Mahmoud  Al-Mohamed ^(1)*

(1). Department of  Animal Production, Faculty of Agricultural Engineering, University of Aleppo, Aleppo, Syria.

(*Corresponding author: Dr. Mahmoud Al-Mohamed. E-Mail: Mahmoud.lb.Almohamed@gmail.com).

Received  1/06 /2024                 Accepted: 1 /08 /2024

Abstract: 

This study aimed to evaluate the effect of the Dry Period Length on some reproductive performance indicators for the subsequent lactation. It was conducted on 74 Holstein Friesian cows, belonging to the herd of the Jeb Ramla cattle station, in Syria, during 2022-2024. The cows were classified according to the Dry Period Length into (less than 45, 46-55, more than 56 days), and the effect of the length of the dry period was studied on the Services per conception, days open, Calving interval, Length of pregnancy, weight Calf at birth, Estrus rate. The data was analyzed using SPSS26 software. The results showed a highly significant effect of the Dry Period Length on all indicators studied, except for the effect on the Estrus rate, as the effect non-significance. The results showed that shortening the Dry Period Length to weak fertility, and long Dry Period Length to an increase in the values of reproductive indicators. The best reproductive indicators were with a dry period of 46-55 days.

Key words: Dry Period Length, reproductive performance, Holstein cows.

Full paper in Arabic: pdf