Mastitis can be an important disease in sheep, with an incidence >2%. In addition to deaths from severe infections, the disease can be a cause of lamb mortality from starvation or of depressed weaning weights of lambs. Peracute, gangrenous (usually due to Staphylococcus aureus), acute, subacute, and probably subclinical types occur. The organisms most commonly involved are S aureus, coagulase-negative staphylococci, streptococci, Escherichia coli, Mannheimia haemolytica, and Trueperella (formerly Arcanobacterium) pyogenes.
The principles of diagnosis and treatment used in bovine mastitis Clinical Mastitis With few exceptions, mastitis occurs when microbes enter the teat via the teat canal. Almost any microbe can opportunistically invade the teat canal and cause mastitis. However, most infections... read more 
can be applied to ewes. Little is known about the control of ovine mastitis, but careful inspection of the mammary glands of ewes before mating to detect and eliminate those with chronic mastitis should be beneficial.
