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Supplemental Levels (supplemental + level)
Selected AbstractsEffect of dietary linoleic acid concentration and vitamin E supplementation on cell desquamation and susceptibility to oxidative damage of pig jejunal mucosaJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1-2 2001C. J. López Bote Sixty Large White × Great York pigs weighing approximately 60 kg were individually fed on six experimental diets. The experiment was organized in a 3 × 2 factorial arrangement design with three different fat sources and a basal or supplemented (200 mg/kg diet) level of ,-tocopheryl acetate. All diets contained the same concentration of saturated fatty acids (15 ± 0.2 g/kg dry matter) but differed in the concentration of C18 : 2 (14 ± 0.5, 18 ± 0.4 and 21 ± 0.6 g/kg) and monounsaturated fatty acids (19 ± 0.2, 15 ± 1.2 and 10 ± 1.3 g/kg). No effect of dietary treatment was observed on weight gain and feed consumption. A histological study of the jejunal mucosa showed lower cell desquamation in groups containing a supplemental level of ,-tocopheryl acetate (p=0.080). A higher cell desquamation was found in the groups fed diets containing the higher concentration of C18 : 2 (p=0.087). We also observed an interaction effect (p < 0.001) of dietary fat source and vitamin E supplementation on jejunal cell desquamation in which the effect of dietary vitamin E was lower when diets with a low concentration of C18 : 2 were administered. In vitro- induced oxidation of jejunal mucosa homogenates was lower in pigs fed diets supplemented with ,-tocopheryl acetate (p < 0.002). The dietary concentration of C18 : 2 significantly affected oxidation of pig jejunal mucosa (p < 0.002). [source] UV-B radiation constrains the photosynthesis of Quercus robur through impacts on the abundance of Microsphaera alphitoidesFOREST PATHOLOGY, Issue 5 2000By K. K. Newsham Summary Quercus robur saplings were exposed at an outdoor facility in the UK to supplemental levels of UV-B radiation (280,315 nm) under arrays of cellulose diacetate-filtered fluorescent lamps which also produced UV-A radiation (315,400 nm). Saplings were also exposed to supplemental UV-A radiation under arrays of polyester-filtered lamps and to ambient levels of solar radiation under arrays of unenergized lamps. The UV-B treatment was modulated to maintain a 30% elevation above the ambient level of erythemally weighted UV-B radiation. Naturally occurring infections by oak powdery mildew (Microsphaera alphitoides) were more abundant, and developed more rapidly, on lammas leaves of saplings which were exposed to treatment levels of UV-B radiation than on leaves of saplings exposed to supplemental UV-A or to ambient levels of solar radiation over 12 weeks in summer and autumn 1996. An analysis of leaf photosynthetic capacities revealed that M. alphitoides infection reduced the quantum efficiency of photosystem (PS) II by 14% at moderate irradiance. Although there was no direct effect of UV-B radiation on PSII photochemistry, exposure of saplings to supplemental UV-A radiation under polyester-filtered lamps resulted in a 17.5% decrease in PSII quantum efficiency, compared with saplings exposed to ambient solar radiation. The results from our study suggest that photosynthesis of Q. robur may be constrained by exposure to UV-B radiation in the natural environment through impacts on the abundance of M. alphitoides. [source] Effects of Dietary Vitamin A on Juvenile Red Sea Bream Chrysophrys majorJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2004Luis Hector A 55-d feeding experiment was conducted to evaluate the effects of dietary vitamin A on growth of juvenile red sea bream Chrysophrys major. Nine semi-purified diets with supplemental retinol palmitate at levels of 0, 300, 600, 1,500, 3,000, 4,500, 6,000, 15,000 and 30,000 retinol eq/kg diet, were fed twice daily to triplicate groups of 10 juveniles per tank with an initial weight of 1.178 ± 0.001 g. Weight gain and specific growth rate increased with the increase of supplemental retinol palmitate in the diet up to a level of 6,000 retinol eq/kg diet, beyond which those indices tended to decrease slightly or to plateau. Significantly lower weight gain and specific growth rate were observed in fish fed with 0 and 300 retinol eq/kg diet. No significant differences were found in survival rates among the different levels of supplementation. The crude protein, lipid, moisture and ash contents in the whole body were not affected by the different vitamin A supplemental levels. Besides the reduced growth, fish fed with low levels of vitamin A supplement showed no other signs of deficiency. No hypervitaminosis A symptoms were observed in fish fed on high levels of supplementation. Fish fed on diets with 0 and 300 retinol eq/kg diet showed a significantly lower content of vitamin A (as a total retinol) in the liver than those in groups fed with higher levels of supplementation. Vitamin A was stored in the liver mainly as retinyl esters. Total retinal content of the eye showed no significant differences among the treatments; however, fish fed with 0 and 300 retinol eq/kg of diet had slightly higher concentrations. According to the results of the mean weight gain, specific growth rate and liver retinol content, the requirement of dietary vitamin A for juvenile red sea bream was estimated to be between 1,500 and 6,000 retinol eq/kg. [source] Effect of dietary pantothenic acid supplement on growth, body composition and intestinal enzyme activities of juvenile Jian carp (Cyprinus carpio var. Jian)AQUACULTURE NUTRITION, Issue 5 2009Z.-P. WEN Abstract A 9-week feeding trial was carried out with juvenile Jian carp to study the effect of dietary pantothenic acid (PA) on growth, body composition and intestinal enzyme activities. Semi-purified diets with seven levels (4.0, 15.5, 25.6, 36.1, 45.9, 56.1 and 65.9 mg PA kg,1) of supplemental calcium d -pantothenate were fed to Jian carp (13.0 ± 0.0 g). PA improved specific growth rate (SGR), protein productive value (PPV), protein efficiency ratio (PER) and lipid production value (LPV) (P < 0.05). Fish fed the control diet had significantly lower feed efficiency (FE) than that in any other group (P < 0.05). Body protein content increased with increasing PA levels (P < 0.05), but moisture, lipid and ash of fish carcasses were negatively related to the graded PA levels (P < 0.05). Intestine protein content (IPC), hepatopancreas protein content (HPC) and activity of ,-amylase, lipase, trypsin, Na+,K+ -ATPase, alkaline phosphatase (AKP) and gamma-glutamyl transpeptidase (,-GT) were all positively affected by the dietary PA levels (P < 0.05), while intestine index (ISI) and hepatopancreas index (HSI) decreased with the increment of supplemental levels of PA (P < 0.05). These results suggested that PA could enhance fish growth and intestinal enzyme activities. The dietary PA requirement of juvenile Jian carp, Cyprinus carpio var. Jian (13.0,73.0 g), for optimal growth estimated by the broken-line analysis was 23.0 mg PA kg,1 diet. [source] | |||||||||||||