Outbreak of Neonatal Diarrhea in Farmed Mink Kits (Mustella vison) Associated With Enterotoxigenic Staphylococcus delphini

Abstract

An outbreak of diarrhea on a large commercial mink farm affected 5,000 of 36,000 neonatal mink kits, with 2,000 dying within a 2-week period. Affected kits were severely dehydrated, and their furcoats and paws were covered with yellow- to green-tinged mucoid feces. On necropsy, the small intestines of examined animals were markedly distended by serous to mucoid fluid. Microscopically, there was prominent colonization of the intestinal villar epithelium by gram-positive bacterial cocci in the absence of inflammation and morphologic changes in villous enterocytes. The colonizing bacteria were phenotypically identified as belonging to the Staphylococcus intermedius group of bacteria. This was confirmed by nucleic acid sequence analysis of the 16S ribosomal RNA gene. Further nucleic acid sequencing of polymerase chain reaction (PCR) amplicons from the superoxide dismutase gene and the heat shock protein 60 gene differentiated the isolate as Staphylococcus delphini. Production of staphylococcal enterotoxins A and E was demonstrated with a commercial ELISA-based immunoassay. Sequencing of PCR amplicons confirmed the presence of the enterotoxin E gene, but PCR amplification of the enterotoxin A, B, C, or D genes was not successful. Although direct causation was not confirmed in this study, the authors postulate that the observed hypersecretory diarrhea in these mink kits was the result of colonization of the small intestine by S delphini and subsequent production of enterotoxin.

Mustelids

“…Mink, badgers, and ferrets are consistently culture-positive for S. delphini group A (Guardabassi et al, 2012). S. delphini infections cause hypersecretory diarrhea in ferret kits, while S. intermedius infection is associated with cutaneous adenitis and mastitis in mink (Hunter and Prescott, 1991;Sledge et al, 2010).…”

Genetic characterization of coagulase-positive staphylococci isolated from healthy pigeons

“…S. delphini as a coagulase-positive species should be regarded as an opportunistic pathogen. Similar to S. aureus and S. pseudintermedius, S. delphini produces a variety of virulence factors, including enzymes (coagulase, thermonuclease, proteases) and toxins (hemolysins, leukocidins, enterotoxins) (Sledge et al 2010, Ben Zakour et al 2012, Sudagidan and Aydin 2012, Gharsa et al 2014. The results of this research showed that S. aureus and S. delphini may be isolated from healthy pigeons.…”

“…delphini was initially isolated from a purulent skin lesions in dolphins (Voraldo et al 1988). Subsequently, this species was also found in a wide range of animals, including horses, mink, domestic pigeons, and recently it was isolated from donkeys (Hesselbarth and Schwarz 1995, Futagawa-Saito et al 2006, Futagawa-Saito et al 2007, Sledge et al 2010, Gharsa et al 2014. The phylogenetic analysis of nuc gene sequences revealed, that this species is formed by two genetically distinct groups (A and B) (Sasaki et al 2007).…”

The effect of color type on early wound healing in farmed mink (Neovison vison)

“…SIG comprises Staphylococcus intermedius, Staphylococcus pseudintermedius and Staphylococcus delphini group A and B [47], which could not be distinguished by MALDI-TOF MS. However, the isolates are most likely Staphylococcus delphini Group A [48], which has been reported to be an opportunistic pathogen in mink [48–50]. Whether the isolated bacteria were part of an early infectious process or just wound contaminants was not evident, though the presence of microabscesses and cellulitis in some wound specimens may indicate spreading infection.…”