hypocalcemia Flashcards

Question

follow up for milk fevertreatment? what if poor response?

Answer 1

 Did not respond to treatment? > Pre-treatment blood sample, analyze results  Early decisions on re-treatment > More Ca within 12 hours, lifting (within 4 hours), etc  Recommend Euthanasia if no response within 24-48 hours > Our responsibility to help ensure cow welfare is upheld

Answer 2

 Dystocia  Retained placenta, metritis, prolapsed uterus  LDA – comes days later and probably associated with other health issues  Teat trauma, mastitis  Ischemic muscle necrosis  Nerve compression > dysfunction  Musculoskeletal trauma when trying to rise  Aspiration pneumonia

Answer 3

IONIZED CALCIUM (iCA)  Bioactive form of blood calcium, capable of intracellular access  Cow-side testing  High cost of the device + Cartridges  Cut-point SCH <1.17 mmol/L - in a healthy cow, ~50% of Ca in circulation >but iCa-tCa relationship changes around parturition Few studies base postpartum disease prediction on iCa, perhaps due to its cost and practicality <><> TOTAL CALCIUM (tCA = iCa + Ca bound to proteins)  Affected by serum Total Protein concentration  Ca is bound to albumin; this relationship is pH-dependent  Inexpensive  SCH cut-point found: from 1.88 to 2.35 mmol/L  Cow-side testing not valid/available  Most studies base postpartum disease prediction on tCa - send to lab, results in ~24h Or Benchtop Clinical Chemistry Analyzer

Answer 4

-there is a transient presentation which may not be bad in the long run - but also persistant and delayed forms...

Answer 5

* Milk fever can almost entirely be prevented through diligent implementation of a DCAD program > There is no clear threshold of blood [Ca] for clinical signs * The of 2.0 mmol/L blood total Ca soon ~ 1 day after calving to define subclinical hypocalcemia is not well supported by evidence * Maintenance of blood Ca > 2.15 mmol/L at 1-4 DIM is a more desirable target * There is mixed, but generally scant evidence for calcium supplements to prevent disease other than milk fever * Supplements should be targeted to multiparous/high-risk cows

Answer 6

* One study supplemented cows with oral calcium after calving found: > an increase in milk production in higher producing cows > decrease in health problems among lame cows * Calcium supplements can reduce clinical milk fever * Calcium supplements can modestly increase blood [Ca] in cows with low blood [Ca] (Miltenburg et al, 2016; Blanc et al 2016; Martinez et al 2016; Amanlou et al 2016) * Effects of calcium supplements on risk of disease: > None Miltenburg et al, 2016 > None to worse Martinez et al 2016 a, b > Better Amanlou et al 2016

Answer 7

An old approach to control hypocalcemia CHALLENGING GOAL: negative calcium balance in the last weeks pre calving > Increase concentrations of PTH <><> some try to use calcium binder in GI tract to acheive this... (Zeolite A)

Answer 8

Negative DCAD > milkd metabolic acidosis > quicker response to low blood CA -Provide excess anions in ration in order to counteract potassium effects on blood pH... improved response to PTH <><> Acidify diet in late dry cow period: 1. Reduced potassium (K) - Forages = high potassium (vs. corn silage is lowest) - Reduce crop fertilization with manure 2. Calculate “DCAD” ...and Add Urine Acidifiers to Diet <><> - anioic supplement added to the prepartum ration > lower pH > Increase urinary Ca excretion > Around parturition ↑ bone resorption ↑ efficiency of intestinal Ca absorption > Quicker response to low blood Ca

Answer 9

Acclimatize 3 - 4 weeks pre-partum <><> Anionic salts  Magnesium/calcium/ammonium sulfate  Magnesium/calcium/ammonium chloride  HCl <><> Other considerations:  Limit intake of strong cations (Na+ and K+)  Limit concentration of P (high concentration of P decreases calcitriol concentration)  Magnesium level - necessary for bone resorption  Dietary Ca % – High vs Low – Lack of consensus  Palatability (?)

Answer 10

PROS - decreased Milk fever - decreased Subclinical hypocalcemia - decreased Peripartum diseases - decreased Culling - increased Reproductive performance - increased Milk yield CONS - costly product - palatability? - extra labour (monitoring)

Answer 11

40 to 50% reduction in cases

Answer 12

* Assessed effect of reduced DCAD (not necessarily negative) * Reduced DMI prepartum but greater postpartum * Overall, benefits in multiparous, not heifers

Answer 13

Urine pH in close-up group  Close-up group (within 3wks before parturition)  Once per week  Target urine pH: – 6.0 - 6.5 Holstein – 5.8 - 6.2 Jerseys – ≥ 80% of cows in range

Answer 14

Also occurs in older beef cows and ewes during late pregnancy – Particularly when carrying twins! – Decreased osteoclastic activity – Often poor nutrition contributes – Precipitated by a stress (climate change, feed shortage, etc)

hypocalcemia Flashcards

(38 cards)