Seasonal variation in serum enzyme activities of Nagavali sheep under tropical conditions

Abstract:

This study evaluated seasonal variation in serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) activities in Nagavali sheep maintained under tropical conditions. One hundred apparently healthy sheep (50 ewes and 50 rams), aged at least one year, were sampled during summer, monsoon, and winter. The temperature-humidity index (THI) was highest in summer (80.02 ± 0.43), followed by monsoon (70.51 ± 0.41) and winter (67.89 ± 0.27). Serum AST activity was significantly higher in summer than in monsoon and winter in both sexes and the total herd. ALT and ALP activities were also generally higher in summer and lower in winter. These findings indicate that seasonal thermal load is associated with measurable changes in serum enzyme activities in Nagavali sheep. The reported values may provide useful baseline information for clinical interpretation and management of this recently recognized breed under tropical production systems.