Body condition score and season of calving effects on physiological parameters, productive and reproductive performance of Friesian cows

الملخص EN

Physical body condition of cows reared under tropical and subtropical conditions had an effect on productive and reproductive traits.

The reproduction efficiency is considered an important factor affecting the production and economic efficiency of dairy cows.

The present study was designed to investigate the effect of dam body condition score and season of calving on productive and reproductive performance of dairy cattle under hot condition.

Data were collected from thirty Friesian cows raised at the experimental Farm, College of Agriculture and Veterinary Medicine, Qassim University through 2013-2015 in summer and winter seasons.

The body condition score (BCS) was recorded on scale 1 to 5.

Cows were weighed at calving and body activity was determined.

Physiological parameters (Rectal temperature, Respiration rate and Pulse rate) were measured.

The traits studied represent total milk yield, daily milk yield, first estrus after calving, calving to conception interval (days open), number of services per conception, estrus rate, pregnancy rate.

Two way analysis of variance was used with BCS and season of calving as fixed effect.

The results showed that the physiological parameters increased in hot season.

The cows with BCS of 3 to 4 can decrease their physiological parameters.

Cows calved in hot season have lower weights, milk yield and body activity.

Cows with BCS of 3 showed the highest movement and the heaviest amount of milk yield.

Low reproductive performance was found for cows calved in summer season.

It could be concluded that Friesian cows in tropics and subtropics had an ability to survive and adjusted their body to withstand high ambient temperature.

Body condition score is considered an important factor to reflect ability of Friesian cows raised in hot environments.