An in vitro study to determine the minimal bactericidal concentration of sodium hypochlorite (bleach) required to inhibit meticillin-resistant Staphylococcus pseudintermedius strains isolated from canine skin.

BACKGROUND: Meticillin-resistant Staphylococcus pseudintermedius (MRSP) is becoming a more common pathogen in animals treated in veterinary hospitals, raising concerns for transmission and possible contamination of the hospital itself. The identification of effective agents for the decontamination of veterinary patients and hospitals is crucial. Sodium hypochlorite (6.15%) or 'bleach' is an inexpensive and frequently used decontamination agent in human and veterinary hospitals and an adjunctive treatment for human patients. There are no published data on the minimal bactericidal concentration (MBC) of sodium hypochlorite (6.15%) for MRSP. HYPOTHESIS/OBJECTIVES: The objective of this study was to determine the MBC of sodium hypochlorite (6.15%) against MRSP strains isolated from canine skin. METHODS: In this in vitro study, 12 canine skin isolates were obtained from the Antech Diagnostics microbiology department. Twofold serial dilutions of sodium hypochlorite (6.15%) were allowed to react with each of the MRSP strains for 15 min, followed by overnight incubation on agar plates. Colonies on each plate were counted. This process was repeated in triplicate. RESULTS: The overall MBC for the canine skin-isolated MRSP strains was 1:32, but most strains had an MBC between 1:64 and 1:128 dilution. CONCLUSIONS AND CLINICAL IMPORTANCE: This study shows that sodium hypochlorite (6.15%) is an effective agent for decontamination at easily achievable concentrations.

Ulcerative enterocolitis in two goats associated with enterotoxin- and beta2 toxin-positive Clostridium perfringens type D.

Enterotoxemia caused by Clostridium perfringens type D in sheep is believed to result from the action of epsilon toxin (ETX). However, the sole role of ETX in the intestinal changes of the acute and chronic forms of enterotoxemia in goats remains controversial, and the synergistic action of other C. perfringens toxins has been suggested previously. The current study examined 2 goats that were found dead without premonitory clinical signs. Gross lesions at necropsy consisted of multifocal fibrinonecrotic enterocolitis, edematous lungs, and excess pleural fluid. Histologically, there were multifocal fibrinonecrotic and ulcerative ileitis and colitis, edema of the colonic serosa, and proteinaceous interstitial edema of the lungs. Clostridium perfringens type D carrying the genes for enterotoxin (CPE) and beta2 toxin (CPB2) was cultured from intestinal content and feces of 1 of 2 goats, while C. perfringens type D CPB2-positive was isolated from the other animal. When multiple colonies of the primary isolations from both animals were tested by Western blot, most of the isolates expressed CPB2, and only a few isolates from the first case expressed CPE. Alpha toxin and ETX were detected in ileal and colonic contents and feces of both animals by antigen capture enzyme-linked immunosorbent assay. CPB2, but not CPE, was identified in the small and large intestines of both goats by immunohistochemistry. These findings indicate that CPB2 may have contributed to the necrotic changes observed in the intestine, possibly assisting ETX transit across the intestinal mucosa.

Abortion and ulcerative posthitis associated with caprine herpesvirus-1 infection in goats in California.

Three outbreaks of late-gestation abortions in does and ulcerative posthitis in bucks, associated with caprine herpes virus-1 (CHV-1), in California are described. In herd A, 10 of 17 does aborted in a 7-day period, whereas in herd B, 4 of 130 does aborted in a 45-day period and in herd C, 100 of 300 does aborted in a 3-week period. Most fetuses had multifocal pinpoint depressed foci with a zone of hyperemia on external and cut surfaces of the kidneys, liver, lungs, and adrenal glands. Histologically, scattered multifocal areas of necrosis with mild neutrophilic infiltrate were observed in kidneys, brain, liver, adrenal glands, and lungs of most fetuses of the 3 herds. Large amphophilic intranuclear inclusion bodies, which displaced the chromatin, were observed in cells within and around the necrotic foci in kidneys and adrenal glands. Particles 85-113 nm in size with morphology compatible with herpes virus were observed in the nuclei of these cells when examined by electron microscopy. Irregular, shallow, red ulcers were observed in the prepuce of 1 buck from herd C. Prepuce biopsies from this animal had necrosis of the superficial mucosal epithelium and severe submucosal lymphoplasmocytic infiltrates. Large intranuclear amphophilic inclusion bodies were observed in most cells of the stratum spinosum of the preputial epithelium, but no viral particles were observed in these cells. Caprine herpes virus-1 was isolated from tissue pools of fetuses from the 3 herds but not from prepuce biopsies. Positive results were obtained when tissues of a fetus from herd C were processed by a polymerase chain reaction technique to amplify the amino terminus of the glycoprotein C gene of CHV-1. Sera from aborted does from herds B and C and from the 3 bucks from herd C had high antibody titers to CHV-1. The results presented here support the hypothesis that the male goat is involved in the transmission of CHV-1. However, other forms of transmission cannot be ruled out.