NAVLE® Question of the day

MO TU WED TH FR

August 8, 2024

NAVLE

A four-month-old calf from a small beef herd in Louisiana presents with a fracture of the right metatarsus.

He was normal last night. The owner found the calf this morning after rounding up the herd for deworming.

This is the fifth calf this season with fractured bones.

One had a vertebral fracture, two calves had humeral fractures, and one other had a cannon bone fracture.

Which one of the following choices is the most likely problem in this herd?

A - Hypovitaminosis D

B - High dietary calcium

C - Low dietary protein

D - Low dietary copper

E - High dietary phosphorus

Sorry. You chose "A - Hypovitaminosis D" but the correct answer is "D - Low dietary copper"

Low dietary copper levels (Cu) causes bones of growing animals to be brittle because they do not develop the normal trabecular structure.

Higher fracture rates are seen in Cu deficient than in Cu replete animals. In areas with high levels of molybdenum (Mb) in the soil, Cu levels are often low. Mb interferes with absorption of Cu, hence Mb excess results in Cu deficiency.

Pathologic fractures are more common during periods of exertion, such as the morning round up. Rough handling exacerbates the number of fractures.

Treatment of Cu deficiency includes copper glycinate injections, and feeding of mineral mixes with Cu. Copper boluses can also be given.

Pathologic fractures can be seen with hypovitaminosis D growing cattle, but this is unlikely in beef cattle on pasture, esp. in the southern United States where there's plenty of sunlight. Occasionally seen in northern cows in winter or show calves housed primarily indoors.

Calcium-deficient calves may also develop a similar syndrome of pathologic fractures.

Image courtesy of Dr. Lisle George.