Water spray cooling during handling of feedlot cattle

Abstract

Activities involved in receiving or working (e.g., sorting, dehorning, castration, weighing, implanting, etc.) of feedlot cattle cause an increase in body temperature. During hot weather the increased body temperature may disrupt normal behaviors including eating, which can be especially detrimental to the well-being and performance of the animals. Sprinkle cooling of animals has been successfully employed within the pen; however, added moisture to the pens' surface increases odor generation from the pen. A study was conducted to investigate the effectiveness of a single instance of wetting an animal within the working facility instead of in the pen, which could potentially provide extra evaporative cooling to offset the added heat produced by activity. Sixty-four cross-bred heifers were assigned to one of eight pens on the basis of weight. On four separate occasions during hot conditions (average temperature 28.2 ± 1.9°C, 29.1 ± 2.0°C, 28.9 ± 3.0°C, and 26.8 ± 1.6°C; with the temperature ranging from 22.6 to 32.5°C during the trials), the heifers were moved from their pens to and from the working facility (a building with a scale and squeeze chute located 160-200 m away). While in the squeeze chute, four of the pens of heifers were sprinkle cooled and the remaining four pens were worked as normal. The heifers that were treated had a body temperature that peaked sooner (31.9 ± 0.63 min compared to 37.6 ± 0.62) with a lower peak body temperature (39.55 ± 0.03°C compared to 39.74 ± 0.03°C), and recovered sooner (70.5 ± 2.4 min compared to 83.2 ± 2.4 min). The treated animals also had a lower panting score, a visual assessment of level of cattle heat stress (1.1 ± 0.2 compared to 1.16 ± 0.2). The behavior measurements that were taken did not indicate a change in behavior. It was concluded that while a single instance of wetting an animal within the working facility did not completely offset the increase in body temperature, it was beneficial to the animals without needing to add water to the pen surface, thus reducing the potential for odor generation.

Assessment of thermal load on transported goats administered with ascorbic acid during the hot-dry conditions

“…The values of AT and RH were markedly outside the reference thermo-neutral zone of 22-35°C for AT and 58-65% for RH, for goats in the tropical regions of the world (Zaytsev et al 1971;Richardson 2002). Similarly, the mean THI value of 87.8, which is an index of thermal load on animals, was above the normal comfort zone of 70-75 (Kadzere et al 2002;Brown-Brandl et al 2009). The result was similar to the findings of Darcan et al (2007), who showed that goats in hot-humid climate suffered heat-stress at AT of 29.2°C and RH of 86.2% (THI of 82.5).…”

“…Panting scores (ranging from 0-5) were recorded for the goats from each group before transportation, 15 min after loading, and during the transportation and post-transportation periods. The panting scores (Table 1) were recorded as earlier described in goats (Darcan et al 2007) and in cattle (Brown-Brandl et al 2009;Gaugban et al 2009). …”

“…Panting score (PS), rectal temperature (RT), heart rate (HR) and respiration rate (RR) have been shown to be good indicators of thermal stress, and may be used to assess the adverse effects of the thermal environment (Brown-Brandl et al 2009;Minka and Ayo 2010a). Cockram and Mitchell (1999), and Minka and Ayo (2010a) showed that as ambient temperature (AT) and RH or thermal load increase, the risk conditions for livestock in road transit change from safe (low AT, low RH), through alert, danger and finally to emergency situations, that is high AT and RH, which exceed thermoregulatory compensation mechanisms available to animals in transit.…”

Heat shock protein and gene regulation in goats during heat stress

“…Under the present study, the values of THI was observed under the mild and severe stage during whole experimental period causing heat stress to the goats and the elevated values of heat stress affects the thermoregulatory mechanisms (Kadzere et al 2002, Brown et al 2009. Amelioration of heat stress begins at the cellular level, where there is an interplay of various molecules including activation of heat shock transcription factor 1 that positively correlates to an increased expression of heat shock proteins by binding to promoter region of heat shock elements (HSE) of the HSP genes (Ruell et al 2009).…”

Welfare of beef cattle in Australian feedlots: a review of the risks and measures

“…Wetting cattle is another strategy that feedlot managers may employ to manage high heat loads. Studies utilising overhead water application for cooling feedlot cattle have predominantly focussed on reducing the impact of heat load on physiological responses such as increased body temperature, respiration rate and panting score (Davis et al 2003;Gaughan et al 2004aGaughan et al , 2008aBrown-Brandl et al 2010;Tresoldi et al 2018). Morrison et al (1973) found positive effects of sprinklers on feed intake and weight gain, but not feed efficiency in feedlot cattle.…”