Adaptive integumentary features of beef cattle raised on aforested or non‐shaded tropical pastures.

We aimed to analyze the seasonal acclimatization process of Nelore and Canchim cattle raised on two production systems (non-shaded, NS, and integrated crop-livestock-forest, ICLF), based on the dynamics of the morphological and functional attributes of the hair coat and skin during winter and summer...

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Bibliographic Details
Authors: BARRETO, A. DO N., JACINTHO, M. A. C., BARIONI JUNIOR, W., PEREIRA, A. M. F., COSTA, L. N., BRANDÃO, F. Z., ROMANELLO, N., AZEVEDO, G. N., GARCIA, A. R.
Format: article
Status:Published version
Publication Date:2024
Country:Brasil
Institution:Empresa Brasileira de Pesquisa Agropecuária (Embrapa)
Repository:Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice)
Language:English
OAI Identifier:oai:www.alice.cnptia.embrapa.br:doc/1170592
Online Access:http://www.alice.cnptia.embrapa.br/alice/handle/doc/1170592
https://doi.org/10.1038/s41598-024-66675-w
Access Level:Open access
Keyword:ILPF
ILCF
Seasonal acclimatization process
Production systems non-shaded
Hair coat
Skin
Intensive rotational grazing systems
Epidermal protection
Hair density
Thermoregulatory system
Gado Nelore
Gado Canchim
Bos Indicus
Bos Taurus
Beef cattle
Tropical pastures
Sweat glands
Description
Summary:We aimed to analyze the seasonal acclimatization process of Nelore and Canchim cattle raised on two production systems (non-shaded, NS, and integrated crop-livestock-forest, ICLF), based on the dynamics of the morphological and functional attributes of the hair coat and skin during winter and summer. The study was conducted in Brazil, in a low-altitude tropical climate region. A completely randomized 2 × 2 factorial design was adopted as follows: two production systems (NS and ICLF), two breeds (Nelore and Canchim) in a longitudinal structure, with measurements repeated over time through two stations (winter and summer). The experimental animals consisted of 32 Nelore (Bos indicus) and 32 Canchim (5/8 Bos taurus × 3/8 Bos indicus) bulls. The animals were equally distributed between two intensive rotational grazing systems. In both breeds, the hair coat was significantly thicker in winter but longer in summer, which increased epidermal protection. The Nelore bulls had shorter, wider, and thicker hairs, which are attributes that promote heat loss via conduction. The Canchim bulls showed significantly lower hair density and higher epithelium distance to sweat glands, which resulted in higher core temperature and respiratory rate. In turn, Nelore bulls had higher serum concentrations of triiodothyronine and lower serum concentrations of cortisol. However, Canchim bulls more frequently and intensely activated their thermoregulatory system and markedly adjusted their hair coat and hair features to reduce heat gain, especially in summer. Therefore, the anatomical plasticity and functional integumentary characteristics of Nelore and Canchim bulls reflect their acclimatization to tropical conditions.