A PRELIMINARY NOTE ON THE INTERNAL PARASITES OF PUERTO RICAN CATTLE WITH SPECIAL REFERENCE TO THOSE SPECIES FOUND IN CALVES SUFFERING FROM "TROPICAL DIARRHEA"

Abstract

The results of a survey of the internal parasites of Puerto Rican cattle made as a preliminary step in connection with investigations on "tropical diarrhea" in calves have shown that the four most common species of gastro-intestinal parasites in the 22 calves autopsied were, B. phlebotomum (77.3%), O. radiatum (63.6%), C. punctata (54.5%), and H. contortus (50%). Eight of the 22 calves and one calf not autopsied were found to be suffering from "tropical diarrhea." These nine calves were from 2 to 11 months old and were about evenly divided between the central mountainous section and the north and south coastal plains. Eight of the nine cases occurred during the first 3 months of the calendar year. One occurred in June. E. zurni, together with the four species of nematodes just mentioned were recovered in large numbers from calves suffering from "tropical diarrhea.". The nematode, S. papillosus, was also implicated in one case as the result of finding large numbers of eggs in the feces of a calf. The remainder of the 21 species of parasites listed, with the exception of the lung worm, D. viviparus, which was found to be the cause of verminous pneumonia in 3 calves, were considered to be of little pathogenic importance in the calves examined.