Carnitine supplementation decreases heat production in racing pigeons during flight simulation

Four groups (A,B,C,D) of nine, trained, male racing pigeons were starved for one day after two months of high energy ration intake and then subjected to a respiration chamber test. One week before, groups A and B were orally supplemented with 90 mg of L-carnitine daily, whereas C and D were given a placebo. A and C underwent flight simulation by electro-stimulation of the breast muscles. Flight simulation increased heat production, prevented a decrease in respiratory quotient due to feed deprivation, decreased T-4 plasma levels and increased weight loss. Feed deprivation caused lower plasma T-3 and T-4 levels. L-Carnitine decreased the rise in heat production during electro-stimulation but did not influence respiratory quotient, weight loss or thyroid hormones. L-Carnitine supplementation in pigeons improved efficiency of energy usage during heavy exercise, thus preventing energy losses due to anaerobic metabolism

Effect of Ca/P ratio, P level and use of phytase on ileal and fecal P digestibility in growing pigs

Eight female pigs (25-65 kg) provided with a simple T cannula about 10 cm anterior to the ileocaecal valve, were used to study the ileal, post-ileal and fecal digestibility. In experiment 1, 2 Ca/P ratios (1.5/1 and 2.2/1) and 2 dietary P levels (0.34 and 0.47%) were tested according to a 2x2-factorial arrangement within a Latin square design. In experiment 2, the diets of experiment 1 were supplemented with phytase (500 FTU/kg). Supplementation with phytase resulted in an improvement of the fecal P digestibility of 10.3% (P<0.001). Addition of feed phosphate resulted in 10.3% (P<0.001) more absorption in the ileum. Addition of limestone reduced the effects. These results indicate that P from feed phosphate is absorbed primarily ileally and that P from phytate is dominantly absorbed post-ileally