Question

This level increases due to renal failure (secondary renal hyperparathyroidism). Decreases are seen in some downer cows and as part of the stress pattern in horses and small animals.

a) Calcium (Ca2+)
b) Phosphorus (P)
c) Magnesium (Mg2+)
d) Potassium (K+)

Answer 1

The level that increases with renal failure is Phosphorus (P). This rise is due to the kidneys' failure to excrete phosphate efficiently, which results in hyperphosphatemia and a decrease in serum calcium levels.

Step-by-step explanation:

The level that increases due to renal failure (secondary renal hyperparathyroidism) and decreases in some downer cows, as described, is Phosphorus (P). This is because there is a reciprocal relationship between serum calcium and phosphate concentrations. In conditions of hyperparathyroidism, there's increased serum calcium that leads to increased phosphatase activity and urinary calcium excretion, but this condition also typically results in decreased serum phosphate due to increased excretion. However, in renal failure, the kidneys are unable to excrete phosphate efficiently, leading to hyperphosphatemia and a consequent fall in serum calcium.