Genetic Evaluation of Some Productive Traits in Maraz Goats

Abstract

This study was carriedout at the private project of Maraz goats at Bamerny sub-district/Amadiya district /Duhok governorate/Kurdistan Region of Iraq, and consists of 71 does, 8 bucks, as well as 234, 171 and 162 kids at birth, weaning and six month of age, respectively during two kidding seasons (2015-2016) and (2016- 2017). Milk traits consist of 121 records of each daily (DMY), total (TMY), pre-weaning (PRMY), peak milk yield (PKMY) and time to peak (TPMY), and 120 records of post weaning milk yield (POMY). Animal Model Program for single trait was used to predict the breeding value (PBV) and the real producing ability (RPA) for animals depending on one trait and then these values were ranked in descending order for each sex for selection. Rank correlation was calculated between estimates for both kid body weights and milk yield traits. The average breeding values for sires, dams, male kids and female kids were 0.1322, 0.0845, 0.0369 and 0.0247 kg for birth weight and 0.9877, 0.6804, 2.0072 and -0.6406 kg for weaning weight and 1.4295, 2.0184, 3.0952 and -1.0623 kg for six-month weight, respectively. Rank correlation coefficient (P≤0.001) between the breeding value estimates of birth weight and each of weaning weight and six-month weight were 0.36 and 0.28, respectively and between weaning weight and six-month weight was 0.84. Also the average RPA of 71 dams was estimated depending on their kid body weights at birth, weaning and six-months old were 0.0784, 3.7027 and 4.9492 kg, respectively. Also rank correlations coefficient were estimated between real producing ability of birth weight and each of weaning weight and six-month weight were 0.37 and 0.26, respectively and between weaning weight and SMWT was 0.81. In addition, the average producing ability were estimated for 71 Maraz does depending on their (DMY), (TMY), (PRMY), (PRMY), (PKMY) and (TPMY) were 0.0312, - 7.0378, -3.6234, -2.4199, 0.0477 and 0.2724 kg, respectively. Also rank correlations between real producing ability of all milk traits have been estimated and it was significant except between TPMY and each DMY, PRMY and PKMY, the significant correlation between RPA of milk traits assist to select the best animals and improve the herd genetically.