BCSE - Basic and Clinical Sciences Examination Clinical Nutrition and Metabolism Questions and Answers Flashcards

Which nutrient deficiency causes 'white muscle disease' (nutritional myodegeneration) in calves and lambs?

Answer: Selenium and/or vitamin E deficiency

White muscle disease results from inadequate selenium and/or vitamin E, antioxidants that protect muscle membranes from oxidative damage.

What is the metabolic basis for pregnancy toxemia (ketosis) in ewes?

Answer: Negative energy balance in late gestation causing mobilization of fat and accumulation of ketone bodies

In late gestation with multiple fetuses, the ewe's energy demands exceed intake, forcing hepatic fat mobilization and ketogenesis that overwhelms clearance capacity.

The amino acid taurine is conditionally essential in cats primarily because cats have limited ability to do which of the following?

Answer: Synthesize taurine from cysteine due to low cysteine sulfinic acid decarboxylase activity

Cats have very low hepatic cysteine sulfinic acid decarboxylase activity, severely limiting endogenous taurine synthesis from cysteine.

Hypophosphatemia in postparturient dairy cows is most commonly associated with which condition?

Answer: Downer cow syndrome following hypocalcemia (milk fever)

Severe hypophosphatemia is a common sequela to milk fever and contributes to recumbency by impairing ATP production needed for muscle contraction.

Which vitamin is required for synthesis of clotting factors II, VII, IX, and X via gamma-carboxylation of glutamate residues?

Answer: Vitamin K

Vitamin K is the essential cofactor for gamma-glutamyl carboxylase, which activates the vitamin K-dependent clotting factors by carboxylating glutamate residues.

A dog presenting with dilated cardiomyopathy is placed on a grain-free diet; which nutritional deficiency has been epidemiologically associated with this presentation?

Answer: Taurine deficiency linked to legume-heavy, grain-free formulations

The FDA investigated a link between grain-free diets high in legumes and taurine-deficiency dilated cardiomyopathy in dogs, particularly golden retrievers.