Evaluation of Awassi sheep genotypes for growth, milk production and milk composition

Abstract

We evaluated growth, milk production and composition of Awassi genotypes based on 9 years data collected from the International Center for Agricultural Research in the Dry Areas (ICARDA) flock kept in Tal Hadya station, Syria (now moved to Terbol station, Lebanon). Performances of the pure genotypes (Syrian and Turkish Awassi) and the resulting crosses were compared. Growth performances did not differ among the genetic groups except for weaning weight, for which the Turkish Awassi was lighter than the Syrian Awassi and all its crosses; the 75% Syrian genotype being the heaviest (19.54±0.43 kg). Genetic groups did not differ (p>0.05) for both lactation length (overall mean 100.39±1.20 days) and lactation milk yield (overall mean 91.2±2.50 kg). Lactation yields of milk constituents (fat, protein, lactose, total solids and solids-not-fat) were, however, higher for the 75% Syrian crosses compared to the other crosses as well as to the pure Awassi sheep, except for lactation protein yield. The performances of Turkish Awassi were not superior to those of the Syrian genotype for all the traits considered under the environmental conditions of Syria. It is concluded that the Turkish Awassi should not be used as an improver breed for the Syrian genotype. The performance of the ICARDA maintained Awassi flock has on average been better compared to those of other farms in the region. Improved rams produced from the breeding program could therefore serve as improver for flocks maintained in countries of the region, necessitating the development of appropriate delivery systems of improved genetics.

Udder Measurements and Their Relationship with Milk Yield in Pelibuey Ewes

“…Our analysis was highly accurate (Cb > 0.852 and RMSEP > 29%) in predicting milk yield according to the selected udder measurements, but the precision (r 2 < 0.632) was systematically low, resulting in under prediction (CD < 1.897) across equations. The variation in milk yield may be largely explained by environmental effects [6] or genotype [6,15,37]. Although the previous studies indicated that ewes rearing twin lambs had higher daily milk yields [6,38], because of low prolificacy in the present study (1.13), the effect of litter size could not be determined due to insufficient statistical power.…”

Milk Production Abilities of Kıvırcık Ewes

“…Mean values of lactation milk yield and lactation length obtained in this study were higher than the values reported in other studies on Kıvırcık sheep (Sönmez, 1987;Kaymakçı and Sönmez, 1996;Karaca et al, 1999;Altınel et al, 2000;Yilmaz and Altın, 2004;Ceyhan et al, 2007). Similarly, values for these parameters were higher than values reported for Syrian Awassi, Turkish Awassi and crossbred sheep between Syrian and Turkish Awassi (Haile et al, 2017). On the other hand, lactation milk yield was lower than values in Ghezel and Mehraban sheep breeds raised in Iran that reported by Izadifard and Zamiri (1997).…”

Effect of Breed and Some Non - Genetic Factors on Milk Production and Some Proportions of Its Chemical Components in Two Breeds of Local Sheep

“…Milk production is a quantitative characteristic that is influenced by many factors, including genetic animals, non-genetic factors such as age, sex, health status, etc. [2]. it was observed that the breed effect was highly significant in the daily and total milk production in a study conducted by [3] .…”