Exotics 2 - Aimee Flashcards
What are the features of metabolic bone disease?
- Rickets
- Osteomalacia
- Fibrous osteodystrophy
Describe the etiology of MBD
Multifactorial
- Absolute calcium deficiency
- Ca:P imbalance
- Vitamin D deficiency
What is rickets?
Inadequate mineralization of bone due to deficiencies in vitamin D and or calcium
What is osteomalacia?
Softening of bone due to mineral loss from a previously mineralized bone.
Which age group is usually affected by osteomalacia?
Adults
What is fibrous osteodystrophy?
Replacement of bone with fibrous material.
Fibrous osteodystrophy is a common feature of which disease and which condition?
Metabolic bone disease
Nutritional secondary hyperparathyroidism (condition)
How is vitamin D metabolized?
- Sunlight exposure is absorbed by the skin.
- The skin synthesizes vitamin D3 (cholecalciferol).
- Vitamin D3 is processed in the liver to calcidiol.
- The kidney transforms the calcidiol into calcitriol which is the active form of vitamin D3.
What are the target organs of vitamin D?
- Intestines: Enhances calcium and phosphate absorption.
- Bone: Promotes bone mineralization.
- Parathyroid glands: Regulates parathyroid hormone production.
Which form of vitamin D is required by new world primates, birds, reptiles, and fish require?
D3, they cannot use D2.
Which species are unable to ingest adequate vitamin D through their diet?
Most reptiles cannot and require adequate sunlight/UVB exposure.
What form of vitamin D is used by mammals?
Most mammals can use D2 and D3
What are common clinical signs of metabolic bone disease (MBD) in young animals?
- Lameness
- Bone deformities
- Fractures and softening of bone
- Swollen jaws and tooth loss
- Hypocalcemic tetany
What additional signs of MBD are specific to reptiles?
Signs in reptiles include deformed shells (in turtles) and paralysis (especially in lizards).
What additional signs of MBD are specific to birds?
Signs in birds include poor feathering and deformed/soft eggs.
What additional signs of MBD are specific to primates?
Reluctance to climb.
In which animal groups is MBD most common?
MBD is most common in young carnivores, birds, and reptiles.
What caution should be taken during a physical exam of an animal with severe MBD?
In severe cases of MBD, the jaw can fracture during a physical exam if the mouth is opened with significant force.
What are some clinical signs of metabolic bone disease (MBD) in animals that can lead to diagnosis?
Facial and long bone swelling, especially in primates and carnivores. Osteodystrophy.
What can diagnostic imaging reveal in cases of MBD?
Radiographs showing reduced bone density and cortical thinning.
What blood tests are relevant for diagnosing MBD?
Total serum calcium levels, ionized calcium, and plasma vitamin D levels (may be extremely low).
What may happen in severe cases of MBD regarding X-ray visibility?
Long bones and pelvis may not be visible on X-ray, which could lead to consideration of euthanasia.
How is MBD diagnosed?
- History and physical exam
- Diagnostic imaging
- Bloodwork
Describe vitamin D requirements in birds.
No dietary requirement if they receive adequate sunlight.
Their uropygial gland contains vitamin D3 precursors that are activated by the sun.
How is MBD treated (acute)?
Calcium gluconate is given IV if the animal is having seizures.
How is MBD treated (chronic)?
- Ca:P supplementation at proper ratio in diet (1.5-2:1)
- Vitamin D supplementation if not getting UVB light/sunlight
What is the proper Ca:P ratio in diet?
1.5-2:1
Avoid injectable vitamin D products that contain high….
Vitamin A
How is MBD prevented?
- Feed balanced diets with known nutritional profiles
- Allow access to unfiltered sunlight / full spectrum light (or at minimum UVB light)
- Keep reptiles in their POT(H)Z - preferred optimal temperature and humidity zones
What diets are deficient in calcium?
- Seeds
- Muscle/organ meat
- Fruit
- Most grains
- Most insects
What UVB wavelength should be used?
290-315nm
What should be considered with full spectrum/UVB bulbs?
- Expiration dates
- Distance from animals
- Basking areas
- Mesh wire (reduces some light)
- Plastic vs glass terrariums
Measure in cage with UV reader
What is the result of UVB/full spectrum light in reptiles?
Improves Ca uptake in GIT
What is vitamin A required for?
- Cell replication
- Vision
- Bone remodelling
- Epithelium integrity
- Immune function
- Reproduction
What diets are deficient in vitamin A?
All meat and all seed diets.
What are the clinical signs of hypovitaminosis A in birds?
- White plaques in mouth and esophagus
- Blunting of choanal papillae
- Conjunctivitis, sinusitis, resp infections
- Poor growth
- Ataxia
- Gout
- Occlusion of uropygial gland
- Abnormal feathers
- Squamous metaplasia of the salivary glands (parrots)
What species of bird is especially prone to hypovitaminosis A?
Parrots
What are the clinical signs of hypovitaminosis A in amphibians?
- Short tongue syndrome (result of plugged mucus glands)
- Lethargy
- Weight loss
- Conjunctival swelling
- Dermal and bone lesions
What are the clinical signs of hypovitaminosis A in rabbits?
- Hydrocephalus in neonatal rabbits
- Stillbirths
What are the clinical signs of hypovitaminosis A in all species?
- Poor fertility and growth rates
- Blindness (malfunctioning rods)
How is hypovitaminosis A treated?
- Vitamin A injection
- Dietary correction (animal liver, dark leafy greens, fortified pellets)
What can result from vitamin A injection?
Hypervitaminosis A if too much is given.
What species gets adequate vit A in diet?
Tortoises
How is hypovitaminosis A prevented?
Ensure diet has adequate levels of retinol
What species requires vitamin A precursors?
Herbivores
Beta carotene and other carotenoids
What is the function of vitamin E / selenium?
- Selenium and Vitamin E reduce free radical damage
- Important for reproductive, muscular, circulatory, nervous and immune functions
Which species are most affected by vitamin E / selenium deficiency?
It is the most common nutritional disease of captive ruminants. Also a problem in free-ranging wildlife due to low levels in soil in some areas.
- Guinea pigs
- Hamsters
- Fish
What age group is most commonly affected by vitamin E / selenium deficiency?
Most common in young animals but any age can be affected.
What are the clinical signs of vitamin E / selenium deficiency?
- White muscle disease
- Stiffness and paralysis due to skeletal muscle necrosis and mineralization
- Cardiomyopathy (can lead to sudden death when stressed)
- Ill thrift and lethargy (GPs and deer)
- Conjunctivitis (GPs)
- Neurologic signs in birds
How is vitamin E / selenium deficiency treated?
Mild cases:
- Respond to supplementation with vitamin E / selenium injections
Severe cases:
- Poor response
- Supportive care, muscle relaxants and sedatives
How is vitamin E / selenium deficiency prevented?
- Ensure adequate levels in diet (dependent on species, age, and formulation)
- Measure vitamin E serum levels
- Supplement fish and high fat diets
- Follow expiry dates on dry foods
Which animals are prone to thiamin deficiency?
Common issue in fish eaters
- Pelicans
- Penguins
- Marine mammals
- Some snakes amphibians and fish
What is the cause of thiaminase?
Thiaminase is activated after death in fish, the effect is enhanced by freezing
What are the clinical signs of thiamin deficiency?
- Anorexia and weight loss
- Ataxia and limb paralysis
- Tremors and seizures
- Stargazing
- Cardiac failure
- Loss of equilibrium, edema and poor growth in fish
How is thiamin deficiency treated/prevented?
Supplementation of diet with thiamine
30-35 mg/kg of fish for animals on diets that contain thiaminase.
Which species are prone to vitamin C deficiencies and why?
Most primates, bats, cavies (guinea pigs, capybara), some birds (eg. swallows, bulbuls), fish and some cetaceans cannot synthesize ascorbic acid. They lack the enzyme that converts glucose to ascorbic acid.
What does vitamin C deficiency result in?
Defective blood vessels and tooth position
What are the clinical signs of vitamin C deficiency?
- Poor coat and skin condition
- Lameness
- Stomatitis
- Muscle and joint hemorrhage
- “Broken Back Disease” in fish
- Swelling at long bone epiphyses and CC junctions
- Fractures
- Increased susceptibility to infectious disease
- Anorexia
- Diarrhea
How is vitamin C deficiency prevented/treated?
- Commercial diets are fortified (vitamins added) but must be fed within 90 days due to oxidation
- Feeding a balanced diet with green veggies and fruits
What foods have low to no vitamin C?
Seeds and animal tissues
Excess vitamin C can enhance…
Iron toxicity, especially in fruit bats and lemurs.
What is a common problem in various species of captive animals?
Obesity
Includes carnivores, ungulates, birds, primates, reptiles, and amphibians
What are some health issues caused by obesity in captive animals?
- Dystocia
- Hepatic lipidosis
- Atherosclerosis (parrots)
- Pododermatitis
- Uroliths
- Dental disease (rabbits)
These conditions can lead to decreased lifespan and increased strain on the musculoskeletal system.
What dietary factors contribute to urolith development in rabbits?
- Obesity with limited exercise
- Free-choice feeding of alfalfa pellets/hay as adults
- Over-supplementation with vitamins or minerals
What are signs of urinary issues in rabbits?
- Frequent urination
- Straining
- Hunched posture and teeth grinding
- Thick, white urine (sludge)
- Blood in urine
- Loss of appetite
What is the recommended diet for growing or lactating rabbits?
- Commercial legume-based pellets ad lib
- Grass hay ad lib
- Vegetables (handful/day)
What should adult rabbits eat for a proper diet?
- Non-legume based pellets in a measured amount
- Grass hay (ad lib)
- Limited vegetables
A balanced adult diet is critical for maintaining health.
Why is hay important for rabbits?
- High in fiber
- Provides behavioral enrichment
- Reduces aggression and health risks
- Reduces chewing on inappropriate objects = less risk of impaction
- Decreased risk of obesity and pododermatitis
- Reduced risk of uroliths, dental, and infectious disease
What are the dietary recommendations for adult rabbits?
- Non-legume based pellets: 30-60 grams/kg/day
- Protein: 12-14%
- Fiber: 20-25%
- Fat: <2.5%
- Calcium: <1%
- Grass hay ad lib (~30-35% fiber)
What are the dental characteristics of rabbits?
- Continuously growing incisors and molars (hypsodont)
- Incisor growth rate: up to 10-12 cm/year
What are the signs of dental issues in rabbits related to diet?
- Overgrown teeth
- Spurs or points
- ‘Slobbers’
- Anorexia
- GI stasis and dysbiosis
- Hepatic lipidosis
These issues can arise from inadequate fiber intake.
What should the diet for growing rabbits include?
- Commercial alfalfa-based pellets (ad lib)
- 16-18% protein
- At least 16% fiber
- Grass hay (ad lib)
- Limited vegetables
This diet supports healthy growth.
What can result from less than 15% fiber in a rabbit’s diet?
- Diarrhea
- Anorexia
True or False: Obesity in rabbits can lead to hepatic lipidosis.
True
Obese rabbits are at increased risk for liver disease.
What is hemosiderosis/hemochromatosis?
Excessive accumulation of iron in tissues
Which animals are commonly affected by hemosiderosis/hemochromatosis?
- Captive mynahs
- Starlings
- Toucans
- Lemurs
- Marmosets
- Fruit bats
What are the clinical signs of hemosiderosis/hemochromatosis?
- Abdominal/coelomic swelling due to hepatic enlargement
- Weight loss
- Ascites
- Anasarca
What is the etiology of hemochromatosis in captive lemurs?
- Excess dietary iron
- Excess ascorbic acid
- Lack of tannins in diet
DIET IMBALANCE!!
What is hemochromatosis associated with?
There is a strong association between hemochromatosis and hepatic neoplasia
This indicates that iron overload may contribute to liver cancer development.
What diagnostic methods are used for hemosiderosis/hemochromatosis?
- Increased serum iron levels
- Increased serum ferritin levels
- Clinical signs
What pathological findings are associated with hemosiderosis?
- Diffuse iron accumulation without tissue damage
- Enlarged, bronze-colored liver
What pathological findings are associated with hemochromatosis?
Hepatic necrosis
This indicates damage to liver tissue due to excessive iron accumulation.
What are the treatment options for hemosiderosis/hemochromatosis?
- Iron-chelating drugs
- Blood letting
- Reduce or eliminate diet items high in iron & Vitamin C
- Avoid feeding dog food
Treatment focuses on reducing iron levels and dietary management.
Fill in the blank: Hemosiderosis is characterized by _______ without tissue damage.
Diffuse iron accumulation
True or False: Weight loss is a clinical sign of hemosiderosis/hemochromatosis.
True
Weight loss is commonly observed in affected animals.
How are hemosiderosis and hemochromatosis different?
Hemosiderosis can occur without immediate tissue damage, distinguishing it from hemochromatosis.
What urinary system related clinical sign is an emergency in rabbits and why?
Hunching and teeth grinding since the urinary system may be blocked.
