Background and Aim: Brucellosis is a zoonotic disease of high economic and public health importance in large and small ruminant populations worldwide. A cross-sectional study was conducted to determine the seroprevalence and risk factors of brucellosis in small ruminants in organized farms in the southern region of India. Materials and Methods: Farms exclusively rearing sheep and goats were selected based on the number of animals (small, medium, or large) and the location of the farm (urban, periurban, or rural). A total of 1499 serum samples; 1001 from sheeps and 498 from goats were sourced from six sheep and four goat farms and tested using Rose Bengal Plate and indirect Enzyme-Linked Immunosorbent Assay tests. Results: The apparent prevalence of brucellosis was higher in sheep (8.29%, 95% CI 6.7-10.1) than goats (5.82%, 95% CI 4.0-8.2). The true adjusted population level seroprevalence was also higher in sheep, at 7.7% (95% CI 6.0-9.6) than in goats, at 5.1% (95% CI 3.2-7.6). According to bivariate categorical analysis, six highly significant (p<0.001) animal- and farm-level risk factors for sheep were age, breed, number of lambings, history of abortion, rural farms, and presence of dogs on the farm. In goats, five significant risk factors were found: History of abortion, separate sheds, dogs on the farm, weekly veterinary consultation, and lack of brucellosis awareness. In a logistic regression model, abortion (OR adjusted 10.8, 95% CI 1.2-96.12), rural farms (OR adjusted 8.5, 95% CI 3.6-20.0), and absence of separate sheds on the farms (OR 1.9, 95% CI 1.1- 3.5) were found to be significant risk factors for ovine brucellosis. Conclusion: The use of complementary measures to tackle the multiple animal- and farm-level risk factors may help to reduce the disease burden in the absence of a vaccination policy for small ruminants in India.

Hemorrhagic septicemia (HS) is a highly contagious and fatal disease of cattle and buffaloes caused by P. multocida. Both conventional and molecular methods are applied in parallel for rapid diagnosis of HS outbreaks and the periodical surveillance strategy to identify risk areas for HS is ignored. The current cross-sectional study aimed to estimate sero-prevalence and associated risk factors for HS in cattle and buffaloes in non-vaccinated regions of two Indian states. HS surveillance was carried out through the multi-stage random sampling technique at different strata. The study employed a questionnaire incorporating host factors (species, breed, sex, age, and lactation) and demographic parameters (state, district, block/cluster and village/epiunits, and household). First, two Indian states known for high milk production were selected followed by two districts within each state, subsequently four clusters within each district, finally 5–10 epiunits within clusters and 5–8 households within clusters were randomly selected to collect cattle and buffalo samples. The chi-square/p values and maps were prepared to represent disease prevalence and to correlate disease risk factors at different strata. A total of 692 cattle and buffalo serum samples were sourced from two states of the country (Karnataka-285 and Gujarat-407). In the first strata, antibodies to P. multocida were high in Gujarat (14.49%, CI: 11.22–18.30) compared to Karnataka (3.85%, CI: 1.94–6.80) with significant (p < 0.0001) association between the states. In the second strata, one of the four districts investigated revealed the highest sero-prevalence (18.61%, CI: 13.81–24.24) with statistical significance (p = 0.01) between the districts. Among clusters, one out of eight clusters showed the highest sero-prevalence (23.02%, CI: 16.59–30.54) with statistical significance (p = 0.03) between the clusters in the third strata. At epiunit level (fourth strata), 9 out of 27 epiunits (33.33%) visited in Karnataka and 24 out of 29 epiunits sampled in Gujarat were sero-positive (82.75%) in iELISA. At the household level, out of 306 HH visited, 40 HH had at least one positive animal (13.07%) and the p value between HH in the two states was highly significant (p = 0.0002). Chi-square analysis did not find any association of HS sero-prevalence to species, age, and lactation. However, significantly higher (p < 0.05) sero-prevalence was recorded in indigenous cattle breeds (16.56%) compared to crossbreeds (6.59%). Various immunoprophylactics and antibiotic therapies are effective against HS, but inappropriate disease reporting and failure to implement adequate vaccination control measures are the gaps identified. The present study highlights the current scenario of HS sero-prevalence in two of the high milk-producing states of India, which will be useful for stakeholders for undertaking the implementation of surveillance and control strategies for the regions.

Background and Aim: Brucellosis is an infectious disease caused by Brucella species. This study aimed to identify the risk factors associated with bovine brucellosis seropositivity in organized dairy farms to control the disease in unvaccinated adult bovine herds in Karnataka, India. Materials and Methods: In total, 3610 samples (3221 cattle and 389 buffaloes) were subjected to parallel testing using the Rose Bengal plate test and protein G-based enzyme-linked immunosorbent assay, followed by analyses of animal- and farm-level epidemiological datasets to identify the risk factors. Results: The apparent brucellosis prevalence at the animal level was higher in buffaloes (8.2%, 95% confidence interval [CI] = 5.9–11.4) than in cattle (6.1%, 95% CI = 5.3–7.0). In a multivariable logistic model, animals calved 3–5 times (odds ratio [OR] = 2.22, 95% CI = 1.50–3.1, reference [ref]: animals calved <2 times); animals with a history of abortion (OR = 54.73, 95% CI = 33.66–89.02), repeat breeding (OR = 19.46, 95% CI = 11.72–32.25), and placental retention (OR = 13.94, 95% CI = 4.92–39.42, ref: no clinical signs); and dogs on farms (OR = 2.55, 95% CI = 1.48–4.40, ref: absence of dogs); disposal of aborted fetus in open fields (OR = 4.97, 95% CI = 1.93–12.84) and water bodies (OR = 2.22, 95% CI = 1.50–3.1, ref: buried); purchase of animals from other farms (OR = 6.46, 95% CI = 1.01–41.67, ref: government farms); hand milking (OR = 1.98, 95% CI = 1.02–10.0, ref: machine milking); and use of monthly veterinary services (OR = 3.45, 95% CI = 1.28–9.29, ref: weekly services) were considered significant risk factors for brucellosis in organized bovine herds (p < 0.01). Conclusion: The study identified that the animals calved 3–5 times or with a history of abortion/repeat breeding/placental retention, and disposal of aborted fetus in open fields/water bodies as the potential risk factors for bovine brucellosis. These risk factors should be controlled through the implementation of best practices to reduce the brucellosis burden in bovine farms. Keywords: brucellosis, buffalo, cattle, India, risk factors, seroprevalence.

Background: Brucella abortus S19 vaccination forms the cornerstone of the national brucellosis control program. Monitoring post-vaccination immune responses is crucial to assess vaccine performance across diverse regions and species. Methods: Two-phase nationwide seromonitoring study was conducted during 2021–2022 (Phase I) and 2022–2023 (Phase II) across seven geographical regions. A total of 51,759 serum samples were collected from S19-vaccinated cattle and buffalo calves of 4–8 months at four-days post-vaccination (DPV) intervals. Samples were analyzed using an in-house developed protein G-based indirect ELISA, and seroconversion rates were calculated. Statistical comparisons were performed, and spatial heterogeneity was mapped. Results: The overall seroconversion rate was 70.96%, with Phase I showing a higher seropositivity (76.05%) than Phase II (65.66%). Regionally, the Western (81.8%) and Southern (80.77%) regions showed the highest efficacy, while the Central region had the lowest (65.89%). Antibody kinetics peaked at 21–45 DPV (73.14%) and declined gradually to 43.27% by 91–120 DPV. A clear species effect was observed, with cattle calves showing higher seroconversion rates (77.12%) than buffalo calves (67.34%). Conclusions: This large-scale systematic evaluation highlights that S19 vaccine induces substantial seroconversion with regional, temporal, and species-specific differences. These insights provide crucial evidence for refining and strengthening India’s national brucellosis control program.

A comparative cross-sectional study was undertaken in organized and unorganized dairy sectors to evaluate the prevalence of bovine mastitis and the antibiotic resistance in Staphylococcus spp. of dairy animals and their associated personnel. A total of 391 households (HH) consisting of 211 and 180 HHs from organized and unorganized sectors, respectively, were selected based on 30-cluster sampling methodology in southern and northeastern regions of India. From 391 HHs, a total of 1920 milking cows (organized dairy—533; unorganized dairy—1387) were screened for subclinical and clinical mastitis by the California Mastitis Test (CMT). Out of 1920 milk samples, 1002 milk samples, 362 associated personnel hand and nasal swabs, and 27 milking machine swabs were sourced. The samples were subjected to Staphylococcus spp. by isolation and identification by multiplex polymerase chain reactions (mPCRs) and antibiotic sensitivity testing (ABST) to determine antimicrobial resistance (AMR) profiles. CMT results showed high mastitis prevalence (54.65%) in unorganized farms compared to organized ones (45.78%), with a significant association of mastitis to dairy sectors (p = 0.0004). On speciation, S. aureus isolates were comparatively less than those of coagulase-negative staphylococci (CoNS) (3.5% and 7.7%, respectively) in the organized dairy sector, and the same was recorded for the unorganized dairy sector (0.85% and 13.19%, respectively). In both the dairy sectors, the highest antibiotic resistance for Staphylococcus spp. was observed against the β-lactams (penicillins and cephalosporins) group (71.36% and 76.59%) and the lowest for nitrofurans (3.5% and 3%), oxazolidines (0.7% and 5.1%), and rifamycin (0.7% and 5.1%), respectively. In both the sectors, human isolates had comparatively high mecA positives (15.70% and 15.96%) compared to the animal isolates (8.36% and 12.94%). Based on mPCR, a smaller number of methicillin-resistant S. aureus (MRSA) isolates (3.95%) than methicillin-resistant coagulase-negative Staphylococci (MRCoNS) was detected in milk samples (6.05%), and the same was observed for associated personnel samples (MRCoNS (14.63%) compared to MRSA (1.05%)). In four HHs, mecA positives were detected in both animal and human samples, and this highlights the transmission dynamics of mecA between animals and humans in households. The resistance of Staphylococcus spp. to β-lactams highlights the need for cautious antibiotic use to prevent AMR.