|
|||||
|
|
Effects of an evaporative cooling system on plasma cortisol, IGF-I, and milk production in dairy cows in a tropical environment |
|
| Authors: | Cristiane Gonçalves Titto João Alberto Negrão Evaldo Antonio Lencioni Titto Taissa de Souza Canaes Rafael Martins Titto Alfredo Manuel Franco Pereira |
| Affiliation: | 1. Laboratório de Biometeorologia e Etologia, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de S?o Paulo/USP, Av. Duque de Caxias Norte, 225, Campus da USP, 13635-900, Pirassununga, SP, Brazil 2. Laboratório de Fisiologia da Lacta??o, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de S?o Paulo/USP, S?o Paulo, Brazil 3. Laboratório de Pesquisa em Bovinos de Leite, Faculdade de Medicina Veterinária e Zootecnia, Universidade de S?o Paulo/USP, S?o Paulo, Brazil 4. Instituto de Ciências Agrárias Mediterranicas, Universidade de évora, évora, Portugal |
| Abstract: | Access to an evaporative cooling system can increase production in dairy cows because of improved thermal comfort. This study aimed to evaluate the impact of ambient temperature on thermoregulation, plasma cortisol, insulin-like growth factor 1 (IGF-I), and productive status, and to determine the efficiency of an evaporative cooling system on physiological responses under different weather patterns. A total of 28 Holstein cows were divided into two groups, one with and the other without access to a cooling system with fans and mist in the free stall. The parameters were analyzed during morning (0700 hours) and afternoon milking (1430 hours) under five different weather patterns throughout the year (fall, winter, spring, dry summer, and rainy summer). Rectal temperature (RT), body surface temperature (BS), base of tail temperature (TT), and respiratory frequency (RF) were lower in the morning (P?P?=?0.11). Cortisol and IGF-I may have been influenced by the seasons, in opposite ways. Cortisol concentrations were higher in winter (P?P?P?P? |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ | |