Fatal candidiasis in a wild red squirrel (Sciurus vulgaris)

Abstract

Candida species are commonly present as commensal organisms in the alimentary tract of mammals and birds, but they are also opportunistic pathogens. Many species may cause disease, but the great majority of cases in both human beings and animals are due to Candida albicans. This is a dimorphic fungus, existing either as typical budding yeast cells or as fungal hyphae. Infection is usually superficial and typically causes necrotic, diphtheritic lesions of mucous membranes, particularly those of the buccal cavity and oesophagus where they are known as moniliasis or thrush. While candidiasis is a common condition of human beings and captive primates, there are relatively few reports of it in animals. This short communication describes a case of candidiasis in a red squirrel (Sciurus vulgaris). In July 2007 a juvenile red squirrel was found in weak condition near Dundee. It was given a small amount of cow's milk by syringe and then admitted to a wildlife rehabilitation centre. Here it was fed powdered puppy milk with 0•2 ml of 2•5 per cent enrofloxacin (Baytril; Bayer) and 0•1 ml of 0•1 per cent ivermectin (Ivomec; Merial). It was also sprayed with 0•25 per cent fipronil (Frontline; Merial). The squirrel's condition did not improve and it died the following day. It was submitted to the Wildlife Veterinary Investigation Centre for postmortem examination. The squirrel was male, weighed 125•2 g and measured 33•3 cm from nose to tail tip. Based on its size and the fact that it had a full tail, it was estimated to be around 10 to 12 weeks old. The squirrel's coat condition was fair but numerous lice were seen on the ventral body surface. Body condition was poor and there was no subcutaneous fat. The mucosa at and around the base of the tongue and the larynx was brownish, raised and irregular. The oesophagus was markedly thickened and inflamed along its full length and the mucosa was pale and necrotic. The stomach was full of whitish, pasty material and the mucosa appeared normal. The intestines were affected by moderate autolysis, but no lesions were seen and the contents looked normal. The trachea contained clear froth and the right lung was moderately congested. The liver was pale, and the spleen was pale and small. No lesions were observed in the thyroid glands, thymus, heart, kid

Causes of mortality and pathological lesions observed post-mortem in red squirrels (Sciurus vulgaris) in Great Britain

“…Lingual and laryngopharyngeal necrotising ulceration associated with S. aureus infection was considered to have predisposed to inhalation pneumonia in a juvenile squirrel on IoW and oropharyngeal/oesophageal candidiasis caused the death of a juvenile from Scotland. (For further detail see Simpson et al [6]). Gastritis in a second juvenile from Scotland was associated histologically with a yeast infection but although the organism was isolated it could not be identified by API test.…”

Epidemiological and postmortem findings in 262 red squirrels (Sciurus vulgaris) in Scotland, 2005 to 2009

“…Other previously reported causes of mortality in red squirrels include predation, starvation, extreme cold weather, parasitic disease, failure to thrive after weaning, stress after relocation, neoplasia, nutritional disease and human activities (road traffic casualties) (Keymer 1983, Kenward and Hodder 1998, Lurz and others 2005, Simpson and others 2006). There have also been occasional case studies on the causes of death and disease in individual red squirrels in the UK (Duff and others 2007, Simpson and others 2009). However, there has been no comprehensive study to examine and quantify the causes of death in a larger sample size of red squirrels in Scotland.…”

A Peek into the Bacterial Microbiome of the Eurasian Red Squirrel (Sciurus vulgaris)

“…E.coli strains with low pathogenicity were previously isolated from S. vulgaris in a case of mortality due to cestode parasitism [ 58 ]. Its presence in the red squirrel has also been reported in a case of fatal candidiasis [ 59 ]. Strains of non-haemolytic E. coli , along with S. aureus , have been identified from various body sites of carcasses recovered from the wild in the UK [ 60 ].…”