Administration of Vaccines in Dairy Sheep and Goat Farms: Patterns of Vaccination, Associations with Health and Production Parameters, Predictors

This paper reports findings regarding patterns of vaccine usage in sheep and goat farms, in 325 sheep flocks and 119 goat herds throughout Greece. The objectives of the study were (a) to describe the patterns of vaccine administration in small ruminant farms and (b) to highlight factors that were associated with vaccinations in the farms. Vaccination against brucellosis was performed in all farms into the study. Among optional vaccinations, anti-clostridial vaccination was most frequently performed (in 97.8% of farms), followed by vaccination against contagious agalactia, (56.5% of farms), pneumonia (41.2%), chlamydial abortion (38.1%), staphylococcal mastitis (36.0%), and paratuberculosis (9.5%). Vaccinations against pneumonia and staphylococcal mastitis were performed more frequently in sheep flocks, whilst vaccinations against paratuberculosis were performed more frequently in goat herds. On average, 2.8 and 2.7 optional vaccinations (i.e., additionally to vaccination against brucellosis) were performed in sheep and goat farms, respectively. The increased number of vaccines administered was associated with a higher average milk production in the respective farms. There was an association of vaccination against staphylococcal mastitis with a reduced recovery of staphylococci from the bulk-tank raw milk. In multivariable analyses, significant associations of the administration of the various optional vaccines were seen with 15 variables, 11 related to health management practices and 4 related to the demographic characteristics of farmers; the collaboration with a veterinarian, the daily number of milking sessions, and the period spent daily by the farmer at the farm premises were each associated with the administration of vaccines against three infections.