Utfodring i finmaskiga hönät : hästens ättid och skötarens arbetsmiljö

Abstract: Horses are by nature herbivores, specialized on grass, and graze during the main part of the day. The horse has neither changed this basic behaviour nor the function of gastro-intestinal tract, when the horse was domesticated by man. A horse on pasture has an even production of saliva and gastric acids. The buffering effect of the saliva makes the pH in the stomach above four throughout most of the day. With abnormal long breaks of eating, the pH may decrease, causing an increased risk of gastric ulcer. Due to the physiological and psychological conditions of the horse there are benefits to design a feeding system similar to the natural way of the horse to distribute the time spent on feeding during the day. As the nutritional content in the forage nowadays is fairly high, free access of forage is unsuitable for many horses. A possible way to lengthen the feeding time is to hamper the availability of the roughage using a small-mesh hay-net. The study had two aims concerning feeding horses with small-mesh hay-nets, first if the system may increase the horse’s feeding time and second how the groom’s working routines are affected. The study had two main questions: How does feeding forage using a small-mesh hay-net affect the horse’s time spent on feed and the distribution of feeding time during the day. How does this feeding system affect working routines? It was hypothesized that the feeding time will increase with small-mesh hay-nets, and the working time is slightly changed. Two parallel studies were done at the Swedish National Equine Centre at Strömsholm. The first study focused on the feeding time and distribution using as a cross-over design where four horses were filmed during four days in each feeding system; feeding forage once a day in small-mesh hay-nets, with meshes sized 3x3 centimeters, and as control the same daily ration was given in four split-up portions. The study on working routines compared the two feeding systems using 14 horses fed with small-mesh hay-nets, and 17 horses fed with the forage ration split up in three portions. The working time was measured, and the working moments were observed and evaluated ergonomically, and valued by the students using a survey at the end of the experiment period. The average total eating time was significantly longer when using small-mesh hay-nets with an average increase of 38 % though individual variations were observed. For three out of the four horses in the experiment, the total feeding time per day were lengthened by 12-17 percentage points, whereas the eating time of the fourth did not change appreciable which probably depends on a decreased total consumption when fed in the small-mesh hay-net. When studying the distribution of eating time during the day one of the horses distinguished from the others by its feeding behaviour. It consumed the entire ration of forage immediately after being fed, which caused a break in feeding of 12-16 hours when fed once a day in the hay-net. The other horses distributed the eating evenly during the day in both systems. The working time used to feed the horses was significantly longer when using small-mesh hay-nets compared to the control group. Despite this, 69 % of the students preferred using the system with hay-nets. Due to the lengthened working time and material costs using small-mesh hay-nets in the system tested in this study is unprofitable compared to the system used in the control group. It was concluded that the feeding system with small-mesh hay-nets used in the study is not the optimal system for all horses. The long break in feeding shown by one of the horses may be unfavourable in a health perspective. The system with small-mesh hay-nets used in the study should be developed for ergonomically improvements, and rationalized to become less expensive. The hypothesis that the feeding time increased with small-mesh hay-nets was accepted, and the hypothesis that the working time is slightly changed was rejected.