Objective—To compare the nutritional value of corn
gluten meal (CGM) and meat meal (MM) as a dietary
source of protein in dry food formulated for adult cats.
Animals—8 healthy adult cats (4 males and 4
Procedure—Diets containing CGM or MM as the
main protein source were each fed for a 3-week period
in a crossover study. Digestibility and nutritional
balance experiments were conducted during the last
7 days of each period. Furthermore, freshly voided
urine was obtained to measure urinary pH, struvite
crystals, and sediment concentrations.
Results—Daily food intake and dry-matter digestibility
were significantly higher for the MM diet. Fecal
moisture content also was higher for the MM diet.
Apparent nitrogen (N) absorption and N retention
were higher for the MM diet, even when values were
expressed as a percentage to account for differences
in N intake. Urinary pH, struvite activity product, number
of struvite crystals in urine, and urinary sediment
concentrations were not different between diets.
Retention of calcium, phosphorus, and magnesium
was lower for the CGM diet, and cats lost body calcium
and magnesium when fed the CGM diet.
Conclusion and Clinical Relevance—Meat meal
was superior to CGM as a protein source in dry foods
formulated for cats, because dry-matter digestibility
and N utilization were higher for the MM diet. In addition,
net loss of body calcium and magnesium for the
CGM diet suggests that mineral requirements
increase when CGM is used as a protein source. (Am
J Vet Res 2002;63:1247–1251)