Abstract. Of 45 piglets with diarrhea, 28 had coccidiosis, with no evidence of concurrent viral infection. Villous atrophy and necrotic enteritis were the characteristic lesions, and were more severe in piglets with combined viral and coccidial infections than with coccidiosis alone. Necrotic enteritis presumably was caused by bacterial invasion of the villous lamina propria at foci denuded of epithelium by coccidia, viruses or both. Consistent lesions associated with coccidia in piglets not infected by other primary enteric pathogens suggest that coccidia are the cause of significant clinical disease in nursing piglets 6 to 15 days old.

Abstract. Spontaneous enteric disease characterized by hemorrhagic diarrhea and high mortality occurred in puppies from commercial kennels in three midwestern states. Microscopic lesions resembling those of panleukopenia in cats were seen in the intestines. The predominant features were necrosis of crypt epithelium, collapse or dilation of crypt lumina and villous atrophy. Viral particles morphologically resembling parvovirus were found in the feces by direct electron microscopy. The canine virus reacted with antibody to feline panleukopenia virus by immunoelectron microscopy and fluorescent antibody technique. Fluorescent antibody was used to detect virus in the crypt epithelium of affected dogs. Feline kidney cells inoculated with fecal preparations had cytopathic effect and positive fluorescence by fluorescent antibody technique.Widespread outbreaks of severe enteric disease associated with a parvovirus-like agent occurred in dogs throughout the United States and Canada in 1978 [2, 5, 7, 191. Although a parvovirus was isolated from asymptomatic dogs in 1970 [6], the first association of parvovirus with canine diarrhea was made in 1977 (81.Intestinal infections with parvovirus have been associated with enteric disease in cats [lo, 121 and calves [l, 3, 171. Feline panleukopenia is caused by a parvovirus, and the distinctive histologic lesions are attributed to the requirement for rapidly dividing cells for viral replication [l 1, 141. Infected cells must proceed through the DNA synthesis phase of the cell cycle before replication of the parvovirus can occur [9, 11,16, 181. The canine enteric disease seems to bear more than superficial resemblance to feline panleukopenia. Leukopenia is a common feature in affected dogs, and the enteritis is characterized by involvement of the intestinal crypts (2, 5, Materials and MethodsThe material for this study was from five dogs submitted for necropsy and specimens of formalin-ftxed and refrigerated tissues from five additional dogs. Tissues for histologic evaluation were ftxed in neutral buffered to% formalin and routinely processed. Paraffmembedded sections were cut at 7 micrometers and stained with hematoxylin and eosin (HE).Intestinal contents were collected from seven dogs from which fresh or refrigerated viscera were available. The samples were prepared for negative contrast electron microscopy as described (41. For immunoelectron microscopy three drops of the fecal preparation were mixed with three drops of feline panleukopenia virus antiserum and incubated overnight at 4OC. 68071.

The possible role of Neospora caninum and other abortogenic infectious agents in dairy cattle abortions was evaluated utilizing samples collected from 9 herds in the Lima Valley between January 1998 and December 1999. Heart, liver, lung, muscle, thymus, spleen, adrenal gland, brain and thoracic fluid samples were taken from 29 aborted 3-7 month gestation fetuses, and serum samples were collected from their mothers. The presence of anti gens and antibodies against N. caninum, bovine cliarrhea virus (BVDV), Bruce/la abortus and Leptospira was determined utilizing immunoperoxidase, immunofluorescence, virus neutralisation, indirect ELISA and microaglutination tests respectively. One half ofthe tissue samples were fixed for histopathological examination. Of the aborted fetuses, 55.2% (16/29) and 20.6% (6/29) were positive to N. caninum antigen and BVDV. N. caninum antibodies with titers between 1 :20 and 1 :40 were detected in three of the fetuses, but no antibodies against BVDV or Leptospira were found. Antibodies against N. caninum and BVDV were detected in 62% ( 18/29) and 72.4% (21/ 29) of the aborted cows. No antibodies against either Bruce/la abortus or the Leptospira serovars canicola, pomo na, icterohemorrhagiae, and hardjo were detected. Two of the fetuses had histopathological lesions (moderate inflammation with small areas of necrotic tissue in the brain, heart, muscle and thymus tissues) similar to those described in the literature. The high prevalence of N. caninum antigen in fetuses from positive cows and the moderate presence of BVDV contrasts with the absence of other abortogenic agents, strongly suggesting an association of N. caninum with the high incidence of abortion in dairy cows from the Lima Valley.