Season influence on citric acid and fructose concentration in ram semen

Abstract

Citric acid and fructose concentrations were studied from March 1996 to March 1997, using 24 rams, of three to four years of age. Nine of them were from the breeds Bergamácia (Be), eight Corriedale (Co) and seven Hampshire Down (Hd). The semen was collected each 30 days, as well as climatic conditions data: wind speed (v), air temperature (Ta), globe temperature (Tg) and relative humidity (Ur). The citric acid concentração showed a quadratic behavior (P < 0.05), being higher in summer (January - 3.16 and 5.24mg/ml) and smaller in spring (September - 0.23 and 2.31mg/ml), respectively for Be and Hd breeds. There was no effect (P > 0.05) of the season on citric acid concentration for Co breed. The Be breed had a linear behaviour (P < 0.05) for frutosis, being higher in summer (January - 4.70mg/ml), decreasing in fall (May - 3.08mg/ml) and spring (November - 0.65mg/ml). There was no seasonal effect (P > 0,05) on frutosis concentration for the Co and Hd breeds. Corriedale breed suffered smaller effect on the concentration cf citric acid and frutose, indicating better acclimatization the environmental conditions.