摘要
The present investigation aimed to evaluate the population structure and inbreeding of Holstein herds in southern Brazil. To carry out the analysis, the Associação Paranaense de Criadores de Bovinos da Raça Holandesa (APCBRH) in Brazil provided the data, which consisted of a pedigree file of 206,796 animals born between 1970 and 2014. Results regarding the following parameters were determined: pedigree integrity, effective number of founders, effective number of ancestors, generation interval, inbreeding coefficient, realized effective population size, and average relatedness coefficient. POPREP and ENDOG v.4.5 software packages were employed to estimate these parameters. Based on the data set, the mean generation interval was found to be 6.3 years, and the average inbreeding coefficient, related to inbred animals, was 4.99%. Furthermore, the realized effective population size varied throughout the time period, ranging from 22 to 114, whereas the rate of inbreeding in this same period showed a decreasing trend towards the later years in the period until 2014. Upon evaluation, average relatedness coefficient was estimated to be 0.71%. Moreover, the effective number of founders and ancestors were estimated as 418 and 400 animals, respectively. According to the level of inbreeding observed, it could be noticed that genetic diversity remains elevated, which will be important to the genetic progress in the Holstein breeding program in Southern Brazil.
摘要译文
本次调查旨在评估巴西南部荷斯坦牛群的种群结构和近亲繁殖。为了进行分析，巴西的波索诺斯达拉索·霍兰德萨分会（APCBRH）提供了数据，其中包括1970年至2014年之间出生的206,796头动物的家谱档案。确定了以下参数的结果：谱系完整性，有效的创建者数量，有效的祖先数量，世代间隔，近交系数，已实现的有效种群数量和平均相关系数。使用POPREP和ENDOG v.4.5软件包来估计这些参数。根据数据集，发现平均繁殖间隔为6.3年，与近交动物有关的平均近交系数为4.99％。此外，实际有效人口数量在整个时间段内变化，范围从22到114，而在同一时期内的近亲繁殖率在直到2014年的后期呈现出下降趋势。根据评估，估计了平均相关系数为0.71％。此外，创始人和祖先的有效数量分别估计为418只和400只。根据观察到的近交程度，可以注意到遗传多样性仍然很高，这对于巴西南部荷斯坦育种计划的遗传进展至关重要。
SIEKLICKI; Michelli de Fátima et al.. Population structure and inbreeding of Holstein cattle in southern Brazil.[J]. Revista Brasileira de Zootecnia, 2020,49(49)