Comparison of stable environment in prior approved and non-prior approved horse stables

Abstract: To establish good horse welfare there are several factors that need to be considered. One important factor is the environment in which the horses are kept. In Sweden horses are stabled during long periods of time in the cold season and consequently the stable environment is even more important. The most essential environmental factors in a horse stable are ambient temperature, relative humidity (RH) and concentrations of contaminants in the stable air. The air in a horse stable contains dust, noxious gases, moulds and microorganisms which all can contribute to developing respiratory diseases in horses. In Sweden it is legislated that when a livestock building is erected, altered or extended it needs a prior approval from the County Administrative Board. The aim with the legislation is to approve the building from an animal welfare and animal health perspective and to prevent welfare issues. The aim of this study was to compare stable environment in stables with prior approval with stables without in order to investigate whether the prior approval process has a positive effect on stable environment in horse stables. Temperature, RH, carbon dioxide (CO2) and ammonia (NH3) were measured in four horse stables; two with prior approval and two without. The measurements were conducted in the morning at feeding in the stable and outside at three consecutive days. In addition, data loggers were placed in the stables and outside for continuous measurements of temperature and RH during the same three consecutive days. The results from the study show that the prior approved stables have higher values of CO2 and NH3. However, those values were far below the legislated maximum limits in Sweden. From the collected data from the data loggers there were many values of RH that had to be removed because they were not reliable. Overall high values of RH could be seen in all four stables and no major differences between stables could be seen. On the basis of these results, the conclusion of this study is that the prior approval process is no guarantee for a good stable climate and air quality. However, it is not possible to determine whether prior approved stables have better stable environment than non-prior approved stables in general because of the differences in ventilation system, stable size, bedding material and feed in the studied stables as well as the small number of stables studied. The results of this study give an indication that this issue is of importance and needs to be researched further to achieve adequate long term horse welfare in Sweden.