Department of Animal and Range Sciences, New Mexico State University, Las Cruces 88003, USA.
J Anim Sci. 2012 Dec;90(13):5099-106. doi: 10.2527/jas.2012-5535. Epub 2012 Jul 31.
A 4-yr study was conducted at Corona Range and Livestock Research Center, Corona, NM, to establish if a protein-dense self-fed supplement could substitute for a traditional hand-fed (range cube) supplement that is less protein dense and minimize or maintain cow BW and BCS during late gestation and the subsequent steer progeny feedlot performance, health, and economic viability. Late gestation cows received one of 3 supplementation strategies: 1) 36% CP cottonseed meal base supplement (CSM; positive control) fed 3 times per week, 2) self-fed supplement (SMP) comprising 50% animal protein sources (blood meal and feather meal) and 50% trace mineral package, or 3) brief and intermittent supplementation of CSM based on periods of acute environmental stress (VAR; negative control) by ranch management. Initiation of supplementation varied across years due to changing forage conditions and climatically imposed grazing constraints but always ended approximately 2 wks before calving each year. Across all 4 yr, supplement consumption averaged 0.65, 0.21, and 0.04 kg·head(-1)·d(-1) for CSM, SMP, and VAR, respectively. After weaning, steers were preconditioned for 45 d and were received and treated as custom fed commercial cattle at a feedlot in mid November each year. Cow BW and BCS were not influenced (P ≥ 0.13) by prepartum supplementation; however, the strategy did have an effect on BW and BCS change with cows managed in the VAR group. Cows managed in the VAR group lost the greatest (P < 0.05) amount of BW and BCS whereas no differences were measured between CSM and SMP groups. Prepartum supplementation strategies did not influence (P = 0.98) pregnancy rates. Calf weaning, initial feedlot and final BW, and HCW were unaffected (P ≥ 0.80) by prepartum supplementation of the dam. Steers from dams fed CSM and VAR had a greater percentage treated for sickness than SMP steers (P = 0.03), which resulted in a tendency (P = 0.07) for medicine costs to be greater in steers from CSM and VAR cows. The use of a self-fed package supplement was equally effective as use of a traditional hand-fed, oilseed-based supplement in maintaining BW and BCS during late gestation. In addition, these results imply that although nutrition treatment of cows during the prenatal period had no effect on calf growth performance, calves from cows fed SMP had improved feedlot health.
一项为期 4 年的研究在新墨西哥州科罗纳牧场和牲畜研究中心进行，旨在确定高蛋白自饲补充剂是否可以替代传统的手喂（牧场立方体）补充剂，这种补充剂的蛋白质密度较低，并在妊娠后期最小化或维持奶牛体重和体况（BCS），以及随后的育肥牛肥育场性能、健康和经济可行性。妊娠后期奶牛接受了 3 种补充策略之一：1）36%CP 棉籽粉基础补充剂（CSM；阳性对照）每周喂 3 次，2）自饲补充剂（SMP）由 50%动物蛋白源（血粉和羽毛粉）和 50%微量矿物质包组成，或 3）根据牧场管理的急性环境应激（VAR；阴性对照）进行短暂和间歇性的 CSM 补充。由于饲料条件的变化和气候限制放牧，每年的补充开始时间都不同，但每年都在大约 2 周前结束产前补充。在所有 4 年中，CSM、SMP 和 VAR 的补充剂消耗量分别平均为 0.65、0.21 和 0.04kg·头(-1)·d(-1)。断奶后，育肥牛经过 45 天的预处理，并于每年 11 月中旬在肥育场以定制喂养的商业牛的形式进行接收和处理。产前补充对奶牛的体重和体况（BCS）没有影响（P≥0.13）；然而，这种策略确实对 VAR 组管理的奶牛的体重和 BCS 变化有影响。在 VAR 组管理的奶牛中，体重和 BCS 的损失最大（P<0.05），而 CSM 和 SMP 组之间没有差异。产前补充策略对妊娠率没有影响（P=0.98）。犊牛断奶、初始肥育场和最终体重以及 HCW 不受产前母畜补充的影响（P≥0.80）。与 SMP 育肥牛相比，饲喂 CSM 和 VAR 的育肥牛有更高的患病治疗比例（P=0.03），这导致 CSM 和 VAR 奶牛的育肥牛药物费用有增加的趋势（P=0.07）。使用自饲包补充剂与使用传统的手喂、油籽基补充剂在妊娠后期维持体重和体况方面同样有效。此外，这些结果表明，尽管在产前期间对奶牛的营养处理对犊牛的生长性能没有影响，但饲喂 SMP 的犊牛在肥育场的健康状况有所改善。
