Data/hora: 13/06/2024 01:27:41

Provedor de dados: 	117	
País: 	Chile	
Título: 	Influence of Water Temperature and Heat Stress on Drinking Water Intake in Dairy Cows	
Autores: 	González Pereyra,Ana Valeria; Maldonado May,Verónica; Catracchia,Carlos Guillermo; Herrero,María Alejandra; Flores,Myriam Celina; Mazzini,Mariana.	
Data: 	2010-06-01	
Ano: 	2010	
Palavras-chave: 	Drinking behavior; Summer time; THI; Grazing dairy farms.	
Resumo: 	Grazing animals are exposed to heat stress and there should be conditions to facilitate water intake. Three experiments were carried out to determine the relationship between water intake, water temperature, and heat stress for Holstein pastured dairy cows. Experiment 1: Drinking behavior of 13 cows was evaluated (for 3 consecutive days) and four time periods were established according to the temperature humidity index (THI): (H1:05:00 to 10:59 h, H2:11:00 to 16:59 h, H3:17:00 to 22:59 h, and H4:23:00 to 04:59 h). The highest mean percentage of drinking bouts (53.2%) was registered in H2 (THI: 74.91 to 83.95). Drinking bout means among time periods were different (p &lt; 0.05), thus showing that heat stress conditions influence drinking behavior. Experiment 2: Three water troughs were placed in the sun (S) and three under a 2.2 m high structure covered with shade cloth (MS). Water temperature was registered at 10:00, 13:30, and 17:00 h, twice a week for 6 weeks. Mean water  temperatures at 17:00 h were 33.2 ± 1.6 ºC (S) and 25.3 ±.9 ºC (MS) and showed significant differences (p &lt; 0.05), thus supporting the shade cloth effect. Experiment 3: Five cows were offered water simultaneously at 18 and 31 ºC (T1 and T2), for 10 min, twice a day for 5 d. There were no significant differences among treatments (p &gt; 0.05). Recorded water intake in T1 (18 L ) was lower than in T2 (35.9 L ), although body heat dissipation was higher (T1 = 672.64 kJ d-1, T2 = 620.76 kJ d-1).	
Tipo: 	Journal article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000200017	
Editor: 	Instituto de Investigaciones Agropecuarias, INIA	
Formato: 	text/html	
Fonte: 	Chilean journal of agricultural research  v.70 n.2 2010