This study was conducted at Kharabo Dairy Station belongs to the Faculty
of agriculture, University of Damascus. 553 records for 206 Holstein Friesian
cattle were used to study factors affecting the calving interval during 1982 to
2007. Data were
exposed eccording to GLM, and analysis of variance was used
to determine the calving interval (CI) and the effect of calving year, calving
season, parity and interactions on the calving interval, and Duncan test was
used to compare means by SPSS program. The overall mean for (CI) was
459.12±4.90 days. and affected significantly (0.001>P) by calving year, but
there was no significant effect for calving season, parity and interactions
between studied factors on the calving interval. These results suggested that
better management, and applaying more efficient administration practices as
well as to improving the feeding status may reduce calving interval to typical
period of 365 days and increase reproductive and economic efficiency of dairy
cattle at Kharabo station.
أدى استخدام عرق الهولشتاين فريزيان بشكل واسع في أعمال الخلط التربوي و الإنتاجي مع تحسين
العوامل البيئية إلى تحسين إنتاجية الأبقار من الحليب، إلا إنه قد سجل مع هذا التطور في إنتاج الحليـب
ازدياد في حالات أمراض التهاب الضرع Mastitis ، و قد أشارت المر
اجع العلمية في هذا السياق إلـى أن
الإصابة بأمراض التهاب الضرع يزداد احتماله مع ارتفاع إنتاجية الأبقـار مـن الحليـب، كمـا سـجلت اختلافات بين سلالات أو عروق الحليب بالنسبة لهذا المرض.