Department of Animal Nutrition and Production, University of Sao Paulo, Pirassununga, Brazil, 13635-900.
Department of Animal Nutrition and Production, University of Sao Paulo, Pirassununga, Brazil, 13635-900; Bursar 1-C of the National Council of Scientific and Technologic Development, Brasilia, Brazil, 716055-001.
J Dairy Sci. 2018 Jan;101(1):675-689. doi: 10.3168/jds.2016-12504. Epub 2017 Nov 6.
The objective of this study was to evaluate different durations of whole raw soybeans (WS) supplementation during the prepartum period on nutrient digestibility, milk yield and composition, energy balance, blood metabolites, and oocyte and embryo quality of transition cows. Thirty-one Holstein cows were used in a completely randomized design and assigned to 4 experimental groups (G): G90, G60, G30, and G0 (control), supplemented with a diet containing 12% of WS from 90, 60, 30, and 0 d relative to the calving date, respectively. Cows were dried off 60 d before the expected calving date. After parturition, all cows were fed a diet containing 12% of WS until 84 DIM. Blood samples were collected on d -49, -35, -21, -14, -7, 0, 7, 14, 21, 35, and 70 relative to partum. Ovum pick-ups were performed on d 21 ± 3, 42 ± 7, 63 ± 7, and 84 ± 7 of lactation. Different durations of WS supplementation did not affect DMI and apparent total-tract digestibility in either the pre- or postpartum periods. Duration of WS supplementation had no effect on milk yield and composition nor energy balance of cows. However, the duration of WS supplementation had several effects on milk fatty acid (FA) profile of cows, including a linear decrease in concentrations of cis-9 C18:1, unsaturated C18, total monounsaturated, and unsaturated FA. Further, the milk contents of cis-9,cis-12 C18:2 FA, cis-9,trans-11 C18:2 FA, and total polyunsaturated FA were increased when WS were fed to cows from 30 d but not from 60 or 90 d of the expected calving date. The length of WS supplementation in the prepartum period linearly increased blood cholesterol concentration of cows during the prepartum period, but it had no effect on blood glucose and nonesterified FA concentrations in the pre- and postpartum periods. Duration of WS supplementation during the prepartum period increased the average number of grade 2 oocytes, notably in G60, but it had no effect on embryo production and cleavage proportion of early-lactation cows. The duration of WS supplementation in the prepartum period had no effect on milk yield and energy balance of the subsequent lactation, but it altered milk FA profile in early lactation by decreasing unsaturated FA content, notably when starting to supplement WS at 90 and 60 d from the expected calving date. Our results also showed that the duration of WS supplementation during the prepartum period does not improve oocyte quality in the subsequent lactation of cows.
本研究旨在评估围产前不同时长的全豆（WS）添加对围产前期和后期奶牛的养分消化率、产奶量和组成、能量平衡、血液代谢物以及卵母细胞和胚胎质量的影响。31 头荷斯坦奶牛采用完全随机设计，分为 4 个实验组（G）：G90、G60、G30 和 G0（对照组），分别从预产期前 90、60、30 和 0 天开始添加含 12%WS 的日粮。奶牛在预产期前 60 天干奶。产后，所有奶牛均饲喂含 12%WS 的日粮，直至第 84 天泌乳期结束。分娩前 49、35、21、14、7、0、7、14、21、35 和 70 天采集血样。产后第 21、42、63 和 84 天进行卵母细胞采集。WS 添加时长对预产前期和后期奶牛的干物质采食量和表观全肠道消化率均无影响。WS 添加时长对奶牛的产奶量和组成以及能量平衡没有影响。然而，WS 添加时长对奶牛的乳脂肪酸（FA）谱有多种影响，包括顺式-9 C18:1、不饱和 C18、总单不饱和和不饱和 FA 的浓度线性降低。此外，从预产期前 30 天开始饲喂 WS 会增加乳中顺式-9,顺式-12 C18:2 FA、顺式-9,反式-11 C18:2 FA 和总多不饱和 FA 的含量，但从 60 天或 90 天开始则没有这种效果。围产前期 WS 添加时长呈线性增加奶牛的血液胆固醇浓度，但对预产前期和后期的血糖和非酯化脂肪酸浓度没有影响。围产前期 WS 添加时长增加了 G60 中等级 2 卵母细胞的平均数量，但对产后奶牛的胚胎产量和卵裂比例没有影响。围产前期 WS 添加时长对随后泌乳期的产奶量和能量平衡没有影响，但通过降低不饱和 FA 含量改变了早期泌乳期的乳 FA 谱，尤其是从预产期前 90 天和 60 天开始添加 WS 时。我们的结果还表明，围产前期 WS 添加时长不会改善奶牛随后泌乳期的卵母细胞质量。
