Generalized tympanism in a horse and its possible association with Sarcina-like microorganism: A case report.

Background: Sarcina spp. is a Gram-positive, coccoid microorganism that forms tetrads or octets, and is observed with a characteristic "bundle" arrangement. The most recognized species are Sarcina ventriculi and Sarcina maxima. It has been described as part of the normal microbiota in horses and cats, but it has also been linked to abomasal bloat in goats, lambs, and calves, although its causality has not been proven yet. Case Description: This work presents the case of a 3-months-old female horse that died of generalized tympanism. Macroscopic findings showed mild cyanosis and abundant gas in the lumen of the stomach, and small and large bowel. Microscopically, high numbers of Gram-positive microorganisms compatible with Sarcina spp. in the gastric lumen and on the surface of the small and large bowel were observed, along with mild inflammation. Conclusion: The severe tympanism was the only relevant lesion observed and could explain the death of the animal. Although it is not possible to determine a relationship between these lesions and Sarcina spp., it is interesting to highlight that the high amount of these bacteria could be associated with gas production and tympanism. It is important to continue investigating the role of Sarcina spp. in horses, and its possible link with tympanism.

First report of a subcutaneous infection by Cryptococcus neoformans (former Cryptococcus neoformans var. grubii) in a cat in Costa Rica.

This is a case report of a feline animal that presented with a skin infection on the neck from which Cryptococcus neoformans (former C. neoformans var. grubii) was isolated and identified. The cat presented two nodular tumors, approximately 2 cm in diameter, raised, solid, with a slightly irregular surface and a reddish color with white areas. Histologically, these tumors corresponded to granulomatous dermatitis and panniculitis with the presence of a large number of intralesional yeasts. From identification with biochemical and spectroscopic techniques of these lesion samples, it was determined that the etiological agent was C. neoformans. There is little information on this variety of Cryptococcus causing subcutaneous infection without involvement of other organs, and the presence of this pathogen in the few reports available has not been reliably determined. This is the first report of a cat affected by C. neoformans in Costa Rica.

Bactericidal activity of lachrymal secretion and complement system in copper deficient bovines.

Copper deficiency in humans and animals has been related to increased susceptibility to infections. Neutrophils are one of the most studied components of the immune response; however, to the best of our knowledge, other defenses of the innate immune system have not been analyzed in copper-deficient animals. Our previous studies in copper-deficient bovines have shown increased susceptibility to infectious keratoconjunctivitis, an ocular disease caused by Moraxella bovis. The objective of this work was to evaluate the bactericidal activity of lachrymal secretion and complement system, two main mechanisms of the innate immune response against M. bovis, in copper-deficient cattle. Our results indicate that copper deficiency has no effect on bactericidal activity of complement system and lachrymal secretion against M. bovis in calves. Other components of local and systemic ocular defense mechanisms that could explain the increased susceptibility to infectious keratoconjunctivitis observed in copper-deficient bovines should be investigated.