Generally, the first indication that your dog has a digestive upset is deterioration in the faecal consistency. This is often followed by associated symptoms, such as lethargy, skin irritation and excessive thirst however, it is very rare for a dog to actually vomit.
In fact their stomach is able to cope with many challenges that would cause us severe problems, such as bacterial contamination with E coli, due to the exceptionally high acidity of its environment.
Digestive disorders generally occur lower down the tract in the intestines, and invariably are associated with a disturbance in the number and type of resident “friendly” bacteria present in the colon.
In some dogs relatively small changes in the composition or digestibility of their diet can elicit quite significant reactions. These responses are often termed sensitivities or intolerances, and can affect around 20% of the canine population in the UK.
For these dogs it is essential to provide highly digestible food with consistent recipes that are free from ingredients commonly associated with dietary intolerances, such as wheat, beef, soya and dairy products. An ideal diet would contain fish and white rice, which is gentle on digestion, has an excellent amino acid profile, and also provides omega-3 oils, which help to reduce inflammation in the digestive tract. It is also best to avoid red meats, such as beef and lamb, and the food should be fully cooked to maximise the digestibility of nutrients such as carbohydrate.
As well as bacterial disturbance anything that disrupts the natural rhythmic motion of the gut can also create digestive upset. In a healthy dog the normal peristaltic motion gently pumps the food through the intestines with a rhythm that allows the body time to digest and absorb the contents.
Conditions such as stress, anxiety, infection, excitement, and exercise can all disrupt this motion by causing erratic contractions, which generally result in poor digestion and faecal quality. Again, highly digestive food will provide the best opportunity for the body to cope with this, and portions should be small and frequent.
A moderate level of insoluble fibre, from ingredients such as beet pulp or pea, can also help to promote peristalsis by physically brushing the inside surface of the intestines, thereby stimulating it to return to its regular rhythm.
Any treats or snacks offered to a dog with sensitive digestion should also be low in fat since a high dose of fat can cause disruption of the gut bacteria as well as reduce peristalsis by lubricating the internal surface.