1. Milk yield in Holstein cows and physiological responses in hot environment
- Author
-
Jacinara Hody Gurgel Morais Leite, Débora Andréa Evangelista Façanha, Ângela Maria de Vasconcelos, Josiel Ferreira, Wirton Peixoto Costa, and Magda Maria Guilhermino
- Subjects
Wet season ,General Veterinary ,0402 animal and dairy science ,food and beverages ,Humidity ,Collection period ,Rectal temperature ,04 agricultural and veterinary sciences ,Biology ,040201 dairy & animal science ,Breed ,Physiological responses ,Interaction time ,03 medical and health sciences ,0302 clinical medicine ,Animal science ,Dry season ,030217 neurology & neurosurgery - Abstract
This study is aimed to evaluate the physiological responses and the production of milk cows of the Holstein breed, pure, in the dry and rainy seasons. During the period from March to October rectal temperature (TR), respiratory rate (FR) and milk production (PL) were taken at 7 am and at 3 pm twice a week, in eleven cows. At the same time, in these cows there were also recorded temperatures of air and black globe, humidity and it was calculated the Globe and Humidity Temperature Index (ITGU). Statistical analyzes were performed by the method of least squares and this revealed significant effects of the animal, also the year of the period and month collection period within the year on the variables recorded, with higher TR and FR during the rainy season, when the PL was higher. There was a significant time interaction and animals just for the PL and the interaction time of collection and time for PL and TR. The effects of ITGU in the shade and the sun were different only concerning the FR. Milk production was extremely low in all periods of the year and in the dry season, in the afternoon, there was a higher body heat, and in the rainy season the use of the mechanisms of respiratory evaporative heat loss was intensified.
- Published
- 2016