OBJECTIVE: The objective of this study was to determine whether there are independent effects of extracellular¯uid volume (ECF) and fat mass (FM) on resting energy expenditure (REE) relative to fat-free mass (FFM) in adult men and women. METHODS: Multiple linear regression analysis was used to relate REE, as determined by indirect calorimetry, to FFM and FM (measured using dual energy X-ray absorptiometry) and ECF (measured using bromide space andaor the radiosulfate washout space) in 153 women and 100 men with varying amounts of body fat. RESULTS: REE correlated signi®cantly with FFM and FM in women (r 0.65 and r 0.63, both P`0.001) and men (r 0.62 and r 0.48, both P`0.001, FFM and FM, respectively). In a multiple linear regression analysis FFM, FM and age signi®cantly contributed to the ability to predict REE in both genders. The models that were derived were not signi®cantly different between women and men. In women the contribution to REE from FM was easier to detect when FM was greater. Adjustment of FFM for ECF did not improve the relationship between FFM and REE. CONCLUSIONS: FFM, FM and age are signi®cant, independent predictors of REE in both men and women. Adjustment of FFM for ECF does not improve the ability of FFM to predict REE, which suggests that ECF is a highly integrated component of FFM in healthy adults. Expressing REE relative to FFM alone will introduce errors when lean and obese populations are compared.
The vitamin E requirement of growing pigs was estimated on the basis of prevention of morphological signs of deficiency. Five groups of pigs were fed a barley-based diet low in vitamin E that contained 16 mg of DL-alpha-tocopheryl acetate equivalents/kg and .1 ppm of Se for 4 wk (depletion I). This period was followed by 7 wk of supplementation, during which the groups received 0, 15, 45, 135 and 405 mg of supplemental DL-alpha-tocopheryl acetate/kg diet. Finally, all the animals were fed the low vitamin E diet for 7 wk (depletion II). To follow the vitamin E concentration in serum and tissues, blood samples were collected and biopsies were taken from skeletal muscle, adipose tissue and the liver throughout the experiment. The peak vitamin E value was observed in the liver, followed by the adipose tissue and then skeletal muscle. The liver responded rapidly to changes in dietary vitamin E intake, whereas the adipose tissue and the skeletal muscle reacted at a slower rate. In spite of the abundant occurrence of the different vitamin E isomers in the feed, alpha-tocopherol was the main isomer detected both in the serum and in the tissues. The activity of glutathione peroxidase in serum increased with age but was independent of the serum vitamin E concentration. In the unsupplemented group all animals suffered from the vitamin E and Se deficiency syndrome (VESD) in an acute or chronic form. A total of 31 mg of DL-alpha-tocopheryl acetate/kg diet (16 mg of naturally occurring vitamin E and 15 mg as supplementation) equivalent to 2.5 IU vitamin E/g polyunsaturated fatty acids (PUFA) was enough to prevent the development of VESD. In view of the large individual variations of vitamin E concentration in target organs, and to obtain a certain safety margin for prevention of VESD in growing pigs, a supplement of 30 mg of DL-alpha-tocopheryl acetate/kg diet is recommended.
The effect of vitamin E on the responsiveness of porcine lymphocytes to mitogens was studied. Initially, five groups of pigs were fed a diet low in vitamin E, corresponding to 16 mg of dl-atocopheryl acetate, for four weeks. This basal diet was then supplemented with various amounts of dla-tocopheryl acetate during a seven-week period, after which the graded levels of vitamin E intake were reflected in varying serum concentrations of vitamin E. The supplementation period was followed by a final seven-week period of vitamin E depletion on the basal diet.Lymphocyte stimulation tests were performed at the end of depletion period I, the supplementation period and depletion period 11.Lymphocytes obtained from pigs with a serum vitamin E level exceeding 3mgA showed an increased response to Pokeweed mitogen stimulation as compared with lymphocytes obtained from animals with lower concentrations of serum vitamin E.
Jensen, M., A Lindholm and J. Hakkarainen: The vitamin E distribution in serum, liver, adipose and muscle tissues in the pig during depletion and repletion. Acta vet. scand. 1990,31,129-136. -This study was designed to examine the storage capacity for vitamin E in liver, adipose tissue and skeletal muscle of growing pigs during a period of supplementation and of depletion. Therefore, biopsy specimens of these tissues and samples of serum were frequently taken from 7 pigs throughout the experimental period. After a 7-week period on a diet highly supplemented with vitamin E (405 mg/kg), a significant increase (p < 0.00 I) in the concentration of this vitamin was observed in all tissues sampled. The highest level (102.9±26.2 mg/kg) was observed in the liver. After 2 days of depletion the concentration of vitamin E in the liver had fallen by 80llJo, whereas the concentration in the fat and muscle remained unchanged during I week of depletion . The serum vitamin E value rose significantly (p
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