Behavioural, biochemical and hormonal responses of heat-stressed crossbred calves to different shade materials

Abstract

An attempt was made to study the effect of different shade materials on physiological, behavioural, biochemical and hormonal responses in crossbred Vrindavani calves during the summer seasons in the Cattle and Buffalo Farm of Indian veterinary Research Institute, Izatnagar, India. During experiment, 28 crossbred calves were divided into four groups: thatch shading roof (T1), agro-net shading roof -60% light diffusion (T2), asbestos with canvas shading roof (T3) and well-grown tree (T4). The daily macroand microclimate data were recorded at 0900 and 1400 h. The data for each ongoing behavioural activity were recorded by closed circuit television consecutively for three days for each animal in each group from 1000 to 1700 h. Blood was also collected at 0, 15, 30, 45, 60, 75 and 90 days of the experimental period for estimation of different biochemical parameters. The microclimate, that is, maximum and minimum temperatures, relative humidity and temperature humidity index of the roof, was lower in the T2 group. There was significantly more (P < .05) time spent in shade structure by the T2 group as compared to other groups. Among the behaviour, feeding, rumination, resting and sleeping activities were more in the T2 group, whereas standing, moving, drinking, time spent near water tank and abnormal behaviour (cross-sucking, licking) were more in T3 and T4. Among the blood parameters, haemoglobin was significantly higher (P < .05) while, Serum Glutamic Oxaloacetic Transaminase and Alkaline Phosphatase were significantly lower in the T2 group. ARTICLE HISTORY

Resilient capacity of cattle to environmental challenges – An updated review

“…One of the profound behavioral responses the animal exhibit during heat stress is shade-seeking behavior. Placing a simple shade over the animal exposed to direct solar radiation may reduce the heat load of about 45% (Kamal et al 2016). Shade seeking behavior is an attempt of the animal to ameliorate the direct negative effects of heat load during heat stress exposure.…”

“…Heat-stressed animal spend more time in standing posture in order to reorient themselves in different directions to avoid direct solar radiation and ground radiation. During thermal stress, animal upsurge evaporative heat loss in order to reduce the excess heat load from the body surface and assist in convection by standing more time to get away by the conductive and radiative heat from the surroundings (Kamal et al 2016;Sejian et al 2018). Even mild heat stress also result in increased standing time which may lead to lameness in cattle, when the animal stands for more than 45% per day (Tucker et al 2008).…”

Parámetros bioquímicos y hematológicos en ovinos de pelo con y sin sombra bajo condiciones desérticas

“…Bajo condiciones de clima cálido, las concentraciones de los parámetros hematológicos en animales se modican. La mayor concentración de Hb en el tratamiento sin sombra puede estar asociado a mecanismo de adaptación de las corderas para proporcionar la cantidad necesaria de agua hacia el sistema circulatorio, para enfriarse por evaporación (Kamal et al 2016). Además, las corderas en este tratamiento evidenciaron que hubo condiciones de estrés por el incremento en los niveles de Hb en la sangre, como consecuencia de mayor demanda de oxígeno, para activar los mecanismossiológicos de termorregulación (Ribeiro et al 2014, Al-Dawood 2017.…”

“…Las variaciones de la cantidad de sangre circulantes en el organismo y la tasa a la cual ésta se evapora de la piel y del tracto respiratorio están relacionadas con el incremento del consumo de agua (Richards 1973). Estas modicaciones en la cantidad de sangre circulante en el organismo pueden resultar en alteraciones de parámetros hematológicos, bioquímicos y hormonales debido a que la sangre es un indicador importante del estrés calórico en animales (Sullivan et al 2011, Kamal et al 2016. Además, la sangre es altamente sensible a los cambios ambientales, por lo que cualquier cambio cuantitativo y morfológico en las células sanguíneas se vincula de forma directa con el estado siológico o patológico del animal (Bhan et al 2012).…”

Physiological and rumen microbial responses of Angus cattle (Bos taurus) following exposure to heat load

“…All animals have mechanisms to respond to any adverse environmental condition that change homeostatic balance. Cattle can respond physiologically (Ames & Ray 1983;Hahn & Nienaber 1993;Hahn & Mader 1997), behaviourally (Castaneda et al 2004;Brown-Brandl et al 2006b;Kamal et al 2016), and metabolically (Gaughan et al 2010b; to minimise the effect of the heat stress. All these responses depend on the quantum and duration of the excessive heat load gained (Ames & Ray 1983;Hahn & Nienaber 1993;Hahn & Mader 1997).…”