Large Animal/Equine Disease Flashcards
Covers: Equine thyroid dz, Obesity in horses, Ketosis and Equine metabolic syndrome, Disorders of the pituitary gland, Equine chronic weight loss, and Equine and Caprine urolithiasis lectures
What do you expect to result from a TSH stimulation test in a horse without hypothyroidism?
(Thyroid hormones should be increased on the post-test)
What age of horse has a normally elevated T3 and T4?
(Foals)
What are two causes of congenital hypothyroidism?
(Too little/much iodine in dam’s diet or dam ingesting goitrogenic plants)
(T/F) A benign adenoma should be at the very top of your differential list in a horse with an enlarged thyroid.
(T)
(T/F) Benign adenomas of the thyroid gland typically cause a fluctuation in thyroid hormones.
(F, are typically non-functional meaning they do not affect the function of the thyroid gland)
What is the point system used for body condition scoring in horses?
(9-point system)
What is the lowest score that is considered overweight in a horse?
(7 and greater)
What is the ideal body condition score range for a horse?
(4-6)
What is the horse term for the area that should be evaluated in a horse to assess muscle condition?
(The topline which is along the back)
(T/F) You should base your diet plan for a horse on their ideal body weight i.e. you’ll multiply their ideal body weight by 2% and that will give you the dry matter weight they should be fed.
(F, should be based on current body weight, otherwise, you are restricting their calories too quickly)
What type of forage should be avoided when feeding a horse that is losing weight because it is more energy dense than grass?
(Alfalfa hay)
Do you want the NDF of the feed you are feeding to an over-conditioned horse to be high or low?
(High)
If you assessed a 620 kg horse to have a body condition score of 7/9:
How much weight does that horse need to lose in kgs to reach a body condition score of 5/9?
(45.5 kgs)
If you assessed a 620 kg horse to have a body condition score of 7/9:
What is the ideal weight of this horse in pounds? x
(1,264 lbs)
If you assessed a 620 kg horse to have a body condition score of 7/9:
In pounds, how much dry matter should this horse be fed?
(27.3 lbs)
If you assessed a 620 kg horse to have a body condition score of 7/9:
In pounds, how much hay should be fed ‘as fed’?
(30.3 lbs)
If you assessed a 620 kg horse to have a body condition score of 7/9:
Ideally, how long should it take this horse to lose the desired weight?
(2-4 months)
What is the term for ‘the collection of risk factors highly associated with an increased risk of hyperinsulinemia-associated laminitis and other morbidities’?
(Equine metabolic syndrome)
What are the two main risk factors associated with equine metabolic syndrome?
(Obesity and insulin dysregulation)
What condition may EMS co-exist with in older horses?
(PPID)
What type of conditions leads to the selection of genes that improve a horse’s metabolic efficiency, promote obesity, and increase appetite when food is plentiful; i.e. genes that predispose a horse to equine metabolic syndrome?
(Famine conditions)
What do adipocytes secrete, because they are an active endocrine organ, that has local and systemic effects that can induce a chronic inflammatory state in a horse with regional or generalized adiposity?
(Adipokines)
What effect does either resting or postprandial hyperinsulinemia have on insulin resistance in a horse?
(Hyperinsulinemia worsens insulin resistance by down-regulating insulin receptors)
What does having either resting or postprandial hyperinsulinemia predispose a horse to developing?
(Laminitis)
What is the primary insult related to endocrine laminitis whereas most other causes of laminitis are related to inflammation?
(The primary insult is the alteration of form and function of vasculature)
What are the triggers for laminitis in EMS? Two answers.
(A high carbohydrate meal and any other normal cause of laminitis in a horse)
How long should concentrate/grain not be fed prior to taking a resting insulin measurement?
(4 hours)
If resting insulin is normal in a horse you suspect might have EMS (based on signalment), what other tests can be performed?
(Oral sugar test and combined glucose-insulin test)
(T/F) A combined glucose-insulin test/insulin tolerance test should be performed on a fasted horse.
(F, this test is performed on horses in fed conditions, horse should not be fasted)
Does pain and/or exercise increase or decrease an animal’s resting insulin?
(Decrease)
(T/F) The initial dietary management of a horse with EMS should include removing all concentrate from their diet, removing high-sugar treats from their diet, and turning them out on pasture as much as possible.
(F, turning out on pasture is strongly discouraged)
What are the four time frames in which nonstructured carbohydrates will be high in grazing pastures (so turning horses with EMS out onto pastures during these times is a no-no)?
(When grass is growing quickly i.e. spring, just prior to summer droughts, after a heavy rain, and when grass is entering winter dormancy)
What drug is used, concurrently with a restricted diet, to ramp up a horse’s metabolic rate to help them lose weight?
(Levothyroxine)
What drug has a local effect in a horse’s gut that prevents hyperinsulinemic responses to food?
(Metformin)
(T/F) All dairy cows are in negative energy balance during the first 8 weeks of lactation.
(T)
What results from the late gestation demands of a fetus, lactation causing sudden and drastic increases in energy demands, and the concurrent decrease in feed intake of early gestation cattle? Two answers.
(Negative energy balance and high demand for glucose)
How are non-esterified fatty acids processed in the liver? Three answers.
(Complete oxidation for energy (gets overwhelmed quickly), incomplete oxidation into ketone bodies, and re-esterification into fatty acids)
What are the acceptable screening tests for subclinical ketosis?
(Testing for BHB in milk and urine ketones but they have to be at least in the ‘small’ category (bc urine ketones can be falsely positive in normal animals))
What is the mainstay treatment for ketosis?
(Limit mobilization of fat by providing glucose source → IV dextrose, propylene glycol enterally, glucocorticoids, insulin, get cow to eat)
In a normal horse, dopaminergic neurons in the hypothalamus have an inhibitory or stimulatory (choose one) effect on the breakdown of POMC in the pars intermedia.
(Inhibitory)
In a normal horse, thyrotropin-releasing hormone stimulates or inhibits (choose one) the breakdown of POMC in the pars intermedia and distalis.
(Stimulates)
What age of horse is associated with PPID?
(Older)
How can you tell the difference between a horse with PPID and hypertrichosis and a Bashkir Curly horse (besides the owner telling you 15 times)?
(Curly horses typically have a curly mane and tail as well while horses with PPID-induced hypertrichosis only have curly hair on their body)
Why are horses with PPID at risk for chronic infections?
(They are immunosuppressed due to the excess POMC breakdown products)
Why might a horse with PPID present with ataxia and blindness?
(That indicates there is an extension of the enlarged pituitary gland that is compressing the brain)
What are the two endocrine tests with proven utility in the diagnosis of PPID?
(Basal ACTH and thyrotropin-releasing hormone stimulation test)
What is the mechanism of action of pergolide that makes it useful in the treatment of PPID?
(It is a dopamine agonist)
What are the normal results from the glucose absorption test (which is used to help in diagnosing a malabsorptive disease)?
(Blood glucose should double by the 90-120 minute mark and should return to resting values by 360 minutes)
How long should you take to transition a horse to a new diet?
(7-10 days)
What is the causative agent of proliferative enteropathy in foals?
(Lawsonia intracellularis)
What do you expect to see on ultrasound of a foal with proliferative enteropathy?
(Thickened but not distended small intestines with normal to slow motility)
What is the preferred treatment for proliferative enteropathy of foals?
(Injectable oxytetracycline)
(T/F) Equine patients tend to develop a single, large bladder stone.
(T)
Equine urolithiasis is more common in males or females (choose one).
(Males)
What are the most common uroliths in equine patients?
(Calcium carbonate uroliths → bc they excrete so much calcium in their urine and their alkaline urine favors crystal formation)
(T/F) Urolithiasis is the single most common urinary tract disease in small ruminants.
(T)
What type of stones are associated with high grain diets that typically have a low calcium:phosphorus ratio and alkaline urine in small ruminants? Two answers.
(Struvite and apatite stones)
What type of stones are associated with legume diets and alkaline urine in small ruminants?
(Calcium carbonate stones)
What about the small ruminant penis prevents effective urohydropulsion?
(The fact that it is fibroelastic, it will clamp down and not let the water flush through appropriately)
What is used to dissolve small ruminant stones?
(Walpole’s solution)
What is the appropriate calcium to phosphorus ratio to prevent formation of struvite/phosphate stones?
(2:1)
What is the purpose of increasing dietary roughage in the prevention of phosphate stones?
(Dietary roughage increases salivation and will increase excretion of phosphate with the saliva)
What is administered to small ruminants to acidify their urine?
(Ammonium chloride)