A survey on seasonal changes of serum testosterone concentration in male cats of Ahvaz region

Environmental temperature and photoperiod are among the important factors that may influence the reproductive cycle of various species. The aim of the present survey was to evaluate the different seasonal influences (cold= January and warm= July) and their intermediate seasons (April and October) on serum testosterone concentration in cats of Ahvaz region. For this purpose, one hundred and twenty adult male cats (domestic short hair breed) were examined. Blood samples were taken of thirty cats in each season, and testosterone concentration was measured using ELISA technique in serum samples. The average testosterone concentration of 3.42±0.49 ng/ml was detected in the studied cats. The minimum and maximum of serum testosterone level was also 0.01 and 17.2 ng/ml, in July and January respectively. The minimum of mean testosterone concentration was obtained in the warm season (0.62±0.23 ng/ml), while the maximum mean level was detected in the cold season (9.87±1.28 ng/ml). The mean testosterone concentration in spring and autumn was 2.26±0.5 and 0.94±0.3 ng/ml respectively. Environmental temperature and photoperiod correlated negatively with the testosterone concentration. The correlation coefficient between testosterone concentration with the average of minimum, maximum and total temperature, was calculated as R= -0.572, R= -0.615 and     R= -0.597 respectively. The correlation coefficient indicated an acceptable and high correlation of the negative (inverse) type, between testosterone concentration and photoperiod (R= -0.256). In conclusion, testosterone concentration is under the influence of season, with the mean testosterone concentration significantly lower in summer than the other seasons (p<0.05).