Clinicopathological evaluation of non-parasitic dermatoses in canines

The present study has been carried out to detect non-parasitic dermatoses in canines brought at the Nandini Veterinary Hospital, Surat.

The current investigation was carried out on skin scrapping, skin biopsy specimens, blood, and serum samples of 210 freshly registered cases of dogs with dermatological afflictions. Dogs found healthy on clinical examination were used as control animals (n=15). The incidence of non-parasitic dermatoses has been recorded as per age, breed, and sex of dogs. For bacterial isolation, the pus/exudates samples were collected from 40 cases of pyoderma and streaked onto brain-heart infusion agar while 13 skin scrapping samples were inoculated on Sabouraud's dextrose agar with chloramphenicol for isolation of fungi. The organisms were identified on the basis of gross and microscopic observation of cultural growth on media. The blood and sera samples were also collected to note alteration in hematology and biochemical parameters, respectively. Tissue samples from lesions were collected and subsequently preserved in 10% neutral buffered formalin for histopathology.

Out of 210 cases of dermatoses, 60 cases were of non-parasitic dermatoses, i.e., 28.57%. Of these, bacterial skin infections (pyoderma) were found to be the predominant at 80.00%, followed by other non-parasitic dermatological disorders, i.e., 11.67% and fungal skin infection, i.e., 8.33%. The dogs belonging to age group 1-3 years showed greater susceptibility to non-parasitic dermatological conditions. Breed wise incidence of pyoderma was found more in the Pomeranian breed (20.83%), whereas fungal skin affections were found to be higher in mongrel breed (60.00% and 42.86%, respectively). Male dogs showed greater involvement in bacterial, fungal, and other non-parasitic dermatoses. Bacteriological culture examination of 40 pus swabs resulted in the growth of 39 bacterial isolates. Mycological culture of skin scrapings from 13 suspected cases of fungal dermatoses resulted in the recovery of five fungal isolates. Hematological and serum biochemical parameters revealed a significant difference in all cases of non-parasitic dermatoses.Histopathological study revealed characteristic changes like infiltration of neutrophils with perifolliculitis, hyperkeratosis, and rafts of acantholytic cells. Histochemical staining revealed purple or magenta color fungal elements.

Based on current experiment it has been concluded that among non-parasitic dermatoses bacterial and fungal skin infections are the main ailments, followed by nutritional and other causes in adult and male dogs which can be diagnosed by cultural inoculation, microscopic examination of skin scrapings, and dermatohistopathology along with hematology and biochemistry.