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Reduced Food Intake (reduced + food_intake)
Selected AbstractsReduced growth of rainbow trout (Oncorhynchus mykiss) fed a live invertebrate diet pre-exposed to metal-contaminated sedimentsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2004James A. Hansen Abstract Juvenile rainbow trout (Oncorhynchus mykiss) were fed live diets of Lumbriculus variegatus cultured in metal-contaminated sediments from the Clark Fork River Basin (MT, USA), an uncontaminated reference sediment, or an uncontaminated culture medium. Fish were tested in individual chambers; individual growth as well as the nutritional quality and caloric value of each trout's consumed diet were determined. Growth was measured following 14, 28, 42, 56, and 67 d of exposure. A subset of fish was sampled at 35 d for whole-body metals. Metals (whole body, digestive tract, and liver) and histology were measured at the end of the test. We observed significant growth inhibition in trout fed the contaminated diets; growth inhibition was associated with reductions in conversion of food energy to biomass rather than with reduced food intake. Growth inhibition was negatively correlated with As in trout tissue residues. Histological changes in contaminated treatments included hepatic necrosis and degenerative alterations in gallbladder. The present study provides evidence that metal-contaminated sediments can pose a hazard to trout health through a dietary exposure pathway. [source] Short-term dietary restriction and fasting precondition against ischemia reperfusion injury in miceAGING CELL, Issue 1 2010James R. Mitchell Summary Dietary restriction (DR) extends lifespan and increases resistance to multiple forms of stress, including ischemia reperfusion injury to the brain and heart in rodents. While maximal effects on lifespan require long-term restriction, the kinetics of onset of benefits against acute stress is not known. Here, we show that 2,4 weeks of 30% DR improved survival and kidney function following renal ischemia reperfusion injury in mice. Brief periods of water-only fasting were similarly effective at protecting against ischemic damage. Significant protection occurred within 1 day, persisted for several days beyond the fasting period and extended to another organ, the liver. Protection by both short-term DR and fasting correlated with improved insulin sensitivity, increased expression of markers of antioxidant defense and reduced expression of markers of inflammation and insulin/insulin-like growth factor-1 signaling. Unbiased transcriptional profiling of kidneys from mice subject to short-term DR or fasting revealed a significant enrichment of signature genes of long-term DR. These data demonstrate that brief periods of reduced food intake, including short-term daily restriction and fasting, can increase resistance to ischemia reperfusion injury in rodents and suggest a rapid onset of benefits of DR in mammals. [source] Longevity and fecundity of Eulophus pennicornis, an ectoparasitoid of the tomato moth Lacanobia oleracea, is affected by nutritional state and diet qualityAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2010Maureen E. Wakefield 1Adult female Eulophus pennicornis require a source of nutrition, provided by sources such as pollen, nectar and honeydew or by host feeding, to promote longevity and facilitate egg production. There is potential for parasitoids to be exposed directly to contaminants, including gene products in transgenic crops, through feeding on plant materials, honeydew or hosts. Among such potential contaminants are lectins such as Galanthus nivalis agglutinin (GNA) and concanavalin agglutinin (Con A). 2The effect of direct exposure to honey diets containing GNA and Con A on the longevity and fecundity of E. pennicornis was examined. These lectins have been expressed in a number of plant species for the control for various insect pests. Both GNA and Con A significantly reduced longevity and fecundity at the highest concentration used (0.5% w/v). The effect on fecundity was shown to be related to a reduction in longevity. 3Examination of the gustatory response of adult female E. pennicornis to honey diet containing 1% w/v GNA or Con A revealed no significant differences in consumption rate on first exposure. A significant reduction in the time spent feeding on diet containing 1% Con A was found on the second exposure to the diet. This could have been the result of either a conditioned aversion response or the intoxication of the insect. The effect of Con A on longevity and fecundity could have been, in part, a result of reduced food intake. 4Studies on nutrition and egg resorption demonstrated that the availability of honey solution prolongs the longevity of E. pennicornis and the lack of a source of nutrition promotes oosorption. 5A greater understanding of feeding behaviour and ovigeny is required to understand fully the potential ecological consequence of transgenic crops on parasitoid species through routes of direct exposure to transgene products. [source] Divergent Regulation of Hypothalamic Neuropeptide Y and Agouti-Related Protein by Photoperiod in F344 rats With Differential Food Intake and GrowthJOURNAL OF NEUROENDOCRINOLOGY, Issue 7 2009A. W. Ross Hypothalamic genes involved in food intake and growth regulation were studied in F344 rats in response to photoperiod. Two sub-strains were identified: F344/NHsd (F344/N) and F344/NCrHsd (F344/NCr); sensitive and relatively insensitive to photoperiod respectively. In F344/N rats, marked, but opposite, changes in the genes for neuropeptide Y (NPY) (+97.5%) and agouti-related protein (AgRP) (,39.3%) expression in the arcuate nucleus were observed in response to short (8 : 16 h light/dark cycle, SD) relative to long (16 : 8 h light/dark cycle, LD) day photoperiods. Changes were associated with both reduced food intake and growth. Expression of the genes for cocaine and amphetamine-regulated transcript (CART) and pro-opiomelanocortin (POMC) in the arcuate nucleus was unchanged by photoperiod. POMC in the ependymal layer around the third ventricle was markedly inhibited by SD. Parallel decreases in the genes for growth hormone-releasing hormone (GHRH) and somatostatin (Somatostatin) mRNA in the arcuate nucleus and Somatostatin in the periventricular nucleus were observed in SD. Serum levels of insulin-like growth factor (IGF)-1 and insulin were lower in F344/N rats in SD, whereas neither leptin nor corticosterone levels were affected. By contrast, F344/NCr rats that show only minor food intake and growth rate changes showed minimal responses in these genes and hormones. Thus, NPY/AgRP neurones may be pivotal to the photoperiodic regulation of food intake and growth. Potentially, the SD increase in NPY expression may inhibit growth by decreasing GHRH and Somatostatin expression, whereas the decrease in AgRP expression probably leads to reduced food intake. The present study reveals an atypical and divergent regulation of NPY and AgRP, which may relate to their separate roles with respect to growth and food intake, respectively. [source] Zanthoxylum piperitum (DC), a potential feeding deterrent for mammals: studies with Microtus ochrogaster (Wagner)PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 7 2004Gisela Epple Abstract Total extract from the fruit of Szechuan pepper (Zanthoxylum piperitum DC), the volatile components of the extract and a non-volatile fraction containing alkylamides (NVA fraction) are feeding deterrents for rats. The present study investigated the effectiveness of these natural repellents in prairie voles (Microtus ochrogaster Wagner). Two-choice feeding trials were conducted during which food-deprived voles were offered choices between oat-bran wafers. In Experiment 1, 10 voles were given three sets of feeding trials, each 2 h long. Baseline consumption was established during the first set of two trials by offering a choice between two oat-bran wafers dipped in ethanol, the control solvent. During the second set of two trials the voles were given a choice between an oat-bran wafer dipped in ethanol and a wafer dipped in Zanthoxylum extract. During the third set the voles were given a choice between a wafer served on top of a screened dish containing a sample of ethanol and a wafer served on top of a dish containing a sample of extract. In this manner the voles were exposed to volatile compounds emanating from the extract but could not contact it. Wafers dipped in extract were almost completely avoided. The volatile components of extract also significantly reduced food intake. In Experiment 2, habituation to the volatile constituents of extract was examined in 16 Zanthoxylum -naïve voles. Baseline consumption was established by offering two wafers served on top of screened dishes containing ethanol. This was followed by twelve tests during which a choice between a wafer served above a sample of ethanol and a wafer served above a sample of extract was given. The voles failed to habituate to the volatile components of extract, consistently consuming less of the wafers served above extract. In Experiment 3 a dose-response curve to Zanthoxylum extract was established, using 12 stimulus-naïve voles. After baseline consumption was established, the animals were given two tests each, presenting a choice between a control wafer and a wafer dipped in a dilution of extract (0.001,100 g liter,1). Only concentrations of 10 and 100 g liter,1 reduced food intake. In Experiment 4 the effects of the non-volatile fraction of extract were compared to those of whole extract. Vegetable oil was used as solvent. Eight stimulus-naïve voles were given two tests with a choice between an oil-dipped and an extract-dipped wafer. A second group of eight voles received two tests with a choice between an oil-dipped and NVA-dipped wafer. Extract-dipped wafers were avoided, but the NVA fraction had no effect on food consumption. Copyright © 2004 Society of Chemical Industry [source] Effect of ketamine anesthesia on daily food intake in Macaca mulatta and Cercopithecus aethiops,AMERICAN JOURNAL OF PRIMATOLOGY, Issue 10 2007Danielle A. Springer Abstract Ketamine hydrochloride is frequently administered to non-human primates as a means of chemical restraint. This procedure can be a frequent source of stress to monkeys at research facilities, impacting animal health, well-being and research quality. This study was designed to measure ketamine's effect on daily food intake, a parameter that reflects and influences animal well-being and directly impacts research studies. On five occasions, baseline daily food intake was compared to daily food intake occurring 24, 48, 72, 96, and 120,h after an intramuscular injection of 10,mg/kg ketamine in male African green monkeys (AGMs) (Cercopithecus aethiops) and male and female rhesus macaques (Macaca mulatta). AGMs and female rhesus macaques had significantly reduced daily food intake during the first 4 days after receiving ketamine. The AGMs continued to display significantly reduced daily food intake on the fifth day after ketamine. The male rhesus macagues showed a trend toward reduced daily food intake, greatest during the first 2 days and remaining less than baseline intake through the fifth day following ketamine. The degree of observed food intake reduction was most severe at the 24,h (mean percent intake reduction: AGMs: 57%; rhesus males: 48%; rhesus females: 40%) and 48,h time points (AGMs: 24%; rhesus males: 14%; rhesus females: 13%). A subset of the AGMs that did not receive ketamine, but observed other animals in the room receive ketamine, showed reduced food intake at 24 and 48,h after ketamine, though not to the degree associated with ketamine administration. These results indicate that ketamine anesthesia is associated with a prolonged reduction in daily food intake in AGMs and rhesus macaques. Frequent use of ketamine in non-human primates may have a significant impact on animal health and well-being, and alternatives to its use warrant consideration. Am. J. Primatol. 69:1080,1092, 2007. Published 2007 Wiley-Liss, Inc. [source] | ||||||||||