A preliminary study reported larger sweat glands cross-sectional cut areas (ASW) in slick-haired Holstein cows (SLICK) than in their wild-type (WT) counterparts. Being Holstein a breed developed under temperate weather conditions, the present study aimed to evaluate how such values compare with those in Senepol (SEN), a Bos taurus breed, slick-haired and highly adapted to the tropical weather. Hair coat types were visually chosen and genetically confirmed. Skin biopsies (n = 1 / cow; 6 mm in diameter) were obtained from 9 SLICK (2.4 ± 0.17 lactations; 569.9 ± 11.39 kg of body weight (BW)), 8 WT (3.7 ± 0.26 lactations; 645.8 ± 12.16 kg of BW) and 9 SEN cows (7.4 ± 0.47 lactations; 610.6 ± 18.28 kg of BW) behind the right shoulder after local anesthesia. Biopsies were immediately preserved in 10% formalin, embedded in paraffin, cut perpendicularly to the skin layers (7 µm thickness), and stained with hematoxylin-eosin in microscope slides. A total of 6 skin cuts per cow were randomly selected and the ASW (10–100 / cut) was evaluated using the NIS Element D Software (Nikon, Melville, NY) under 4x magnification. Data were averaged by skin cut (PROC MEANS) and compared between hair type/breed groups (PROC GLIMMIX) using SAS. Without considering the SEN cows, the ASW values were larger in the SLICK than in the WT cows (6,946.16 ± 623.10 and 4,902.67 ± 588.15 µm², respectively; P = 0.0307). However, when included in the data set, SEN cows had the largest ASW (9,651.74 ± 868.89 µm²; P = 0.0031), while no differences were observed between the SLICK and WT cows. The present study corroborates a larger sweat gland size in the SLICK than in the WT cows; however, these are smaller than what is found in a well-adapted tropical breed such as SEN. Future studies should evaluate if a larger sweat gland implies greater heat dissipation via evaporation.