Study of the relationship between the production of milk and some of its components with the growth of lambs in two breeds of Iraqi sheep

Abstract

A total of 1116 records Awassi ewes and 432 of Hamdania ewes were collected and which belong animals resource department, Faculty of Agriculture and Forestry at the University of Mosul for the years 2008, 2009 and 2010 to study the effect of genetic and non-genetic factors in milk production and some of its components from birth until weaning. The results showed significant effects (p≤0.05) for the breed and highly significant effects (p≤ 0.001) for the year, mother's age, sex, and type of birth in the daily milk production. There was a highly significant effect of year in milk fat, protein, and lactose. same there was a significant effect for age at weaning on birth weight, and highly significant effects for the breed, year, age of dam, sex, type of birth, and age at weaning on birth, weaning and weight gain from birth to weaning. The highest value for repeatability was 0.398, 0.309 in Awassi ewes for weight gain and in Hamdani ewes for daily milk yield respectively. Phenotypic and genetic correlation between protein and lactose in Awassi ewes 0.507 and 0.410, and in Hamdani ewes 0.641 and 0.157 respectively were highly significant.