Nouri M, Zarrin M, Ahmadpour A, Castro N, González-Cabrera M, Hernández-Castellano Lorenzo E
Department of Animal Science, Faculty of Agriculture, Yasouj University, Student Street, 75918-74831, Yasouj, I. R. Iran.
Department of Animal Science, Faculty of Agriculture, Yasouj University, Student Street, 75918-74831, Yasouj, I. R. Iran.
J Dairy Sci. 2023 Apr;106(4):2980-2988. doi: 10.3168/jds.2022-22505. Epub 2023 Mar 2.
This study aimed to investigate the effect of prepartum and postpartum feed restriction of fat-tailed dairy sheep on colostrum IgG concentration, and performance and blood metabolites of newborn fat-tailed lambs. Twenty fat-tailed dairy sheep were randomly allocated into control (Ctrl; n = 10) and feed restriction (FR; n = 10) groups. The Ctrl group received a diet that met 100% of energy requirements, both prepartum (from wk -5 to parturition) and postpartum (from parturition to wk 5). The FR group received a diet equivalent to 100, 50, 65, 80, and 100% of the energy requirements in wk -5, -4, -3, -2, and -1 relative to parturition, respectively. After parturition, the FR group received a diet equivalent to the 100, 50, 65, 80, and 100% of the energy requirements in wk 1, 2, 3, 4, and 5, respectively. At birth, lambs were assigned to their dam's experimental group. Both the Ctrl lambs (n = 10) and the FR lambs (n = 10) were allowed to suck colostrum and milk from the dams. Colostrum samples (50 mL) were collected at parturition (0 h) and then at 1, 12, 24, 36, 48, and 72 h postpartum. Blood samples were collected from all lambs before suckling colostrum (0 h) and then at 1, 12, 24, 36, 48, and 72 h after birth and weekly until the end of the experimental period (i.e., wk 5 relative to birth). The data were evaluated using the MIXED procedure of SAS (SAS Institute Inc.). The model included feed restriction, time, and the interaction feed restriction × time as fixed effects. The individual lamb was set as a repeated subject. Variables measured in colostrum and plasma were considered dependent variables, and significance was set at P < 0.05. Prepartum and postpartum feed restriction in fat-tailed dairy sheep did not affect colostrum IgG concentration. Consequently, no differences in blood IgG concentrations were observed in the lambs. In addition, the prepartum and postpartum feed restriction experienced by fat-tailed dairy sheep caused decreased body weight and milk intake in lambs from the FR group compared with the Ctrl group. Feed restriction also promoted increased concentration of blood metabolites such as triglycerides and urea in FR lambs compared with control lambs. In conclusion, prepartum and postpartum feed restriction in fat-tailed dairy sheep did not affect either colostrum IgG concentration or blood IgG concentration of the lambs. However, prepartum and postpartum feed restriction decreased lamb milk intake and, therefore, lamb body weight gain during the first 5 wk after birth.
本研究旨在探讨产前和产后限制肥尾奶羊采食量对初乳免疫球蛋白G（IgG）浓度、新生肥尾羔羊生产性能及血液代谢产物的影响。将20只肥尾奶羊随机分为对照组（Ctrl；n = 10）和限饲组（FR；n = 10）。对照组在产前（从妊娠第-5周到分娩）和产后（从分娩到第5周）均采食满足100%能量需求的日粮。限饲组在产前相对于分娩的第-5、-4、-3、-2和-1周分别采食相当于能量需求100%、50%、65%、80%和100%的日粮。分娩后，限饲组在产后第1、2、3、4和5周分别采食相当于能量需求100%、50%、65%、80%和100%的日粮。出生时，羔羊被分配到其母羊所在的实验组。对照组羔羊（n = 10）和限饲组羔羊（n = 10）均允许吸食母羊的初乳和乳汁。在分娩时（0小时）以及产后1、12、24、36、48和72小时采集初乳样本（50毫升）。在所有羔羊吸食初乳前（0小时）以及出生后1、12、24、36、48和72小时采集血样，并每周采集一次，直至实验期结束（即相对于出生的第5周）。使用SAS（SAS Institute Inc.）的MIXED程序对数据进行评估。模型将限饲、时间以及限饲×时间的交互作用作为固定效应。将每只羔羊设定为重复观测对象。将初乳和血浆中测量的变量视为因变量，显著性水平设定为P < 0.05。产前和产后限制肥尾奶羊采食量对初乳IgG浓度没有影响。因此，在羔羊中未观察到血液IgG浓度的差异。此外，与对照组相比，肥尾奶羊产前和产后采食量受限导致限饲组羔羊体重和采奶量下降。与对照组羔羊相比，限饲还使限饲组羔羊血液中甘油三酯和尿素等代谢产物浓度升高。总之，产前和产后限制肥尾奶羊采食量对羔羊的初乳IgG浓度或血液IgG浓度均无影响。然而，产前和产后采食量受限会降低羔羊的采奶量，从而导致出生后前5周羔羊体重增加减少。
