Effect of high temperature on growth performance of calves maintained in outdoor hutches

Abstract

The aim of this work was to evaluate effects of high temperature on the growth, feed intake and health condition of calves kept in individual hutches in southern Slovakia. We tested a hypothesis that the calf performance would be infl uenced by the season at birth, sire lineage and gender. Sixtythree Holstein calves were reared in individual hutches from the second day of life to weaning at the age of 8 weeks. The calves originated from 5 sires. All calves were divided according to the temperature period at birth. The effects of period were determined according to two patterns: in pattern A, a low temperature period 1 (LT1, from April 4 to June 11, 69 days), high temperature period (HT, from June 12 to September 14, 95 days) and low temperature period 2 (from September 15 to November 24, 70 days) were distinguished; in pattern B, the results obtained in the LT1 and LT2 periods were combined and compared with those found in HT period. The same conditions of nutrition were ensured. We recorded 62 summer days and 14 tropical days during HT. Sixty-six days with the THI value above 72.0 and twenty-six with the values higher than 78.0 were found. The calves born during the HT had the lowest body weight from the fi rst week to the weaning in the both patterns (P<0.05). These calves drank up the most of water to the weaning, and had the least intake of starter mixture (P<0.05).

Pre- and postnatal heat stress abatement affects dairy calf thermoregulation and performance

“…Calves exposed to heat stress have a reduced ADG and weaning weight compared with calves provided active heat stress abatement or born in winter months (Hill et al, 2011;López et al, 2018). This is in part due to a decline in feed and nutrient intake and an increase in water intake (Beede and Collier, 1986;Broucek et al, 2008). In extreme cases, hyperthermia can lead to mortality .…”

“…Consequently, a significant number of calves might experience heat stress in both prenatal and postnatal environments. Many studies of postnatal calf heat stress do not take into account the prenatal exposure of the calf, so it is difficult to discern where performance responses originate (Broucek et al, 2008;Hill et al, 2011;López et al, 2018). This is relevant as recent literature demonstrates that prenatal stressors can profoundly affect fetal growth and organ develop-ment (i.e., microstructure and function) with long-term consequences on health and production (Berghänel et al, 2017;Van Eetvelde and Opsomer, 2017;Reynolds et al, 2019).…”

“…However, data are conflicting on the effect of postnatal heat stress on feed intake and BW gain. Calves born in summer in both temperate (Slovakia; Broucek et al, 2008) and tropical (Mexico; López et al, 2018) climates have reduced birth and weaning weight, ADG, and feed intake compared with those born in fall or winter, but it is unclear if these differences are due to pre-or postnatal heat stress exposure. A study during the summer in Ohio reported that individually housed calves cooled with a fan and shade had improved ADG and feed efficiency and reduced respiration rate when compared with calves housed identically but with no fans (Hill et al, 2011).…”

Seasonal, sex and live weight variations in feed and water consumptions of adult captive African Giant rats (Cricetomys gambianus, Waterhouse – 1840) kept individually in cages

“…Although photoperiod is the most important seasonal variable modulating circannual rhythms in temperate regions (Concannon et al., 2001; Morgan et al., 2003), ambient temperature ( T a ) and relative humidity (RH) appear to play a greater role in the tropics (Vathana et al., 2002). Therefore, the temperature‐humidity index or heat index (HI), which is a measure of thermal stress or comfort (Broucek et al., 2008), is particularly important in the tropics where animals are often under heat stress (Vathana et al., 2002). Feed and water consumptions can be measured with minimal disturbance of the animals (Valles et al., 2000).…”

“…They are among the physiological variables sensitive to stress (Marti et al., 1994) and are important in stress research because of their impact on growth and health (Valles et al., 2000). Heat stress affects performance of animals mainly as a result of deterioration in the appetite (Broucek et al., 2008). As the global temperatures rise, the impact on voluntary feed and water consumptions of animals is important for their survival, growth and production.…”