Holstein cows performance under farming conditions at Chittagong region and fitting regression on their milk yield

Abstract

The study was undertaken to evaluate the productive and reproductive performance of Holstein crossbreds under three dairy farms in Chittagong district. Data were collected with a designed questionnaire on productive and reproductive traits. About 29 cows of 1st parity were taken as study population and cow’s age was ranges from 2 to 7 years and lactation number was from 1 to 5. It was found that with the increases of herd sizes milking cows number was also increases. Daily milk yield, lactation length and lactation milk production was varied with farms and lactation numbers. The daily milk yield and lactation milk yield was ranges from 16 to 23 litres and 1680 to 2360 litre, respectively. However the reproductive performance (calving interval and service per conception) did not vary with farms and lactations. Linear regression was fitted with the daily milk yield of Holstein crossbred cows of three farms and low fit was observed due to low R2 value.