Introduction

Tegumentary system pathologies have a vast importance in small animal practices medicine (Mazzei et al. 2002). Weidman (1925) isolated a lipophilic dependent yeast with "bottle" form from skin lesions of Indian rhinoceros, first called Pityrosporum pachydermatis and now known as Malassezia pachydermatis (Sloof 1971 & McGinnis 1980). M. pachydermatis is lipophilic saprophytic-no-mycelial yeast, frequently found in normal skin, hearing ducts, anal sacks and in rectum and vagina of dogs and cats (Scott et al. 1995). Environment factors as temperature, humidity and substratum stimulate the yeast growth and transformation from no parasite form to the parasitism (Fraser 1965; Larsson et. al 1988; Lobel et al. 1995). The cases reported were referred to the Veterinary Hospital of Rural Federal University of Amazonian (UFRA) between January 2006 and December 2007. Tropical clime, prevalent in the Amazonian region where UFRA is localized, is characterized by high temperature, increase humidity and great deal of substratum aiding the yeast multiplication and dermatitis cases appearing. The objective of the present paper is analyze and quantify Malassezia pachydermatis from collected skin lesion materials of canines attended in Veterinary Hospital of UFRA during a twenty-four month period, from January 2006 to December 2007.

Materials and Methods

The canines attended at the Veterinary Hospital and selected to this paper had as principal complaint skin diseases and was constituted by 216 animals. There was no old, weight or race distinguishes between the studied animals. The analyzed material was collected in glass blades by techniques of skin scratch and skin imprint, during clinical exams, retreated from many different areas but principally from earring pavilion. After collection the materials were colored with a special pigment called "Panoptic" (Instant-Prov®) at Veterinary Clinical Laboratory (UFRA). The pigmented materials were examined to the optical microscope in immersion lens and the final results referred the media of each blade analysis. Criterions were established to evaluate Malassezia pachydermatis presence: 1) Rare: presence of 1-3 units of yeans for microscopy field in few fields. 2) Moderate: presence of 4-6 units for field. 3) Frequent: presence of 7-10 units for field. 4) Abundant: presence 11 or more units for field.

Results

The 83 (99.99%) exams realized in 2006 diagnosed the presence of M. pachydermatis in 80 animals, classified from rare to abundant presence: 43 (51.81%) exams classified as rare presence, 3 (3.61%) as moderate, 27 (32.53%) as frequent and 7 (8.43%) as abundant. There were 3 (3.61%) negative exams and the "rare" classification was the most found in referenced year. At 2007, 133 (100%) exams were consummated, with 121 positive diagnoses to the yeast: 35 (26.32%) exams classified as rare presence, 3 (2.26%) as moderated, 55 (41.35%) as frequent and 28 (21.05%) as abundant. 12 (9.02%) exams had negative presence of the yeast and "frequent" classification were the commonly exam analyzed (Table 1). In total, 216 dogs were part of the studied group and 201 of them were diagnosed with Malassezia pachydermatis present by the collected material.

Table 1. Occurrence of Malassezia pachydermatis in canines attended in Veterinary Hospital of Rural Federal University of Amazonian between January 2006 and December 2007.

Conclusion

The elevated number of affective dogs by M. pachydermatis diagnosed in the study reflects environment conditions from tropical clime: high substrate, humidity and temperature indexes, favoring yeast growth and its pathological form. The few cost of veterinary clinical attendant in UFRA selects reductive lacework population that a lot of times don't have an appropriate knowledge about sanity and health. The absence of information and financial conditions impedes correct care with animals, by the way those proprietors cannot pay for good products and a veterinarian at the diseases began. The development of social programs aiming the population awareness and efficient treatments with low costs are extremely important to improve not just the health but also the life of domestic animals.

References

1.  Fraser GA. 1965. The etiology of otitis expresses in the dog. Journal of Small Animal Practice. 6: 445.

2.  Larsson CE, Larsson MHMA, Amaral RC, et al. 1988. Dermatitis in dogs caused by Malassezia (Pityrosporum) pachydermatis. Veterinary Ars. 4: 63-68.

3.  Lobel R, Weingarten A, Simmons R. A new agent for the treatment of the canine otite. The Veterinary Hour. 88: 29-33.

4.  McGinnis RM. 1980. Synopsis of the mycoses: Pityriasis versicolor. In: Laboratory Handbook of Medical Mycology. London. Academis Press. 475-522.

5.  Scott DW, Miller WH, Griffin CE. 1995. Dermatology of Small Animals, 5th ed. Interlivros, Rio of Janeiro, p.321-323.

6.  Sloof WC. 1971. Pityrosporum sabouraud, p.1167-1186. In: Lodder J. (Ed.), The Yeasts. 2nd ed. Amsterdam, North Holland.

7.  Weidman FD. 1925. Exfoliative dermatitis in Indian rhinoceros (Rhinoceros unicornis) with the description of the new specie: Pityrosporum pachydermatis, p.36-43. In: Report Zool Soc Lab Comp Pathol, Philadelphia.