Institute of Animal Breeding and Genetics, University of Giessen, Ludwig St. 21B, 35390 Giessen, Germany.
Institute of Animal Breeding and Genetics, University of Giessen, Ludwig St. 21B, 35390 Giessen, Germany.
Animal. 2021 Mar;15(3):100034. doi: 10.1016/j.animal.2020.100034. Epub 2021 Feb 15.
In sheep production, economic efficiency strongly depends on the maternal health and feed efficiency status and on weaning performances of their offspring. Accordingly, an optimal level for the supply with macro- and microelements and the ewe energy status has impact on the fetal development during gestation and on maternal milk production during lactation. Furthermore, this study addressed intergenerational aspects, i.e., on associations between maternal energy metabolism profiles considering the macro- and microelement status, metabolic indicators (e.g. β-hydroxybutyrate (BHB)), body condition and methane (CH4) emissions with lamb BW (LBW) in two sheep breeds. Traits were recorded at the beginning of gestation (ewe traits), at lambing, three weeks postpartum, and at weaning (ewe and lamb traits). Trait recording included CH4 emissions (recorded via laser methane detector (LMD)), ewe BW (EBW), backfat thickness (BFT), and body condition score (BCS) from 46 ewes (24 Merinoland- (ML), 22 Rhönsheep (RH)), and LBW of their 87 (35 ML, 52 RH) purebred lambs. Serum levels of the following ewe blood parameters were determined: calcium (Ca), sodium (Na), potassium (K), phosphate (P), nonesterified fatty acids (NEFA), BHB, glutamate dehydrogenase (GLDH), selenium (Se), copper (Cu), iron (Fe), zinc (Zn), and magnesium (Mg). Mixed models were applied to infer associations between ewe blood parameters with EBW, BFT, BCS, and CH4 and with LBW recorded in offspring. At weaning, a maternal serum Mg level > 1.0 mmol/L was significantly associated with an increase of 13% in LBW in ML, compared to offspring from ML ewes with a serum Mg concentration within the lower reference range (0.8 mmol/L). Furthermore, higher Cu levels were favorably associated with ewe BCS and BFT at weaning in both breeds. In RH ewes, a Se level > 2.4 μmol/l was significantly associated with increased BCS. In the ML breed, high Zn levels during lactation were associated with reduced CH4 emissions. Ewe EBW was significantly larger for ML ewes representing low Ca levels. A low BHB level was associated with decreasing CH4 emissions in RH and ML. Serum levels for Na, K, P, GLDH, and Fe did not significantly affect the traits of interest. Trait associations from the present study indicate the importance of the mineral supply and metabolic status of the ewe with regard to body condition, CH4 emissions, and LBW development, but depending on the breed. Identified associations might contribute to energy efficiency in sheep production systems.
在绵羊生产中，经济效益很大程度上取决于母羊的健康和饲料效率状况以及其后代的断奶性能。因此，宏量和微量元素以及母羊能量状况的最佳供应水平对胎儿在妊娠期的发育和哺乳期的母羊奶生产有影响。此外，本研究还涉及代际方面，即考虑到宏量和微量元素状况、代谢指标（例如β-羟丁酸（BHB））、体况和甲烷（CH4）排放与两种绵羊品种母羊的羔羊体重（LBW）之间的关系。在妊娠开始时（母羊性状）、分娩时、产后 3 周和断奶时（母羊和羔羊性状）记录性状。性状记录包括 CH4 排放（通过激光甲烷探测器（LMD）记录）、母羊体重（EBW）、背膘厚度（BFT）和体况评分（BCS），来自 46 只母羊（24 只 Merinoland-（ML），22 只 Rhönsheep（RH）），以及它们 87 只（35 只 ML，52 只 RH）纯种羔羊的 LBW。测定了以下母羊血液参数的血清水平：钙（Ca）、钠（Na）、钾（K）、磷（P）、非酯化脂肪酸（NEFA）、BHB、谷氨酸脱氢酶（GLDH）、硒（Se）、铜（Cu）、铁（Fe）、锌（Zn）和镁（Mg）。应用混合模型推断母羊血液参数与 EBW、BFT、BCS 和 CH4 以及后代记录的 LBW 之间的关系。在断奶时，ML 母羊的血清 Mg 水平 > 1.0mmol/L 与 LBW 增加 13%显著相关，与血清 Mg 浓度处于较低参考范围（0.8mmol/L）的 ML 母羊的后代相比。此外，较高的 Cu 水平与两种品种的母羊断奶时的 BCS 和 BFT 呈正相关。在 RH 母羊中，血清 Se 水平 > 2.4µmol/L 与 BCS 增加显著相关。在 ML 品种中，哺乳期高 Zn 水平与 CH4 排放减少有关。代表低 Ca 水平的 ML 母羊的 EBW 明显更大。低 BHB 水平与 RH 和 ML 中 CH4 排放的减少有关。Na、K、P、GLDH 和 Fe 的血清水平与感兴趣的性状没有显著影响。本研究的性状关联表明，母羊的矿物质供应和代谢状况对体况、CH4 排放和 LBW 发育很重要，但取决于品种。确定的关联可能有助于绵羊生产系统的能量效率。
