GI Disease in Herbivorous Rodents Flashcards
What is food selection in rabbits based on?
Food selection based on smell and vibrissae (long stiff hairs growing around the mouth or elsewhere on the face of many mammals, used as organs of touch; whiskers)
How are end products of digestion separated in rabbits GI?
- End products of digestion are separated in proximal colon –> large indigestible fibre particles rapidly eliminated as hard pellets –> smaller particles passed to caecum for fermentation
Where does microbial fermentation occur in rabbits?
What happens after this?
Microbial fermentation in caecum –> caecotrophs –> ingested directly from anus and subsequently digested in a similar manner to other monogastric animals
When are caecotrophs usually passed in rabbits?
Caecotrophs usually passed overnight or early morning -> covered in protective mucus
What are the following:
- Sacculus rotundus
- Fusus coli
- Sacculus rotundus at junction of small and large intestines
- Fusus coli is a 8-10cm, specially adapted area of the colon –> acts as differential pacemaker –> alters depending on phase of faecal excretion
What is colonic motility regulated by in rabbits?
What can stress do to rabbits?
- Colonic motility is regulated by the autonomic nervous system, prostaglandins and aldosterone
- Stress of any kind –> adrenaline –> inhibits gastrointestinal motility –> GI stasis
What kind of diets are reccomended for rabbits and herbivorous rodents?
- A diet high in fibre is essential
- Natural diet –> mixed grasses, shoots, leaves, roots & bark
- Chinchillas –> hold food in paws
- Guinea pigs –> vitamin C
- Selectively eat higher quality/calorific foods and prefer sweet- tasting foods
- Recommended diet for pet rabbits _ 80-90% grass/hay, 1-2 tablespoons pellets, variety of leafy greens (preferably weeds)
- Unable to vomit –> though do see clinically especially in guinea pigs and during anaesthesia
What are some causes of GI disease in Rabbits & Herbivorous Rodents?
- In short, virtually anything can cause gastrointestinal disease!
- Deficiencies in diet, husbandry and environment
- Secondary to other diseases, pain and stress
- Infectious organisms and toxins
What are some key points of the history of rabbits and herbivorous rabbits that you should check/ask?
- Fully review the husbandry diet and environment
- Hutch, house, free-range or combination
- Access to grazing
- Type and quantity of hay and how is it offered
- Mix or pellets and how much is offered
- Fresh produce offered and how much
- Treats e.g. Yoghurt drops, seed sticks, biscuits…
- Supplements, vitamin C (guinea pigs)
- What is actually eaten
What should you check on the clinical exam of rabbits and herbivorous rabbits that you should check/ask?
- Remember _ assess from afar 1st; good restraint!!
- May require stabilisation, analgesia/sedation first
- Thoroughly palpate and examine skull & mouth
- Auscultate chest and abdomem
- Palpate abdomen thoroughly but gently
- Check body condition, limbs and perineum
- Unkempt coat or ectoparasites may be due to obesity, orthopaedic or dental disease and/or inadequate husbandry –> may predispose to GI obstruction
What is ocular discharge usually due to in rabbits?
Ocular discharge is often due to molar disease. Chinchillas may often just wink
What is wrong with these 3 images?
- Faecal soiling
- Anal-rectal papilloma
- Matted fur on foot pads
What is the investigation for GI disease of rabbits and herbivorous rodents?
- Haematology and biochemistry
- Urinalysis
- Faecal flotation & wet smear
- Radiography
- Ultrasonography
- Endoscopy
- Oral exam and abdominal palpation under heavy sedation/general anaesthesia when stable
How useful is haematology and biochemistry when investigating GI disease in rabbits and herbivorous rodents?
Haematology and biochemistry often non-specific
- Commonly –> anaemia and stress leukogram
- Hyperglycaemia –> stress, pain, advanced liver disease.
- Hypoglycaemia –> starvation
- Elevated TP & HCT +/- urea/creatinine indicate dehydration
- Reduced albumin –> production/loss/ingestion
- Liver –> TBIL, ALT, AST, GGT, ALKP
- Urea –> circadian rhythm = higher in the evening
- Lead –> toxicity most commonly occurs after chewing old painted woodwork
What is this?
Rabbit faecal smear demonstrating bacteria, yeasts (Saccharomyces guttulatus) and coccidia (Eimeria steidae)
Is this rabbit normal or abnormal?
What is it?
Normal (rabbit) lateral abdominal radiograph
‘hard faeces phase’
Is this rabbit normal or abnormal?
What is it?
Normal (rabbit) lateral abdominal radiograph
‘soft faeces phase’
What is wrong with this rabbit?
Lateral (rabbit) radiograph:
cardiomegaly and hepatomegaly
What is wrong with this radiograph?
Gastric Bloat
distension may be due to varying degrees of gas or fluid accumulation
What is wrong here in this guinea pig?
Gastric torsion in a guinea pig; a relatively common presentation that is often missed!!
What is wrong with this chinchilla?
Moderate gastrointestinal stasis in a chinchilla with dental disease