Seasonal variations in physico-biochemical determinants of buffalo ( Bos bubalis) semen and their relation to fertility

Semen from eight Murrah buffalo bulls was collected and analysed for physical and biochemical determinants throughout the year. Depending upon the climatic conditions, the whole year was divided into four periods. The mean values of volume, density, mass motility and sperm concentration was 1·64 + 0·060 ml, 2·48±0·032 (3-point scale), 2·65±0·069 (5-point scale) and 1185 ±19·2 million/ml, respectively. The mean values of alkaline and acid phosphatases were 1238±47·4 and 1244±54·5 King-Armstrong units (KAU)/100 ml of seminal plasma. Average figures for citric acid, calcium, phosphorus, total nitrogen and non-protein nitrogen (NPN) were 507 + 14·1, 53·0±l·2, 121±4·9, 649±12·8 and 116±2·0 mg/100 ml of seminal plasma. Periods of the year had significant effect on volume, alkaline and acid phosphatases, citric acid and NPN ( P