Staphylococcus aureus mastitis in Texel sheep associated with suckling twins

During the lactation period, the udder and milk of the sheep were examined by the farmer when any indication of possible udder problems, such as ewes showing general signs of illness, bleating lambs (a sign of hunger, as they were not getting enough milk) or obvious abnormalities of the udder, were observed. Another logistic regression model was built on a subset of the data, including only the cases of mastitis caused by S aureus or M haemolytica, to test the hypothesis that the odds of infection with S aureus versus M haemolytica in ewes that suckled twins or triplets was equal to the odds in ewes suckling one lamb, corrected for parity as a possible confounder.