ABSTRACT
Slow feeding devices (SFDs) are useful tools in order to improve the horse well-being and to reduce wastage, but their use may result in unnatural posture during feeding and frustration behaviours. Moreover, it may be important to evaluate the laterality during feeding. The aim of the study was to investigate ponies' feeding behaviour (i.e., lateralisation, frustration, postural eating style) with different hay feeding methods: on the ground (G), a fully filled hay net (HF), a partially filled hay net (HL), and a slow feeder hay box (HB). Nine ponies of two different breed types (Shetland and Welsh/Cob) were evaluated. Video recordings were obtained and then behavioural analysis was conducted. Data were analysed statistically using k-means cluster analysis, repeated measurement mixed model procedure, principal component analysis (PCA) and Pearson's correlation coefficient. Head tilting was more often performed during feeding from HF and HL compared to G and HB. Forelimb forward, referring to the position that ponies assumed during feeding, was performed less frequently with the hay nets. Ponies, in particular Welsh/Cobs, tended to be more left-lateralized and performed more backward ears when feeding from the hay nets. Blink rate was observed to be greater when ponies were fed from G. No head pushing, striking with forelimb and pawing while feeding was seen. Animals fed from HF tended to eat from the top of the hay net and consequently showed an arched neck; while HL and HB showed for elongated neck an intermediate pattern between G and HF. From our results, HB seemed to be a useful compromise between natural feeding on the ground and the use of hay nets.
ABSTRACT
In the last decade, haynets and slow feeders have been promoted as sustainable tools to improve the feeding management of horses and reduce forage waste, but little is known about their effects on ponies. Therefore, the aim of this study was to analyze the effects of different hay feeding methods on the ingestive behaviors, intake rate and mouth shaping of ponies belonging to two breed types, which are characterized by different head morphologies. Shetland type (SH, n = 5) and Welsh/Cob type (WC, n = 4) ponies were fed hay using four feeding methods: on the ground (G), a fully filled haynet (HF), a partially filled haynet (HL), and a slow-feeder hay box (HB). Head morphology was measured for each pony. Video recordings were then made to apply geometric morphometrics and to perform behavioral analysis. The intake rate was measured for each pony and each feeding method. Data obtained with geometric morphometrics were analyzed using principal component analysis (PCA) and canonical variate analysis (CVA). Behavioral data and intake rate measurements were analyzed using a mixed model, a post-hoc Tukey's test, a Pearson's correlation test, and a stepwise regression model. The geometric morphometrics results demonstrated that feeding method influenced mouth shaping (36% for G, 78% for HB, 77% for HF, 83% for HL, considering the total variance of shape) and affected the intake rate. Differences in mouth shaping and ingestive behaviors in SH and WC ponies also confirmed the role of morphology in feeding management. The HL proved to be the most effective tool to increase feeding consumption time when needed (5 h/kg for SH ponies and 3 h/kg for WC ponies, considering the intake time), although the HB may be the optimal choice to reduce the intake rate while maintaining a more natural posture. Future studies are suggested to fully understand how body size and morphology influence feeding in equine species.
ABSTRACT
BACKGROUND: Horses are often fed high amounts of starch in their diets despite the well-established benefits of a fibre-based diet to promote gut health and animal welfare. The aim of the present study was to compare the effects of two different diets - one based on high amounts of starch (HS) vs. one base on high amounts of fibre (HF) - on specific parameters of the gut environment across different intestinal compartments of the horse digestive tract. To this end differences in the gastrointestinal environment between HS vs. HF fed horses were assessed in terms of dry matter, organic matter and ash content; the particle size distribution and volatile fatty acid composition were also investigated. RESULTS: Nineteen Bardigiano horses of 14.3 ± 0.7 months of age and destined to slaughter were divided into two group pens - one fed with high amounts of starch (HS; n = 9; 43% hay plus 57% starch-rich pelleted feed); vs. fed with high amounts of fibre (HF; n = 10; 70% hay plus 30% fibre-rich pelleted feed). Horses fed HS diet presented a higher dry matter content in the right dorsal colon. Moreover, they showed a higher organic matter and ash content in the sternal flexure, pelvic flexure, right dorsal colon and rectum. In these latter intestinal compartments, horses fed a HS diet also showed a higher proportion of particles retained on an 8 mm sieve and a higher proportion of particles that washed through the finest sieve (< 1 mm). Moreover, the total amounts of volatile fatty acids as well as valeric acid were found to be significantly higher in horses fed the HS vs. HF diet. CONCLUSIONS: A high-starch diet causes significant changes in the horse gut environment. We observed an increase in the dry matter content in the right dorsal colon, as well as reduced particle sizes and an increase in the production of valeric acid in all the gut compartments studied. High-starch diets should be avoided in favour of fibre-based diets with the goal of safeguarding gut health in horses.
