What fraction of calcium in the blood is most important biologically?
List what you would need to measure to 100% diagnose Hypothyroidism
T4
Free T4
TSH
From one way valve or from the spot you can put in meds (first photo)
See photo:

What do cows eat
ERIN IS NOT ALLOWED TO ANSWER
Total mixed ration
What is the normal function of Vitamin D
Vitamin D increases Ca, P concertation
T/F Bone, liver and the kidneys are the main organs involved in Calcium homeostasis
F, Bone, Kidney, Intestine- not liver
Sophie
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Sores on belly/bald
Begging for food/eating more
Large distended belly "pot belly"
Increased water intake/increased urination
Has gained 2 lbs in last month
PE: Bright, alert, responsive; agreeable but very nervous on exam.
Low Dose Dexamethasone Suppression Test:
Cortisol, Baseline ---118 High
Cortisol, low dose dex 4h--- 46 High
Cortisol, low dose dex 8h--- 60 High
What would you diagnose?
Cushing's Disease
Where is the correct placement to put a weight tape, point on horse
ERIN NOT ALLOWED TO ANSWER
Ta-Da!
Important characteristics to look for when observing hay quality
Smell- sweet, moldy
Color- too green (could be fake), green, and yellow/brown
Feel- hard, soft
Moisture- wet, dry
What is the main effect vitamin D has on the parathyroid glad
enhances effect of PTH in nephron: increases Ca reabsorption from renal tubes
PTH effect on bone
Hint: process of mineralization
IMPORTANT- osteoclasts cannot bind unmineralized bone matrix
-PTH binds to osteoblast -> osteoblast react from bone and secrete collagenase -> erosion of unmineralized layer of the matrix-> osteoclast gain access to mineralized bones
Golly The Goat- Has a Goiter
Golly has a large bump under his chin
Golly the goat (3 year old Boer castrated). On the farm some of the
baby goats have been born hairless and dead.
Blood work
T3 0.3 (0.5 to 7.0) ng.ml)
T4 2.7 ( 3.5-9) ng/ml)
TSH 0.05 (0.01-0.02 mlu/ml)
Explain using the feedback loops/ other class discussions answer; Why does Golly have a goiter?

The body needs iodine to produce thyroid hormone. If you do not have enough iodine in your diet, the thyroid gets larger to try and capture all the iodine it can, so it can make the right amount of thyroid hormone. So, a goiter can be a sign the thyroid is not able to make enough thyroid hormone.
What is the max insulin level for a healthy horse?
range 20-45
Why is the Ca:P ratio important in horse diets?
PAOLA IS NOT ALLOWED TO ANSWER
Because phosphorous competes with Ca for absorption in the gut
poor Ca absorption poor bone health
Nutritional Secondary Hyperparathyroidism: Giant Head Disease
What is the effect Vitamin D had on the intestine
Increase absorption of P and Ca
Parathyroid Hormone (PTH) main effect is to?
PTH's effect on kidney?
PTH effect on intestine?
1-increase iCa2 and decrease P
2-increase renal tubular Ca reabsorption
decrease renal tubular P reabsorption
↑ renal formation of 1,25-dihydroxyvitamin D
(calcitriol; most biologically active metabolite)
3- Increase absorption on Ca
In the case of Big Head disease what is the medical diagnosis and why?

hyperparathyroidism!
'Big Head' is a calcium deficiency disease induced by a diet with a persistent lack in calcium, excess in phosphorus and/or imbalanced calcium to phosphorus ratio. This results in weak and misshapen bones. This is most noticeable in the horse's head – hence the name Big head disease.
When preforming and plotting a glucose curve in a horse at what time after Karo Syrup consumption do you expect to see the highest point on your graph?
60-90min after consumption of Karo Syrup
What is the importance of having <65% NDF in a horses diet
NDF is a measure of insoluble fiber
Low NDF means lowering change for impaction colic
What hormone does V D produce?
Sorry trick question!
N/A- It itself is a steroid hormone
Identify the net effect on the from of the specific hormone...
Parathyroid hormone: Decrease, Increase
----iCa (ionized Ca), P (phosphorus)
Vitamin D: Decrease, Increase
----iCa (ionized Ca), P (phosphorus)
Calcitonin: Decrease, Increase
----iCa (ionized Ca), P (phosphorus)
PT- increase;decrease
VD- Increase;Increase
Calcitonin- decrease,decrease
Bandit the Ferret

The owner is concerned about gradual onset of alopecia and more
recently lethargy and occasional tremors. Most recently the ferret fell
over in his case. Seems to be salivating more than normal.
PE: Bandit is BAR but lethargic. Pulse, CRT, systems review normal.
Endocrine Results for Bandit the Ferret
Procedure
Insulin (fasting) 70 High
Glucose (fasting) 44 Low
Ratio (fasting) 1.59 High
Diagnosis: insulinoma
Using feedback loops and class discussions answer the following questions?
What are effects of excess insulin?
How hypoglycemia contributes to the clinical signs?
How do the clinical signs and blood work support a diagnosis of insulinoma
1- low blood glucose, Fatigue, shakiness
2- A low blood glucose level triggers the release of epinephrine (adrenaline), the “fight-or-flight” hormone. Epinephrine is what can cause the symptoms of hypoglycemia such as thumping heart, sweating, tingling, and anxiety.
3-low blood sugar- tumors in pancreas are making extra insulin causing hypoglycemia.
If I have a 1110lb horse, what would be the dose of Karo Syrup you would dispense? ml/kg
1110 / 2.2= 504 kg
504 kg x 0.15 ml/kg (karo) = 75.6 ml
What does NSC stand for and what do you want this level to look like for an insulin resistant horse (High/Low)
nonstructural carbohydrates
Low (10%)
What inhibits Calcitriol production?

FGF-23- that makes 1 alpha-hydroxylase, and 24-Hydroxylase
FGF-23 stops making 1 alpha-hydroxylase (direct shut off)
FGF-23- increases 24-Hydroxylase that side steps the chain and breaks down D2 into D metabolites