Caecotroph disorders in rabbits
Caecotrophy is an entirely normal and essential behaviour in rabbits which consists of eating soft, mucus covered faeces known as caecotrophs. The formation of these nutritionally rich packets of waste starts in the caecum. For the rabbit they are an important source of amino acids, volatile fatty acids, vitamins, and enzymes. Unfortunately, there are several conditions that interfere with the formation and intake of caecotrophs which can cause some significant problems.
How do they form?
Rabbits are strict fibrevores, always requiring a fibre rich diet. Whilst the digestion in the stomach and small intestine is more like a monogastric species, the large intestine is entirely involved in the processing of non-digestible fibre. This fibre is separated in the proximal colon into coarse and fine fibre particles, with the coarse undigested fibres being moved distally and the small fibre particles being moved back towards the caecum.
- Large undigested fibres – these are excreted in dry, hard fibrous faeces. This is the ‘crude fibre’ listed in the analytical constituents on products
- Small digestible fibres- these undergo bacterial fermentation, which allows for the synthesis of amino acids, volatile fatty acids, and water-soluble vitamins that make up the caecotrophs .
At Burgess we also measure ‘beneficial fibre’in the analytical constituents which is a combination of both types of fibre.
Some of the nutrients formed from fermentation are absorbed through the wall of the caecum, whilst the rest form a soft pasty material rich in bacteria, amino acids, vitamins, enzymes, minerals, and volatile fatty acids.
The pasty content of the caecum is then moved rapidly through the colon without any separation of liquid and solid parts, to be finally excreted as caecotrophs. This movement is controlled by the autonomic nervous system acting on the fusus coli, a highly vascular and innervated section of the ascending colon. Hormones such as aldosterone and prostaglandins are also involved. In the fusus coli, contents are pressed and divided into small portions which are then covered with mucus before being excreted as caecotrophs.
The formation of caecotrophs follows a circadian rhythm, with most being excreted during the morning and evening. Many owners are initially surprised to discover that caecotrophs are ingested directly from the anus! Here are some interesting facts about caecotrophy.
- A healthy diet – a diet high in benefical fibre will usually result in all caecotrophs being eaten. Healthy rabbits eating large amounts of fibre eat all their caecotrophs.
- Clumps of caecotrophs – if these are discovered, they should act as a warning sign that something is wrong.
- Restricted food – this would normally result in all the caecotrophs being eaten.
- Low fibre high protein diet – this will result in less efficient caecotrophy. Unhealthy rabbits eating low-fibre foods tend to ingest only part of them.
- Smell and consistency - the type of food can affect the nature of the caecotrophs, making them less appealing to the rabbit.
Many factors can alter caecotrophy, including illnesses, diseases, diet, body condition and stress. This tends to occur because of an alteration in the consistency of the caecotroph itself, or perhaps restricting the ability to ingest from the anus. Ultimately, if a rabbit fails to eat enough caecotrophs, it will eventually become deficient in essential vitamins and amino acids.
The consistency plays an important role in whether the rabbit is keen to eat them. They should have a texture that is soft yet firm, and a shape that is easy to prehend, crush and swallow. They also need to be covered in a protective mucous lining. Most rabbits will avoid overly pasty caecotrophs.
In most healthy animals, almost the entire volume and quantity of caecotrophs produced is eaten. In abnormal conditions or ill health, caecotrophs will gather in the corner of the housing, bedding or under the tail, and unfortunately, many owners fail to notice this in time. Occasionally we might be presented with an animal that has been caecotroph deficient for weeks or months. Below are 11 examples of where the normal process of caecotroph production and ingestion can be altered.
- Poor nutrition – low fibre diets will inevitably reduce gut motility in the rabbit. As has already been described, normal caecotroph formation relies on adequate levels of dietary fibre. Muesli style diets may also result in inadequate caecotroph consistency and value.
- Change of diet – the introduction of new foods rich in water produces changes in the consistency of soft faeces. This in turn will alter the gut microflora and the digestive transit time, resulting in abnormal caecotroph production.
- Inappropriate handling – the effects of stress from poor handling by inexperienced owners can have a profound effect on gut motility and caecotroph formation.
- Pain - any health condition that results in pain is likely to cause a problem with caecotroph production. This usually occurs because pain often decreases appetite and may also restrict the animal’s ability to reach round to its anus.
- Dental disease – malocclusion can make it difficult for the rabbit to eat sufficient fibre from grass and hay to sustain normal gut activity.
- Skin and urinary tract disease – any condition that influences the healthy skin surrounding the perineum will result in pain and infection from a secondary dermatitis. These animals need to have the urinary, skin, and gastrointestinal systems improved.
- Predators – the stress and fear that can be incited by the presence of noisy dogs, children and other potential predators will inevitably reduce caecotroph production.
- Obesity – any rabbit which is significantly overweight or obese will find it difficult to self-groom. This is because of the abdominal and dewlap fat obstructing the ability for the rabbit to reach the anus to ingest the caecotroph.
- Breeds – some rabbits will produce long fine hair which becomes very hard to groom and keep clean. Caecotrophs can stick to the hair making them hard to ingest.
- Diarrhoea - in the case of a rabbit with diarrhoea, this can rapidly become serious through loss of electrolytes and dehydration. As you would expect, a gastrointestinal tract which is overactive is unlikely to produce normal hard faecal pellets or caecotrophs.
- Elizabethan collar – be aware that by attaching and using a protective collar, you may stop the rabbit from being able to eat the caecotrophs.
Caecotroph perfection with Burgess Excel Long Stem Feeding Hay
At Burgess Pet Care we produce a range of high quality feeding hays for rabbits, providing the essential beneficial fibre they need. This includes Burgess Excel Long Stem Feeding Hay which is the ideal product to stock in your clinic. You’ll be assured that you are only offering the very best quality food.
7 Key benefits of Excel Long Stem Feeding Hay
- High in beneficial fibre – all fibrevores need a reliable source of good quality digestible and indigestible fibre. Timothy grass hay provides this.
- Low in sugar – we need to avoid feeding high carbohydrate and sugars to hind gut fermenters.
- Dust Extracted – to support respiratory health.
- Controlled Drying – by air-drying the hay and monitoring the moisture levels, we prevent the hay being stored and packed with a moisture content that is either too high or low. This reduces the risk of mold spores from forming and so minimises the risk of allergic or fungal diseases, not to mention mycotoxicosis.
- Palatable – the hay is cut at full bloom before it becomes too old and woody. This ensures a fresh, fragrant, green product that retains a very high palatability.
- Nutritional content – we l declare the nutrient analysis , so you’re assured of the quality of what is being offered.
- Quality controls – our fields are monitored for unwanted weeds such as ragwort and we carry out other quality checks throughout the harvesting and packing process.