EVALUATION OF THE URINARY ALLANTOIN-CREATININE RATIO AS A NUTRITIONALINDEX FOR ELK

Citation
Ra. Garrott et al., EVALUATION OF THE URINARY ALLANTOIN-CREATININE RATIO AS A NUTRITIONALINDEX FOR ELK, Canadian journal of zoology, 75(9), 1997, pp. 1519-1525
Citations number
23
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Zoology
Journal title
ISSN journal
0008-4301
Volume
75
Issue
9
Year of publication
1997
Pages
1519 - 1525
Database
ISI
SICI code
0008-4301(1997)75:9<1519:EOTUAR>2.0.ZU;2-Z
Abstract
We conducted experiments with captive female elk (Cervus elaphus) to e xplore the utility of allantoin:creatinine (A:C) ratios as a noninvasi ve index of nutrition in free-ranging ungulates. Pens of animals were assigned to one of four dietary treatments, each treatment being given to 6 animals. One treatment involved gradually increasing the daily m etabolizable energy intake (MEI) from approximately 650 to 1200 kJ met abolizable energy (ME)/kg body mass (BM)(0.75) in weekly increments ov er 8 weeks. In a second treatment, daily MET was decreased in a simila r manner from approximately 900 to 250 kJ ME/kg BM0.75. Urine samples (96 in total) were collected from each animal in these treatments 5 da ys after each change in diet. Two additional treatments involved relat ively large and abrupt changes in daily diet ranging from 120 to 500 k J ME/kg BM0.75. With successive diets being alternately increased and decreased at 2-week intervals for 10 weeks. Urine samples (179 in tota l) were collected from each animal 3, 5, and 13 days after a dietary c hange was initiated. The underlying relation between A:C ratio and MEI was consistent among the four treatments and indicated that the urina ry A:C ratio is a reliable index of dietary intake in elk across a var iety of dietary regimes. A:C ratios responded relatively quickly to ch anges in diet, indexing the dietary intake of the animals during a sev eral-day period immediately prior to the time the urine was voided. Th e results of this and previous studies indicate that the urinary A:C r atio has significant potential as a nutritional index for wild ruminan ts; however, we recommend additional research before the use of A:C ra tios is integrated into ecological or management applications.