Two surveys were carried out in peri-urban areas of Hochiminh City, in the South of Vietnam, in order to investigate the on-going situation of dairy production and to evaluate the prevalence of sub-clinical mastitis and its causal factors in smallholder dairy farms.
The first survey was conducted using a structured questionnaire interview and on farm observations on 120 dairy smallholder farms. The results show that dairy production is a new component in small household production, with an average herd size of 12 (ranging from 2 to 17 head). Most of the dairy farmers use intensive systems based on cut-and-carry of grasses, with by-products and commercial concentrates. The main breed (95.8%) was crossbred Holstein-Friesian (HF). Although the milk yield (15.98 kg/day) and milk quality were acceptable, the problems of high purchased feed, and poor reproduction performance were the main constraints in dairy production development in Hochiminh city.
The second survey was conducted to evaluate the prevalence of somatic cell count (SCC) and sub-clinical mastitis in smallholder dairy cows, with a total of 360 milk samples. The average SCC was 1,301,819 (SD=902,539; n=360) and 69% of the milking cows were considered to have sub-clinical mastitis. There was a trend of increased SCC with increasing crossbred generations, herd size, and number of parities. The SCC of the cows milked by hired labor was higher than in cows milked by family labor. The relationship between high milk SCC and milk yield on the test day was negatively correlated (χ2=19.31, DF=2, P=0.001).