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SUMMARY Tests indicate that, following selenite enrichment, Salmonella dublin would be isolated from rectal swabs taken from animals excreting 100 S. dublin organisms/g faeces. Even lower numbers of excreted organisms should often he detected. Thirty-eight of 183 calves under three months old examined post mortem yielded S. dublin and seventeen (44 · 7 per cent) of the thirty-eight gave cultures of S. dublin from rectal swabs. In three cases, rectal swabs were positive from calves with negative intestinal cultures, and on four occasions the reverse was true. In fourteen cases both rectal swabs and intestinal cultures were positive. S. dublin appears to be excreted in the saliva of sick calves.

SUMMARY A killed toxoplasma vaccine prevented foetal death in a proportion of ewes which were challenged during subsequent pregnancy; it did not prevent foetal or placental infection. Pregnancy was more frequently normal in those ewes with higher dye-test antibody titres at the time of challenge. Also, the earlier in pregnancy the challenge was given, the greater was the likelihood of foetal death. Ewes which had dead lambs had higher post-partum antibody titres than those which had live lambs. The indirect fluorescent antibody test proved to be the most sensitive method for demonstrating infection in the products of conception. Histopathological changes were predominantly in the placenta; only minor lesions were found in the dead lambs and these were no more severe than in the lambs born alive.