Cross breeding of Saudi Aradi with Damascus goats breeds for genetic improvement in the milk yield and composition

The aim of the present study was to evaluate the effects of crossing Saudi Aradi with Damascus goat breeds in improvement milk yield and composition. A total number of 366 healthy goats (150 Aradi goats, 157 Damascus goats and 59 their cross) was included in the study. Does were randomly divided into two groups and each group, Aradi does were subdivided into two subgroups; the first one was inseminated artificially from semen of bucks of the same breed and the second group was inseminated artificially from semen of Damascus breed bucks. Data were recorded for all animals during two seasons (S1, winter/Autumn, S2, spring/summer). Effects of the type of birth, breed, season, year and number of kids on milk yield (MY), fat% (F%) and protein% (P%) were statistically analyzed. The percentages of variation for milk yield and fat were moderate (38.93 % and 39.36%, respectively) but the differences between minimum and maximum were high ranged from 90.54 to 514.9 kg for milk yield and from 0.580 to 8.259% for fat%, while these variations for protein% were low (12.43%) but the difference between minimum and maximum were high ranged from 2.133 to 5.280%. The breed had a higher significant effect on milk yield and fat% (P≤ 0.01) and significant effect on protein% (P≤ 0.05). Crosses had higher protein% than Damascus and Aradi goats breeds. There was significant effect of the year on milk yield, fat% and protein% (highest level of milk yield, P≤ 0.05 and protein%, P≤ 0.01 recorded during 2006). Number of kids had highly significant effect (P≤ 0.01) on milk yield, protein and fat%. There were significant correlations among total milk yield, protein and fat% (P≤ 0.01). In conclusions, milk yield traits in Aradi goats were the lowest, so crossing with Damascus goats is the best program for upgrading and genetic improvement of milk yield in that breed.