Abstract

 

Buffaloes play an imperative role in the Indian economy as nearly 56% of the total national milk production is catered by them and graded Murrah buffaloes are prevalent throughout the country owing to their nonpareil milk production potential coupled with advantageous acclimatization aptitude and feed conversion proficiency. Lactation being a high profile production phase, these animals have to adjust their biology to cater to milk production and since numerous hormones play a role in the lactational process our study was conceptualised to profile key hormones and correlate them with THI (Temperature Humidity Index) during one complete lactation (parturition to dry period) in the selected Murrah buffaloes (n = 15) who were in their 2nd – 4th lactation, housed on the same farm in the Thane district of Maharashtra state in India. Blood samples were collected on 7th and 15th day of parturition and fortnightly thereafter until drying off (210 lactation days) and farm THI was recorded on the collection days. The results showed significant (p<0.01) variations in growth hormone, IGF1, T3, T4, cortisol and insulin concentrations but were non-significant for leptin. Insulin significantly and positively correlated to THI and IGF1 significantly negatively correlated with THI. The remaining analysed hormones did not show any significant correlation. Further, growth hormone and cortisol negatively correlated with THI, whereas T3 and T4 positively correlated with THI. This non-significant result could possibly be due to the fact that the lactation period was from July to February, and consequently the buffaloes escaped the summer heat stress.

Keywords

Murrah buffaloes; Hormones; T3 and T4