The Experts below are selected from a list of 1554 Experts worldwide ranked by ideXlab platform
Timothy J. Bartness - One of the best experts on this subject based on the ideXlab platform.
-
INGESTIVE BEHAVIORS IN SIBERIAN HAMSTERS (PHODOPUS SUNGORUS) by
2014Co-Authors: Hamsters Sungorus, Megan J Dailey, Under Direction, Timothy J. BartnessAbstract:During the past few decades, obesity has risen significantly in the United States with recent estimates showing that 65 % of Americans are overweight and 30 % are obese. This increase is a major cause for concern because obesity is linked to many secondary health consequences that include type II diabetes, heart disease, and cancer. Current approaches to the obesity problem primarily have focused on controls of Food intake and have been largely unsuccessful. Food, however, almost always has to be acquired (foraging) and frequently is stored for later consumption (Hoarding). Therefore, a more comprehensive approach that includes studying the underlying mechanisms in human foraging and Food Hoarding behaviors could provide an additional target for pharmaceutical or behavioral manipulations in the treatment and possibly prevention of obesity. Neuropeptide Y (NPY) is a particular peptide that provides a potent orexigenic drive to alter foraging, Food Hoarding (appetitive ingestive behaviors) and Food intake (consummatoryingestive behaviors) in variety of species. NPY is predominantly produced in the arcuate nucleus of the hypothalamus (ARC) and has extensive efferent projections throughout the brain. Two target nuclei of ARC-NPY, the paraventricular nucleus of the hypothalamus (PVH) an
-
pyy 3 36 into the arcuate nucleus inhibits Food deprivation induced increases in Food Hoarding and intake
Peptides, 2013Co-Authors: Brett J W Teubner, Timothy J. BartnessAbstract:Central administration of neuropeptide Y (NPY) increases Food intake in laboratory rats and mice, as well as Food foraging and Hoarding in Siberian hamsters. The NPY-Y1 and Y5 receptors (Rs) within the hypothalamus appear sufficient to account for these increases in ingestive behaviors. Stimulation of NPY-Y2Rs in the Arcuate nucleus (Arc) has an anorexigenic effect as shown by central or peripheral administration of its natural ligand peptide YY (3-36) and pharmacological NPY-Y2R antagonism by BIIE0246 increases Food intake. Both effects on Food intake by NPY-Y2R agonism and antagonism are relatively short-lived lasting ∼4h. The role of NPY-Y2Rs in appetitive ingestive behaviors (Food foraging/Hoarding) is untested, however. Therefore, Siberians hamsters, a natural Food hoarder, were housed in a semi-natural burrow/foraging system that had (a) foraging requirement (10 revolutions/pellet), no free Food (true foraging group), (b) no running wheel access, free Food (general malaise control) or (c) running wheel access, free Food (exercise control). We microinjected BIIE0246 (antagonist) and PYY(3-36) (agonist) into the Arc to test the role of NPY-Y2Rs there on ingestive behaviors. Food foraging, Hoarding, and intake were not affected by Arc BIIE0246 microinjection in fed hamsters 1, 2, 4, and 24h post injection. Stimulation of NPY-Y2Rs by PYY(3-36) inhibited Food intake at 0-1 and 1-2h and Food Hoarding at 1-2h without causing general malaise or affecting foraging. Collectively, these results implicate a sufficiency, but not necessity, of the Arc NPY-Y2R in the inhibition of Food intake and Food Hoarding by Siberian hamsters.
-
anti ghrelin spiegelmer inhibits exogenous ghrelin induced increases in Food intake Hoarding and neural activation but not Food deprivation induced increases
American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2013Co-Authors: Brett J W Teubner, Timothy J. BartnessAbstract:Circulating concentrations of the stomach-derived “hunger-peptide” ghrelin increase in direct proportion to the time since the last meal. Exogenous ghrelin also increases Food intake in rodents and humans, suggesting ghrelin may increase post-fast ingestive behaviors. Food intake after Food deprivation is increased by laboratory rats and mice, but not by humans (despite dogma to the contrary) or by Siberian hamsters; instead, humans and Siberian hamsters increase Food Hoarding, suggesting the latter as a model of fasting-induced changes in human ingestive behavior. Exogenous ghrelin markedly increases Food Hoarding by ad libitum-fed Siberian hamsters similarly to that after Food deprivation, indicating sufficiency. Here, we tested the necessity of ghrelin to increase Food foraging, Food Hoarding, and Food intake, and neural activation [c-Fos immunoreactivity (c-Fos-ir)] using anti-ghrelin Spiegelmer NOX-B11–2 (SPM), an l-oligonucleotide that specifically binds active ghrelin, inhibiting peptide-receptor interaction. SPM blocked exogenous ghrelin-induced increases in Food Hoarding the first 2 days after injection, and foraging and Food intake at 1–2 h and 2–4 h, respectively, and inhibited hypothalamic c-Fos-ir. SPM given every 24 h across 48-h Food deprivation inconsistently inhibited Food Hoarding after refeeding and c-Fos-ir, similarly to inabilities to do so in laboratory rats and mice. These results suggest that ghrelin may not be necessary for Food deprivation-induced foraging and Hoarding and neural activation. A possible compensatory response, however, may underlie these findings because SPM treatment led to marked increases in circulating ghrelin concentrations. Collectively, these results show that SPM can block exogenous ghrelin-induced ingestive behaviors, but the necessity of ghrelin for Food deprivation-induced ingestive behaviors remains unclear.
-
neural and hormonal control of Food Hoarding
American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2011Co-Authors: Timothy J. Bartness, Megan J Dailey, Erin Keenrhinehart, Brett J W TeubnerAbstract:Many animals hoard Food, including humans, but despite its pervasiveness, little is known about the physiological mechanisms underlying this appetitive behavior. We summarize studies of Food Hoarding in humans and rodents with an emphasis on mechanistic laboratory studies of species where this behavior importantly impacts their energy balance (hamsters), but include laboratory rat studies although their wild counterparts do not hoard Food. The photoperiod and cold can affect Food Hoarding, but Food availability is the most significant environmental factor affecting Food Hoarding. Food-deprived/restricted hamsters and humans exhibit large increases in Food Hoarding compared with their fed counterparts, both doing so without overeating. Some of the peripheral and central peptides involved in Food intake also affect Food Hoarding, although many have not been tested. Ad libitum-fed hamsters given systemic injections of ghrelin, the peripheral orexigenic hormone that increases with fasting, mimics Food deprivation-induced increases in Food Hoarding. Neuropeptide Y or agouti-related protein, brain peptides stimulated by ghrelin, given centrally to ad libitum-fed hamsters, duplicates the early and prolonged postFood deprivation increases in Food Hoarding, whereas central melanocortin receptor agonism tends to inhibit Food deprivation and ghrelin stimulation of Hoarding. Central or peripheral leptin injection or peripheral cholecystokinin-33, known satiety peptides, inhibit Food Hoarding. Food Hoarding markedly increases with pregnancy and lactation. Because fasted and/or obese humans hoard more Food in general, and more high-density/high-fat Foods specifically, than nonfasted and/or nonobese humans, understanding the mechanisms underlying Food Hoarding could provide another target for behavioral/pharmacological approaches to curb obesity.
-
arcuate nucleus destruction does not block Food deprivation induced increases in Food foraging and Hoarding
Brain Research, 2010Co-Authors: Megan J Dailey, Timothy J. BartnessAbstract:The mechanisms underlying the control of Food intake are considerably better understood than those underlying the appetitive ingestive behaviors of foraging and Hoarding of Food, despite the prevalence of the latter across species including humans. Neuropeptide Y (NPY) and Agouti-related protein (AgRP), two orexigenic neuropeptides known to stimulate Food intake in a variety of species, applied centrally to Siberian hamsters increases foraging and especially Hoarding with lesser increases in Food intake. Both are expressed in the arcuate nucleus (Arc) and their synthesis increases with Food deprivation, a naturally-occurring stimulus that markedly increases foraging and Hoarding in Siberian hamsters. Therefore, we tested whether destruction of Arc neurons blocks these ingestive behaviors. This was accomplished either by microinjecting NPY conjugated to saporin (NPY-SAP) bilaterally into the Arc to kill NPY receptor-bearing neurons or via neonatal monosodium glutamate (MSG) treatment. For both methods, Arc cresyl violet staining (cell density) and NPY and Y1 receptor-immunoreactivity (ir) were significantly decreased. Although baseline foraging and Food Hoarding were not affected, Food deprivation-induced increased Food Hoarding was surprisingly exaggerated approximately 100% with both types of Arc destruction. We found a substantial amount of remaining NPY-ir fibers, likely emanating from the brainstem, and a significant up-regulation of Y1 receptors in Arc NPY projections areas (hypothalamic paraventricular nucleus and perifornical area) after Arc denervation and their activation may have accounted for the exaggerated increases. The converging evidence from both Arc destruction methods suggests an intact Arc is not necessary for Food deprivation-induced increases in Food foraging and Hoarding.
Erin Keenrhinehart - One of the best experts on this subject based on the ideXlab platform.
-
neural and hormonal control of Food Hoarding
American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2011Co-Authors: Timothy J. Bartness, Megan J Dailey, Erin Keenrhinehart, Brett J W TeubnerAbstract:Many animals hoard Food, including humans, but despite its pervasiveness, little is known about the physiological mechanisms underlying this appetitive behavior. We summarize studies of Food Hoarding in humans and rodents with an emphasis on mechanistic laboratory studies of species where this behavior importantly impacts their energy balance (hamsters), but include laboratory rat studies although their wild counterparts do not hoard Food. The photoperiod and cold can affect Food Hoarding, but Food availability is the most significant environmental factor affecting Food Hoarding. Food-deprived/restricted hamsters and humans exhibit large increases in Food Hoarding compared with their fed counterparts, both doing so without overeating. Some of the peripheral and central peptides involved in Food intake also affect Food Hoarding, although many have not been tested. Ad libitum-fed hamsters given systemic injections of ghrelin, the peripheral orexigenic hormone that increases with fasting, mimics Food deprivation-induced increases in Food Hoarding. Neuropeptide Y or agouti-related protein, brain peptides stimulated by ghrelin, given centrally to ad libitum-fed hamsters, duplicates the early and prolonged postFood deprivation increases in Food Hoarding, whereas central melanocortin receptor agonism tends to inhibit Food deprivation and ghrelin stimulation of Hoarding. Central or peripheral leptin injection or peripheral cholecystokinin-33, known satiety peptides, inhibit Food Hoarding. Food Hoarding markedly increases with pregnancy and lactation. Because fasted and/or obese humans hoard more Food in general, and more high-density/high-fat Foods specifically, than nonfasted and/or nonobese humans, understanding the mechanisms underlying Food Hoarding could provide another target for behavioral/pharmacological approaches to curb obesity.
-
physiological mechanisms for Food Hoarding motivation in animals
Philosophical Transactions of the Royal Society B, 2010Co-Authors: Erin Keenrhinehart, Megan J Dailey, Timothy J. BartnessAbstract:The study of ingestive behaviour has an extensive history, starting as early as 1918 when Wallace Craig, an animal behaviourist, coined the terms ‘appetitive’ and ‘consummatory’ for the two-part sequence of eating, drinking and sexual behaviours. Since then, most ingestive behaviour research has focused on the neuroendocrine control of Food ingestion (consummatory behaviour). The quantity of Food eaten, however, is also influenced by the drive both to acquire and to store Food (appetitive behaviour). For example, hamster species have a natural proclivity to hoard Food and preferentially alter appetitive ingestive behaviours in response to environmental changes and/or metabolic hormones and neuropeptides, whereas other species would instead primarily increase their Food intake. Therefore, with the strong appetitive component to their ingestive behaviour that is relatively separate from their consummatory behaviour, they seem an ideal model for elucidating the neuroendocrine mechanisms underlying the control of Food Hoarding and foraging. This review focuses on the appetitive side of ingestive behaviour, in particular Food Hoarding, attempting to integrate what is known about the neuroendocrine mechanisms regulating this relatively poorly studied behaviour. An hypothesis is formed stating that the direction of ‘energy flux’ is a unifying factor for the control of Food Hoarding.
-
leptin inhibits Food deprivation induced increases in Food intake and Food Hoarding
American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2008Co-Authors: Erin Keenrhinehart, Timothy J. BartnessAbstract:Food deprivation stimulates foraging and Hoarding and to a much lesser extent, Food intake in Siberian hamsters. Leptin, the anorexigenic hormone secreted primarily from adipocytes, may act in the periphery, the brain, or both to inhibit these ingestive behaviors. Therefore, we tested whether leptin given either intracerebroventricularly or intraperitoneally, would block Food deprivation-induced increases in Food Hoarding, foraging, and intake in animals with differing foraging requirements. Hamsters were trained in a running wheel-based Food delivery foraging system coupled with simulated burrow housing. We determined the effects of Food deprivation and several peripheral doses of leptin on plasma leptin concentrations. Hamsters were then Food deprived for 48 h and given leptin (0, 10, 40, or 80 μg ip), and additional hamsters were Food deprived for 48 h and given leptin (0, 1.25, 2.5, or 5.0 μg icv). Foraging, Food intake, and Hoarding were measured postinjection. Food deprivation stimulated Food Hoarding to a greater degree and duration than Food intake. In animals with a foraging requirement, intracerebroventricular leptin almost completely blocked Food deprivation-induced increased Food Hoarding and intake, but increased foraging. Peripheral leptin treatment was most effective in a sedentary control group, completely inhibiting Food deprivation-induced increased Food Hoarding and intake at the two highest doses, and did not affect foraging at any dose. Thus, the ability of leptin to inhibit Food deprivation-induced increases in ingestive behaviors differs based on foraging effort (energy expenditure) and the route of administration of leptin administration.
-
mtii attenuates ghrelin and Food deprivation induced increases in Food Hoarding and Food intake
Hormones and Behavior, 2007Co-Authors: Erin Keenrhinehart, Timothy J. BartnessAbstract:Food deprivation triggers a constellation of physiological and behavioral changes including increases in peripherally-produced ghrelin and centrally-produced agouti-related protein (AgRP). Upon refeeding, Food intake is increased in most species, however hamsters primarily increase Food Hoarding. Food deprivation-induced increases in Food Hoarding by Siberian hamsters are mimicked by peripheral ghrelin and central AgRP injections. Because Food deprivation stimulates ghrelin as well as AgRP synthesis/release, Food deprivation-induced increases in Hoarding may be mediated by melanocortin 3 or 4 receptor (MC3/4-R) antagonism via AgRP, the MC3/4-R inverse agonist. Therefore, we asked: Can a MC3/4-R agonist block Food deprivation- or ghrelin-induced increases in foraging, Food Hoarding and Food intake? This was accomplished by injecting melanotan II (MTII), a synthetic MC3/4-R agonist, into the 3rd ventricle in Food deprived, fed or peripheral ghrelin injected hamsters and housed in a running wheel-based Food delivery foraging system. Three foraging conditions were used: a) no running wheel access, non-contingent Food, b) running wheel access, non-contingent Food or c) a foraging requirement for Food (10 revolutions/pellet). Food deprivation was a more potent stimulator of foraging and Hoarding than ghrelin. Concurrent injections of MTII completely blocked Food deprivation- and ghrelin-induced increases in Food intake and attenuated, but did not always completely block, Food deprivation- and ghrelin-induced increases in Food Hoarding. Collectively, these data suggest that the MC3/4-R are involved in ghrelin- and Food deprivation-induced increases in Food intake, but other neurochemical systems, such as previously demonstrated with neuropeptide Y, also are involved in increases in Food Hoarding as well as foraging.
-
npy y1 receptor is involved in ghrelin and fasting induced increases in foraging Food Hoarding and Food intake
American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2007Co-Authors: Erin Keenrhinehart, Timothy J. BartnessAbstract:Fasting triggers a constellation of physiological and behavioral changes, including increases in peripherally produced ghrelin and centrally produced hypothalamic neuropeptide Y (NPY). Refeeding stimulates Food intake in most species; however, hamsters primarily increase foraging and Food Hoarding with smaller increases in Food intake. Fasting-induced increases in foraging and Food Hoarding in Siberian hamsters are mimicked by peripheral ghrelin, central NPY, and NPY Y1 receptor agonist injections. Because fasting stimulates ghrelin and subsequently NPY synthesis/release, it may be that fasting-induced increased Hoarding is mediated by NPY Y1 receptor activation. Therefore, we asked: Can an Y1 receptor antagonist block fasting- or ghrelin-induced increases in foraging, Food Hoarding, and Food intake? This was accomplished by injecting the NPY Y1 receptor antagonist 1229U91 intracerebroventricularly in hamsters fasted, fed, or given peripheral ghrelin injections and housed in a running wheel-based Food delivery foraging system coupled with simulated-burrow housing. Three foraging conditions were used: 1) no running wheel access, free Food, 2) running wheel access, free Food, or 3) foraging requirement (10 revolutions/pellet) for Food. Fasting was a more potent stimulator of foraging and Food Hoarding than ghrelin. Concurrent injections of 1229U91 completely blocked fasting- and ghrelin-induced increased foraging and Food intake and attenuated, but did not always completely block, fasting- and ghrelin-induced increases in Food Hoarding. Collectively, these data suggest that the NPY Y1 receptor is important for the effects of ghrelin- and fasting-induced increases in foraging and Food intake, but other NPY receptors and/or other neurochemical systems are involved in increases in Food Hoarding.
Dehua Wang - One of the best experts on this subject based on the ideXlab platform.
-
gnrh expression and cell proliferation are associated with seasonal breeding and Food Hoarding in mongolian gerbils meriones unguiculatus
Hormones and Behavior, 2019Co-Authors: Wei Yao, Dehua Wang, Zuoxin Wang, Wei Liu, Ke Deng, Xueying ZhangAbstract:Seasonal brain plasticity contributes to a variety of physiological and behavioral processes. We hypothesized that variations in GnRH expression and cell proliferation facilitated seasonal breeding and Food Hoarding. Here, we reported seasonal changes in sexual and social behavior, GnRH expression and brain cell proliferation, and the role of photoperiod in inducing seasonal breeding and brain plasticity in Mongolian gerbils (Meriones unguiculatus). The gerbils captured in April and July had more mature sexual development, higher exploratory behavior, and preferred novelty much more than those captured in September. Male gerbils captured in April and July had consistently higher GnRH expression than those captured in September. GnRH expression was also found to be suppressed by Food-induced Hoarding behavior in the breeding season. Both subadult and adult gerbils from April and July had higher cell proliferation in SVZ, hypothalamus and amygdala compared to those in September. However, adult gerbils captured in September preferred familiar objects, and no seasonal differences were found in cell proliferation in hippocampal dentate gyrus among the three seasons. The laboratory study showed that photoperiod alone did not alter reproductive traits, behavior, cell proliferation or cell survival in the detected brain regions. These findings suggest that the structural variations in GnRH expression in hypothalamus and cell proliferation in hypothalamus, amygdala and hippocampus are associated with seasonal breeding and Food Hoarding in gerbils. It gives a new insight into the proximate physiological and neural basis for these seasonal life-history traits of breeding and Food Hoarding in small mammals.
-
Food Hoarding but not Food intake is attenuated by acute diazepam treatment in female mongolian gerbils meriones unguiculatus
Hormones and Behavior, 2014Co-Authors: Huidi Yang, Qian Wang, Dehua WangAbstract:This article is part of a Special Issue "Energy Balance". Effects of γ-aminobutyric acid (GABA) on Food Hoarding are unknown in rodents, and the effects of energy balance and GABA have not been evaluated in females. To evaluate the role of Food deprivation and GABA on Food Hoarding, female Mongolian gerbils were given i.p. injection of diazepam (1mg/kg and 3mg/kg, respectively), a GABAA receptor agonist. Among Food-deprived females, there was a bimodal pattern in the frequency of gerbils with different levels of Food Hoarding. High Food Hoarding (HFH) and low Food Hoarding (LFH) gerbils were analyzed. Diazepam blocked Food deprivation-induced Food Hoarding in HFH gerbils, but not in LFH gerbils. This blockade was associated with increased cellular activation in selected brain areas, such as the nucleus accumbens (NAcc), caudate putamen (CP) and ventral tegmental area (VTA), which suggested that direct activation of GABA in the brain reward circuitry decreased Food Hoarding in HFH females. Moreover, diazepam increased Fos expression in field CA2 and CA3 of the hippocampus, but had no significant effect on Fos expression in field CA1 and dentate gyrus (DG) of the hippocampus, indicating that the hippocampus has area-specific effects on Food Hoarding in HFH gerbils. Diazepam did not alter Food intake in both HFH and LFH gerbils. In addition, serum corticosterone concentrations were higher in the HFH than in the LFH ones. Together, these data indicated that Food deprivation increased Food Hoarding in female gerbils, diazepam reduced Food deprivation-induced Food Hoarding in HFH gerbils, and that GABA might influence Food Hoarding via classical reward circuitry via the mesolimbic dopamine system and specific hippocampal areas.
-
Double-labeled cells for TH-ir and Fos-ir staining.
2013Co-Authors: Xueying Zhang, Huidi Yang, Zuoxin Wang, Qiang Zhang, Dehua WangAbstract:Photomicrographs of double-labeled cells for TH-ir (brown cytoplasmic staining) and Fos-ir (dark nuclear staining) were shown in the paraventricular nucleus (PVN; panel A), anterior hypothalamus (AH; panel B), arcuate nucleus (ARC; panel C), and ventral tegmental area (VTA; panel D) in the brain of male Brandt's voles. 3 V, third ventricle; OT, optic tract; MM, medial mammillary nucleus. Scale bar = 100 µm in panel A (applies to A–D); 10 µm in inset to panel A (applies to insets to A–D). Panel E: No group differences were found in the number of TH-ir cells in any brain areas examined in male voles that were intact controls, Food-deprived for 48 hr (FD), or re-fed for 2 hr following FD (RF2h). Panel F: RF2h males had a higher percentage of TH-ir cells that co-labeled for Fos-ir in the PVN and VTA than did the control and FD males. Panel G: Under the Food Hoarding condition, control males and males that experienced 2 hr Food Hoarding following FD (RH2h) showed no differences in the number of TH-ir cells in any of the brain regions examined. Panel H: RH2h males, however, had a higher percentage of TH-ir cells co-labeled for Fos-ir in the PVN, MPOA (medial preoptic area), ARC, and VTA than control males. No difference was found in the AH. Data are presented as mean ± SEM. * P
-
increased feeding and Food Hoarding following Food deprivation are associated with activation of dopamine and orexin neurons in male brandt s voles
PLOS ONE, 2011Co-Authors: Xueying Zhang, Huidi Yang, Zuoxin Wang, Qiang Zhang, Dehua WangAbstract:Small mammals usually face energetic challenges, such as Food shortage, in the field. They have thus evolved species-specific adaptive strategies for survival and reproductive success. In the present study, we examined male Brandt's voles (Lasiopodomys brandtii) for their physiological, behavioral, and neuronal responses to Food deprivation (FD) and subsequent re-feeding. Although 48 hr FD induced a decrease in body weight and the resting metabolic rate (RMR), such decreases did not reach statistical significance when compared to the control males that did not experience FD. During the first 2 hr of re-feeding following 48 hr FD, voles showed higher levels of feeding than controls. However, when permitted to hoard Food, FD voles showed an increase in Food Hoarding, rather than feeding, compared to the controls. Further, both feeding and Food Hoarding induced an increase in neuronal activation, measured by Fos-ir, in a large number of brain areas examined. Interestingly, feeding and Food Hoarding also induced an increase in the percentage of tyrosine hydroxylase immunoreactive (TH-ir) cells that co-expressed Fos-ir in the ventral tegmental area (VTA), whereas both FD and feeding induced an increase in the percentage of orexin-ir cells that co-expressed Fos-ir in the lateral hypothalamus (LH). Food Hoarding also increased orexin-ir/Fos-ir labeling in the LH. Together, our data indicate that Food-deprived male Brandt's voles display enhanced feeding or Food Hoarding dependent upon an environmental setting. In addition, changes in central dopamine and orexin activities in selected brain areas are associated with feeding and Hoarding behaviors following FD and subsequent re-feeding.
-
Food Hoarding and associated neuronal activation in brain reward circuitry in mongolian gerbils
Physiology & Behavior, 2011Co-Authors: Huidi Yang, Qian Wang, Zuoxin Wang, Dehua WangAbstract:Mongolian gerbils (Meriones unguiculatus) display Food Hoarding and thus provide an opportunity to study the neuromechanisms underlying this behavior. In the present study, male gerbils exhibited a bimodal expression of Food Hoarding behavior-some displayed high levels of Food Hoarding whereas others virtually lacked this behavior under normal laboratory conditions with free access to Food. Food Hoarding was found to be associated with an increase in neuronal activation, indicated by Fos immunoreactive (ir) staining, in several brain areas including the nucleus accumbens, ventral tegmental area (VTA), and lateral hypothalamus. Food Hoarding was also associated with increases in the number of cells labeled for tyrosine hydroxylase (TH-ir), the rate limiting enzyme for dopamine conversion, and the number of cells co-labeled for TH-ir/Fos-ir in the VTA, suggesting that dopamine in the brain reward circuitry may be involved in Food Hoarding. Further, we found that 22 h of Food deprivation induced Food Hoarding in some, but not all, males that naturally did not display Food Hoarding. In these males, however, Food Hoarding did not increase TH-ir or TH-ir/Fos-ir expression in the VTA. Together, these data indicate that male Mongolian gerbils display diverse phenotypes of Food Hoarding behavior and that dopamine in the brain reward circuitry may be involved in the control of naturally occurring, but not Food deprivation-induced, Food Hoarding.
K. C. Burns - One of the best experts on this subject based on the ideXlab platform.
-
memory for multiple cache locations and prey quantities in a Food Hoarding songbird
Frontiers in Psychology, 2012Co-Authors: Nicola Armstrong, Alexis Garland, K. C. BurnsAbstract:Most animals can discriminate between pairs of numbers that are each less than four without training. However, North Island robins (Petroica longipes), a Food Hoarding songbird endemic to New Zealand, can discriminate between quantities of items as high as eight without training. Here we investigate whether robins are capable of other complex quantity discrimination tasks. We test whether their ability to discriminate between small quantities declines with 1. the number of cache sites containing prey rewards and 2. the length of time separating cache creation and retrieval (retention interval). Results showed that subjects generally performed above chance expectations. They were equally able to discriminate between different combinations of prey quantities that were hidden from view in 2, 3 and 4 cache sites from between 1, 10 and 60 seconds. Overall results indicate that North Island robins can process complex quantity information involving more than two discrete quantities of items for up to one minute long retention intervals without training.
-
Fine-scale Food Hoarding decisions in New Zealand Robins (Petroica australis): is inter-sexual competition important?
Journal of Ornithology, 2009Co-Authors: K. C. BurnsAbstract:Competition for cache retrieval is hypothesised to influence Food Hoarding intensity. Previous work has tested this hypothesis by evaluating Food Hoarding rates during foraging bouts when animals are exposed to different levels of competition for cache retrieval. Little is known about how competition might influence fine-scale Food Hoarding decisions within foraging bouts. I evaluated fine-scale Food Hoarding decisions of New Zealand Robins ( Petroica australis ) by offering mealworms to competitively dominant males and subordinate females, both when they were alone and when they foraged together. I then compared Food Hoarding rates of sequentially handled prey between sexes and social conditions by assessing how the total number of prey cached increased with the total number of prey handled. Relationships for solitary females, solitary males and paired males were non-linear, indicating that they were more likely to consume initially handled prey, and increasingly likely to cache subsequently handled prey items. Non-linear rates of Food Hoarding may result from declines in the energetic value of prey that are consumed and stored internally as birds become satiated. Somewhat differently, the relationship for paired females was linear, indicating that paired females make a single Food Hoarding decision based on bout-level foraging conditions, which results in constant fine-scale Food Hoarding rates. Constant Food Hoarding rates in paired females, which experience the strongest competitive effects of any treatment, suggest that Food consumption is consistently more advantageous than Food Hoarding under these conditions, regardless of satiation level. Overall results from this study indicate that New Zealand Robins continuously update Food Hoarding decisions according to their competitive environment and satiation levels, resulting in scale-dependent patterns in Food Hoarding intensity.
-
adaptive numerical competency in a Food Hoarding songbird
Proceedings of The Royal Society B: Biological Sciences, 2008Co-Authors: Simon Hunt, Jason Low, K. C. BurnsAbstract:Most animals can distinguish between small quantities (less than four) innately. Many animals can also distinguish between larger quantities after extensive training. However, the adaptive significance of numerical discriminations in wild animals is almost completely unknown. We conducted a series of experiments to test whether a Food-Hoarding songbird, the New Zealand robin Petroica australis , uses numerical judgements when retrieving and pilfering cached Food. Different numbers of mealworms were presented sequentially to wild birds in a pair of artificial cache sites, which were then obscured from view. Robins frequently chose the site containing more prey, and the accuracy of their number discriminations declined linearly with the total number of prey concealed, rising above-chance expectations in trials containing up to 12 prey items. A series of complementary experiments showed that these results could not be explained by time, volume, orientation, order or sensory confounds. Lastly, a violation of expectancy experiment, in which birds were allowed to retrieve a fraction of the prey they were originally offered, showed that birds searched for longer when they expected to retrieve more prey. Overall results indicate that New Zealand robins use a sophisticated numerical sense to retrieve and pilfer stored Food, thus providing a critical link in understanding the evolution of numerical competency.
-
dominance rank influences Food Hoarding in new zealand robins petroica australis
Ibis, 2006Co-Authors: K. C. Burns, Jamie SteerAbstract:Social interactions are thought to be an important determinant of Food Hoarding behaviour in birds. Theoretical work predicts that subordinate birds should cache more to offset losses to dominant birds. However, empirical support for this prediction is mixed. We evaluated whether social dominance influences the Food Hoarding behaviour of New Zealand Robins Petroica australis. Robins provide a unique opportunity to test Food Hoarding theory because they are fearless of humans and will cache Food presented to them by hand. We offered mealworms to free-ranging male and female Robins to test whether (1) one sex was socially dominant, (2) the subordinate sex cached more frequently than the dominant sex and (3) birds cached more frequently when they were in the presence of a potential competitor. Our results indicate that males were dominant over females. Males acquired most of the prey offered to birds during trials and won all aggressive encounters observed between sexes. However, caching rates ran contrary to theoretical predictions. Males stored approximately twice as many mealworms as females. Both sexes also stored more Food when they were alone than when they were accompanied by conspecifics. We interpret the reluctance of females and paired birds to hoard Food as a strategy to avoid the loss of caches to competitors. Our overall results indicate that dominance rank strongly influences caching decisions, but that caching rates ran contrary to theoretical predictions.
-
an experimental evaluation of Food Hoarding by north island robins petroica australis longipes
2005Co-Authors: Laurel Alexander, Catherine Duthie, Joshua Fyfe, Zoe Haws, Simon Hunt, Carlos Ochoa, Arun Siva, Lloyd D Stringer, Jayden O Van Horik, K. C. BurnsAbstract:We experimentally evaluated the Food Hoarding behaviour of North Island robins (Petroica australis longipes) at Karori Wildlife Sanctuary, Wellington. Mealworms were offered to free-ranging pairs of male and female robins to evaluate whether their Food Hoarding behaviour was similar to previous observations of South Island robins. We also tested theoretical predictions derived in the Northern Hemisphere, which argue that competitively subordinate birds should hoard more Food than dominant birds. Results showed that the Food Hoarding behaviour of North Island robins was similar to South Island robins, except that North Island robins repeatedly used the same cache sites, which is rare in South Island robins. Data did not support the prediction that competitively subordinate birds hoard more Food than dominant birds. Males acquired most of the mealworms offered to birds during trials, and won nearly all aggressive interactions observed between sexes. Therefore, males appeared to be competitively dominant to females in winter. However, males stored over five times as many mealworms as females, which is opposite to theoretical predictions. We interpret the reluctance of females to cache Food as a strategy to avoid Food loss to competitively dominant males. Alexander, L.; Duthie, C.; Fyfe, J.; Haws, Z.; Hunt, S.; Montoya, I.; Ochoa, C.; Siva, A.; Stringer, L.; Van Horik, J.; Burns, K.C. 2005. An experimental evaluation of Food Hoarding by North Island robins (Petroica australis longipes). Notornis 52(3): 138-142.
Brett J W Teubner - One of the best experts on this subject based on the ideXlab platform.
-
pyy 3 36 into the arcuate nucleus inhibits Food deprivation induced increases in Food Hoarding and intake
Peptides, 2013Co-Authors: Brett J W Teubner, Timothy J. BartnessAbstract:Central administration of neuropeptide Y (NPY) increases Food intake in laboratory rats and mice, as well as Food foraging and Hoarding in Siberian hamsters. The NPY-Y1 and Y5 receptors (Rs) within the hypothalamus appear sufficient to account for these increases in ingestive behaviors. Stimulation of NPY-Y2Rs in the Arcuate nucleus (Arc) has an anorexigenic effect as shown by central or peripheral administration of its natural ligand peptide YY (3-36) and pharmacological NPY-Y2R antagonism by BIIE0246 increases Food intake. Both effects on Food intake by NPY-Y2R agonism and antagonism are relatively short-lived lasting ∼4h. The role of NPY-Y2Rs in appetitive ingestive behaviors (Food foraging/Hoarding) is untested, however. Therefore, Siberians hamsters, a natural Food hoarder, were housed in a semi-natural burrow/foraging system that had (a) foraging requirement (10 revolutions/pellet), no free Food (true foraging group), (b) no running wheel access, free Food (general malaise control) or (c) running wheel access, free Food (exercise control). We microinjected BIIE0246 (antagonist) and PYY(3-36) (agonist) into the Arc to test the role of NPY-Y2Rs there on ingestive behaviors. Food foraging, Hoarding, and intake were not affected by Arc BIIE0246 microinjection in fed hamsters 1, 2, 4, and 24h post injection. Stimulation of NPY-Y2Rs by PYY(3-36) inhibited Food intake at 0-1 and 1-2h and Food Hoarding at 1-2h without causing general malaise or affecting foraging. Collectively, these results implicate a sufficiency, but not necessity, of the Arc NPY-Y2R in the inhibition of Food intake and Food Hoarding by Siberian hamsters.
-
anti ghrelin spiegelmer inhibits exogenous ghrelin induced increases in Food intake Hoarding and neural activation but not Food deprivation induced increases
American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2013Co-Authors: Brett J W Teubner, Timothy J. BartnessAbstract:Circulating concentrations of the stomach-derived “hunger-peptide” ghrelin increase in direct proportion to the time since the last meal. Exogenous ghrelin also increases Food intake in rodents and humans, suggesting ghrelin may increase post-fast ingestive behaviors. Food intake after Food deprivation is increased by laboratory rats and mice, but not by humans (despite dogma to the contrary) or by Siberian hamsters; instead, humans and Siberian hamsters increase Food Hoarding, suggesting the latter as a model of fasting-induced changes in human ingestive behavior. Exogenous ghrelin markedly increases Food Hoarding by ad libitum-fed Siberian hamsters similarly to that after Food deprivation, indicating sufficiency. Here, we tested the necessity of ghrelin to increase Food foraging, Food Hoarding, and Food intake, and neural activation [c-Fos immunoreactivity (c-Fos-ir)] using anti-ghrelin Spiegelmer NOX-B11–2 (SPM), an l-oligonucleotide that specifically binds active ghrelin, inhibiting peptide-receptor interaction. SPM blocked exogenous ghrelin-induced increases in Food Hoarding the first 2 days after injection, and foraging and Food intake at 1–2 h and 2–4 h, respectively, and inhibited hypothalamic c-Fos-ir. SPM given every 24 h across 48-h Food deprivation inconsistently inhibited Food Hoarding after refeeding and c-Fos-ir, similarly to inabilities to do so in laboratory rats and mice. These results suggest that ghrelin may not be necessary for Food deprivation-induced foraging and Hoarding and neural activation. A possible compensatory response, however, may underlie these findings because SPM treatment led to marked increases in circulating ghrelin concentrations. Collectively, these results show that SPM can block exogenous ghrelin-induced ingestive behaviors, but the necessity of ghrelin for Food deprivation-induced ingestive behaviors remains unclear.
-
neural and hormonal control of Food Hoarding
American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2011Co-Authors: Timothy J. Bartness, Megan J Dailey, Erin Keenrhinehart, Brett J W TeubnerAbstract:Many animals hoard Food, including humans, but despite its pervasiveness, little is known about the physiological mechanisms underlying this appetitive behavior. We summarize studies of Food Hoarding in humans and rodents with an emphasis on mechanistic laboratory studies of species where this behavior importantly impacts their energy balance (hamsters), but include laboratory rat studies although their wild counterparts do not hoard Food. The photoperiod and cold can affect Food Hoarding, but Food availability is the most significant environmental factor affecting Food Hoarding. Food-deprived/restricted hamsters and humans exhibit large increases in Food Hoarding compared with their fed counterparts, both doing so without overeating. Some of the peripheral and central peptides involved in Food intake also affect Food Hoarding, although many have not been tested. Ad libitum-fed hamsters given systemic injections of ghrelin, the peripheral orexigenic hormone that increases with fasting, mimics Food deprivation-induced increases in Food Hoarding. Neuropeptide Y or agouti-related protein, brain peptides stimulated by ghrelin, given centrally to ad libitum-fed hamsters, duplicates the early and prolonged postFood deprivation increases in Food Hoarding, whereas central melanocortin receptor agonism tends to inhibit Food deprivation and ghrelin stimulation of Hoarding. Central or peripheral leptin injection or peripheral cholecystokinin-33, known satiety peptides, inhibit Food Hoarding. Food Hoarding markedly increases with pregnancy and lactation. Because fasted and/or obese humans hoard more Food in general, and more high-density/high-fat Foods specifically, than nonfasted and/or nonobese humans, understanding the mechanisms underlying Food Hoarding could provide another target for behavioral/pharmacological approaches to curb obesity.
-
body mass loss during adaptation to short winter like days increases Food foraging but not Food Hoarding
Physiology & Behavior, 2009Co-Authors: Brett J W Teubner, Timothy J. BartnessAbstract:Abstract Siberian hamsters markedly reduce their body/lipid mass (∼ 20–45%) in short ‘winter-like’ days (SD). Decreases in body/lipid mass associated with Food deprivation or lipectomy result in increases in foraging and Food Hoarding. When at their SD-induced body/lipid mass nadir, Food Hoarding is not increased despite their decreases in body/lipid mass, but Hoarding was not tested during the dynamic period of body/lipid mass loss (first 5–6 weeks of SDs). Therefore, we tested for changes in foraging/Hoarding during this initial period in Siberian hamsters housed in a simulated burrow with a wheel running-based foraging system and exposed to either long ‘summer-like’ days (LD) or SDs. Two foraging effort conditions were used: 10 Revolutions/Pellet (pellet delivered after running 10 revolutions) and a Free Wheel/Free Food condition (wheel available, Food pellets non-contingently available). Regardless of the foraging condition, body mass was significantly reduced across 8 weeks of SDs (∼ 15%). Foraging increased after 7 weeks in SDs, but Food Hoarding did not increase compared to LDs. Instead Food Hoarding significantly decreased in SDs at Weeks 2–5 compared with Week 0 values, with the 10 Revolutions/Pellet foraging group returning to LD levels thereafter and the Free Wheel/Free Food group remaining reduced from Weeks 2–7. Collectively, we found that SDs decreased body mass, increased foraging after 7 weeks, and increased Food Hoarding, but only after an initial decrease and not above that seen in LDs. These data suggest that SD-induced body/lipid mass losses do not engender similar behavioral responses as seen with Food deprivation or lipectomy.