title: Impact of two types of complete pelleted, wild ungulate feeds and two pelleted feed to hay ratios on the development of urolithogenic compounds in meat goats as a model for giraffes.
abstract: Urolith formation has been documented in giraffes and goats. As research in giraffes poses logistical challenges, 16 buck goats were used as a model. The impact of two commercially available, pelleted feeds used for giraffes, ADF-16 and Wild Herbivore (WH), as well as the impact of alfalfa hay and pellet proportions (20% hay:80% pellets, 80P or 80% hay:20% pellet, 20P) on the formation of urolithogenic precursors in goat urine was accomplished in a 2 × 2 factorial balance study. Complete diets contained 0.60, 0.32, 0.35 and 0.26% phosphorus (P) with calcium:P ratios of 1.60, 4.16, 3.06 and 5.23, for 80P-ADF-16, 20P-ADF-16, 80P-WH and 20P-WH respectively. Total faeces and urine were collected over two 5-day periods to assess N and mineral balance. Fresh urine samples were collected and evaluated microscopically for urolithic crystal content. Urinary nitrogen (N) was lower and N retention was higher in goats fed 80P diets (p < 0.05). Intake of P was greatest for goats fed 80P-ADF-16; however, urinary P excretion and P retention were not affected by treatment. Crystal scores were higher in animals receiving 80P diets (p = 0.08), with crystals being composed predominantly of calcium phosphate. Urine pH was alkaline (>8) for all treatments. Urinary P concentration, a risk factor for urolithiasis, was highest (p ≤ 0.06) in the 80P-ADF-16 treatment (0.38 vs. 0.01, 0.02 and 0.04 mg/dl for 20P-ADF-16, 80P-WH and 20P-WH respectively), reflecting its highest dietary P level. Further investigation is recommended to determine the long-term effects of these diets on urolithogenic compound formation.
authors.affiliation: Department of Animal Science, North Carolina State University, Raleigh, NC 27695, USA.
authors.forename: K
authors.initials: K
authors.lastname: Sullivan
authors.forename: S
authors.initials: S
authors.lastname: Freeman
authors.forename: E
authors.initials: E
authors.lastname: van Heugten
authors.forename: K
authors.initials: K
authors.lastname: Ange-van Heugten
authors.forename: B
authors.initials: B
authors.lastname: Wolfe
authors.forename: M H
authors.initials: MH
authors.lastname: Poore
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000822:Animal Husbandry / Q000379:methods; D000818:Animals; D000835:Animals, Wild; D000866:Antelopes; D002118:Calcium / Q000652:urine; D002136:Calcium, Dietary / Q000032:analysis / Q000378:metabolism; D003404:Creatinine / Q000652:urine*; D004063:Digestion; D004305:Dose-Response Relationship, Drug; D005511:Food Handling; D006041:Goats / Q000502:physiology*; D009751:Nutritional Requirements; D009753:Nutritive Value; D010758:Phosphorus / Q000652:urine; D016226:Phosphorus, Dietary / Q000032:analysis / Q000378:metabolism; D052878:Urolithiasis / Q000517:prevention & control / Q000662:veterinary
chemical_list: D002136:Calcium, Dietary; D016226:Phosphorus, Dietary; D010758:Phosphorus; D003404:Creatinine; D002118:Calcium