da Silva Aline Gomes, Paulino Mário Fonseca, da Silva Amorim Lincoln, Rennó Luciana Navajas, Detmann Edenio, de Moura Felipe Henrique, Manso Marcos Rocha, Silva E Paiva Paulo Henrique, Ortega Román Enrique Maza, de Melo Luciano Prímola
Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-000, Brazil.
Biotran - Biotecnologia e Treinamento em Reprodução Animal, Alfenas, Minas Gerais, 37130-000, Brazil.
Trop Anim Health Prod. 2017 Apr;49(4):707-715. doi: 10.1007/s11250-017-1248-1. Epub 2017 Feb 11.
The present study was conducted to evaluate the effects of high and low supplementation levels pre- and post-weaning on performance, endocrine, metabolic, and reproductive responses of Nellore heifers. Fifty Nellore heifers with 132 ± 9.9 kg average body weight (BW) and 138 ± 19 days of age were supplemented from 4 to 14 months. The heifers were distributed into five supplementation plans: HH-6 g/kg of BW of supplement pre- and post-weaning, HL-6 g/kg of BW of supplement pre-weaning and 3 g/kg post-weaning, LH-3 g/kg of BW pre-weaning and 6 g/kg of BW post-weaning, LL-3 g/kg of BW pre- and post-weaning, and CC-control, no supplementation. Interactions were not significant (P > 0.10). The level of supplement fed pre-weaning did not affect any of the performance variables evaluated at the end of the experiment (P > 0.10). There was a significant effect of supplementation and level of supplementation fed post-weaning on average daily gain (ADG) and final BW (P < 0.05). Overall ADG was also affected only by supplementation and level of supplement fed post-weaning (P < 0.05) with animals receiving 6 g/kg of BW post-weaning gaining more weight. Follicular diameter was greater in animals that received 6 g/kg of BW post-weaning (P < 0.05). In summary, performance, endocrine, metabolic, and reproductive variables evaluated in the current study were improved by the level of supplement fed post-weaning. Heifers receiving supplementation of 6 g/kg of BW post-weaning had greater responses, independent of the level received during the pre-weaning phase.
本研究旨在评估断奶前后不同高低水平补饲对内洛尔小母牛生长性能、内分泌、代谢及繁殖反应的影响。选取50头平均体重132±9.9千克、年龄138±19天的内洛尔小母牛，从4月龄至14月龄进行补饲。小母牛被分为五个补饲方案：HH组，断奶前后均按6克/千克体重补饲；HL组，断奶前按6克/千克体重补饲，断奶后按3克/千克体重补饲；LH组，断奶前按3克/千克体重补饲，断奶后按6克/千克体重补饲；LL组，断奶前后均按3克/千克体重补饲；CC组为对照组，不进行补饲。交互作用不显著（P＞0.10）。断奶前补饲水平对实验结束时评估的任何生长性能变量均无影响（P＞0.10）。断奶后补饲及补饲水平对平均日增重（ADG）和最终体重有显著影响（P＜0.05）。总体ADG也仅受断奶后补饲及补饲水平影响（P＜0.05），断奶后接受6克/千克体重补饲的动物增重更多。断奶后接受6克/千克体重补饲的动物卵泡直径更大（P＜0.05）。总之，本研究中评估的生长性能、内分泌、代谢及繁殖变量因断奶后补饲水平而得到改善。断奶后接受6克/千克体重补饲的小母牛反应更大，与断奶前阶段的补饲水平无关。
