TLDR Boxer and Labrador dogs' hair growth is affected by the tropical climate, but Schnauzers' is not.
The study investigated the hair follicle activity of 21 male dogs from three breeds (Boxer, Labrador, and Schnauzer) in Viçosa, Brazil, over 12 months. It found that Boxers and Labradors had a higher percentage of telogen hairs during hotter months and more anagen hairs during colder months, with mean telogen percentages of 93% and 90%, respectively. This indicated a significant correlation between hair cycle and environmental temperature and photoperiod for these breeds. However, Schnauzers, with a mean telogen percentage of 55.3%, did not show significant seasonal variation in hair cycle phases. The study concluded that the hair cycle of Boxer and Labrador dogs is influenced by environmental factors in a tropical climate, unlike Schnauzers.
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