Anaemia in small animals

• General approach to anaemia

  Detailed history (including husbandry).

  Detailed clinical exam.

  Create a prioritised list of differentials.

  Discussion with owner.

  Diagnostic tests.

  Treatment plan.
• Taking history for anaemia

  Diet

  Faeces - quantity, appearance.

  Any recent changes

  Inside/outside.

  Stress? Pain?

  Any new pets?
• History taking for anaemia - diet

  Having the incorrect diet can predispose small mammals to lots fo different gastrointestinal disease.

  For example, incorrect diet can cause:

  • Bloat.
  • Diarrhea.
  • Microbial imbalance (dysbiosis).
  • Gastrointestinal bacterial infections.
  • Hepatic lipidosis.
  • Obesity which prevents caecotrophs ingestion.
• History taking for anaemia - environment

  Outdoor pets:

  • Exposure to wildlife e.g. virus and endoparasites.

  Indoor pets:

  • If loose, there is a higher chance of foreign bodies and trauma.
• History taking for anaemia - stress

  Stress causes hypomotility in hindgut fermenters which can then lead to anorexia and other problems such as gut stasis, gastric ulcers and bloat.

  Causes of stress:

  • Predators
  • New rabbits
  • Sudden change of diet.
  • Change of housing.
  • Transport.
  • Extremes of weather/temperature.
  • Loss of companion rabbit.
• Clinical examination of small mammals

  Similar to all species. Head to tail clinical examination.

  Main differences to a dog:

  • Auscultate the GIT in hind gut fermenters.
  • Dental examination methods (may differ between species e.g. guinea pig vs rat).
  • Checking things like ear canals and joints may not be part of evert exam in a dog, but they should be in a hind gut fermenter.
• Clinical exam differences in ferrets

  Similar to a cat, main differences:

  • Different handling techniques - scuffing is often used.
  • Splenomegaly is common and often an incidental finding.
• Clinical examination is small mammals

  Alway examine teeth during clinical exam and whenever anaesthetised for anything else.

  Observe and palpate whole head thoroughly.

  Retract lips to examine incisors (in rabbits and guinea pigs).

  In species with aradicalar hypsodont pre-molars and molars, always use an otoscope to examine molars, tongue, cheeks.

  Don’t forget to check eyes (nasolacrimal ducts pass tooth roots).

  Abdominal palpation, BCS, checking perineal area all very important.
• History taking for small animals - dental disease

  Reduced wear:

  • Not enough fibre (vegetation/hay).
  • Selective eating.

  Weaker teeth:

  • Sugary treats and fruit.
  • Vitamin C deficiency (guinea pigs).
  • Selenium deficiency
  • Ca/P imbalance (metabolic bone disease).
• Rabbit cheek teeth

  Like horses, lower cheek teeth only over grow into the tongue. And upper cheek teeth only overgrow into the cheek.

  An overgrowth is referred to as a spur.
• Guinea pig cheek teeth

  Guinea pigs are the same as rabbits. Only their lower cheek teeth curve slightly inwards this is normal. But it means when they overgrown they form an arch and trap the tongue.
• Ideal rabbit diet

  85% hay (not alfalfa).

  10% vegetables.

  5% pellets (not muesli).
• Breeding and dental disease

  Inherited predisposition.

  Malocculsion.

  Brachycephalic conformation.
• Clinical signs of gastro-intestinal disease in small mammals

  Anorexia

  Reduced/ no faecal output.

  Small dry faecal droppings

  Diarrhea.

  Hunched up/ lethargic.

  Faecal staining (+/- myiasis).

  Dribbling/ wet front paws.

  Caecotroph accumulation (rabbits).

  Anal impactions (guinea pig).
• Diagnostic tests in small mammals.

  Oral exam and abdominal palpation under sedation.

  Haematology and biochemistry.

  Urinalysis.

  Faecal flotation and wet smear.

  Radiography +/- barium

  Ultrasonography.

  Endoscopy
• Haematology and biochemistry in small mammals

  Often non-specific.

  Stress leukogram is a common finding.

  Hyperglycaemia from stress, pain or advanced liver disease.

  Hypoglycaemia from starvation/anorexia.

  Elevated Tp and HCT +/- urea/creatinine indicate hydration.

  Reduced albumin due to production/loss/ingestion.

  Liver parameters are TBIL, ALT, AST, GGT, ALKP.
• Common GIT conditions - hind gut fermenters

  Dental disease

  Gut stasis

  Bloat

  Gastric ulceration

  Impaction or foreign body.

  Neoplasia e.g. lymphoma, adenocarcinoma.

  Bacterial - dysbiosis and enteritis.

  Viral e.g. coronavirus, rotavirus, rabbit haemorrhagic disease (RHD).

  Parasitic e.g. pinworm, eimeria.

  Liver disease e.g. lipidosis.

  Liver lobe torsion (rabbits).

  Gastric dilation volvulus (guinea pig).
• problems in the small mammal - gut stasis

  Gut stasis is the slowing (or stopping) of the passage of food through the GI tract.

  Typically affects the hind gut in hindgut fermenters.

  It is a clinical sign rather than a diagnosis, but it needs to be specifically treated.
• Problems in the small mammal - gut stasis causes

  Pain.

  Stress.

  Incorrect diet

  Lack of caecotrophy.

  Gastrointestinal bacterial infection, viral, parasites.

  
• Problems in the small mammal - gastric bloat

  Two types of causes:

  • Physiological obstruction e.g. gastric stasis due to pain or diet.
  • Physical obstruction e.g. foreign body, neoplasia, GDV.

  
• Bacteria of hind gut fermenters

  Normal commensals = bacteroides, Enterococcus, Staphylococcus and E.coli.

  Bacteroides appear to inhibit pathogenic bacteria growth.

  Lactinobacillus are absent in rabbits.

  Enteritis (bacterial) clinical signs: anorexia, diarrhoea, haematochezia, dehydration, shock and death.
• What is dysbiosis?

  Microbial imbalance, usually overgrowth of clostridia and/or coliforms secondary to diet change, stress or oral antibiotics.
• GIT problems in small mammals - bacterial

  Bacterial enteritis:

  • Clostridia spp. overgrowth.
  • E.coli overgrowth in Juvenile rabbits under stress.
  • Salmonellosis
  • Pseudomonas
  • Yersinia pseudotuberculosis (acute from chronic forms).
  • Lawsonia intracellularis.
• What is dysautonomia?

  Idiopathic malfunction of the autonomic nervous system.
• Clinical signs of dysautonomia

  GI stasis.

  Dry mucous membranes and conjunctiva.

  Mydriasis

  Bradycardia

  Urine retention

  Megoesophagus

  Mucoid enteritis.

  Large intestine impaction.

  May be found dead with food impacted in mouth.
• GIT problems in hind gut fermenters - impaction

  Caecal impaction:

  • Occasionally occurs in adult rabbits.
  • Aetiology is often unclear, may be secondary to stress or ingestion of substances e.g. cat litter.

  Anal impactions:

  • Common in older male guinea pigs.
  • Gentle manual expression.
• Common GI conditions in ferrets

  Inflammatory bowel disease

  Endoparasites (e.g. ascarids).

  Protozoa (e.g. eimeria, giardia).

  Viral (e.g. ferret enteric coronavirus, rotavirus, canine distemper).

  Bacterial (e.g. Helicobacter mustelae, Lawsonia intracellularis, Salmonella, Campylobacter and E.coli).

  Obstruction (e.g. intestinal, anal glands).
• Common GI problems in ferrets - Helicobacter mustelae

  A lot of ferrets are carriers.

  Majority of ferrets do not have clinical disease.

  May increase the risk of gastric neoplasia, gastric ulceration and possibly liver disease.

  Can cause Megaoesophagus
• Common GI problems in ferrets - neoplasia

  Lymphoma and adenocarcinoma are common.

  Possibly secondary to Helicobacter mustelae.

  Often find enlarged lymph nodes on exploratory laparotomy (histology required).
• Common GIT conditions in rodents

  Enteritis:

  • Bacterial e.g. Salmonella, Clostridium piliforme (Tyzzer’s disease), Lawsonia intracellularis (wet tail).
  • Viral.
  • Parasitic e.g. oxyurids, cestodes.
  • Dietary change.

  Antibiotic associated enterotoxaemia.

  Cheek pouch impactions and infections.

  Overgrown incisors e.g. malocclusion, trauma.
• Staging acquired dental disease in small mammals

  Stage 1 = normal.

  Stage 2 = root elongation and deterioration.

  Stage 3 = acquired malocclusion

  Stage 4 = cessation of tooth growth.

  Stage 5(a) = end stage with osteomyelitis and abscess formation.

  5(b) = end stage with calcification of teeth and alveolar bone.
• Treatment goals for small mammals

  Restore circulatory volume (fluid therapy).

  Eliminate pain (analgesia).

  Restore gastrointestinal motility (prokinetics).

  Restore GI hydration (syringe feed q4 hours).

  Prevent ulceration and hepatic lipidosis.

  Eliminate stress (correct husbandry/handling).

  Identify and treat underlying diseases.
• Analgesia - doses for rabbits.

  Meloxicam (0.6mg/kg BID PO or SC).

  Tramadol (11mg/kg PO TID)

  Buprenorphine (0.01-0.05mg/kg SC or IM q4-8 hours).

  Maropitant (2mg/kg SC SID).

  Carprofen (2-4mg/kg SC or PO SID).

  Lidocaine CRI (100ug/kg/min
• Prokinetics - doses for rabbits

  Cisapride (acts on upper and lower GI) 0.1-1mg/kg q8-12 hours.

  Metoclopramide (upper GI only) 0.5-1mg/kg q6-12 hours.

  Ranitidine (mostly upper GI) 4-6mg/kg q8-12 hours

  • Only use these if there is no obstruction.

  Antacids: Ranitidine, omeprazole.
• Fluid therapy - doses for rabbits

  Subcutaenous fluids:

  • 10ml/kg, max 20ml per site
  • Isotonic saline, warmed.

  Intravenous (or IO):

  • Shock rate: 100ml/kg.
  • Maintenance: 4ml/kg/hr (can also divide into boluses.)
• Antibiotic treatment for small mammals

  Care when dispensing antibiotics to hind gut fermenters to avoid causing dysbiosis/enterotoxemia.

  Safe antibiotics include TMPS, metronidazole, enrofloxacin.
• Safe antibiotics for hind gut fermenters

  Safe (medications for treating small mammals):

  • Metronidazole
  • Fluoroquinolones (except pradoflocacin).
  • Tetracyclines
  • Sulfonamides
  • Macrolides (except erythromycin).

  Possibly dangerous:

  • Penicillins
  • Lincosamides (e.g. clindamycin).
  • Aminoglycosides (possibly).
  • Cephalosporins
  • Erythromycin
• Nursing small mammals - kenneling

  Keep away from busy areas as well as away from the sight, sound and smell of predators.

  Hospitalise with cage mate.

  Encourage owners to bring normal food and utensils.

  Ensure soft, dry bedding and plenty of fresh hay.

  Provide hide box.

  Gentle handling and restraint.
• Nursing small mammals - care

  Hand and syringe feeding.

  Cleaning soiling and discharges.

  Note faecal output (type, consistency and size).

  Gentle abdominal massage.

  Allow to exercise daily if condition allows.
• Nursing small mammals - nutritional support

  Hind gut fermenters, such as rabbits, need to eat regularly.

  When fasted their gut motility slows/stops and this can be fatal.

  We do not ever starve rabbits, even before anaesthesia.

  If a rabbit becomes anorexic, even just for a few hours, this needs to be addressed by providing nutritional support.

  Success of assisted feeding plans are dependant on the frequency of feedings, and what is being fed.