URINARY INDEXES IN LLAMAS FED DIFFERENT DIETS

Indices of renal function and damage were measured in 12 healthy male adult Ilamas fed a diet of mixed alfalfa/grass hay (mixed hay) and wat er ad libitum. Using a collection bag fitted over the preputial area, urine samples were collected at 6, 12 and 24 hours. Serum samples were obtained concurrently to determine endogenous creatinine clearance (C L), total (TE) and fractional excretion (FE) of electrolytes (Na, K, C l, P), electrolyte CL, wine and serum osmolality, urine enzyme activit ies (gamma-glutamyltransferase and N-acetyl-beta-D-glucosaminidase), a nd urine protein concentration. Urine production was quantified. Three months later, 10 of the 12 Ilamas were fed a grass hay diet and water ad libitum. Similar samples were obtained, and similar measurements w ere made. Urine production was higher when the volume for Ilamas fed m ixed hay ranged from 628 to 1,760 ml/ 24 h, with a median of 1,307.5 m l/24 h, compared with a range of 620 to 1,380 ml/24 h and a median of 927.50 ml/24 h for Ilamas fed grass hay. Median urine osmolality was h igher in Ilamas fed mixed hay (1,906 mOsm/kg of body weight, with a ra nge of 1,237 to 2,529 mOsm/kg), compared with Ilamas fed grass hay (1, 666 mOsm/kg, with a range of 1,163 to 2,044 mOsm/kg). Creatinine ct di d not vary significantly over time for either diet. Median creatinine CL was higher for Ilamas fed mixed hay, compared with Ilamas fed grass hay-0.78 ml/min/kg, with a range of 0.20 to 1.83 ml/min/kg vs 0.45 ml /min/kg, with a range of 0.13 to 3.17 ml/min/kg. Clearances for K and C1 varied significantly among the periods. However, median CL for Na a nd P did not vary over time for either diet. Overall values for these electrolytes in Ilamas fed mixed hay and grass hay diets were: CL(Na), 0.001 and 0.002 ml/min/kg and CLp, 0.0006 and 0.0004 ml/min/kg, respe ctively. The FE rates of K, Cl, and P did not vary significantly over time for either diet. Median respective FE for these electrolytes in t he Ilamas fed mixed hay and grass hay diets include: FE(K), 84.90 and 63.10%; FE(Cl) 0.85 and 1.30%; and FEp, 0.10 and 0.10%. Fractional exc retion of Na varied over time for both diets and could not be expresse d accurately as an overall median. Median respective TE of electrolyte s for Ilamas fed the mixed hay and grass hay diets were: TE(Na), 0.007 and 0.03 mEq/kg/h; TE(Cl) 0.04 and 0.06 mEq/kg/h; and TEp, 0.0002 and 0.00 mg/kg/h; TEK varied significantly (P < 0.05) over time for both diets. Urine gamma-glutamyltransferase activity changed significantly (P < 0.05) over time. Urine N-acetyl-beta-D-glucosaminidase activity w as influenced by an interaction between diet and time. Median urine pr otein concentration was 26.0 mg/dl, with a range of 11.0 to 73.0 mg/dl for Ilamas fed mixed hay, and was 28.0 mg/dl, with a range of 16.0 to 124.0 mg/dl for Ilamas fed grass hay.