Dietary Control of Cystinuria in Maned Wolves (Chrysocyon Brachyurus)

The maned wolf (Chysocyon brachyurus) is an endangered South American species of canid, whose numbers in both the wild and captivity are threatened in part by a condition called cystinuria. In humans and rats, cystinuria is caused by mutations of the rBAT gene, expressed in intestinal mucosal cells and renal tubules. In dogs, only renal tubules are affected. Cystinuric individuals exhibit impaired capacity for reabsorption of the sulfur amino acid cystine. Consequently, excess cystine accumulates in the urine. In acidic conditions, cystine may precipitate into uroliths, potentially obstructing the urethra and ultimately causing bladder rupture or kidney damage. Treatments include medical management and dietary modification. Test diets differing only in levels of cystine were fed to 15 maned wolves in a cross-over design. Apparent digestibility calculations suggest the diets were well received, well utilized and improved fecal quality. The low cystine diet significantly reduced urinary excretion of cystine (P<0.05). Mean urinary concentrations of cystine were 341±45.87 mg/L or 2.78±0.326% total urinary nitrogen for the low cystine diet; and 475.8± 47.80 mg/L or 4.01± 0.342% for the high cystine diet. Water balance studies was determined three maned wolves, using orally administered deuterium oxide. Urine samples were collected daily for seven days, purified by sublimation, and analyzed by infrared spectrometry. It was determined that total body water, water turnover rate and body composition were 17.2 L, 2.3 L/d, and 20.5% fat; 79.5% lean, respectively. These results are comparable to published values for dogs.

Department dc:contributor.department

Avian and Animal Sciences

Year dc:date.issued

1998

Author dc:creator

• Boniface, Jennifer

Advisor dc:contributor.advisor

• Soares, Joseph H., Jr.

Language dc:language.iso

en_US

Identifier

https://doi.org/10.13016/b5i3-eswe

Dc Identifier Other

ILLiad # 1523515

OAI identifier oai:identifier

oai:drum.lib.umd.edu:1903/29074