Chronic Mastitis in Small Dairy Cattle Herds in Muang Khon Kaen

Monthly records of bulk tank milk somatic cell count (BMSCC) of all 194 dairy herds in Muang, Khon Kaen were used as an indicator of chronic mastitis problems; i.e. BMSCC > 500,000 cells/ml at least 3 consecutive records. Twelve chronic mastitis herds in Muang, Khon Kaen were data collected on 1) general herd information, 2) milking equipment, 3) milking procedure and 4) awareness and management of farmers to the mastitis problem. All possible mastitis pathogens were investigated in individual milk samples from 138 lactating cows of the herds. At least 40% of dairy herds in Muang, Khon Kaen had mastitis at each record and 23%(44 herds) had the long-term problem. Farmers of the 12 studied herds had poor managements on mastitis control, such as improper milking machine maintenance, no use of pre-dipping; foremilk had not been checked for abnormality, mastitis cows were milked with fresh cows. At the cow level, the prevalence of contagious bacteria, coagulase negative staphylococci (CNS) and opportunistic bacteria was 39%, 64% and 22%, respectively. Milking practice was identified as a risk factor of cow being infected intramammary by contagious bacteria and CNS.