Free Faecal Water (Ffw)

Horses suffering from FFW will commonly have messy hindlegs and tails caused by the excess water that is being expelled. In some cases this water can be produced entirely separately of any faces or defecation happening. Whilst this can look very unpleasant it can also cause irritation and soreness to the horses hind end and so will become a management issue.

There has been an increasing amount of research into FFW over the last decade, with many different factors investigated in relation to the development of the condition. Diet has anecdotally been associated, with wrapped forages such as haylage being suggested as a risk factor due to the higher moisture content. One study (Lindroth et al, 2018) found that of the majority of horses within the study displaying signs of FFW were those fed with wrapped forages (57%) but not when fed hay only. However, 20% of the horses in the survey did still show signs of FFW when being fed hay only. Contrary to popular opinion, 48% of horses with FFW did improve when turned out to pasture.

An additional study also looked at the effect of season and the likelihood of horses developing FFW (Kienzle et al, 2016). FFW has previously been associated with flushes of spring or autumn grass, and whilst this is known for disrupting the hindgut bacteria, the study found that 47.5% of cases were not related to season, with 47.5% of cases occurred only in winter months, and 9.5% showing signs of FFW when grazing spring pastures.

Interestingly, a further variable that the study found was that geldings had an increased association with the development of FFW. One hypothesis was that many of the horses suffering from FFW were at the lower end of the social hierarchy, and so consequently may suffer from social stress (Kienzle et al, 2016). This is a similar theory to that of the 'gut-brain' barrier, where anxiety and stress can lead to an increase in intestinal motility.

Finally, there has been evidence to suggest that inflammatory changes in the gut can also impact intestinal motility. Abnormal contractions in the large intestine may compress water out of digesta within the large intestines, causing an increase in 'free' water within the digestive tract that is not absorbed normally. This theory has also been confirmed in research comparing the dry matter content of 'normal' faeces with those with FFW (Ertelt and Gehlen, 2015).

Management Strategies

There are changes that you can make to your horses diet and management to help them overcome periods of FFW syndrome:

• Ensure your horse is receiving a balanced diet which utilises ingredients that support a healthy digestive system.
• Keep meal sizes small and reduce the starch content of your feeds if it is above 1g per 100kg of body weight per meal.
• Reduce stress where possible.
• Use forages with a high water holding capacity. Grass chaff has a better water holding capacity in the hindgut when compared to lucerne (alfalfa) or sugar beet.
• Review the forage portion of your horse’s diet - are they receiving enough? Ideally 2% of your horse’s body weight should be fed in forage per day unless they are on a calorie restricted diet where no less than 1.5% of body weight needs to be fed.
• Increase the dry matter (DM) content of your horses forage - If you are feeding a very wet forage i.e., haylage with a low DM content, gradually introduce a dryer forage such as hay or a haylage with a higher DM content.

Need more guidance?

If you would like any advice for your horse, please feel free to contact our nutritional team on 01622 718487 or fill out our Feed Advice Form.