Alopecia in bats: a case study of four species from Mexico

Alopecia, or alopecia syndrome is the partial or complete loss of hair from an animal's body. Following a previous report on bats with alopecia, in this work we complemented the list of bat species with alopecia available in the literature through 2023, adding phyllostomids (Artibeus planirostris, Carollia perspicillata), an emballonurid (Peropteryx pallidoptera), molossids (Molossus rufus, Nyctinomops macrotis), and vespertilionids (Corynorhinus rafinesquii, Eptesicus fuscus, Nycticeius humeralis, Myotis austroriparius, M. grisescens, M. velifer). We also explored factors that may explain alopecia in the first records of this condition in ten Pteronotus mesoamericanus females from Oaxaca, southeastern Mexico, recorded from November 2020 to January 2022. In those individuals, hair loss was observed on the back and head; six of them were lactating and four showed no evidence of reproductive activity. In addition, we documented alopecia on the thorax in four individuals of three species: Artibeus lituratus (one pregnant female and one male with scrotal testes), Pteronotus fulvus (one pregnant female), and Artibeus toltecus (one pregnant female). The alopecic bats presented mild alopecia (the affected area ranged from 1-5 cm2), and only one female showed moderate alopecia (8.1 cm(2)). Alopecia in P. mesoamericanus, P. fulvus, A. toltecus, and A. lituratus may be due to hormonal or nutritional imbalances associated with reproduction. In addition, in A. lituratus it may also be the result of environmental stress when foraging in an urban area. The causal agents of alopecia in bats are still not fully known, and it is probably a multifactorial phenomenon.

Automated summary

Alopecia, the loss of hair, is found in various bat species. The potential causes of Alopecia in bats include hormonal imbalance and nutritional deficiencies. However, the exact underlying factors of Alopecia in bats remain unknown.