Reduced access to pasture linked to increased intake of grass

By: Horse Deals


Reduced access to pasture linked to increased intake of grass
Reduced access to pasture linked to increased intake of grass

Recent research by the Institute of Biological, Environmental and Rural Sciences(IBERS) about to be presented at a biannual nutrition meeting in the US suggests that ponies given reduced access to pasture are capable of ingesting considerable amounts of herbage during the time they are turned out and may indeed increase their intake during this time as they become accustomed to the routine.

Intake of large amounts of fructan, and other rapidly fermentable carbohydrates by grazing ponies has been linked to the development of laminitis and it has become common practice to restrict ponies’ access to pasture, especially at key times of the day/year in order to reduce the risk.

The study, which was conducted at the Institute of Biological, Environmental and Rural Sciences (IBERS), Aberystwyth University, in collaboration with the WALTHAM Equine Studies Group, aimed to investigate the effect of grazing restriction on herbage intake and grazing behaviour in ponies.

The grazing behaviour of eight ponies was measured daily over a six week period to assess their voluntary intake of herbage and to monitor the effects of restricting their access to pasture. Two groups of four pony mares were used. Group A had 24 hour access to pasture while the ponies in group B had three hours of pasture access per day and were stabled for the remaining 21 hours, with ad libitum access to haylage and water.

Herbage intake was estimated during the three hours when all the ponies were at pasture by monitoring the change in weight of each individual over the period. Grazing behaviour was analysed from video footage of the two groups using interval sampling. The ponies in group B had higher estimated grazed herbage intakes than those in group A during the three hours studied and this difference was significant during the final week, when they consumed 40% of their total daily dry matter intake as grass in the three hours at pasture. This compared with an intake of grass of around 25% of their daily dry matter ingested during the first week.

Clare Barfoot RNutr and the research and development manager at SPILLERS® said: "This suggests that ponies with reduced access to pasture are capable of ingesting considerable amounts of grass during the time they are turned out and may indeed progressively increase their intake during this time, indicating that the behaviour could be learned. The implication is that reducing ponies’ time out on normally managed pastures with the view to limiting the intake of rapidly fermentable carbohydrates may not be as effective as first thought."