Influence of the Time of Year on the Reproductive Efficiency of Dazu Black and Mongolian White Cashm

With the aim to evaluate the reproductive performance of the Dazu Black (DZB) and Mongolian White Cashmere (IMCG) goats' races according to the times of the year. To integrate these reproductive traits, they were compared at different times of the year. At the same time, the prolific, fertility and fertility of herds were evaluated. Significant differences between epochs (P< 0.01) were determined for the fertility variable, although the fertility rate of DZB goats was higher (85.2%) compared to IMCG (79.7%), no significant differences were observed. The variable prolificity shows high values in the four measures, and no statistically significant differences were found for them. As for the number of births per epoch, the highest values were found in the spring for the DZB breed and summer for IMCG. Correlations showed average results with positive correlations of 56.60% for DZB and 62.26% for IMCG. The time of year influenced the number of offspring at birth negatively (r-0.06), the highest number of births occurred in spring for DZB and in summer for MWC and the presence of double births prevailed in both races during the period evaluated. The Dazu Black and Mongolian White Cashmere goats have defined characteristics that have modeled the genetic and phenotypic structure as a standard for each breed through environmental influence and cultural practices. This aspect demonstrates the adaptation and rusticity of goats and their ability to consume and take advantage of available foods. The sample size, distribution and methodology used in this research makes it possible to conclude that DZB goats and IMCG are a valuable genetic resource for adaptation, rusticity and productive efficiency.