title: Incidence of subclinical mastitis and prevalence of major mastitis pathogens in organized farms and unorganized sectors.
abstract: Subclinical mastitis (SCM) represents a major proportion of the burden of mastitis. Determining somatic cell count (SCC) and electrical conductivity (EC) of milk are useful approaches to detect SCM. In order to correlate grades of SCM with the load of five major mastitis pathogens, 246 milk samples from a handful of organized and unorganized sectors were screened. SCC (>5 × 10(5)/mL) and EC (>6.5 mS/cm) identified 110 (45 %) and 153 (62 %) samples, respectively, to be from SCM cases. Randomly selected SCM-negative samples as well as 186 samples positive by either SCC or EC were then evaluated for isolation of five major mastitis-associated bacteria. Of the 323 isolates obtained, 95 each were S. aureus and coagulase-negative staphylococci (CoNS), 48 were E. coli and 85 were streptococci. There was no association between the distribution of organisms and (a) the different groups of SCC, or (b) organised farms and unorganised sectors. By contrast, there was a significant difference in the distribution of CoNS, and not other species, between organized farms and unorganized sectors. In summary, bacteria were isolated irrespective of the density of somatic cells or the type of farm setting, and the frequency of isolation of CoNS was higher with organized farms. These results suggest the requirement for fine tuning SCC and EC limits and the higher probability for CoNS to be associated with SCM in organized diary sectors, and have implications for the identification, management and control of mastitis in India.
authors.affiliation: Veterinary College, Karnataka Veterinary, Animal and Fisheries Sciences University, Hebbal, 560024 Bengaluru India ; Institute of Animal Health & Veterinary Biologicals, Hebbal, 560024 Bengaluru India.
authors.forename: Raveendra
authors.initials: R
authors.lastname: Hegde
authors.affiliation: Veterinary College, Karnataka Veterinary, Animal and Fisheries Sciences University, Hebbal, 560024 Bengaluru India.
authors.forename: Shrikrishna
authors.initials: S
authors.lastname: Isloor
authors.affiliation: Veterinary College, Karnataka Veterinary, Animal and Fisheries Sciences University, Hebbal, 560024 Bengaluru India.
authors.forename: K Nithin
authors.initials: KN
authors.lastname: Prabhu
authors.affiliation: Project Directorate on Animal Disease Monitoring and Surveillance, Hebbal, 560024 Bengaluru India.
authors.forename: B R
authors.initials: BR
authors.lastname: Shome
authors.affiliation: Veterinary College, Karnataka Veterinary, Animal and Fisheries Sciences University, Hebbal, 560024 Bengaluru India.
authors.forename: D
authors.initials: D
authors.lastname: Rathnamma
authors.affiliation: Indian Veterinary Research Institute, Hebbal, 560024 Bengaluru India.
authors.forename: V V S
authors.initials: VV
authors.lastname: Suryanarayana
authors.affiliation: Veterinary College, Karnataka Veterinary, Animal and Fisheries Sciences University, Hebbal, 560024 Bengaluru India.
authors.forename: S
authors.initials: S
authors.lastname: Yatiraj
authors.affiliation: Institute of Animal Health & Veterinary Biologicals, Hebbal, 560024 Bengaluru India.
authors.forename: C Renuka
authors.initials: CR
authors.lastname: Prasad
authors.affiliation: Veterinary College, Karnataka Veterinary, Animal and Fisheries Sciences University, Hebbal, 560024 Bengaluru India.
authors.forename: N
authors.initials: N
authors.lastname: Krishnaveni
authors.affiliation: Veterinary College, Karnataka Veterinary, Animal and Fisheries Sciences University, Hebbal, 560024 Bengaluru India.
authors.forename: S
authors.initials: S
authors.lastname: Sundareshan
authors.affiliation: Veterinary College, Karnataka Veterinary, Animal and Fisheries Sciences University, Hebbal, 560024 Bengaluru India.
authors.forename: D S
authors.initials: DS
authors.lastname: Akhila
authors.affiliation: Institute of Animal Health & Veterinary Biologicals, Hebbal, 560024 Bengaluru India.
authors.forename: A R
authors.initials: AR
authors.lastname: Gomes
authors.affiliation: Ella Foundation, Genome Valley, Turkapally, Shameerpet Mandal, Hyderabad, 500078 Andhra Pradesh India.
authors.forename: Nagendra R
authors.initials: NR
authors.lastname: Hegde
keywords: Electrical conductivity; Major bacterial pathogens causing mastitis; Somatic cell count; Subclinical mastitis