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Daily Food Intake (daily + food_intake)
Selected AbstractsDifferential effects of short and long duration insulinotropic agents on meal-related glucose excursionsDIABETES OBESITY & METABOLISM, Issue 2 2001C. J. De Souza SUMMARY Aim Abnormal ,-cell function, characterized as the inability of the ,-cell to mount a rapid secretory response to glucose, is a well-established pathology of type 2 diabetes mellitus. These studies were designed to demonstrate the importance of early insulin release on the control of meal-induced glucose excursions by capitalizing on the significant pharmacodynamic differences between several oral insulin secreting agents. Methods Male Sprague Dawley fitted with indwelling jugular cannulas were used to compare the pharmacodynamic profiles of nateglinide (Nateg), glipizide (Glip) and repaglinide (Repag) through frequent blood samples following the administration of these compounds via oral gavage. In similar animals which were pretrained to consume their daily food intake in two discrete 45-min meals, the effects of compound induced changes in pre-meal, meal and post-meal insulin profiles on glycaemic control were assessed through frequent blood sampling following the administration of these compounds 10 min prior to a 30-min meal. Results There were significant pharmacodynamics differences between the three oral agents tested and the time to elicit peak insulin secretory responses increased from Nateg (4 min) to Repag (10 min) to Glip (45 min). During the meal tolerance test, glibenclamide did not increase pre-meal insulin levels and glucose excursions paralleled those in the control. Conversely, the other three agents, at doses that produced hypoglycaemic responses of similar magnitude, all increased early insulin release (,AUC(-15 to 3 min) = 0.5 ± 0.01, 1.6 ± 0.4, 3.6 ± 0.0, 1.2 ± 0.1 and 1.73 ± 0.4 nmol/min, for control, Nateg at 60 and 120 mg/kg, Glip and Repag, respectively) and curbed glucose excursions during the meal at varying rates and degrees (,AUC(0,30 min) = 39 ± 6, 8 ± 7, 5 ± 7, ,,1 ± 8 and ,,3 ± 8 mmol/min for control, Nateg at 60 and 120 mg/kg, Glip and Repag, respectively). However, unlike Nateg, the longer duration of action of Repag and Glip elicited sustained post-meal relative hypoglycaemia. Conclusion These data support the impact of early and rapid insulin release in the control of prandial and post-meal glycaemia and demonstrate that a short anticipatory burst of insulin, restricted to the beginning of a meal, provides a clear metabolic advantage and prevents post-meal hypoglycaemic episodes when compared to a greater but reactive insulin exposure that follows a meal-induced increase in glucose excursion. [source] Serum insulin-like growth factor-1 concentration in pigs divergently selected for daily food intake or lean growth rateJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 4 2003N. D. Cameron Summary Divergent selection over seven generations for daily food intake (DFI) and for two lean growth rate (LGA and LGS) selection objectives in pigs produced correlated responses in serum insulin-like growth factor-1 (IGF-1) concentration. The LGA and LGS selection objectives were for lean growth, but with performance testing on ad libitum (LGA) or on restricted (LGS) feeding regimes. There were 342 animals in the study, with an average of 46 pigs in each selection line and 72 pigs in the control line. All animals were performance-tested from 30 to 90 kg on an ad libitum feeding regime. Selection on DFI increased IGF-1 at 6 weeks of age (158 versus 104 ,g/l, SED 21; control 136 ,g/l) and selection for high LGA increased IGF-1 at 30 kg liveweight (202 versus 161 ,g/l, SED 14; control 185 ,g/l). At 6 weeks of age and at 30 kg of weight, there was no response in IGF-1 with selection on LGS (128 versus 129 and 167 versus 153 ,g/l, respectively) suggesting that IGF-1 may not be a reliable physiological predictor of genetic merit for such a selection objective, which combined rate and efficiency of lean growth. IGF-1 measured immediately prior to the start of performance test may be useful in determining which animals to performance test for a lean growth selection objective, whereas IGF-1 measured at 6 weeks of age may be a useful physiological predictor of genetic merit for daily food intake during performance test. Zusammenfassung Serumkonzentrationen des insulinähnlichen Wachstumsfaktors-1 bei Schweinen, die entweder auf tägliche Futteraufnahme oder auf hohe Wachstumsrate für Magerfleischanteil selektiert wurden Die Selektion von Schweinen über sieben Generationen einerseits auf tägliche Futteraufnahme (DFI) und andererseits auf zwei Wachstumsraten für Magerfleischanteil (LGA, ad-libitum -Fütterung; LGS, rationierte Fütterung) ergab korrelierende Konzentrationen am insulinähnlichen Wachstumsfaktor (IGF-1). An der Studie waren 342 Tiere mit einer durchschnittlichen Tierzahl von 46 Schweinen pro Selektionsgruppe und 72 Schweinen als Kontrollgruppe beteiligt. Alle Tiere wurden zwischen 30 und 90 kg bei der ad-libitum Fütterung leistungsgeprüft. Die Selektion auf tägliche Futteraufnahme (DFI) erhöhte die IGF-1 Konzentrationen in der 6. Lebenswoche von 104 ,g/l auf 158 ,g/l (Kontrollgruppe 136 ,g/l) und die Selektion auf LGA bei der ad-libitum -Fütterung bei einem Lebendgewicht von 30 kg von 161 ,g/l auf 202 ,g/l (Kontrollgruppe 185 ,g/l). In der 6. Lebenswoche und bei 30 kg Lebendgewicht gab es keinen Anstieg der IGF-1 Konzentrationen in der Selektionsgruppe LGS mit rationierter Fütterung (128 ,g/l bzw. 129 ,fg/l in der 6. Lebenswoche; 167 ,g/l bzw. 153 ,g/l bei 30 kg),was darauf hinweisen könnte, dass IGF-1 wahrscheinlich kein verlässlicher, physiologischer Marker für den genetischen Erfolg für ein solches Selektionsziel, welches die Wachstumsrate und die Effizienz beim Magerfleischwachstum kombiniert, darstellt. Die direkt vor Prüfungsbeginn ermittelten IGF-1 Konzentrationen könnten bei der Auswahl der Tiere, die an einer Leistungsprüfung für die Wachstumsrate des Magerfleischanteils als Selektionsziel herangezogen werden sollten, hilfreich sein. Die IGF-1 Konzentrationen, die in der 6. Lebenswoche gemessen werden, sind wahrscheinlich ein hilfreicher physiologischer Marker für den genetischen Erfolg für DFI während einer Leistungsprüfung. [source] Comparative foraging and nutrition of horses and cattle in European wetlandsJOURNAL OF APPLIED ECOLOGY, Issue 1 2002Catherine Menard Summary 1Equids are generalist herbivores that co-exist with bovids of similar body size in many ecosystems. There are two major hypotheses to explain their co-existence, but few comparative data are available to test them. The first postulates that the very different functioning of their digestive tracts leads to fundamentally different patterns of use of grasses of different fibre contents. The second postulates resource partitioning through the use of different plant species. As domestic horses and cattle are used widely in Europe for the management of conservation areas, particularly in wetlands, a good knowledge of their foraging behaviour and comparative nutrition is necessary. 2In this paper we describe resource-use by horses and cattle in complementary studies in two French wetlands. Horses used marshes intensively during the warmer seasons; both species used grasslands intensively throughout the year; cattle used forbs and shrubs much more than horses. Niche breadth was similar and overlap was high (Kulczinski's index 0·58,0·77). Horses spent much more time feeding on short grass than cattle. These results from the two sites indicate strong potential for competition. 3Comparative daily food intake, measured in the field during this study for the first time, was 63% higher in horses (144 gDM kg W,0·75 day,1) than in cattle (88 gDM kg W,0·75 day,1). Digestibility of the cattle diets was a little higher, but daily intake of digestible dry matter (i.e. nutrient extraction) in all seasons was considerably higher in horses (78 gDM kg W,0·75 day,1) than in cattle (51 gDM kg W,0·75 day,1). When food is limiting, horses should outcompete cattle in habitats dominated by grasses because their functional response is steeper; under these circumstances cattle will require an ecological refuge for survival during winter, woodland or shrubland with abundant dicotyledons. 4Horses are a good tool for plant management because they remove more vegetation per unit body weight than cattle, and use the most productive plant communities and plant species (especially graminoids) to a greater extent. They feed closer to the ground, and maintain a mosaic of patches of short and tall grass that contributes to structural diversity at this scale. Cattle use broadleaved plants to a greater extent than horses, and can reduce the rate of encroachment by certain woody species. [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] Gene expression in arcuate nucleus-median eminence of rats treated with leptin or ciliary neurotrophic factorBIOFACTORS, Issue 2 2007Suresh Ambati Abstract Ciliary neurotrophic factor (CNTF) and leptin are cytokine-like hormones and act on their corresponding receptors in the hypothalamic arcuate nucleus (ARC). The present study was designed to assess effects of intracerebroventricular (ICV) injection of leptin and CNTF on gene expression in micropunched hypothalamic arcuate nucleus-median eminence (ARCME) complex samples from rats. Male Sprague Dawley rats were implanted with lateral cerebroventricular cannulas for administration of control, 10 ,g/d leptin or 5 ,g/d CNTF for four days. Real-time Taqman RT-PCR was used to quantitatively compare the mRNA levels of selected genes in the ARC-ME complex. Leptin and CNTF increased ARC-ME mRNA levels of signal transducer and activator of transcription 3 (STAT3) by 64.5 and 124.7% (p < 0.01), suppressor of cytokine signaling 3 (SOCS3) by 258.9 and 1063.9% (p < 0.01), cocaine and amphetamine regulated transcript (CART) by 102.7 and 123.1% (p < 0.01), and proopiomelanocortin (POMC2) by 374.1 and 264.9% (p < 0.01), respectively. Leptin increased growth hormone releasing hormone (GHRH) by 309.9% (p < 0.01), while CNTF increased janus kinase 2 (JAK2) mRNA by 31.7% (p < 0.01) and decreased gonadotropin releasing hormone 1 (GNRH1) by 59.7% (p < 0.01), mitogen activated protein kinase 1 (MAPK1) by 19.4% (p < 0.05) and tyrosine hydroxylase (TH) by 74.5% (p < 0.05). Significant reduction in daily food intake and body weights by both the treatments was observed. Also, decrease in weights of fat pads was concomitant with lowered serum insulin and leptin levels. Our findings show that leptin and CNTF engage both convergent and divergent pathways involved in feeding, cellular signaling, inflammation, and other related regulatory systems. [source] Beneficial effect of laserpitin, a coumarin compound from Angelica keiskei, on lipid metabolism in stroke-prone spontaneously hypertensive ratsCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 12 2005Hiroshi Ogawa Summary 1.,Recently, we found that 4-hydroxyderricin, one of the major chalcones in Angelica keiskei extract (an ethyl acetate extract from the yellow liquid of stems), suppressed increases in systolic blood pressure and reduced both serum very low-density lipoprotein levels and liver triglyceride content in stroke-prone spontaneously hypertensive rats (SHRSP). In the present study, we have isolated laserpitin, a characteristic coumarin, from the A. keiskei extract and examined the effect of dietary laserpitin on blood pressure and lipid metabolism in SHRSP. 2.,Six-week-old male SHRSP were fed diets containing 0.1% laserpitin for 7 weeks with free access to the diet and water. Bodyweight gain was reduced by dietary laserpitin after 4 weeks through to 7 weeks without any significant change in daily food intake. Serum total cholesterol, phospholipid and apolipoprotein (apo) E levels were significantly increased, which was due to significant increases in cholesterol, phospholipid and apoE contents in the low- and high-density lipoprotein (LDL and HDL, respectively) fractions. These results suggest that dietary laserpitin increases serum apoE-HDL levels. 3.,In the liver, significant decreases in relative liver weight and triglyceride content were found after treatment with laserpitin for 7 weeks. 4.,An investigation of hepatic mRNA expression of proteins involved in lipid metabolism indicated that a significant decrease in hepatic triglyceride lipase may be responsible for the increase in serum HDL levels and also indicated that a marked decrease in adipocyte determination and differentiation factor 1 may be responsible, at least in part, for the decrease in hepatic triglyceride content. 5.,In conclusion, dietary laserpitin produces increases in serum HDL levels, especially apoE-HDL, and decreases in the hepatic triglyceride content in SHRSP. [source] | |||||||||||||