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Botto Ľ., Lendelová J., Strmeňová A., Reichstädterová T., 2014. The effect of evaporative cooling on climatic parameters in a stable for sows. Res. Agr. Eng., 60 (Special Issue): S85-S91.The aim of this study was to find out the effect of indirect evaporative cooling on microclimatic parameters in a stable for sows. A high-pressure system was used for cooling, the nozzles sprayed water into the outside air before its entering into the building. Temperature-humidity index during cooling was higher by 0.9 than in the section without cooling (P < 0.001). Due to low indoor air flow velocity (below 0.18 m/s), a change in apparent temperature by the Comprehensive Climate Index (CCI) was only 1.94°C. It would be possible to provide markedly better cooling effectiveness by increasing the air velocity up to 2 m/s, which may improve the CCI by 19.8% and thus to achieve better environmental conditions for housed sows. The efficiency of evaluated evaporative cooling system was moderate because the nozzles were placed outdoors and only part of humidified and cooled air was drawn into the building through inlet openings, and also because the indoor air-flow velocity was low.Keywords: cooling system; water evaporation; summer period; pigs Current modern types of pigs are demanding as to conditions of stable environment. Pigs are relatively sensitive to high environmental temperatures when compared to other species of farm animals. A lot of research has been done on the factors affecting heat production in pigs (Brown-Brandl et al. 2001). Air temperature as cardinal environmental factor is influenced by relative humidity and air flow velocity. Optimum parameters of temperatures, relative humidity and air velocity for pigs in Slovakia were presented by Botto et al. (1995). Recommended optimum of the air temperature for pregnant sows is 12-20°C at relative humidity 50-75%. Max. air flow velocity at optimum temperature is 0.3 m/s and at temperature higher than optimum it is 2.0 m/s.Heat waves during summer cause large losses in productivity in animal husbandry. Sows are exposed to heat stress when temperature exceeds the upper critical temperature of the thermoneutral zone of the sow (Black et al. 1993). Thermoneutral zone is the range of environmental temperatures within which the metabolic rate is minimum and independent of temperature. The temperatures that bound this zone are known as upper and lower critical temperatures (Webster 1991). Above the upper critical temperature of this zone the animal will reduce both production and reproduction to control body temperature. Sows begin to feel the negative effects of heat stress at a temperature of 20°C, and temperatures of 26°C and higher are

The aim of this study was to investigate the changes of lying time and other behaviour manifestations of dairy cows during usage of different cooling systems of animals. Alternative hypothesis was presumption, that the lying time of cows in lying cubicles with applied two different cooling systems are indifferent. The sprinkling system was used to animal cooling in group S in summer time. In group SV was disposable sprinkling system and diagonally rotated ventilators. Activities and the rest of animals were evaluated in 10 minute intervals using a camera system for 24 hours. Data obtained was tested by nonparametric Kruskal-Wallis one-way ANOVA and multiple comparison test for detecting of significant differences in the behaviors between groups of cows. There was found positive effect of animal enhanced cooling using sprinkling system with increased air movement by ventilators. It reflected in significant prolongation of whole lying time and shortening of time, when animals were standing. It resulted from final values of investigated behaviour manifestations of dairy cattle within 24 hour period that animals in group SV with sprinklers and ventilators lay in stalls longer than in group S with sprinklers, but without ventilators (10.76 h*d -1

AbstractThe purpose of this study was to theoretically and practically investigate the thermo-technical properties of two bedding surface materials under real farm conditions during the hot summer period. The study was focused on the research of cubicles with water mattresses and straw bedding for dairy cows. The results of thermal-technical calculations showed that straw belongs to the category of warm floors, the thermal effusivity value of cubicle with straw is b = 173.55 W·s1/2·m−2·K−1; the heat transfer coefficient is U = 0.36 W·m−2·K−1. Water mattress belongs to the category of cold floors with the thermal effusivity value b = 572.46 W·s1/2·m−2·K−1 and the heat transfer coefficient U = 4.504 W·m−2·K−1. On the basis of calculations, the results showed that U was 12.5 higher for water mattresses than for straw, and b was 3.3 times higher for water mattresses than for straw. Based on thermographic measurements under field conditions of dairy farm, it was observed that the surface temperature of the water mattresses after one hour of lying was lower by 4.95 ±1.88 °C in comparison to chopped straw. In practice, suitability of the material structure of water mattresses was verified on the basis of physical properties for summer period.

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