Valle Felipe R A F, Fontes Carlos A A, Fernandes Alberto M, Oliveira Tadeu S, Processi Elizabeth F, Silva Renata S T
Laboratory of Animal Science, Campos dos Goytacazes, RJ, 28013-602, Brazil.
Federal Rural University of Rio de Janeiro, Campos dos Goytacazes, RJ, 28022-560, Brazil.
Trop Anim Health Prod. 2020 Sep;52(5):2491-2498. doi: 10.1007/s11250-020-02278-7. Epub 2020 May 4.
The use of additional supplement can affect ruminant performance by increasing the animal weight gain and maximizing profits from the activity. Thus, the objective of this study was to evaluate the influence of protein-energy supplementation on microbial synthesis, animal performance, nutrient digestibility, and body composition of Brangus x Zebu steers on pasture. The experiment lasted 160 days and included 36 animals divided into two groups; 18 steers received protein-energy supplementation (PES), and the other 18 received non-supplementation (NPES). Individual pasture intake and nutrient digestibility were estimated using the double indicator technique-chromium oxide and lignin in potassium permanganate. Spot urine samples were collected from 36 animals to determine creatinine, allantoin, and uric acid concentrations. All animals were slaughtered at the end of the experiment to evaluate body composition. There was increase in intake (P < 0.001) and dry matter digestibility (P = 0.01); it resulted in higher animal weight gain (P < 0.001) receiving supplementation. However, there was no difference (P > 0.05) in pasture nutrient intake between treatments. Supplementation increased microbial nitrogen (P < 0.001). For body composition, the model identity test that was applied showed no difference (P > 0.05) between the models, so it was adopted a common equation for both treatments. There was no difference (P > 0.05) for body composition between treatments. Therefore, the use of protein-energy supplementation for steers on pasture allowed higher microbial protein synthesis and better utilization of nutrients, which resulted in better animal performance. The use of protein-energy supplementation at 0.6% BW did not alter the carcass composition of Brangus x Zebu steers. However, it recommends protein-energy supplementation in pasture systems during the rainy period or using an irrigation system.
使用额外的补充剂可以通过增加动物体重增加和使该活动的利润最大化来影响反刍动物的生产性能。因此，本研究的目的是评估蛋白质-能量补充对放牧的婆罗门牛×瘤牛阉牛的微生物合成、动物生产性能、养分消化率和身体组成的影响。实验持续了160天，包括36头动物，分为两组；18头阉牛接受蛋白质-能量补充（PES），另外18头接受不补充（NPES）。使用双指示剂技术——氧化铬和高锰酸钾中的木质素估计个体牧场采食量和养分消化率。从36头动物中采集即时尿液样本以测定肌酐、尿囊素和尿酸浓度。所有动物在实验结束时被屠宰以评估身体组成。采食量（P < 0.001）和干物质消化率增加（P = 0.01）；接受补充的动物体重增加更高（P < 0.001）。然而，处理之间牧场养分摄入量没有差异（P > 0.05）。补充增加了微生物氮（P < 0.001）。对于身体组成，所应用的模型同一性检验表明模型之间没有差异（P > 0.05），因此对两种处理采用了共同的方程。处理之间身体组成没有差异（P > 0.05）。因此，对放牧阉牛使用蛋白质-能量补充剂可实现更高的微生物蛋白质合成和更好的养分利用，从而带来更好的动物生产性能。以体重的0.6%使用蛋白质-能量补充剂不会改变婆罗门牛×瘤牛阉牛的胴体组成。然而，建议在雨季或使用灌溉系统的牧场系统中进行蛋白质-能量补充。
