170 Effects of Dietary Phytogenic Supplementation to a Finishing Diet on Intake, Digestibility, Nitrogen Balance and Carcass Measures

Dietary manipulations to include tannins can change the proportion and amount of nitrogen (N) excreted in the urine and feces as well as improve N-use efficiency in ruminants. Our objective was to determine the effects of different levels of phytogenic supplementation (Actifor®) on intake, digestibility, carcass measures, and N balance of lambs offered a corn-based finishing diet. Twenty-six lambs (31.5 ± 5.39 kg BW) were allocated randomly to 1 of 3 corn-based finishing diets (85% concentrate) that were offered for ad libitum consumption. Lambs were housed individually in 1 × 1.5-m pens with plastic-coated grate flooring (n = 18; 6/trt) or 1.5 × 4.3-m pens with rubber mat flooring (n = 8; 2 or 3/trt). Diets were not supplemented or supplemented with 4 or 8 g/d of Actifor® (n = 8, 9, and 9 lambs/trt, respectively). A 7-d total fecal and urine collection period (n = 6 lambs/trt) began on d 43. On d 50, rumen samples were taken at 0800, 1100, and 1400 h for measurement of pH and VFA concentrations. Data were analyzed using the MIXED procedure of SAS, and orthogonal linear and quadratic contrasts were used to assess phytogenic supplementation level effects. Intake and digestibility of DM and OM were not different across treatments (P ≥ 0.32). Average fecal N and lamb shrink before slaughter increased linearly (P ≤ 0.05) with increasing levels of phytogenic supplementation. Propionate and acetate:propionate decreased (P ≤ 0.05) and acetate, valerate, and pH tended to increase quadratically (P ≤ 0.08) with increasing phytogenic inclusion. Back-fat and yield grade tended (P = 0.06) to decrease linearly and dressing percentage tended (P = 0.06) to decrease quadratically with increasing phytogenic inclusion. Phytogenic supplementation increased average fecal N and improved some carcass measures, but did not affect diet digestibility.

Effect of Morning vs. Evening Turmeric Consumption on Urine Oxidative Stress Biomarkers in Obese, Middle-Aged Adults: A Feasibility Study

The circadian rhythm of biological systems is an important consideration in developing health interventions. The immune and oxidative defense systems exhibit circadian periodicity, with an anticipatory increase in activity coincident with the onset of the active period. Spice consumption is associated with enhanced oxidative defense. The objective of this study was to test the feasibility of a protocol comparing the effects of morning vs. evening consumption of turmeric on urine markers of oxidative stress in obese, middle-aged adults. Using a within-sample design, participants received each of four clock time x treatment administrations, each separated by one week: morning turmeric; evening turmeric; morning control; evening control. Participants prepared for each lab visit by consuming a low-antioxidant diet for two days and fasting for 12 h. Urine was collected in the lab at baseline and one-hour post-meal and at home for the following five hours. The results showed that the processes were successful in executing the protocol and collecting the measurements and that participants understood and adhered to the instructions. The findings also revealed that the spice treatment did not elicit the expected antioxidant effect and that the six-hour post-treatment urine collection period did not detect differences in urine endpoints across treatments. This feasibility study revealed that modifications to the spice treatment and urine sampling timeline are needed before implementing a larger study.

Acute increases of renal medullary osmolality stimulate endothelin release from the kidney

Experiments conducted in vitro suggest that high osmolality stimulates endothelin production and release by renal tubular epithelial cells. Whether hyperosmotic solutions exert similar effects in vivo is unknown. Therefore, we tested the hypothesis that increasing renal medullary osmolality enhances urinary excretion of endothelin in anesthetized rats. Isosmotic NaCl (284 mosmol/kgH2O) was infused either intravenously (1.5 ml/h) or into the renal medullary interstitium (0.5 ml/h) during a 1-h equilibration period and 30-min baseline urine collection period, followed by either isosmotic or hyperosmotic NaCl (921 or 1,664 mosmol/kgH2O iv; 1,714 mosmol/kgH2O into renal medulla) for two further 30-min periods. Compared with isosmotic NaCl, infusion of hyperosmotic NaCl into the renal medulla significantly increased the endothelin excretion rate ( P < 0.05; from 0.30 ± 0.02 to 0.49 ± 0.03 fmol/min). Intravenous infusion of hyperosmotic NaCl also significantly increased endothelin excretion rate in a concentration-dependent manner (from 0.79 ± 0.07 to 1.77 ± 0.16 fmol/min and 0.59 ± 0.04 to 1.11 ± 0.08 fmol/min for 1,664 and 921 mosmol/kgH2O, respectively). To differentiate between effects of osmolality and NaCl, similar experiments were performed using mannitol solutions. Compared with isosmotic mannitol, medullary interstitial infusion of hyperosmotic mannitol (1,820 mosmol/kgH2O) significantly increased endothelin excretion rate ( P < 0.05; from 0.54 ± 0.03 to 0.94 ± 0.12 fmol/min). Thus exposing the renal medulla to hyperosmotic concentrations of either NaCl or mannitol stimulates endothelin release in vivo, consistent with medullary osmolality being an important regulator of renal endothelin synthesis.

THE DEIODINATION OF THYROXINE IN HYPERTHYROID RATS AS DETERMINED BY RENAL CLEARANCE OF IODIDE

ABSTRACT Other investigators have reported that whole body clearance of thyroxine (T4) is increased in hyperthyroid rats isotopically equilibrated with radioactive T4, using the 24 h post-injection serum T4 concentration in the clearance calculation. Data from this laboratory indicate that serum T4 concentration is lowest at this point yielding falsely high clearance values, particularly when high doses of T4 are injected. To investigate this problem further, two types of experiments were performed. First, rats were equilibrated with [125I]T4, 5 or 20 μg/day, and the urinary clearance of iodide derived from T4 (deiodinative clearance) was measured from 0–7 and 7–24 h after a T4 injection, using the T4 concentration in serum obtained at the midpoint of each urine collection period. Urine was then collected from the ureters for several 1 h periods during the 4th to 8th h following T4 injection, calculating clearances using the midpoint plasma T4 concentration. Second, normal rats were given a single dose of [125I]T4, 5 or 55 μg/rat, and deiodinative clearance was determined during the subsequent 0–7 and 7–24 h periods. The first experiment indicated that deiodinative clearance was significantly enhanced in rats equilibrated with the large dose of T4 under all conditions studied. In contrast, the clearance in normal rats given a single large dose of T4 was not significantly different from that of normal rats given a small dose of T4. These results support the view that T4 clearance is increased in hyperthyroidism, due in part to an increase in the deiodination of T4.

ÜBER DEN EINFLUSS VON SULFONYLHARNSTOFF, ACTH UND METOPIRON AUF ENDPRODUKTE DES KATECHOLAMINSTOFFWECHSELS BEIM DIABETES MELLITUS

ABSTRACT Vanillic mandelic acid (VMA), vanillic acid (VA) and homo vanillic acid (HVA) were determined in urine (collection period: 4 hours) of 11 controls, 7 patients with latent and 8 with manifest diabetes receiving sulfonyl urea, ACTH and Metopirone. The three investigated groups showed no difference in the elimination of VMA, VA and HVA during a test-free four hours period. After the application of sulfonyl urea the VMA and VA values were lowered in the diabetic group in contrary to the control persons, whereas the elimination of HVA remained unchanged. There was no difference in the HVA values between latent diabetics and controls. VA and HVA were somewhat increased after i. v. ACTH-application, VMA remained unchanged. In the diabetic group the three catecholamine metabolites were augmented up to twofold. Similar results were found during the endogenous ACTH-mobilisation by Metopirone where the diabetics also had the highest rise in VMA, VA and HVA. On account of these experiments it must be discussed that the sympathic-adrenal system of diabetics reacts more intensive to exogenous and endogenous ACTH.