Estimating variance components and breeding values for number of oocytes and number of embryos in dairy cattle using a single-step genomic evaluation

Reproductive technologies such as multiple ovulation and embryo transfer (MOET) and ovum pick-up (OPU) accelerate genetic improvement in dairy breeding schemes. To enhance the efficiency of embryo production, breeding values for traits such as number of oocytes (NoO) and number of MOET embryos (NoM) can help in selection of donors with high MOET or OPU efficiency. The aim of this study was therefore to estimate variance components and (genomic) breeding values for NoO and NoM based on Dutch Holstein data. Furthermore, a 10-fold cross-validation was carried out to assess the accuracy of pedigree and genomic breeding values for NoO and NoM. For NoO, 40,734 OPU sessions between 1993 and 2015 were analyzed. These OPU sessions originated from 2,543 donors, from which 1,144 were genotyped. For NoM, 35,695 sessions between 1994 and 2015 were analyzed. These MOET sessions originated from 13,868 donors, from which 3,716 were genotyped. Analyses were done using only pedigree information and using a single-step genomic BLUP (ssGBLUP) approach combining genomic information and pedigree information. Heritabilities were very similar based on pedigree information or based on ssGBLUP [i.e., 0.32 (standard error = 0.03) for NoO and 0.21 (standard error = 0.01) for NoM with pedigree, 0.31 (standard error = 0.03) for NoO, and 0.22 (standard error = 0.01) for NoM with ssGBLUP]. For animals without their own information as mimicked in the cross-validation, the accuracy of pedigree-based breeding values was 0.46 for NoO and NoM. The accuracies of genomic breeding values from ssGBLUP were 0.54 for NoO and 0.52 for NoM. These results show that including genomic information increases the accuracies. These moderate accuracies in combination with a large genetic variance show good opportunities for selection of potential bull dams.     

高压液相色谱法测定林蛙油、中华绒螯蟹卵和 鲫鱼卵中雌二醇的含量

目的 利用高压液相色谱法测定东北林蛙输卵管(林蛙油)、中华绒螯蟹卵(蟹黄)以及鲫鱼卵(籽)中雌二醇的含量。方法 色谱柱为Agilent Zorbax SB-C18柱(4.6 mm×250 mm, 5 μm), 流动相为乙腈-水(63:37), 检测波长280 nm, 流速1.0 mL/min, 柱温30 ℃, 进样量为10 μL。结果 在0.3?10 μg/mL浓度范围内, 高压液相色谱图峰面积与雌二醇浓度线性关系良好, 其回归方程为Y=4203.8X-661.95, 相关系数R=0.9991。林蛙油、中华绒螯蟹卵和鲫鱼卵中雌二醇的含量分别为3.00、0.42、0.54 μg/g。结论 超声波法可以有效提取样品中的雌二醇, 通过优化所建立的方法对其具有良好的线性关系和回收率, 高压液相色谱峰型美观、分离效果好。     

海参花成分分析及对小鼠认知辨别能力的影响

本研究主要对海参花进行了成分分析并研究了其对小鼠认知辨别能力的影响.70只SPF级雄性ICR小鼠按体重随机分为空白组、东茛菪碱模型组、吡拉西坦阳性组(400 mg/kg),海参花低、中、高剂量组(75、150、450 mg/kg).每天灌胃给药30 min后腹腔注射1 mg/kg东莨菪碱造模.30 d后进行旷场实验、新...