Vyas Jayesh, Kumar Ishmeet, Chitra Anil, Mukherjee Sabyasachi, Ganguly Indrajit, Mukherjee Anupama
Quantitative Genetics and Genomics Lab, Animal Genetics and Breeding Division, ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India.
Division of Animal Genetics, ICAR-National Bureau of Animal Genetic Resources, Karnal, Haryana, 132001, India.
Trop Anim Health Prod. 2025 Jul 24;57(7):318. doi: 10.1007/s11250-025-04564-8.
The present study conducted on an organised herd of Sahiwal cattle to elucidate the population structure parameter based on seven decades of genealogical information. The genealogical data (N = 4164) spanning 1949 to 2023 maintained at ICAR-National Dairy Research Institute, Karnal, India was considered with the aim to evaluate depth and accuracy of pedigree, population parameter and genetic diversity in different breeding schemes for whole population and pertinent reference cohort. The animal born from 1979 to 2009 grouped as reference 1 and from 2010 to 2023 as reference 2 cohort. The comprehensiveness of the whole population, reference 1 and reference 2 was over 50% up to the fourth, third and sixth generations respectively. The average relatedness and inbreeding coefficient were 5.92% and 2.69% for whole population, 5.44% and 1.96% for reference 1 and 6.98% and 3.85% for reference 2 respectively. The effective population size varied from 32.31 to 145.51 in the study. The average generation interval varies from 9.2 years in reference 1 to 8.2 years in whole pedigree and 6.6 years in reference 2 under study. The ratio (f/f) of effective number of founders (f) and ancestors (f) were 1.67, 1.59 and 1.90 for the whole, reference 1 and reference 2 respectively. The estimate for f/f ratio indicated that 54% of ancestral genetic diversity is retained in the current generation. Thus, present study provides critical insights to maintain effective population size, rate and level of inbreeding with contribution of founders in current population for optimum genetic diversity and improving breeding efficiency in planning future breeding programs.
本研究以一群有组织的萨希瓦尔牛为对象，基于七十年的系谱信息阐明种群结构参数。考虑了印度卡纳尔的印度农业研究理事会国家乳品研究所保存的1949年至2023年的系谱数据（N = 4164），目的是评估整个种群和相关参考队列在不同育种方案中的系谱深度和准确性、种群参数及遗传多样性。1979年至2009年出生的动物归为参考1队列，2010年至2023年出生的动物归为参考2队列。整个种群、参考1队列和参考2队列的完整性分别在第四代、第三代和第六代时超过50%。整个种群的平均亲缘系数和近交系数分别为5.92%和2.69%，参考1队列分别为5.44%和1.96%，参考2队列分别为6.98%和3.85%。研究中的有效种群大小在32.31至145.51之间变化。研究中参考1队列的平均世代间隔为9.2年，整个系谱为8.2年，参考2队列为6.6年。整个种群、参考1队列和参考2队列的有效奠基者数（f）与祖先数（f）的比率（f/f）分别为1.67、1.59和1.90。f/f比率的估计表明，当前世代保留了54%的祖先遗传多样性。因此，本研究为维持有效种群大小、近交速率和水平提供了关键见解，同时明确了奠基者对当前种群的贡献，以实现最佳遗传多样性并提高未来育种计划规划中的育种效率。
