The effect of vaccination on titres of antibody to rotavirus in colostrum and milk.

The continued presence of antibody to rotavirus in the gut of the neonatal ruminant has been shown to be important in protecting against clinical disease associated with rotavirus infections. This effect is dependant upon the amount of antibody included in the diet. Titres of antibody to rotavirus may be relatively high in ruminant mammary secretions immediately after parturition but decline rapidly over the course of the first day. The influence of vaccination on the titres of antibody, the concentrations of immunoglobulin and their respective of decline in the mammary secretion following parturition has been studied. Ewes vaccinated two to three weeks prior to mating with an inactivated preparation of lamb rotavirus produced colostrum and milk after the subsequent pregnancy which contained significantly higher titres of antibody to the virus than did the mammary secretions from non-vaccinates. The antibody activity appears to be associated with IgG and it is suggested that vaccination may be of value in the alleviation of neonatal diarrhoea associated with rotavirus infection in cattle and sheep.