Effect of sprinkling on feedlot microclimate and cattle behavior

Abstract

Experiments were conducted to evaluate strategies designed to reduce heat stress of cattle. In the first experiment, cattle were sprinkled for 20 min every 1.5 h between 1000 hours and 1750 hours (WET) versus not sprinkled (DRY). In a second experiment, treatments consisted of: (1) control, no water application; (2) water applied to the pen surfaces between 1000 hours and 1200 hours (AM); and (3) water applied to pen surfaces between 1400 hours and 1600 hours (PM). In both experiments, sprinkling lowered (P < 0.05) mid-afternoon temperatures. In the first experiment, relative humidity (RH) of WET versus DRY pens differed (P < 0.05) and averaged 72.4 and 68.9%, respectively. The average temperature-humidity index (THI) in WET pens was 0.5 units lower (P < 0.05), than the THI in DRY pens. In the second experiment, RH in sprinkled pens was also greater (P < 0.05) than RH in control (CON) pens However, THI differed (P < 0.05) among treatments, being 81.5, 80.9, and 80.3, respectively for CON, AM, and PM. Pens with sprinklers had a larger percentage of steers in areas where sprinkling took place, even on days when sprinkling had not occurred. Based on differences in percentage of cattle panting in sprinkled and non-sprinkled treatments, sprinkling was found to have a positive effect on cattle feeding area microclimate and to reduce the susceptibility of cattle to hyperthermia. However, cattle acclimatization to being sprinkled can result in slight hyperthermia even during cooler days when sprinkling would normally not be utilized.

Cow cooling on commercial drylot dairies: A description of 10 farms in California

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Cenários de mudanças climáticas e seus impactos na produção leiteira em estados nordestinos

“…Nos ambientes com condições muito estressantes para as vacas leiteiras confinadas, o uso de técnicas de climatização como, por exemplo, sistemas de resfriamento adiabático-evaporativo (SRAE), pode constituir-se em alternativa viável para mitigar o estresse animal por calor (Mader et al, 2007), especialmente para animais com elevados índices de produção. O SRAE permite aumentar o conforto térmico e melhorar a produção e qualidade do leite, principalmente quando dietas adequadas são formuladas para os animais durante os períodos mais quentes.…”

Impactos das mudanças climáticas na produção leiteira do estado de Pernambuco: análise para os cenários B2 e A2 do IPCC

“…Esse índice tem sido bastante utilizado em estudos de avaliação do conforto e/ou desconforto térmico animal (Mader et al, 2007), especialmente em análise de risco climático (Casa e Ravelo, 2003;Pires et al, 2006). Isto se deve ao fato do ITU requerer apenas dados de temperatura e umidade relativa (UR) do ar (Brown-Brandl et al, 2005), diferente de índices como o ITGU (Índice de temperatura do globo negro e umidade), que requer dados de temperatura do globo negro, os quais não são medidos em estações meteorológicas sinóticas.…”