Alves A C, Alves N G, Ascari I J, Junqueira F B, Coutinho A S, Lima R R, Pérez J R O, De Paula S O, Furusho-Garcia I F, Abreu L R
Department of Veterinary Medicine, Federal University of Lavras, Lavras, 37200-000, Minas Gerais, Brazil.
Department of Veterinary Medicine, Federal University of Lavras, Lavras, 37200-000, Minas Gerais, Brazil; Department of Animal Science, Federal University of Lavras, Lavras, 37200-000, Minas Gerais, Brazil.
J Dairy Sci. 2015 Jun;98(6):3706-16. doi: 10.3168/jds.2014-7992. Epub 2015 Mar 28.
This study aimed to analyze the chemical composition and the IgG concentration of the colostrum, transitional milk, and mature milk of Santa Inês ewes as well as the transfer of passive immunity to lambs. Thirty-two pregnant ewes and 38 lambs were used. Ewes were milked immediately after lambing and at 12, 24, 36 h and 10 d postpartum. Colostrum was provided to the lambs at 40±15 min (mean±SE) after birth and then at 30-min intervals for obtaining the intake closest to 10% of body weight, and transitional milk was provided ad libitum. Blood from the lambs was collected 36 h after birth for measuring the serum concentrations of IgG, total protein, albumin, and gamma-globulin. The production was lower in primiparous than in multiparous ewes with body condition score (BCS)<2.75, but did not differ between primiparous and multiparous with BCS≥2.75 (interaction parity and BCS). The IgG concentration and fat, protein, lactose, and defatted dry extract percentages were not affected by the BCS of the ewe at lambing or by the parity. The total solids percentage in the colostrum was higher in ewes with BCS<2.75 (interaction BCS and time). The production and the protein, total solid, and defatted dry extract percentages showed quadratic behavior, the fat percentage decreased linearly, and the lactose percentage increased linearly with time postpartum. The IgG concentration in the colostrum was not correlated with the ewe's weight or BCS at the time of lambing. Moreover, the parity, the BCS, the ewe's type of gestation, and the lamb's sex did not influence the serum concentrations of IgG, total protein, albumin, and gamma-globulin in lambs. Adequate passive immune transfer (PIT) was observed in lambs for which the IgG intake was higher than 30 g. Failure in PIT was observed in 39.5% of lambs when considering a serum IgG concentration lower than 15 mg/mL and in 21% when considering a serum total protein concentration lower than 45 mg/mL. The mean apparent efficiency of absorption was 38.10%, with values between 0.02% and 98.80%. The serum IgG concentration was correlated with the total protein concentration (according to the enzymatic colorimetric method), the gamma-globulin concentration, and the absorption efficiency. The extreme variation on apparent efficiency of absorption may have an effect on the success of PIT. Lambs should consume at least 30 g of IgG in the first 24 h of life to ensure adequate PIT.
本研究旨在分析圣伊内斯母羊初乳、过渡乳和成熟乳的化学成分及IgG浓度，以及向羔羊的被动免疫转移情况。使用了32只怀孕母羊和38只羔羊。母羊在产羔后以及产后12、24、36小时和10天立即挤奶。羔羊在出生后40±15分钟（平均值±标准误）时开始喂食初乳，然后每隔30分钟喂食一次，以使摄入量最接近体重的10%，过渡乳则随意提供。在羔羊出生36小时后采集血液，以测量血清中IgG、总蛋白、白蛋白和γ-球蛋白的浓度。初产且体况评分（BCS）<2.75的母羊产奶量低于经产母羊，但BCS≥2.75的初产母羊和经产母羊之间产奶量无差异（产次与BCS的交互作用）。初乳中IgG浓度以及脂肪、蛋白质、乳糖和脱脂干提取物的百分比不受产羔时母羊BCS或产次的影响。BCS<2.75的母羊初乳中总固体百分比更高（BCS与时间的交互作用）。产奶量以及蛋白质、总固体和脱脂干提取物的百分比呈二次曲线变化，脂肪百分比随产后时间呈线性下降，乳糖百分比随产后时间呈线性增加。初乳中IgG浓度与产羔时母羊的体重或BCS无关。此外，产次、BCS、母羊的妊娠类型以及羔羊的性别均不影响羔羊血清中IgG、总蛋白、白蛋白和γ-球蛋白的浓度。对于IgG摄入量高于30克的羔羊，观察到了充分的被动免疫转移（PIT）。当考虑血清IgG浓度低于15毫克/毫升时，39.5%的羔羊出现PIT失败；当考虑血清总蛋白浓度低于45毫克/毫升时，21%的羔羊出现PIT失败。平均表观吸收效率为38.10%，值在0.02%至98.80%之间。血清IgG浓度与总蛋白浓度（根据酶比色法）、γ-球蛋白浓度以及吸收效率相关。表观吸收效率的极大差异可能会影响PIT的成功。羔羊在出生后的头24小时内应至少摄入30克IgG，以确保充分的PIT。
