Economic impact of subclinical mastitis in Bangladeshi crossbred dairy cattle

This study quantified the economic losses associated with subclinical mastitis in crossbred dairy cattle in Sirajganj, Bangladesh. Between January 2023 and December 2024, a total of 3,174 lactating cows from 76 herds were sampled. Composite milk samples (40 mL) were aseptically collected, transported to the laboratory within one hour, and analyzed for SCC using the EKOMILK SCAN® analyzer. Cow-level data—including age, breed, parity, lactation stage, pregnancy status, milk yield, and history of clinical mastitis—were obtained through a pre-tested questionnaire. Milk yield loss associated with elevated SCC was estimated using multivariable mixed-effects linear regression, accounting for herd-level clustering. SCC values were centered at 200,000 cells/mL, and coefficients were rescaled to reflect yield loss per 100,000-cell/mL increase above this threshold. Estimated losses were calculated with 95% confidence intervals, aggregated to herd-level, and standardized to a 1,000-cow basis. Economic impacts were derived by multiplying milk losses by the prevailing milk price (BDT 60/L) and expressed in Bangladeshi Taka (BDT) and U.S. dollars (USD 1 = BDT 122). During the ‘bathan’ period, average loss was 0.10 L/cow/day (BDT 6.03), equivalent to 100.5 L/day for 1,000 cows (BDT 6,028.90; USD 49.42). In the ‘non-bathan’ period, losses doubled to 0.20 L/cow/day (BDT 11.98), or 200 L/day per 1,000 cows (BDT 11,976.2; USD 98.17). SCC showed a consistent negative association with yield, with higher losses observed during confinement. Herd-level variation suggested strong management influences. Improving cow comfort and ensuring access to green grass or silage throughout the year can decrease SCC-related losses and increase farm profitability.