Resumen

VALERO-LEAL, Kutchynskaya et al. Contagious and Environmental Pathogens Isolated from Mammary Quarters With Subclinical Mastitis of Risk High in Three Farms of Zulia State. Rev. cient. (Maracaibo) [online]. 2010, vol.20, n.5, pp.498-505. ISSN 0798-2259.

Mastitis is the commonest and most expensive disease in dairy cattle in most countries. In the present study it was investigated the frequency of isolates of contagious and environmental pathogens of subclinical mastitis on three farms of Zulia State. Was determined association by groups of pathogens with different milking systems used in each farm and the likely effect of the seasons. At the field level, California Mastitis Test (CMT) was performed to 2,416 mammary quarters. A 758 quarters that were classified as risks high by the CMT, also were cultured bacteriologically. In general, the most frequently isolated bacteria were S. agalactiae (26%), coagulase-negative Staphylococcus (23%), Streptococcus spp. (20%) and S. aureus (17%). Seventy three percent of isolated pathogens were contagious. The contagious nature of intramammary infection was observed in the three farms with a frequency of 75, 86 and 68% in farms A, B and C, respectively. The results did not allow inferring a clear seasonal pattern for the presence of contagious and environmental pathogens.

Palabras clave : Subclinical mastitis; contagious pathogens; environmental pathogens.