The short-term effects of increasing meal frequency on stereotypic behaviour of stabled horses

In this study, we investigated the effect of increasing the number of meals of concentrate (whilst maintaining the same daily intake) on the behaviour of stabled horses with particular reference to stereotypic activities. The study was carried out on a working equestrian yard with stables for up to 50 horses. A pilot study was used to record incidence of stereotypic behaviour and to select subjects for the main study. In this, the behaviour of 30 warm-blooded horses was recorded during their morning (08:30 h) and afternoon (16:30 h) concentrate feeds. Whilst there was a low incidence of stereotypic behaviour (5.6% of scans) in the population, they were more commonly observed in the afternoon (7.1%) than the morning observations (4.2%; P < 0.05). The higher incidence in the afternoon observation appeared to be related to the lower availability of high fibre forage during the afternoon meal. In the main study nine horses were fed their normal ration of concentrate divided between two, four or six equally sized meals. Their behaviour was compared with seven control horses, which received two meals per day throughout the trial. As the number of meals increased, the treatment horses showed a decrease in oral stereotypies (P < 0.01), but an increase in weaving (P < 0.05) and nodding (P < 0.01) prior to feeding. The control group increased weaving, nodding and oral stereotypies (all P < 0.05) as their yard-mates received more meals. Consequently there was an overall increase in incidence of stereotypy in both treatment and control horses with the increase in meal frequency. The study, therefore, suggests that dividing the stabled horses’ concentrate ration into a number of smaller meals may be an effective means of reducing oral stereotypies, but that pre-feeding stereotypies may persist and that the practise may increase the frequency of stereotypic behaviour on unfed horses in visual contact.