Endocrine3- Calcium in LA
Card Set Information
Endocrine3- Calcium in LA
Low ionized calcium leads to clinical signs, which include...
muscle weakness or tetany (species dependent), neurologic deficits
Ca2+ is responsible for ________; cows with low iCa2+ inhibits ___________, leading to... (2)
stabilization of neuronal membranes; Ach release (opposite of dogs); hypothermia and flaccid paralysis (also opposite of dogs).
In a cow, failure of Ach release leads to _______.
Causes of hypocalcemia in a cow. (9)
, sepsis, vit D deficiency, malabsorption, oxalates (oxalate-containing plants), Ph enemas, nutritional secondary hyperparathyroidism, hypoalbuminemia, CKD
Some cows have reduced _________ with age, increasing their risk for _____________.
PTH receptors; PTH-independent hypocalcemia
If PTH is high, why is calcium low?
temporary inability of target organs to respond to PTH because of low calcitonin, high estrogen, and high cortisol (antagonizes vit D absorption from GI)
Why do hypocalcemic cows become alkalotic?
anorexia and GI stasis--> udder still removing calcium from the blood
Hypocalcemia usually occurs in...
multiparous cows within 48hrs of gestation
In small ruminants, hypocalcemia is thought to be _____________.
_________ looks the same as milk fever; it can be brought on by administration of __________.
Hypokalemia; dextrose (CMPK)
Clinical signs of stage 1 milk fever (subclinical). (8)
, reduced appetite, hyperexcitable, tremors, unsteady, restless, mouth open, gasping
Clinical signs of stage 2 milk fever. (12)
, depression, anorexia, S-curved neck, dry muzzle, hypothermia, dilated pupils, relaxed anal sphincter, decreased heart sounds, tachycardia, rumen stasis, uterine inertia
Clinical signs of stage 3 milk fever.
, inability to rise sternal, flaccid muscles, bloat, aspiration pneumonia
Pre-partum differentials for signs of hypocalcemia. (3)
musculoskeletal injury, uterine disease, grass tetany
Post-partum differentials for signs of hypocalcemia. (7)
septic metritis, septic mastitis, musculoskeletal, grass tetany, traumatic reticuloperitonitis (hardware- stabs heart when contracts during parturition), abomasal volvulus, metabolic (milk fever, nervous ketosis)
Treatment of hypocalcemia in a cow.
calcium gluconate slowly while auscultating heart
How do you prevent milk fever?
feed DCAD diet (want negative DCAD), feed anionic salts (sulfates or chlorides)--> induce metabolic acidosis--> increased Ca and Mg absorption
How do you detect if the DCAD diet is working?
test pH of urine--> should be acidic
Mean pH values of urine in pre-fresh dry cows should be ________.
Anionic salts work best when _________ is high.
In order for the DCAD diet to work, it must be fed ___________.
at least 10 days prior to calving