Abstract The aim of this study was to evaluate the history of a population of Saanen goats based on the population structure and the effect of inbreeding on accumulated 305-d milk yield (MY305) and lactation length (LL). Pedigree records of 7640 individuals born between 1997 and 2014 were analyzed and population parameters were estimated based on the probability of gene origin, effective population size (Ne), average inbreeding coefficient (F), flock classification according to origin and use of breeding animals, average relatedness coefficient (AR), pedigree completeness and number of generations using the ENDOG v4.8 program. A total of 79.57 %, 50.73 %, 29.10 % and 11.60 % of the examined individuals had pedigrees in the first, second, third and fourth ascendancy, respectively. The total number of founders and ancestors was 123 and 101, respectively, and 39 of the latter explained 50 % of the genetic variability in the population, which indicates a loss of original genes. The AR and F coefficients were 0.78 % and 1.48 %, respectively. There was no significant inbreeding effect on LL. The MY305 was significantly affected by inbreeding, with a reduction of 2.31 kg per 1% increase in the individual inbreeding coefficient. The LL and MY305 exhibited heritability of 0.03 and 0.18 respectively, with a genetic correlation of 0.97.

中文翻译：

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巴西生产系统中萨能山羊种群结构及近亲繁殖对产奶量的影响

摘要 本研究的目的是根据种群结构和近交对累计 305 天产奶量 (MY305) 和泌乳长度 (LL) 的影响来评估萨能山羊种群的历史。分析了 1997 年至 2014 年间出生的 7640 只个体的系谱记录，并根据基因起源概率、有效种群大小 (Ne)、平均近亲繁殖系数 (F)、根据繁殖动物的起源和用途进行种群分类，估计种群参数，使用 ENDOG v4.8 程序的平均相关系数 (AR)、谱系完整性和世代数。共有 79.57 %、50.73 %、29.10 % 和 11.60 % 的受检个体分别具有第一、第二、第三和第四优势的谱系。创始人和祖先的总数分别为 123 和 101，分别，后者的 39 解释了种群中 50% 的遗传变异，这表明原始基因的丢失。AR 和 F 系数分别为 0.78% 和 1.48%。对 LL 没有显着的近亲繁殖影响。MY305 受近交影响显着，个体近交系数每增加 1% 减少 2.31 kg。LL 和 MY305 的遗传力分别为 0.03 和 0.18，遗传相关性为 0.97。个体近交系数每增加 1% 增加 31 公斤。LL 和 MY305 的遗传力分别为 0.03 和 0.18，遗传相关性为 0.97。个体近交系数每增加 1% 增加 31 公斤。LL 和 MY305 的遗传力分别为 0.03 和 0.18，遗传相关性为 0.97。