Estudo do ciclo piloso em cães de diferentes pelames em região de clima tropical no Brasil

• Autor(a) principal: Favarato, Evandro Silva
• Data de Publicação: 2006
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5077
• topic: Cão; Telógeno; Anágeno; Dogs; Telogen; Anagen; CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA::CLINICA E CIRURGIA ANIMAL::CLINICA VETERINARIA

The hair cycle has been extensively studied in humans, sheep and laboratory animals, however there is a lack of studies on dogs. Besides varying according to the species, breed, sex and general health conditions, the hair cycle is mainly affected by climatic variations. The objective of the present work was to analyze and increase our understanding of the hair cycle in three dog breeds with different coats, in the city of Viçosa-MG (latitude -20°45'), in different seasons throughout the year. A total of 21 male healthy dogs, distributed in 3 groups according to coat type, were used in the study. The group Boxer (GB) represented the short-hair coat type consisting of six Boxer dogs, the group Labrador (GL) represented the medium-length-hair coat type consisting of eight Labrador dogs, and the group Schnauzer (GS) represented the long-hair coat type consisting of seven Schnauzer dogs. Hair samples were collected monthly from the area of the shouder over a one-year time period. The trichogram evaluation was used to identify the hair cycle phases through the morphological analysis of hair follicles. The environmental temperature and photoperiod duration in Viçosa-MG were obtained and compared with telogen and anagen hair numbers of the animals in study. Boxer and Labrador dogs showed a larger number of telogen hairs than Schnauzer dogs, and it was found that the cyclic activity of hair follicles in Boxer and Labrador dogs are associated mainly with the variation in the environmental temperature and in a lesser degree with the photoperiod variation, however, apparently the same did not happen with Schnauzers. In addition, it was found that Boxers and Labradors had a larger number of telogen hairs during the hottest months of the year, and an increase in anagen hairs during the coldest months. There was no difference for telogen and anagen hair numbers in the hottest and coldest periods of the year for Schnauzers.