Genotype x environment interaction on fertility traits of crossbred dairy cows under tropical climatic conditions of India

Abstract

Present study was envisaged to examine existence of genetic group x THI in crossbred cows at institute herd of ERS, ICAR-NDRI, Kalyani, West Bengal. 1041 fertility records each on service period (SP) and conception rate (CR) and weather parameters spanned over 22 years (1994-2015) were collected; arranged under three THI groups; thermal comfort (THI78 and six genetic groups.SP was longest (163.61 ± 6.83 days) when THI>78and lowest (149.27±6.69 days) during THI78 and highest (70.54±2.8 %) at THI78.Cows bearing 50% Jersey and 50% indigenous cattle inheritance followed by 50% Jersey + 50% Red Sindhi and 50% Jersey + 50% Tharparkar depicted least drop in CR at THI>78 (-2.38, -2.40 and -3.6%) in comparison to THI75% Jersey depicted maximum increase in SP (15.33 days) and drop in CR (-7.43%) at THI>78.

Keywords

• THI
• Genotype x environment
• Heat stress
• Crossbred cows