Abstract :
Objective of the study was to evaluate the relationship between blood concentrations of
selenium, vitamin E and vitamin A with the incidence of acute clinical mastitis in dairy
sheep. For this purpose, 13 flocks with increased (≥10%) and five flocks with small (<3%) incidence
rate of clinical mastitis, were studied. In flocks with increased incidence rate, whole
blood selenium and serum vitamin A blood concentrations were smaller (P < 0.001) compared
with those in flocks with smaller incidence of the disease; no relationship between
vitamin E blood concentration and mastitis incidence was found. Animals with mastitis
associated with Staphylococcus aureus had smaller (P < 0.05) selenium, vitamin E and vitamin
A blood/serum concentrations compared to healthy animals within the same flock;
animals with mastitis associated with Mycoplasma agalactiae had smaller (P < 0.05) concentrations
of selenium and vitamin A compared to healthy animals within the same flock
(P < 0.05); finally, animals with mastitis associated with coagulase-negative staphylococci
had smaller (P < 0.05) concentrations of selenium compared to healthy animals within the
same flock. The results indicate a possible predisposing role of Se deficiency in ovine mastitis.
Selenium status of ewes may possibly be used to indicate animals at risk to develop
clinical mastitis. Reduced vitamin A serum concentration may also contribute to development
of clinical mastitis.
