, the low levels of NFC in the supplements (SP1 and SP2) could explain why the supplementation strategies had no significant effect on NFC and TDN intakes [35]. In contrast, Rocha et al. [7] reported that using more intensive supplementation strategies increased NFC and TDN intakes among steers finished on tropical pasture throughout the year.
The elevated levels of CP in the supplements (SP1 and SP2), derived from both true protein and non-protein nitrogen (NPN), account for the approximately 100 g/day increase in CP intake among steers following the PS1/PS2 post-weaning and finishing strategy [36]. The CP content in the pasture during both the dry season (95.0 g/kg) and the rainy season (83.0 g/kg) was already sufficient to meet the requirements for adequate ruminal fermentation [37]. However, the provision of true protein (as opposed to solely NPN, available in the urea-based supplement [US]) throughout the dry and rainy seasons (the differential of the PS1/PS2 strategy) could have supported a greater population of bacteria involved in ruminal microbial protein synthesis [38], resulting in higher digestibility, a better amino acid profile, and the increased ruminal production of volatile fatty acids [39].
We anticipated that the US/PS1 and PS1/PS2 strategies would result in greater apparent digestibilities of OM and NDF in the diets. This expectation was based on the well-documented effect of synchrony in ruminal degradation rates between nitrogen sources and organic matter potentially fermentable in cattle rumen [5,40]. However, the high CP content in the pasture, coupled with the provision of forage portions with a superior nutritional value, may have resulted in the apparent digestibilities of OM and NDF in the MS/US strategy being on par with those observed in the US/PS1 and PS1/PS2 strategies, which had a higher CP supply, throughout the post-weaning period [41]. In this respect, the greater apparent digestibility of CP in the diet of steers receiving the PS1/PS2 strategy can be attributed to their higher CP intake and possibly greater synthesis of microbial protein, which has high intestinal digestibility in the rumen of animals under this strategy in the post-weaning phase [42]. Carvalho et al. [43] also reported an increase in CP digestibility when supplementation levels increased from 1 to 2 g/kg BW for calves on tropical pasture during the post-weaning period.
Steers that had protein supplements available throughout the year (PS1/PS2) spent less time grazing and ruminating, possibly because they spent more time at the trough or idle compared to those subjected to the MS/US and US/PS1 strategies [44]. This change in daily grazing patterns for steers in the PS1/PS2 strategy may be related to an increased time spent selecting pasture—an observation supported by their higher biting rate [45]. Furthermore, we propose that the increased consumption of supplement (as inferred from its year-round availability and the prolonged time at the trough), along with the higher level of pasture selection, may have resulted in rumen cuds with a higher ruminal DM content, leading to more chews per cud but lower levels of NDF, thereby reducing chewing time per cud [46]. Rocha et al. [47] also reported a longer chewing time per day and a shorter chewing time per ruminated cud for steers subjected to higher levels of dietary supplementation throughout the year.
Even though the body weight at the end of the post-weaning period and at slaughter was not affected by the supplementation strategies used, the average daily gain (ADG) was lower for steers that underwent post-weaning and finishing with the PS1/PS2 strategy compared to those subjected to MS/US and US/PS1 strategies. Sampaio et al. [9] also observed lower ADG in steers receiving protein–energy supplementation compared to those given only a mineral mixture. The reduced ADG in PS1/PS2 animals may be due to a lower gastrointestinal tract content weight. The ingestion of protein supplements in this strategy could accelerate the passage rate and lead to quicker gastrointestinal content disappearance, resulting in a lower body weight [48]. Moreover, the greater supplement intake throughout the year in the PS1/PS2 strategy might have altered body and gain composition in steers, leading to increased fat deposition in the carcass. This increased energy demand for maintenance and growth adversely affected feed efficiency [49].
On the other hand, the carcass weight and yield of steers finished with PS1/PS2 were consistently higher, likely due to the greater metabolizable protein and energy intake in the PS1/PS2 strategy compared to other strategies [50]. Canozzi et al. [51] also reported that carcass weight increased with higher supplementation levels during the finishing phase. The year-round supplementation in the PS1/PS2 strategy likely resulted in a larger rumen bacterial population, leading to increased microbial protein synthesis and volatile fatty acid production [52]. The latter is associated with lipogenesis processes in bovines, which may explain the higher carcass fatness (thicker subcutaneous fat layer) and greater intramuscular fat in the meat (i.e., more total meat fat) [53]. Additionally, various studies [54,55] indicate that increased concentrate supplementation at pasture finishing correlates with a rise in intramuscular fat in beef.
Steers finished with the MS/US strategy (lower intensification) produced meat with higher levels of C20:0, C24:0, C14:1, C18:1n9c, C18:2c9t11, C18:2t10c12, C18:3, and C20:5n3, and a higher sum of polyunsaturated fatty acids. This increase could be linked to the greater forage intake and absence of concentrate consumption in the MS/US strategy, resulting in a higher intake of C20:0, C24:0, and C18:3—fatty acids commonly found in tropical grasses [56,57]. Furthermore, the higher availability of C18:3 from forage in the rumen of MS/US steers leads to a larger amount of unsaturated fatty acids available for ruminal bacteria to biohydrogenate [58], explaining the elevated concentration of C18:1n9c, C18:2c9t11, and C18:2t10c12, which are conjugated linoleic acid (CLA) isomers [59].
The lower levels of triglycerides in the meat of MS/US steers (see meat fat) could account for the higher levels of C20:5n3, typically associated with phospholipids in myocyte membranes, leading to a relatively higher concentration of phospholipids in the meat of steers with a lower neutral lipid deposition [60]. The greater deposition of C18:3 and C20:5n3 fatty acids explains the higher sum of ω-3 fatty acids and the lower ω-6:ω-3 ratio observed in the meat from MS/US steers. Silva et al. [54] found that meat from steers supplemented only with mineral mixture contained more ω-3 fatty acids and a lower ω-6:ω-3 ratio compared to that of supplemented animals.
On the other hand, the greater ruminal bacterial activity in PS1/PS2 steers may explain the higher presence of odd-chain fatty acids (C15:1), derived from the membrane of the bacteria [61]. Additionally, the greater presence of C18:1n9t in the meat from the steers might be associated with the higher production of trans-11 isomer shifts in the rumen due to the increased starch presence provided by the supplement [62]. The PS1/PS2 strategy also produced meat with a higher ω-6 fatty acid content, likely due to the vegetable oil in the grain-based supplement [63]. Despite the higher ω-6:ω-3 ratio, the PS1/PS2 supplementation strategy produced similar meat in terms of fatty acid profile, atherogenicity, and thrombogenicity indices, demonstrating that increased concentrate supplementation (as used in this study) maintains a desirable fatty acid composition in meat [64].
5. Conclusions
Restricted concentrate supplementation (mineral salt and mineral salt with urea weight during the rainy and dry seasons, respectively) in the post-weaning and finishing phases of steers improved the average daily gain and content of polyunsaturated fatty acids and ω-3 fatty acids in the meat. Moderate concentrate supplementation (1 and 2 g/kg of body weight during the rainy and dry seasons, respectively) in the post-weaning and finishing phases of steers improved crude protein intake and digestibility, feeding and rumination efficiency, carcass weight and fatness, and intramuscular fat. However, this strategy reduced the total ω-3 fatty acids and conjugated linoleic acid isomers in the meat. Concentrate supplementation rates of 1 g/kg during the rainy season and 2 g/kg during the dry season are recommended for steers on tropical pasture during the post-weaning and finishing stages.
Author Contributions
Conceptualization, D.C.C.-D., L.H.S., F.F.d.S., L.V.S., A.P.G.d.S., M.d.C.S., W.Y.S.D., O.R.A.M., T.R.P., J.W.D.S., T.L.A.C.d.A., D.M.d.L.J. and R.R.S.; methodology, D.C.C.-D., L.H.S., F.F.d.S., L.V.S., A.P.G.d.S., M.d.C.S., W.Y.S.D., O.R.A.M., T.R.P., J.W.D.S., T.L.A.C.d.A., D.M.d.L.J. and R.R.S.; software, D.C.C.-D., L.H.S., F.F.d.S., L.V.S., A.P.G.d.S., M.d.C.S., W.Y.S.D., O.R.A.M., T.R.P., J.W.D.S., T.L.A.C.d.A., D.M.d.L.J. and R.R.S.; validation, D.C.C.-D., L.H.S., F.F.d.S., L.V.S., A.P.G.d.S., M.d.C.S., W.Y.S.D., O.R.A.M., T.R.P., J.W.D.S., T.L.A.C.d.A., D.M.d.L.J. and R.R.S.; formal analysis, D.C.C.-D., L.H.S., F.F.d.S., L.V.S., A.P.G.d.S., M.d.C.S., W.Y.S.D., O.R.A.M., T.R.P., J.W.D.S., T.L.A.C.d.A., D.M.d.L.J. and R.R.S.; investigation, D.C.C.-D., L.H.S., F.F.d.S., L.V.S., A.P.G.d.S., M.d.C.S., W.Y.S.D., O.R.A.M., T.R.P., J.W.D.S., T.L.A.C.d.A., D.M.d.L.J. and R.R.S.; resources, D.C.C.-D., L.H.S., F.F.d.S., L.V.S., A.P.G.d.S., M.d.C.S., W.Y.S.D., O.R.A.M., T.R.P., J.W.D.S., T.L.A.C.d.A., D.M.d.L.J. and R.R.S.; data curation, D.C.C.-D., L.H.S., F.F.d.S., T.L.A.C.d.A., D.M.d.L.J. and R.R.S.; writing—original draft preparation, D.C.C.-D., L.H.S., L.V.S., A.P.G.d.S., D.M.d.L.J. and R.R.S.; writing—review and editing, D.C.C.-D., L.H.S., D.M.d.L.J. and R.R.S.; visualization, D.C.C.-D., L.H.S., D.M.d.L.J. and R.R.S.; supervision, F.F.d.S., L.V.S., A.P.G.d.S. and R.R.S.; project administration, D.C.C.-D., L.H.S., F.F.d.S., L.V.S. and R.R.S.; funding acquisition, F.F.d.S. and R.R.S. All authors have read and agreed to the published version of the manuscript.
Funding
This research was funded by Coordination for the Improvement of Higher Education Personnel (CAPES); National Council for Scientific and Technological Development (CNPq) and the “Fundação de Amparo à Pesquisa do Estado da Bahia (FAPESB)”.
Institutional Review Board Statement
The animal study protocol was approved by the Ethics Committee) of Southwest Bahia State University (protocol code 100/2015).
Informed Consent Statement
Not applicable.
Data Availability Statement
None of the data were deposited in an official repository.
Acknowledgments
The authors would like to thank Aroldo Brandão de Oliveira.
Conflicts of Interest
The authors declare no conflicts of interest.
References
- Pent, G.J. Over-Yielding in Temperate Silvopastures: A Meta-Analysis. Agrofor. Syst. 2020, 94, 1741–1758. [Google Scholar] [CrossRef]
- Dubeux, J.C.B., Jr.; Sollenberger, L.E.; Muir, J.P.; Tedeschi, L.O.; Santos, M.V.F.; Cunha, M.V.; Mello, A.C.L.; DiLorenzo, N. Sustainable Intensification of Livestock Production on Pastures. Arch. Latinoam. Prod. Anim. 2017, 25, 97–111. [Google Scholar]
- Baggio, R.; Overbeck, G.E.; Durigan, G.; Pillar, V.D. To Graze or Not to Graze: A Core Question for Conservation and Sustainable Use of Grassy Ecosystems in Brazil. Perspect. Ecol. Conserv. 2021, 19, 256–266. [Google Scholar] [CrossRef]
- Ferreira, M.R.; da Silva Cardoso, A.; Andrade, M.E.B.; Brito, T.R.; Ruggieri, A.C. How Are Warm-Season Pastures’ Nutritive Value and Fermentation Characteristics Affected by Open Pasture, Silvopasture, and Sward Herbage Maturity? Agronomy 2023, 13, 1756. [Google Scholar] [CrossRef]
- Castro, M.M.D.; Cardoso, M.A.; Detmann, E.; Fonseca, M.A.; Sampaio, C.B.; Marcondes, M.I. In Vitro Ruminal Fermentation and Enteric Methane Production of Tropical Forage Added Nitrogen or Nitrogen plus Starch. Anim. Feed. Sci. Technol. 2021, 275, 114878. [Google Scholar] [CrossRef]
- Cazzuli, F.; Sánchez, J.; Hirigoyen, A.; Rovira, P.; Beretta, V.; Simeone, A.; Jaurena, M.; Durante, M.; Savian, J.V.; Poppi, D.; et al. Supplement Feed Efficiency of Growing Beef Cattle Grazing Native Campos Grasslands during Winter: A Collated Analysis. Transl. Anim. Sci. 2023, 7, txad028. [Google Scholar] [CrossRef] [PubMed]
- Rocha, W.J.B.; Silva, R.R.; da Silva, F.F.; de Carvalho, G.G.P.; da Silva, A.P.G.; Silva, J.W.D.; Paixão, T.R.; Freitas, T.B.; Mendes, F.B.L.; Barroso, D.S.; et al. Intake, Digestibility, and Growth Performance of Girolando Bulls Supplemented on Pasture in Bahia, Brazil. Trop. Anim. Health Prod. 2019, 51, 1413–1420. [Google Scholar] [CrossRef]
- Ramos, J.M.L.; Vargas, J.A.C.; Diniz, E.A.L.; Lacerda, N.G.; Mezzomo, R.; Alves, K.S.; Oliveira, L.R.S.; de Loureiro, J.P.B.; da Silva, P.R.; Gomes, D.I. Carcass Traits and Meat Characteristics of Grazing Nellore Cattle Submitted to Different Supplementation Strategies in the Tropics. Trop. Anim. Health Prod. 2022, 54, 362. [Google Scholar] [CrossRef] [PubMed]
- Sampaio, R.L.; de Resende, F.D.; Reis, R.A.; de Oliveira, I.M.; Custódio, L.; Fernandes, R.M.; Pazdiora, R.D.; Siqueira, G.R. The Nutritional Interrelationship between the Growing and Finishing Phases in Crossbred Cattle Raised in a Tropical System. Trop. Anim. Health Prod. 2017, 49, 1015–1024. [Google Scholar] [CrossRef]
- da Cunha Peixoto Vitor, A.; dos Santos Pedreira, M.; Silva, A.S.; Pezenti, E.; da Silva, L.C.; da Silva, H.A.; Diavão, J.; Morenz, M.J.F. Feeding Strategy during Growing Phase on the Performance and Carcass Traits in Beef Bulls Finished on the Pasture. Trop. Anim. Health Prod. 2022, 54, 302. [Google Scholar] [CrossRef]
- da Costa Gomes, R.; de Oliveira Menezes, G.R.; Favero, R.; Kazama, R.; Altrak, G.; Mizubuti, I.Y.; de Nadai Bonin Gomes, M.N.B.; Feijó, G.L.D.; Montagner, D.B.; de Araújo, T.L.A.C.; et al. Strategies of Virginiamycin Supplementation in the Postweaning Phase on Growth Performance and Carcass Quality of Beef Cattle. Trop. Anim. Health Prod. 2024, 56, 12. [Google Scholar] [CrossRef] [PubMed]
- Torrecilhas, J.A.; Vito, E.S.; Fiorentini, G.; de Souza Castagnino, P.; Simioni, T.A.; Lage, J.F.; Baldi, F.; Duarte, J.M.; da Silva, L.G.; Reis, R.A.; et al. Effects of Supplementation Strategies during the Growing Phase on Meat Quality of Beef Cattle Finished in Different Systems. Livest. Sci. 2021, 247, 104465. [Google Scholar] [CrossRef]
- NRC. Nutrient Requirements of Beef Cattle, 8th ed.; National Academies Press: Washington, DC, USA, 2016; ISBN 978-0-309-31702-3. [Google Scholar]
- Haydock, K.P.; Shaw, N.H. The Comparative Yield Method for Estimating Dry Matter Yield of Pasture. Aust. J. Exp. Agric. Anim. Husb. 1975, 15, 663–670. [Google Scholar] [CrossRef]
- Johnson, A.D. Sample Preparation and Chemical Analysis of Vrgrtation. In Measurement of Grassland Vegetation and Animal Production; t’Manetje, L., Ed.; Commonwealth Agricultural Bureaux: Farnham Royal, UK, 1978; Volume 1, pp. 96–102. [Google Scholar]
- Detmann, E.; Silva, T.E.; Valadares Filho, S.D.C.; Sampaio, C.B.; Palma, M.N.N. Prediction of the Energy Value of Cattle Diets Based on the Chemical Composition of Feeds. In Nutrient Requirements of Zebu and Crossbred Cattle; Valadares Filho, S.D.C., Costa e Silva, L.F., Gionbelli, M.P., Rotta, P.P., Marcondes, M.I., Chizzotti, M.L., Prados, L.F., Eds.; UFV: Vicosa, Brazil, 2016; pp. 89–126. [Google Scholar]
- Detmann, E.; de Souza, M.A.; Valadares Filho, S.D.C.; de Queiroz, A.C.; Berchielli, T.T.; Saliba, E.D.O.; Cabral, L.d.S.; Pina, D.d.S.; Ladeira, M.M.; Azevedo, J.A.G. Métodos Para Análise de Alimentos. In Visconde Branco Suprema; 2012; p. 214. [Google Scholar]
- Titgemeyer, E.C.; Armendariz, C.K.; Bindel, D.J.; Greenwood, R.H.; Löest, C.A. Evaluation of Titanium Dioxide as a Digestibility Marker for Cattle. J. Anim. Sci. 2001, 79, 1059. [Google Scholar] [CrossRef] [PubMed]
- Weiss, W.P. Energy Prediction Equations for Ruminant Feeds. In Proceedings of the 61th Cornell Nutrition Conference Feed Manufactures: October 19-21, 1999 Rochester Marriott Thruway Hotel, Rochester, NY, USA; Cornell University: Ithaca, NY, USA, 1999; pp. 176–185. [Google Scholar]
- Silva, R.R.; do Prado, I.N.; de Carvalho, G.G.P.; de Santana Junior, H.A.; da Silva, F.F.; Dias, D.L.S. Efeito Da Utilização de Três Intervalos de Observações Sobre a Precisão Dos Resultados Obtidos No Estudo Do Comportamento Ingestivo de Vacas Leiteiras Em Pastejo. Ciência Anim. Bras./Braz. Anim. Sci. 2008, 9, 319–326. [Google Scholar] [CrossRef]
- Bürger, P.J.; Pereira, J.C.; de Queiroz, A.C.; Coelho da Silva, J.F.; Valadares Filho, S.D.C.; Cecon, P.R.; Casali, A.D.P. Comportamento Ingestivo Em Bezerros Holandeses Alimentados Com Dietas Contendo Diferentes Níveis de Concentrado. Rev. Bras. Zootec. 2000, 29, 236–242. [Google Scholar] [CrossRef]
- Baggio, C.; de Faccio Carvalho, P.C.; da Silva, J.L.S.; Anghinoni, I.; Lopes, M.L.T.; Thurow, J.M. Padrões de Deslocamento e Captura de Forragem Por Novilhos Em Pastagem de Azevém-Anual e Aveia-Preta Manejada Sob Diferentes Alturas Em Sistema de Integração Lavoura-Pecuária. Rev. Bras. Zootec. 2009, 38, 215–222. [Google Scholar] [CrossRef]
- AOAC. Official Methods of Analysis, 20th ed.; Association of Official Agricultural Chemists: Washington, DC, USA, 2016. [Google Scholar]
- Bligh, E.G.; Dyer, W.J. A Rapid Method of Total Lipid Extraction and Purification. Can. J. Biochem. Physiol. 1959, 37, 911–917. [Google Scholar] [CrossRef] [PubMed]
- Saldanha, T.; Mazalli, M.R.; Bragagnolo, N. Avaliação Comparativa Entre Dois Métodos Para Determinação Do Colesterol Em Carnes e Leite. Ciência Tecnol. Aliment. 2004, 24, 109–113. [Google Scholar] [CrossRef]
- Bannon, C.D.; Craske, J.D.; Felder, D.L.; Garland, I.J.; Norman, L.M. Analysis of Fatty Acid Methyl Esters with High Accuracy and Reliability. J. Chromatogr. A 1987, 407, 231–241. [Google Scholar] [CrossRef]
- Ulbricht, T.L.V.; Southgate, D.a.T. Coronary Heart Disease: Seven Dietary Factors. Lancet 1991, 338, 985–992. [Google Scholar] [CrossRef] [PubMed]
- Malau-Aduli, A.E.O.; Siebert, B.D.; Bottema, C.D.K.; Pitchford, W.S. A Comparison of the Fatty Acid Composition of Triacylglycerols in Adipose Tissue from Limousin and Jersey Cattle. Aust. J. Agric. Res. 1997, 48, 715. [Google Scholar] [CrossRef]
- SAS, I. SAS User’s Guide: Basics 2008; SAS Institute: Tokyo, Japan, 2008.
- Bones, E.R.; Paris, W.; Costa, O.A.D.; de Paula, A.L.; Belli, V.P.; da Silva Neves, A.C.; de Menezes, L.F.G. Influence of Irrigation and Supplementation on Performance and Ingestive Behavior of Beef Cattle on Mixed Grass Pastures. Rev. Bras. Zootec. 2023, 52, e20220055. [Google Scholar] [CrossRef]
- de Moura Zanine, A.; Rebuffo, G.P.M.; de Jesus Ferreira, D.; de Souza, A.L.; Ribeiro, M.D.; Pinho, R.M.A.; Fajardo, M.; Sprunk, M. The Effects of Herbage Allowance on Pasture Characteristics and Milk Production of Dairy Cows. New Zealand J. Agric. Res. 2019, 62, 200–209. [Google Scholar] [CrossRef]
- Lins, T.O.J.D.’A.; Silva, R.R.; Mendes, F.B.L.; da Silva, F.F.; Bastos, E.S.; Paixão, T.R.; Silva, J.W.D.; da Conceição Santos, M.; Figueiredo, G.C.; Alba, H.D.R.; et al. Feeding Behavior of Post-Weaned Crossbred Steers Supplemented in the Dry Season of the Year. Trop. Anim. Health Prod. 2022, 54, 203. [Google Scholar] [CrossRef] [PubMed]
- de Souza, S.O.; Silva, R.R.; da Silva, F.F.; Gomes da Silva, A.P.; Santos, M.D.C.; Paiva Barbosa, R.; Lima Xavier, R.; Ribeiro Paixão, T.; Dallapicola da Costa, G.; Batista Peruna, A.; et al. Manejo Nutricional de Novillos Criados En Pastoreo y En Corral: Efectos En El Consumo, Digestibilidad, Rendimiento y Viabilidad Económica. Rev. Mex. Cienc. Pecu. 2021, 12, 105–119. [Google Scholar] [CrossRef]
- Riaz, M.Q.; Südekum, K.-H.; Clauss, M.; Jayanegara, A. Voluntary Feed Intake and Digestibility of Four Domestic Ruminant Species as Influenced by Dietary Constituents: A Meta-Analysis. Livest. Sci. 2014, 162, 76–85. [Google Scholar] [CrossRef]
- Brandão, R.K.C.; de Carvalho, G.G.P.; Silva, R.R.; Dias, D.L.S.; Mendes, F.B.L.; Lins, T.O.J.D.A.; Pereira, M.M.S.; Guimarães, J.O.; Tosto, M.S.L.; de A Rufino, L.M.; et al. Correlation between Production Performance and Feeding Behavior of Steers on Pasture during the Rainy-Dry Transition Period. Trop. Anim. Health Prod. 2018, 50, 105–111. [Google Scholar] [CrossRef]
- Ítavo, L.C.V.; Dias, A.M.; Ítavo, C.C.B.F.; Franco, G.L.; da Graça Morais, M.; Souza, A.R.D.L.; Nogueira, É.; Mateus, R.G.; Araujo, H.S.; de Moraes, G.J.; et al. Mineral-Nitrogen Supplementation to Finishing Nellore Steers in Deferred Pasture. Rev. Bras. Saúde Produção Anim. 2017, 18, 576–586. [Google Scholar] [CrossRef]
- Batista, E.D.; Detmann, E.; Valadares Filho, S.C.; Titgemeyer, E.C.; Valadares, R.F.D. The Effect of CP Concentration in the Diet on Urea Kinetics and Microbial Usage of Recycled Urea in Cattle: A Meta-Analysis. Animal 2017, 11, 1303–1311. [Google Scholar] [CrossRef]
- da Silva-Marques, R.P.; Zervoudakis, J.T.; Nakazato, L.; da Silva Cabral, L.; Hatamoto-Zervoudakis, L.K.; da Silva, M.I.L.; do Nascimento Matos, N.B.; Pitchenin, L.C. Quantitative QPCR Analysis of Ruminal Microorganisms in Beef Cattle Grazing in Pastures in the Rainy Season and Supplemented with Different Protein Levels. Curr. Microbiol. 2018, 75, 1025–1032. [Google Scholar] [CrossRef]
- Teobaldo, R.W.; Granja-Salcedo, Y.T.; da Silva Cardoso, A.; Constancio, M.T.L.; Brito, T.R.; Romanzini, E.P.; Reis, R.A. The Impact of Mineral and Energy Supplementation and Phytogenic Compounds on Rumen Microbial Diversity and Nitrogen Utilization in Grazing Beef Cattle. Microorganisms 2023, 11, 810. [Google Scholar] [CrossRef] [PubMed]
- Calsamiglia, S.; Ferret, A.; Reynolds, C.K.; Kristensen, N.B.; van Vuuren, A.M. Strategies for Optimizing Nitrogen Use by Ruminants. Animal 2010, 4, 1184–1196. [Google Scholar] [CrossRef] [PubMed]
- Franco, M.O.; Detmann, E.; Batista, E.D.; Rufino, L.M.A.; Paulino, M.F.; Valadares Filho, S.C. Nutritional Performance and Metabolic Characteristics of Cattle Fed Tropical Forages with Protein and Starch Supplementation. An. Acad. Bras. Cienc. 2021, 93, e20190487. [Google Scholar] [CrossRef] [PubMed]
- Rufino, L.M.A.; Batista, E.D.; Rodrigues, J.P.P.; Valadares Filho, S.C.; Paulino, M.F.; Costa e Silva, L.F.; Detmann, E. Effects of the Amount and Frequency of Nitrogen Supplementation on Intake, Digestion, and Metabolism in Cattle Fed Low-Quality Tropical Grass. Anim. Feed. Sci. Technol. 2020, 260, 114367. [Google Scholar] [CrossRef]
- Carvalho, V.M.; Silva, R.R.; Lins, T.O.J.D.; Barroso, D.S.; Rocha, T.R.; Silva, J.W.D.; Santos, M.C.; de Almeida, K.V.; Prado, I.N. Supplementation Strategies for Crossbred Steers on Brachiaria Brizantha Pasture during the Dry Season: Effects on Performance, Intake, Digestibility and Ingestive Behavior. Acta Sci. 2024, 46, e69224. [Google Scholar]
- Brandão, R.K.C.; de Carvalho, G.G.P.; Silva, R.R.; Dias, D.L.S.; Mendes, F.B.L.; Lins, T.O.J.D.; Filho, G.A.; de Souza, S.O.; Barroso, D.S.; de Almeida Rufino, L.M.; et al. Comparison of Protein and Energy Supplementation to Mineral Supplementation on Feeding Behavior of Grazing Cattle during the Rainy to the Dry Season Transition. Springerplus 2016, 5, 933. [Google Scholar] [CrossRef] [PubMed]
- Da Trindade, J.K.; Pinto, C.E.; Neves, F.P.; Mezzalira, J.C.; Bremm, C.; Genro, T.C.M.; Tischler, M.R.; Nabinger, C.; Gonda, H.L.; Carvalho, P.C.F. Forage Allowance as a Target of Grazing Management: Implications on Grazing Time and Forage Searching. Rangel. Ecol. Manag. 2012, 65, 382–393. [Google Scholar] [CrossRef]
- Rosales, J.D.J.; Massiotti, R.D.A. Comportamiento de Ingestión y Consumo de Forraje Por Vacas En Pastoreo En Clima Templado. Revisión. Rev. Mex. Cienc. Pecu. 2022, 13, 743–762. [Google Scholar] [CrossRef]
- Rocha, W.J.B.; Silva, R.R.; da Silva, F.F.; de Carvalho, G.G.P.; da Silva, A.P.G.; Silva, J.W.D.; Santos, L.V.; Filho, G.A.; Bastos, E.S.; Carvalho, V.M.; et al. Ingestive Behavior of Girolando Steers Supplemented on Tropical Pastures. Trop. Anim. Health Prod. 2022, 54, 205. [Google Scholar] [CrossRef]
- Vieira, B.R.; Azenha, M.V.; Casagrande, D.R.; Costa, D.F.A.; Ruggieri, A.C.; Berchielli, T.T.; Reis, R.A. Ingestive Behavior of Supplemented Nellore Heifers Grazing Palisadegrass Pastures Managed with Different Sward Heights. Anim. Sci. J. 2017, 88, 696–704. [Google Scholar] [CrossRef] [PubMed]
- Koscheck, J.F.W.; Romanzini, E.P.; Barbero, R.P.; Delevatti, L.M.; Ferrari, A.C.; Mulliniks, J.T.; Mousquer, C.J.; Berchielli, T.T.; Reis, R.A. How Do Animal Performance and Methane Emissions Vary with Forage Management Intensification and Supplementation? Anim. Prod. Sci. 2020, 60, 1201. [Google Scholar] [CrossRef]
- Missio, R.L.; de Souza e Souza, S.; Paris, W.; Cavazzana, J.F.; Severo, M.M.; Severo, I.K.; Poggere, J.M.; Costa, O.A.D.; Borquis, R.R.A.; de Menezes, L.F.G. Influence of Low and Medium Intake Supplements in the Growing Phase of Steers Grazing in the Tropical Pasture and Finished in Feedlot. Ciência Rural. 2024, 54, e20220661. [Google Scholar] [CrossRef]
- Canozzi, M.E.A.; Banchero, G.; Fernández, E.; La Manna, A.; Clariget, J.M. Individual Feed Intake and Performance of Finishing Steers on Ryegrass Pasture Supplemented with Increasing Amounts of Corn Using an Automated Feeding System. Livest. Sci. 2023, 269, 105169. [Google Scholar] [CrossRef]
- Martinez-Fernandez, G.; Jiao, J.; Padmanabha, J.; Denman, S.E.; McSweeney, C.S. Correction: Martinez-Fernandez et al. Seasonal and Nutrient Supplement Responses in Rumen Microbiota Structure and Metabolites of Tropical Rangeland Cattle. Microorganisms 2020, 8, 1550. Microorganisms 2021, 9, 1053. [Google Scholar] [CrossRef] [PubMed]
- Ladeira, M.M.; Schoonmaker, J.P.; Gionbelli, M.P.; Dias, J.C.O.; Gionbelli, T.R.S.; Carvalho, R.R.; Teixeira, P.D. Nutrigenomics and Beef Quality: A Review about Lipogenesis. Int. J. Mol. Sci. 2016, 17, 918. [Google Scholar] [CrossRef]
- Silva, R.R.; do Prado, I.N.; da Silva, F.F.; Rotta, P.P.; Rodrigues, L.B.O.; do Prado, R.M.; de Carvalho Mesquita, B.M.A.; Alba, H.D.R.; de Carvalho, G.G.P. Fatty Acid Profile and Chemical Composition of Meat from Nellore Steers Finished on Pasture with Different Amounts of Supplementation. Can. J. Anim. Sci. 2021, 101, 558–566. [Google Scholar] [CrossRef]
- Park, S.J.; Beak, S.; Jung, D.J.S.; Kim, S.Y.; Jeong, I.H.; Piao, M.Y.; Kang, H.J.; Fassah, D.M.; Na, S.W.; Yoo, S.P.; et al. Genetic, Management, and Nutritional Factors Affecting Intramuscular Fat Deposition in Beef Cattle—A Review. Asian-Australas. J. Anim. Sci. 2018, 31, 1043–1061. [Google Scholar] [CrossRef]
- Dias, K.M.; Schmitt, D.; Rodolfo, G.R.; Deschamps, F.C.; Camargo, G.N.; Pereira, R.S.; Sbrissia, A.F. Fatty Acid Profile in Vertical Strata of Elephant Grass Subjected to Intermittent Stocking. An. Acad. Bras. Cienc. 2017, 89, 1707–1718. [Google Scholar] [CrossRef]
- Whetsell, M.; Rayburn, E. Variation in Fatty Acids Concentration in Grasses, Legumes, and Forbs in the Allegheny Plateau. Agronomy 2022, 12, 1693. [Google Scholar] [CrossRef]
- Glasser, F.; Doreau, M.; Maxin, G.; Baumont, R. Fat and Fatty Acid Content and Composition of Forages: A Meta-Analysis. Anim. Feed. Sci. Technol. 2013, 185, 19–34. [Google Scholar] [CrossRef]
- Balcazar, I.C.A.; Rivera, L.D.G.; Chavira, J.S.; Drouaillet, B.E.; Albarrán, M.R.; Martínez, Y.B. Relationship between the Composition of Lipids in Forages and the Concentration of Conjugated Linoleic Acid in Cow’s Milk: A Review. Animals 2022, 12, 1621. [Google Scholar] [CrossRef] [PubMed]
- Urrutia, O.; Mendizabal, J.A.; Alfonso, L.; Soret, B.; Insausti, K.; Arana, A. Adipose Tissue Modification through Feeding Strategies and Their Implication on Adipogenesis and Adipose Tissue Metabolism in Ruminants. Int. J. Mol. Sci. 2020, 21, 3183. [Google Scholar] [CrossRef] [PubMed]
- Lourenço, M.; Ramos-Morales, E.; Wallace, R.J. The Role of Microbes in Rumen Lipolysis and Biohydrogenation and Their Manipulation. Animal 2010, 4, 1008–1023. [Google Scholar] [CrossRef] [PubMed]
- Alves, S.P.; Bessa, R.J.B. The Trans-10, Cis-15 18:2: A Missing Intermediate of Trans-10 Shifted Rumen Biohydrogenation Pathway? Lipids 2014, 49, 527–541. [Google Scholar] [CrossRef] [PubMed]
- Cappellozza, B.I.; Cooke, R.F.; Harvey, K.M. Omega-6 Fatty Acids: A Sustainable Alternative to Improve Beef Production Efficiency. Animals 2021, 11, 1764. [Google Scholar] [CrossRef]
- Chen, J.; Liu, H. Nutritional Indices for Assessing Fatty Acids: A Mini-Review. Int. J. Mol. Sci. 2020, 21, 5695. [Google Scholar] [CrossRef]
Table 1.
Supplementation strategies.
| Restricted (MS/US) | Low (US/PS1) | Moderate (PS1/PS2) | |
|---|---|---|---|
| Rainy 1 | Mineral salt ad libitum | Mineral salt with urea ad libitum | Protein supplement (1 g/kg of BW 3) |
| Dry 2 | Mineral salt with urea ad libitum | Protein supplement (1 g/kg of BW 3) | Protein supplement (2 g/kg of BW 3) |
1 Rainy season, between the months of January and July; 2 Dry season, between the months of August and December; 3 Body weight.
Table 2.
Proportion of ingredients in the concentrates (%, dry-matter basis).
| Rainy Season | Dry Season | |||||
|---|---|---|---|---|---|---|
| MS 1 | US 2 | PS1 3 | US | PS1 | PS2 4 | |
| Grain sorghum | - | - | 56.55 | - | 56.55 | 49.20 |
| Soybean meal | - | - | 19.38 | - | 19.38 | 31.34 |
| Urea | - | 25 | 14.93 | 25 | 14.93 | 13.94 |
| Mineral salt 5 | 100 | 75 | 9.14 | 75 | 9.14 | 5.54 |
1 Mineral salt ad libitum; 2 Mineral salt with urea ad libitum; 3 Protein supplement (1 g/kg of body weight); 4 Protein supplement (2 g/kg of body weight). 5 Composition: calcium 235 g; phosphorus 60 g; magnesium 16 g; sulfur 12 g; cobalt 150 mg; copper 1600 mg; iodine 190 mg; manganese 1400 mg; iron 1000 mg; selenium 32 mg; zinc 6000 mg; 1120 mg; fluoride (maximum) 1600 mg.
Table 3.
Chemical composition (g/kg) of forage (Urochloa brizantha cv. Marandu) and concentrate supplements used in the experiment.
Table 3.
Chemical composition (g/kg) of forage (Urochloa brizantha cv. Marandu) and concentrate supplements used in the experiment.
| Forage (Simulated Grazing) | Protein Supplement Level | |||
|---|---|---|---|---|
| Rainy | Dry | 1 g/kg | 2 g/kg | |
| Dry matter | 263.2 | 400.0 | 895.9 | 897.7 |
| Organic matter | 912.9 | 889.0 | 894.4 | 886.6 |
| Ash | 87.2 | 110.0 | 105.5 | 113.4 |
| Crude protein | 95.0 | 83.0 | 465.8 | 397.6 |
| Ether extract | 16.6 | 22.6 | 32.9 | 30.9 |
| Total carbohydrates | 805.9 | 778.0 | 397.9 | 458.1 |
| NDFap | 696.0 | 653.5 | 254.6 | 336.6 |
| NFC | 156.9 | 129.5 | 160.7 | 121.5 |
| iNDF | 185.0 | 250.0 | 12.2 | 13.8 |
| TDN | 509.6 | 489.8 | 613.8 | 653.1 |
NFC: non-fibrous carbohydrates; NDFap: neutral detergent fiber corrected for ash and protein; iNDF: indigestible neutral detergent fiber; TDN: total digestible nutrients.
Table 4.
Canopy characteristics of Urochloa brizantha cv. Marandu pasture.
| Characteristics of the Forage Canopy | Season | |
|---|---|---|
| Dry | Rainy | |
| Total dry matter (kg/ha) | 4236 | 6319 |
| Potentially digestible dry matter (kg DM 1/ha) | 3446 | 5205 |
| Green dry matter (kg/ha) | 3098 | 3973 |
| Stem + sheath (kg DM/ha) | 1538 | 2099 |
| Green leaf (kg DM/ha) | 1552 | 1874 |
| Senescent material (kg DM/ha) | 1147 | 1296 |
| Dry matter allowance (kg/BW 2) | 9.50 | 17.35 |
1 Dry matter; 2 Body weight.
Table 5.
Intake and apparent digestibility of nutrients from the diet of steers * receiving supplement-reduction strategies on tropical pasture during the post-weaning period.
Table 5.
Intake and apparent digestibility of nutrients from the diet of steers * receiving supplement-reduction strategies on tropical pasture during the post-weaning period.
| Supplementation Strategy | SEM 4 | p-Value 5 | |||
|---|---|---|---|---|---|
| MS/US 1 | US/PS1 2 | PS1/PS2 3 | |||
| Intake (kg/day) | |||||
| Total dry matter | 7.41 | 7.42 | 7.79 | 1.016 | 0.613 |
| Forage dry matter | 7.41 | 7.42 | 7.42 | 0.991 | 0.999 |
| Organic matter | 6.83 | 6.83 | 7.16 | 0.935 | 0.631 |
| Crude protein | 0.74 b | 0.77 b | 0.91 a | 0.122 | 0.002 |
| Ether extract | 0.13 | 0.13 | 0.14 | 0.018 | 0.205 |
| NDFap 6 | 5.01 | 5.01 | 5.12 | 0.676 | 0.911 |
| NFC 7 | 1.15 | 1.15 | 1.21 | 0.157 | 0.615 |
| TDN 8 | 3.87 | 3.95 | 4.23 | 0.667 | 0.435 |
| Digestibility (%) | |||||
| Dry matter | 48.71 | 49.72 | 51.20 | 3.357 | 0.230 |
| Organic matter | 51.50 | 52.84 | 54.11 | 3.248 | 0.185 |
| Crude protein | 41.03 b | 41.60 b | 48.77 a | 3.806 | 0.000 |
| Ether extract | 67.03 | 69.85 | 72.88 | 5.671 | 0.069 |
| NDFap 6 | 54.02 | 55.51 | 55.61 | 3.424 | 0.482 |
| NFC 7 | 57.14 | 56.10 | 56.52 | 4.227 | 0.846 |
| TDN 8 | 52.22 | 53.23 | 54.30 | 3.177 | 0.275 |
* The animals weighed on average, 378.3 kg at the time of intake. 1 Mineral salt ad libitum in the rainy season/Mineral salt with urea in the dry season; 2 Mineral salt with urea in the rainy season/Protein supplement (1 g/kg of body weight) in the dry season; 3 Protein supplement (1 g/kg body weight) in the rainy season/Protein supplement (2 g/kg body weight) in the dry season. 4 Standard deviation of the mean; 5 Means followed by letters differ statistically at a 5% probability level using Tukey’s test; 6 Neutral detergent fiber corrected for ash and protein; 7 Non-fiber carbohydrates; 8 Total digestible nutrients.
Table 6.
Feeding behavior of steers * receiving supplement-reduction strategies on tropical pasture during the post-weaning period.
Table 6.
Feeding behavior of steers * receiving supplement-reduction strategies on tropical pasture during the post-weaning period.
| Supplementation Strategy | SEM 4 | p-Value 5 | |||
|---|---|---|---|---|---|
| MS/US 1 | US/PS1 2 | PS1/PS2 3 | |||
| Grazing time (min) | 497.00 a | 534.00 a | 437.00 b | 76.923 | <0.0001 |
| Rumination time (min) | 365.00 b | 410.00 a | 352.00 b | 65.366 | 0.0013 |
| Idle time (min) | 572.00 b | 488.00 c | 640.00 a | 94.350 | <0.0001 |
| Time at trough (min) | 4.50 b | 7.10 b | 10.60 a | 5.671 | <0.0002 |
| Biting time (s) | 22.00 | 23.00 | 22.00 | 2.667 | 0.4701 |
| Biting rate (n/min) | 49.00 ab | 470.00 b | 52.00 a | 8.337 | 0.0311 |
| Ruminated cuds (n/day) | 395.00 b | 463.00 a | 424.00 ab | 105.85 | 0.0378 |
| Chewing (n/cud) | 50.00 b | 53.00 ab | 58.00 a | 10.953 | 0.0262 |
| Chewing (s/cud) | 57.00 a | 55.00 ab | 51.00 b | 8.552 | 0.0147 |
| Feeding efficiency (kg DM 6/h) | 0.92 ab | 0.84 b | 1.07 a | 0.245 | 0.0009 |
| Feeding efficiency (kg NDFap 7/h) | 0.62 ab | 0.57 b | 0.70 a | 0.163 | 0.0046 |
| Rumination efficiency (kg DM/h) | 1.23 ab | 1.12 b | 1.37 a | 0.260 | 0.0010 |
| Rumination efficiency (kg NDFap/h) | 0.83 ab | 0.76 b | 0.90 a | 0.172 | 0.0057 |
* The animals weighed on average, 378.3 kg at the time of intake. 1 Mineral salt ad libitum in the rainy season/Mineral salt with urea in the dry season; 2 Mineral salt with urea in the rainy season/Protein supplement (1 g/kg of body weight) in the dry season; 3 Protein supplement (1 g/kg body weight) in the rainy season/Protein supplement (2 g/kg body weight) in the dry season. 4 Standard deviation of the mean; 5 Means followed by letters differ statistically at a 5% probability level using Tukey’s test; 6 Dry matter; 7 Neutral detergent fiber corrected for ash and protein.
Table 7.
Performance and carcass traits of steers receiving supplement-reduction strategies on tropical pasture during the post-weaning and finishing periods.
Table 7.
Performance and carcass traits of steers receiving supplement-reduction strategies on tropical pasture during the post-weaning and finishing periods.
| Supplementation Strategy | SEM 4 | p-Value 5 | |||
|---|---|---|---|---|---|
| MS/US 1 | US/PS1 2 | PS1/PS2 3 | |||
| Post-weaning (240 days) | |||||
| Initial body weight (kg) | 332.41 | 331.91 | 340.82 | 44.762 | 0.8770 |
| Final body weight (kg) | 424.86 | 412.68 | 415.45 | 50.788 | 0.8410 |
| Average daily gain (kg/day) | 0.880 a | 0.769 ab | 0.710 b | 0.148 | 0.0350 |
| Feed efficiency | 0.120 a | 0.100 ab | 0.090 b | 0.019 | 0.0060 |
| Finishing (70 days) | |||||
| Initial body weight (kg) | 430.64 | 426.45 | 455.27 | 52.057 | 0.3857 |
| Final body weight (kg) | 477.30 | 491.20 | 502.70 | 50.805 | 0.5506 |
| Average daily gain (kg/day) | 0.61 a | 0.69 a | 0.45 b | 0.181 | 0.0043 |
| Hot carcass weight (kg) | 232.83 c | 253.27 b | 267.44 a | 12.082 | <0.0001 |
| Hot carcass yield (%) | 50.23 b | 50.65 b | 52.48 a | 2.014 | <0.0001 |
| Ribeye area (cm2) | 65.64 b | 73.25 a | 74.37 a | 3.689 | <0.0001 |
| Backfat thickness (mm) | 3.32 c | 3.78 b | 4.06 a | 0.224 | <0.0001 |
1 Mineral salt ad libitum in the rainy season/Mineral salt with urea in the dry season; 2 Mineral salt with urea in the rainy season/Protein supplement (1 g/kg of body weight) in the dry season; 3 Protein supplement (1 g/kg body weight) in the rainy season/Protein supplement (2 g/kg body weight) in the dry season. 4 Standard deviation of the mean; 5 Means followed by letters differ statistically at a 5% probability level using Tukey’s test.
Table 8.
Proximate composition and cholesterol content of meat (Longissimus dorsi) from steers finished with supplement-reduction strategies on tropical pasture.
Table 8.
Proximate composition and cholesterol content of meat (Longissimus dorsi) from steers finished with supplement-reduction strategies on tropical pasture.
| Supplementation Strategy | SEM 4 | p-Value 5 | |||
|---|---|---|---|---|---|
| MS/US 1 | US/PS1 2 | PS1/PS2 3 | |||
| Moisture (%) | 71.03 | 70.57 | 70.50 | 1.878 | 0.3507 |
| Ash (%) | 3.12 | 3.48 | 3.56 | 0.182 | 0.1108 |
| Protein (%) | 23.55 | 22.99 | 22.03 | 2.057 | 0.0683 |
| Total lipids (%) | 2.25 b | 3.00 b | 3.93 a | 0.607 | 0.0001 |
| Cholesterol (mg/100 g) | 43.48 | 43.03 | 44.08 | 3.561 | 0.1453 |
1 Mineral salt ad libitum in the rainy season/Mineral salt with urea in the dry season; 2 Mineral salt with urea in the rainy season/Protein supplement (1 g/kg of body weight) in the dry season; 3 Protein supplement (1 g/kg body weight) in the rainy season/Protein supplement (2 g/kg body weight) in the dry season. 4 Standard deviation of the mean; 5 Means followed by letters differ statistically at a 5% probability level using Tukey’s test.
Table 9.
Fatty acid composition (g/100 g) of meat (Longissimus dorsi) from steers finished with supplement-reduction strategies on tropical pasture.
Table 9.
Fatty acid composition (g/100 g) of meat (Longissimus dorsi) from steers finished with supplement-reduction strategies on tropical pasture.
| Supplementation Strategy | SEM 4 | p-Value 5 | |||
|---|---|---|---|---|---|
| MS/US 1 | US/PS1 2 | PS1/PS2 3 | |||
| Saturated fatty acids (SFA) | |||||
| C6:0 | 0.02 | 0.02 | 0.03 | 0.006 | 0.6410 |
| C8:0 | 0.01 | 0.01 | 0.01 | 0.003 | 0.3349 |
| C10:0 | 0.06 | 0.05 | 0.06 | 0.012 | 0.8712 |
| C12:0 | 0.07 | 0.07 | 0.08 | 0.014 | 0.5080 |
| C14:0 | 2.69 | 2.70 | 2.37 | 0.457 | 0.4544 |
| C15:0 | 0.54 | 0.59 | 0.57 | 0.068 | 0.0608 |
| C16:0 | 23.60 | 24.53 | 24.30 | 1.753 | 0.3058 |
| C17:0 | 1.31 | 1.32 | 1.31 | 0.090 | 0.0660 |
| C18:0 | 23.66 | 24.76 | 24.66 | 6.757 | 0.0585 |
| C20:0 | 1.98 a | 1.35 b | 1.43 b | 0.325 | 0.0359 |
| C21:0 | 0.05 | 0.06 | 0.06 | 0.010 | 0.0878 |
| C22:0 | 0.14 | 0.14 | 0.13 | 0.039 | 0.8960 |
| C24:0 | 0.04 a | 0.02 b | 0.02 b | 0.013 | 0.0176 |
| ∑SFA | 54.17 | 55.62 | 55.03 | 2.610 | 0.2585 |
| Monounsaturated fatty acids (MUFA) | |||||
| C14:1 | 0.46 a | 0.33 b | 0.28b | 0.073 | 0.0217 |
| C15:1 | 0.26 b | 0.32 a | 0.34a | 0.037 | 0.0146 |
| C16:1 | 2.94 | 2.95 | 3.10 | 0.556 | 0.0888 |
| C17:1 | 0.65 | 0.65 | 0.64 | 0.054 | 0.9214 |
| C18:1n9t | 2.58 b | 2.93 ab | 3.36 a | 0.385 | 0.0229 |
| C18:1n9c | 34.91 a | 33.48 b | 33.39 b | 2.534 | 0.0382 |
| C20:1 | 0.18 | 0.19 | 0.18 | 0.034 | 0.8872 |
| C22:1n9 | 0.04 | 0.03 | 0.04 | 0.013 | 0.3904 |
| C24:1 | 0.23 | 0.24 | 0.30 | 0.061 | 0.9520 |
| ∑MUFA | 42.25 | 41.12 | 41.63 | 2.563 | 0.3749 |
| Polyunsaturated fatty acids (PUFA) | |||||
| C18:2n6t | 0.14 | 0.14 | 0.15 | 0.015 | 0.1079 |
| C18:2n6c | 0.35 | 0.35 | 0.35 | 0.058 | 0.9775 |
| C18:3n6 | 0.18 | 0.17 | 0.17 | 0.024 | 0.4109 |
| C18:3n3 | 0.70 a | 0.53 b | 0.52 b | 0.075 | 0.0039 |
| C18:2c9t11 | 0.51 a | 0.42 b | 0.38 b | 0.045 | 0.0459 |
| C18:2t10c12 | 0.12 a | 0.10 b | 0.10 b | 0.013 | 0.0370 |
| C20:2 | 0.05 | 0.04 | 0.04 | 0.010 | 0.0659 |
| C20:3n6 | 0.11 | 0.11 | 0.10 | 0.022 | 0.6129 |
| C20:4n6 | 0.82 b | 0.93 b | 1.09 a | 0.182 | 0.0040 |
| C22:2 | 0.28 | 0.28 | 0.27 | 0.095 | 0.9171 |
| C20:5n3 | 0.28 a | 0.15 b | 0.14 b | 0.058 | 0.0040 |
| C22:6n3 | 0.04 | 0.04 | 0.03 | 0.010 | 0.0467 |
| ∑PUFA | 3.58 a | 3.26 b | 3.34 b | 0.218 | 0.0153 |
1 Mineral salt ad libitum in the rainy season/Mineral salt with urea in the dry season; 2 Mineral salt with urea in the rainy season/Protein supplement (1 g/kg of body weight) in the dry season; 3 Protein supplement (1 g/kg body weight) in the rainy season/Protein supplement (2 g/kg body weight) in the dry season. 4 Standard deviation of the mean; 5 Means followed by letters differ statistically at a 5% probability level using Tukey’s test.
Table 10.
Nutritional quality indices and desaturase activity indices of meat (Longissimus dorsi) from steers finished with supplement-reduction strategies on tropical pasture.
Table 10.
Nutritional quality indices and desaturase activity indices of meat (Longissimus dorsi) from steers finished with supplement-reduction strategies on tropical pasture.
| Supplementation Strategy | SEM 4 | p-Value 5 | |||
|---|---|---|---|---|---|
| MS/US 1 | US/PS1 2 | PS1/PS2 3 | |||
| MUFA:SFA 6 | 0.78 | 0.74 | 0.76 | 0.090 | 0.3455 |
| PUFA:SFA 7 | 0.07 | 0.06 | 0.06 | 0.005 | 0.1745 |
| DFA 8 | 69.49 | 69.14 | 69.63 | 2.145 | 0.6815 |
| Atherogenicity index | 0.77 | 0.81 | 0.77 | 0.101 | 0.5509 |
| Thrombogenicity index | 1.88 | 2.00 | 1.94 | 0.165 | 0.0949 |
| h:H 9 | 1.51 | 1.41 | 1.46 | 0.187 | 0.5035 |
| ∑ ω-6 (n-6) fatty acids | 1.60 b | 1.70 b | 1.86 a | 0.214 | 0.0118 |
| ∑ ω-3 (n-3) fatty acids | 1.02 a | 0.72 b | 0.69 b | 0.100 | 0.0003 |
| n-6:n-3 | 1.57 b | 2.36 a | 2.69 a | 0.465 | 0.0031 |
| Δ9 desaturase 14 | 14.60 a | 10.89 b | 10.56 b | 1.563 | 0.0100 |
| Δ9 desaturase 16 | 11.07 | 10.73 | 11.35 | 1.041 | 0.3488 |
| Δ9 desaturase 18 | 59.60 a | 57.48 b | 57.52 b | 2.974 | 0.0349 |
1 Mineral salt ad libitum in the rainy season/Mineral salt with urea in the dry season; 2 Mineral salt with urea in the rainy season/Protein supplement (1 g/kg of body weight) in the dry season; 3 Protein supplement (1 g/kg body weight) in the rainy season/Protein supplement (2 g/kg body weight) in the dry season. 4 Standard deviation of the mean; 5 Means followed by letters differ statistically at a 5% probability level using Tukey’s test. 6 Ratio of monounsaturated to saturated fatty acids; 7 Ratio of polyunsaturated to saturated fatty acids; 8 Desirable fatty acids; 9 Ratio of hypocholesterolemic to hypercholesterolemic fatty acids.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. |
© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
MDPI and ACS Style
Cediel-Devia, D.C.; Schaitz, L.H.; da Silva, F.F.; Santos, L.V.; da Silva, A.P.G.; Santos, M.d.C.; Dueñez, W.Y.S.; Melgar, O.R.A.; Paixão, T.R.; Silva, J.W.D.; et al. Performance, Carcass Traits, and Meat Fatty Acid Profile of Post-Weaning and Finishing Zebu Steers on Tropical Pasture with Three Low-Intake Supplementation Strategies. Animals 2024, 14, 2486. https://doi.org/10.3390/ani14172486
AMA Style
Cediel-Devia DC, Schaitz LH, da Silva FF, Santos LV, da Silva APG, Santos MdC, Dueñez WYS, Melgar ORA, Paixão TR, Silva JWD, et al. Performance, Carcass Traits, and Meat Fatty Acid Profile of Post-Weaning and Finishing Zebu Steers on Tropical Pasture with Three Low-Intake Supplementation Strategies. Animals. 2024; 14(17):2486. https://doi.org/10.3390/ani14172486
Chicago/Turabian StyleCediel-Devia, Diana Carolina, Luís Henrique Schaitz, Fabiano Ferreira da Silva, Laize Vieira Santos, Ana Paula Gomes da Silva, Marceliana da Conceição Santos, Wbeimar Yamit Sanchez Dueñez, Osman Ronaldo Aguilar Melgar, Tarcísio Ribeiro Paixão, João Wilian Dias Silva, and et al. 2024. "Performance, Carcass Traits, and Meat Fatty Acid Profile of Post-Weaning and Finishing Zebu Steers on Tropical Pasture with Three Low-Intake Supplementation Strategies" Animals 14, no. 17: 2486. https://doi.org/10.3390/ani14172486
APA StyleCediel-Devia, D. C., Schaitz, L. H., da Silva, F. F., Santos, L. V., da Silva, A. P. G., Santos, M. d. C., Dueñez, W. Y. S., Melgar, O. R. A., Paixão, T. R., Silva, J. W. D., de Araújo, T. L. A. C., de Lima Júnior, D. M., & Silva, R. R. (2024). Performance, Carcass Traits, and Meat Fatty Acid Profile of Post-Weaning and Finishing Zebu Steers on Tropical Pasture with Three Low-Intake Supplementation Strategies. Animals, 14(17), 2486. https://doi.org/10.3390/ani14172486
Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.
