Abstract Research on Soay Island sheep showed a positive association of serum 25(OH)D concentration and fecundity, while similar research on Scottish sheep didn’t show an association with fecundity but did show an association with weaned lamb weight. Therefore the aim of this study was to determine if serum 25-hydroxyvitamin D (25(OH)D) concentrations of ewes at mating, on a commercial sheep farm, was associated with subsequent prolificacy. On a sheep and beef farm in the North Island of New Zealand 200 mixed-age Romney ewes (Ovis aries) had weights recorded and blood was collected by jugular venepuncture in April (autumn) at mating. Pregnancy testing was conducted 12 weeks after mating, using real time ultrasound to confirm pregnancy and determine whether the dams were carrying singletons, twins or triplets. Serum 25(OH)D2 and D3 concentrations, total calcium, and phosphorus concentrations were measured in the 200 pregnant ewes. A multinomial logistic regression model was fitted to the data in order to determine significant predictors of the ultrasound scanning result. The mean serum total 25(OH)D concentrations of single, twin and triplet bearing ewes were 102.0 ± 3.4, 101.0 ± 2.4 and 83.0 ± 4.5, respectively. In a multinomial logistic regression model serum total 25(OH)D and 25(OH)D3 concentrations were also negatively correlated with ewes pregnant with triplets (P = 0.015), while weight was significantly associated with both twin and triplet bearing ewes (P The reason for the lower serum 25(OH)D concentration in sheep bearing triplets is unclear, and further research is required in order to determine the mechanisms behind this. The results suggest that an effect on ewe fecundity may only be seen when serum 25(OH)D concentrations are marginal.

中文翻译：

---

血清25-羟基维生素D浓度对新西兰养羊场母羊繁殖力的影响

摘要 对索伊岛绵羊的研究显示血清 25(OH)D 浓度与繁殖力呈正相关，而对苏格兰绵羊的类似研究并未显示与繁殖力相关，但确实显示与断奶羔羊体重相关。因此，本研究的目的是确定在商业养羊场交配时母羊的血清 25-羟基维生素 D (25(OH)D) 浓度是否与随后的多产有关。在新西兰北岛的一个绵羊和牛肉农场，200 头混龄罗姆尼母羊（Ovis aries）在 4 月（秋季）交配时记录了体重并通过颈静脉穿刺收集了血液。交配后 12 周进行妊娠测试，使用实时超声波确认怀孕并确定母鼠是否携带单胎、双胞胎或三胞胎。血清 25(OH)D2 和 D3 浓度，测量了 200 头怀孕母羊的总钙和磷浓度。多项逻辑回归模型被拟合到数据以确定超声扫描结果的重要预测因子。单胎、双胎和三胎母羊的平均血清总 25(OH)D 浓度分别为 102.0 ± 3.4、101.0 ± 2.4 和 83.0 ± 4.5。在多项逻辑回归模型中，血清总 25(OH)D 和 25(OH)D3 浓度也与怀三胞胎的母羊呈负相关（P = 0.015），而体重与双胞胎和三胞胎的母羊显着相关（P怀三胞胎的绵羊血清 25(OH)D 浓度较低的原因尚不清楚，需要进一步研究以确定其背后的机制。