Wesam Al-Saife(1) , Soliman Salhab(2)& Khaled El-Najjar(1)
(1). Animal Wealth Research Administration, General Commission for Scientific Agricultural Research, P. O. Box 113,Doma, Damascus, Syria.
(2). Department of Animal production, Faculty of Agriculture, Damascus University. Damascus, Syria.
(Corresponding author: Eng. Wesam Al-Saife: Animal Wealth Research Administration, General Commission for Scientific Agricultural Research, P. O. Box 113, Doma, Damascus, Syria. E-mail: bombix668@hotmail.com).
Received: 22 / 07 / 2014 Accepted: 20 / 12 / 2014
Abstract:
This research was conducted in 2010, to determine the age at first calving (AFC) in Shami cattle reared in Dier Alhajar Research Station of the General Commission for Scientific Agricultural Research (GCSAR), and determine the effect of sire, birth year, birth season and their interactions. 738 records of Shami cattle were collected between 1981 and 2006 and used. Data were subjected to general linear model and the analysis of variance was used to determine the effect of sire, birth year, birth season, and their interactions. Least Square Means (LSM) and Standard Error (SE) were used for calculation of (AFC). Duncan test was used to compare means. SAS –program (1996) was used for the statistical analysis. Results indicated that, Least Square Means and Standard Error for (AFC) ranged between 27.80 and 37.77 month, with general mean 32.49±5.15 month. Effect of birth year was significant (P<0.01), while the effects of sire and another factors were not significant. It was concluded that AFC can be reduced by better management and by providing good and suitable rearing and feeding conditions –
Key words: Age at first calving, Shami cattle, Genetic and non genetic factors.
Full paper in Arabic:
تأثير كل من الأب وسنة وفصل الميلاد في العمر عند الولادة الأولى عند الأبقار الشامية في سورية