العوامل المؤثرة في إنتاج الحليب المعدل على أساس 305 أيام عند بقر الهولشتاين فريزيان في مزرعة خرابو

الملخص EN

This study was conducted at Kharabo dairy station belongs to the Faculty of Agriculture، University of Damascus.

692 productive records for 269 Holstein Friesian cattle were used to study the effects of calving year, age at first calving، calving season and parity on the adjusted 305-day milk yield.

Data were exposed to GLM, analysis of variance was applied to determine the effect of studied factors and differences between averages were compared according to Duncan test using SPPS 17.

The overall mean for (305-d milk) was 6222.6 ± 62.01 kg.

and affected significantly (P < 0.001) by calving year and parity and (P<0.05) by age at first calving.

No significant effect for season was observed.

Results suggested that better management practices and improving the feeding status might help increasing the 305-d milk and making the status more economic efficient in the dairy cattle at Kharabo Farm.