Vol. 10, Special Issue 8 (2025)

A study was conducted to examine the mechanism of the effects of clinical mastitis on the milk yield of dairy cows. Local farmers in Tamil Nadu's western districts provided milk samples. Milk yield was measured for each animal every 10 days before and after mastitis. A total of 54 mastitis-affected cows were selected. 18 milch cows were examined at different stages during early, mid, and late lactation. Six milch cows from each bred viz., Kangayam, crossbred Holstein Friesian cows, crossbred Jersey cows were selected in each stage during early lactation, mid lactation and late lactation.
Mean of highest yield of raw milk produced per day for Kangayam tract was recorded in early lactation period (1.68±0.01 L/d) and the lowest yield of raw milk produced per day for Kangayam tract was recorded in late lactation period 10 days after mastitis infection as (1.00±0.04 L/d)). Mean of highest yield of raw milk produced per day for Holstein crossbred milch cows was recorded in early lactation period (12.22±0.12 L/d)) and the lowest yield of raw milk produced per day after 10 days of mastitis affected Holstein crossbred milch cows was recorded in late lactation period (6.71±0.02 L/d)). Mean of highest yield of raw milk produced per day for Jersey crossbred milch cows was recorded in early lactation period (8.95±0.11 L/d)) and the lowest yield of raw milk produced per day after 10 days of mastitis affected Jersey crossbred was recorded in late lactation period (5.71±0.03 L/d)). The yield of raw milk produced per day of Kangayam cows, of Holstein crossbred cows, Jersey crossbred cows in early, mid and late lactation period before mastitis and 10 days after mastitis infection differed significantly (p?0.05).