Reference ranges and seasonal variations in innate immune responses of kalbasu, Labeo calbasu (Hamilton)

Abstract

Kalbasu, Labeo calbasu (Hamilton) reared under natural conditions were examined for variation in some innate immune parameters during three different seasons of a year. The reference ranges for few innate immune parameters viz. lysozyme, peroxidase, ceruloplasmin, antiprotease and alternative complement haemolytic activities, superoxide production by phagocytes, total protein level of serum, haemolysin, haemagglutination and bacterial agglutination titres, and blood glucose level of this species were established. The seasonal and sex-related variations in some of the parameters in this fish were also evaluated. Significant seasonal variations in peroxidase activity, superoxide production by phagocytes, alternative complement activity and haemolysin titre were observed in kalbasu. In contrast, serum lysozyme activity and blood glucose level did not show significant seasonal variations. Males had only higher haemagglutination titre in the breeding season when compared to females.