Evaluation of covering materials in individual shelters and its effects on physiological responses and performance of dairy calves

Abstract

ABSTRACT:In Tropical regions, the animal performance is often affected by climate conditions. This study aimed to evaluate covering materials in individual shelters, normally used to house dairy calves, and its influence on the calves physiology and performance. The design used was completely randomized, with a 2x3 factorial arrangement to compare the averages of 5% through the Tukey's test, i.e., both genders-and three types of covering in the shelters (Z -zinc; ACasbestos cement; and WPAC -white-painted asbestos cement). Parameters evaluated included daily weight gain (DWG), dry matter intake (DMI), feed conversion (FC), rectal temperature (RT), and respiratory frequency (RF). Results showed significant differences (P < 0.05) among males (1.04kg/day) and females (0.74kg/day) for DWG and interaction between gender and treatment (P < 0.05) for zinc covering (0.562kg/day for females and 1.120kg/day for males). Significant differences were also observed in FI of animals housed under shelters with the covering of zinc (48.35kgDM/day for females and 96.91 kgDM/day for males). There were no significant differences (P > 0.05) in the FC and the RT, and there were significant differences (P < 0.05) for RF in the Z treatments (56.9 mov.min -1 ), WPAC (62.2 mov.min -1 ) and FC (70.25 mov.min -1 ). It was concluded that different covering materials did not affect performance and dry matter intake of dairy calves. However, the animals' physiology of thermoregulation was altered by the different covering materials used in individual shelters. KEYWORDS: thermoregulation, weight gain, feed conversion. AVALIAÇÃO DE MATERIAIS DE COBERTURA EM ABRIGOS INDIVIDUAIS SOBRE RESPOSTAS FISIOLÓGICAS E DESEMPENHO DE BEZERROS LEITEIROSRESUMO: Nos trópicos, o desempenho animal é prejudicado pela ação do clima. Objetivou-se neste trabalho avaliar materiais de cobertura em abrigos individuais sobre a fisiologia e o desempenho de bezerros leiteiros. Utilizou-se o delineamento inteiramente casualizado, fatorial 2 X 3, para a comparação das médias ao nível de 5%, pelo teste de Tukey, ou seja, dois sexos e três tipos de coberturas (Z -zinco; CA -cimento-amianto e CAB -cimento-amianto pintado de branco). Foram medidos o ganho de peso diário (GPD), o consumo alimentar (CMS), a conversão alimentar (CA), a temperatura retal (TR) e a frequência respiratória (FR). Os resultados mostraram que houve diferença significativa (P < 0,05) entre machos (1,04 kg/dia) e fêmeas (0,74 kg/dia) para GPD, interação sexo e tratamento (P < 0,05) para a de cobertura de zinco (0,562 kg/dia para fêmeas e 1,120 kg/dia para machos), e o CMS apresentou diferença significativa para cobertura de zinco (48,35 kgMS/dia para fêmeas e 96,91 kgMS/dia para machos). Não houve diferença significativa (P > 0,05) para CA e TR e observou-se diferença significativa (P < 0,05) para FR nos tratamentos Z (56,9 mov.min -1 ), CAB (62,2 mov.min -1 ) e CA (70,25 mov.min -1 ). Conclui-se que os diferentes tipos de coberturas não influenciaram no desempenho e no consumo alimentar, mas interferiram ...

Conforto térmico e desempenho de bezerras Girolando alojadas em abrigos individuais com diferentes coberturas

“…Do mesmo modo, Fonseca et al (2012) afirmam que os animais mantidos sob cobertura de zinco estiveram em estágio de baixo estresse e justificam que isto pode ter ocorrido devido à diferença no balanço de radiação de ondas longas em relação aos demais materiais e à alta capacidade que o zinco tem de reflexão e dissipação do calor.…”

“…Não houve diferença significativa (p > 0,05) para a variável GP das bezerras (Tabela 2), o que reforça os resultados apontados por Fonseca et al (2012) que não observaram comprometimento no desempenho dos animais em relação aos manejos de cobertura avaliados, cimento amianto pintada de branco, zinco galvanizado e cimento amianto.…”

Invited review: Influence of climatic conditions on the development, performance, and health of calves

“…Macaulay et al (1995) compared 3 housing types during fall and found that enclosed molded polyethylene domes had the warmest microclimate, followed by conventional wooden hutches and thermomolded opaque polymer hutches. Roof material seemed to have only a minor influence on the thermal comfort of calves (Kawabata et al, 2005;Fonseca et al, 2012).…”

Thermal Efficiency of Different Coverage Materials in Reduced Models of Animal Husbandry Facilities: A Case Study

“…Relative humidity values above 60% reduce heat transmission from the inner part of the body to the periphery, which hinders the thermal changes with the environment (LIN et al, 2005;ABDELQADER & AL-FATAFTAH, 2014). FONSECA et al (2012) concluded that individual shelters with different coverage types had no influence on dairy calf performance. However, these authors observed a significant difference in the animal respiratory rate, with the lowest value observed in treatments with zinc tiles (56.9 mov min −1 ) and the highest value was observed in the treatment with fiber-cement tiles without white paint (70.25 mov min −1 ).…”