Discipline: Veterinary Medicine
Individual quarters of dairy cows from backyard farms in Laguna and Batangas were subjected to California mastitis test (CMT) to detect subclinical mastitis in individual cows and quarters. Teats identified as positive for mastitis were further evaluated for microbial carriage through bacterial isolation and identification using conventional methods and BBL Crystal ID®. A total of 97 cows from Batangas and Laguna were tested, of which 46 cows (49.5%) had at least one teat having a CMT score of trace, 1, 2 or 3. From 88 CMT-positive teats, a total of 132 organisms were recovered. The most common isolate in both Laguna and Batangas was Staphylococcus aureus (41 or 31% of isolates). Other common isolates in both provinces included Escherichia coli (12.9%), Pseudomonas stutzeri (10.6%), Bacillus cereus (7.6%), and Staphylococcus hemolyticus (6.8%). Less frequently recovered bacteria in either province were Aerococcus viridians (4%), Klebsiella pneumoniae (4%), Staphylococcus warneri (4%), Lactococcus lactis ssp cremoris (3%), Streptococcus agalactiae (3%), Staphylococcus albus (3%), Aerococcus urinae (1.5%), Staphylococcus capitis (1.5.%), Streptococcus spp. (1.5%), Acinetobacter iwoffi (0.5%), Corynebacterium striatum (0.5%), Micrococcus kristinae (0.5%), Micrococcus luteum (0.5%), Micrococcus sp. (0.5%), Pseudomonas aeruginosa (0.5%), Shigella sp. (0.5%), and Streptococcus pyogenes (0.5%). This study established that subclinical mastitis remains to be a common problem in backyard dairy farms in Laguna and Batangas and that Staphylococcus aureus appears to be the most predominant bacteria in such cases from both provinces.