The impact of different environmental salinities on the energy metabolism of gills, kidney, liver, and brain was assessed in gilthead sea bream (Sparus aurata) acclimated to brackish water [BW, 12 parts/thousand (ppt)], seawater (SW, 38 ppt) and hyper saline water (HSW, 55 ppt) for 14 days. Plasma osmolality and levels of sodium and chloride presented a clear direct relationship with environmental salinities. A general activation of energy metabolism was observed under different osmotic conditions. In liver, an enhancement of glycogenolytic and glycolytic potential was observed in fish acclimated to BW and HSW compared with those in SW. In plasma, an increased availability of glucose, lactate, and protein was observed in parallel with the increase in salinity. In gills, an increased Na ϩ -K ϩ -ATPase activity, a clear decrease in the capacity for use of exogenous glucose and the pentose phosphate pathway, as well as an increased glycolytic potential were observed in parallel with the increased salinity. In kidney, Na ϩ -K ϩ -ATPase activity and lactate levels increased in HSW, whereas the capacity for the use of exogenous glucose decreased in BW-and HSWacclimated fish compared with SW-acclimated fish. In brain, fish acclimated to BW or HSW displayed an enhancement in their potential for glycogenolysis, use of exogenous glucose, and glycolysis compared with SW-acclimated fish. Also in brain, lactate and ATP levels decreased in parallel with the increase in salinity. The data are discussed in the context of energy expenditure associated with osmotic acclimation to different environmental salinities in fish euryhaline species.Gilthead sea bream; Sparus aurata; osmoregulation; energy metabolism ADAPTATION OF EURYHALINE FISH to different environmental salinities induces changes/activation of ion transport mechanisms. This adaptation is usually accompanied by changes in oxygen consumption, suggesting variations in the energetic demands for osmoregulation. Thus five patterns of metabolic response to altered environmental salinities have been suggested by Morgan and Iwama (37) in fish, including: 1) no change in metabolic rate, 2) metabolic rate is minimum in isotonic salinity and increased at lower and higher salinities, 3) metabolic rate increases linearly with salinity, 4) metabolic rates higher in freshwater (FW) that decrease in isotonic media [do not tolerate seawater (SW)], and 5) rate highest in SW and decreasing in other salinities. These changes in oxygen consumption can lead to variations in whole body metabolism. The metabolic response of the fish to different osmotic conditions undoubtedly includes both stress and osmoregulation components, but the relative energetic demands of these processes cannot be discerned from whole animal oxygen consumption. Thus, not unexpectedly, alterations in intermediary metabolism related to osmoregulation are not fully understood in fish (41). In addition, the influence of environmental salinities on the growth rate in fish is also poorly understood (4).Although the function...

The influence of high stocking density (HSD) and food deprivation was assessed on carbohydrate metabolism of several tissues of gilthead sea bream Sparus auratus for 14 days. Fish were randomly assigned to one of four treatments: (1) fed fish under normal stocking density (NSD) (4 kg m À3 ); (2) fed fish under HSD (70 kg m À3 ); (3) food-deprived fish under NSD; and (4) fooddeprived fish under HSD. After 14 days, samples were taken from the plasma, liver, gills, kidney and brain for the assessment of plasma cortisol, levels of metabolites and the activity of several enzymes involved in carbohydrate metabolism. HSD conditions alone elicited important changes in energy metabolism of several tissues that in some cases were confirmatory (5-fold increase in plama cortisol, 20% increase in plasma glucose, 60% decrease in liver glycogen and 20% increase in gluconeogenic potential in the liver) whereas in others provided new information regarding metabolic adjustments to cope with HSD in the liver (100% increase in glucose phosphorylating capacity), gills (30% decrease in capacity for phosphorylating glucose), kidney (80% increase in the capacity of phosphorylating glucose) and brain (2.5-fold increase in ATP levels). On the other hand, food deprivation alone resulted in increased plasma cortisol, and metabolic changes in the liver (enhanced gluconeogenic and glycogenolytic potential of 13% and 18%, respectively) and brain (10% increase in glycolytic capacity), confirmatory of previous studies, whereas new information regarding metabolic adjustments during food deprivation was obtained in the gills and kidney (decreased lactate levels in both tissues of 45% and 55%, respectively). Furthermore, the results obtained provided, for the first time in fish, information indicating that food deprivation increased the sensitivity of gilthead sea bream to the stress induced by HSD compared with the fed controls, as demonstrated by increased plasma cortisol levels (50% increase vs. fed fish) and a further increase in the capacity to export glucose mobilized from liver glycogen stores (70% decrease vs. fed fish). These results lend support for a cumulative effect of both stressors on plasma cortisol and parameters assessed on carbohydrate metabolism in the present experiments, and provide information regarding reallocation of metabolic energy to cope with simultaneous stressors in fish. J. Exp. Zool. 303A:761-775, 2005. In the aquaculture environment, the exposure to stressors is commonplace due to regular management procedures (weighing, transporting, etc.) or for economic reasons that increased rearing densities (Barton and Iwama, '91;Ruane et al., 2002). Not surprisingly, most studies on the physiology of stress in fish have been directed towards the effects of common stressors related to handling procedures in laboratory work and Published online in Wiley InterScience (www.interscience.wiley. com).

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BackgroundThe Maternal-Child Pastoral is a volunteer-based community organization of the Dominican Republic that works with families to improve child survival and development. A program that promotes key practices of maternal and child care through meetings with pregnant women and home visits to promote child growth and development was designed and implemented. This study aims to evaluate the impact of the program on nutritional status indicators of children in the first two years of age.MethodsA quasi-experimental design was used, with groups paired according to a socioeconomic index, comparing eight geographical areas of intervention with eight control areas. The intervention was carried out by lay health volunteers. Mothers in the intervention areas received home visits each month and participated in a group activity held biweekly during pregnancy and monthly after birth. The primary outcomes were length and body mass index for age. Statistical analyses were based on linear and logistic regression models.Results196 children in the intervention group and 263 in the control group were evaluated. The intervention did not show statistically significant effects on length, but point estimates found were in the desired direction: mean difference 0.21 (95%CI −0.02; 0.44) for length-for-age Z-score and OR 0.50 (95%CI 0.22; 1.10) for stunting. Significant reductions of BMI-for-age Z-score (−0.31, 95%CI −0.49; -0.12) and of BMI-for-age > 85th percentile (0.43, 95%CI 0.23; 0.77) were observed. The intervention showed positive effects in some indicators of intermediary factors such as growth monitoring, health promotion activities, micronutrient supplementation, exclusive breastfeeding and complementary feeding.ConclusionsDespite finding effect measures pointing to effects in the desired direction related to malnutrition, we could only detect a reduction in the risk of overweight attributable to the intervention. The findings related to obesity prevention may be of interest in the context of the nutritional transition. Given the size of this study, the results are encouraging and we believe a larger study is warranted.

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