Critical role of food amount for prefeeding corticosterone peak in rats

1983 ◽  
Vol 245 (3) ◽  
pp. R339-R344 ◽  
Author(s):  
K. I. Honma ◽  
S. Honma ◽  
T. Hiroshige

The effects of food on plasma corticosterone levels were examined in rats under restricted daily feeding or prolonged food deprivation. High hormone levels before feeding were observed when the daily meal was restricted to 2 h at a fixed time of day, but it was not detected when food availability was extended to 6 h. The amount of food intake under the latter condition was comparable to that in 24 h of ad libitum feeding. After the termination of restricted feeding, the prefeeding hormone peak was maintained in rats fasted subsequently but disappeared when rats were returned to ad libitum feeding. Food deprivation for 10 days increased plasma corticosterone levels in the light period, resulting in abolition of the circadian rhythm. A subsequent meal decreased the hormone level such that the 24-h mean hormone level after food ingestion was inversely related to the amount of food intake. When rats were allowed to feed for 6 h after prolonged food deprivation, the prefeeding hormone peak observed at the second meal disappeared at the fourth meal. The amount of food consumption in these rats increased and reached a level comparable to that with ad libitum feeding at the third meal. It is concluded that the amount of food intake is critical for the development and maintenance of the prefeeding hormone peak under restricted feeding; prolonged fasting.

1994 ◽  
Vol 266 (4) ◽  
pp. E606-E611
Author(s):  
M. Mitome ◽  
S. Honma ◽  
T. Yoshihara ◽  
K. Honma

Extracellular norepinephrine (NE) in the vicinity of the paraventricular nucleus was continuously measured over 24 h by means of in vivo microdialysis in rats under restricted daily feeding and ad libitum feeding. A 24-h rhythm in plasma corticosterone was monitored in separate rats under identical conditions. Under ad libitum feeding, the paraventricular NE showed a 24-h rhythm with lower levels in the light period and higher levels in the dark period. The temporal pattern was not affected by food deprivation for 3 days. The circadian peak of paraventricular NE lagged slightly behind that of plasma corticosterone under ad libitum feeding. On the other hand, when rats were fed for 2 h at a fixed time of day for 3 wk, the NE rhythm was changed and showed a major peak just before daily meals. To examine the nature of the prefeeding NE peak, a 24-hour variation of paraventricular NE was measured in rats under food deprivation that had been subjected to restricted daily feeding for 3 wk and subsequently to ad libitum feeding for 7 days. The paraventricular NE was high around the time when meal had been supplied under restricted daily feeding and low in the dark period. Similar changes were observed in plasma corticosterone. The findings indicate that the prefeeding increase in the paraventricular NE release is regulated by a feeding-associated circadian rhythm manifest in rats under restricted daily feeding.


1996 ◽  
Vol 271 (2) ◽  
pp. E239-E245 ◽  
Author(s):  
T. Yoshihara ◽  
S. Honma ◽  
Y. Katsuno ◽  
K. Honma

Extracellular neuropeptide Y (NPY) in the vicinity of the paraventricular nucleus (PVN) as well as NPY concentrations in the PVN were measured in rats under ad libitum feeding and 2-day and 10-day food deprivation. Plasma corticosterone levels were not changed by 2-day food deprivation but were increased by subsequent refeeding. In contrast, the extracellular NPY levels were increased by 2-day food deprivation and were decreased rapidly by refeeding. The NPY concentrations were also increased and increased further by refeeding. On the other hand, plasma corticosterone levels were elevated by 10-day food deprivation and were decreased by subsequent refeeding. The extracellular NPY levels were also increased by food deprivation and decreased gradually after refeeding. However, the postprandial levels were still elevated when plasma corticosterone levels were returned to the basal levels. The NPY concentrations were also increased and increased further by refeeding. The amount of food intake after refeeding was positively correlated with the extracellular NPY levels. It is concluded that extracellular NPY levels in the PVN do not necessarily covariate with plasma corticosterone levels in rats under food deprivation.


2001 ◽  
Vol 280 (3) ◽  
pp. R669-R677 ◽  
Author(s):  
Elizabeth M. Starbuck ◽  
Douglas A. Fitts

A lesion of the subfornical organ (SFO) may disrupt drinking after a meal of dry chow as it does drinking after intragastric administration of hypertonic saline. Food and water intakes of SFO-lesioned (SFOX) and sham-lesioned rats were measured during 90-min tests following various lengths of food deprivation. During the tests, all rats began eating before they began drinking. After 20–24 h of food deprivation, latency to begin drinking after eating had started was longer for SFOX than for sham-lesioned rats. Plasma osmolality was elevated by 2–3% in both lesion groups at 12 min, the latency for sham-lesioned rats to drink, but SFOX rats nevertheless continued eating and delayed drinking. Eating after shorter 4-h food deprivations and ad libitum feeding produced more variable drinking latencies and less consistent effects of SFO lesion. During 24 h of water deprivation, SFO lesion had no effect on the suppression of food intake and did not affect food or water intakes during the first 2 h of subsequent rehydration. These findings indicate that the SFO is involved in initiating water intake during eating and in determining drinking patterns and the amount of water ingested during a meal.


1996 ◽  
Vol 62 (3) ◽  
pp. 531-540 ◽  
Author(s):  
J. C. Kerr ◽  
N. D. Cameron

AbstractGenetic and phenotypic relationships between performance test and reproduction traits were estimated, after five generations of divergent selection for components of efficient lean growth, in a population of Large Wltite pigs. On ad-libitum feeding, a total of 4334 pigs were performance tested, of which 884 selected gilts had measurements of reproduction traits. On a restricted feeding regime, 1558 pigs were tested, which included 336 selected gilts with reproduction records. For pigs given food ad libitum, genetic correlations between litter weights at birth and weaning with daily food intake (0·48 and 0·42, s.e. 0·16) and with growth rate on test (0·65 and 0·52) were positive, but correlations with backfat depths were not significantly different from zero. For pigs given food at a restricted level, litter birth weight was positively genetically correlated with growth rate (0·50, s.e. 0·18) and negatively correlated with backfat depths (-0·48, s.e. 0·16). Phenotypic and environmental correlations between performance test and reproduction traits were all less than 0·10 in magnitude, for pigs tested on either feeding regime. The variation in backfat depth enabled detection of a non-linear relationship between predicted breeding values for litter weight at birth with predicted breeding values for average backfat depth of farrowing gilts performance tested on ad-libitum feeding, but not for gilts tested on restricted feeding. The positive genetic correlations between growth rate and daily food intake with litter traits suggested that selection strategies which change growth and daily food intake may result in relatively greater genetic changes in piglet growth rate than in litter size.


1978 ◽  
Vol 18 (94) ◽  
pp. 658 ◽  
Author(s):  
D Robinson ◽  
G Horsnell ◽  
PJ McMahon

White Leghorn x Australorp crossbred pullets were either fed ad libitum or given restricted access to food from 8 to 20 weeks of age. Birds from each of these rearing treatments were thereafter distributed among five feeding regimes: ad libitum and four allowances representing reductions of 3, 6, 12 and 24 per cent of the food intake of the birds fed ad libitum throughout life. Biological and economic performance data were examined for the rearing period and for three periods of lay terminating at 66, 78 and 90 weeks of age. From 8 to 20 weeks of age the restrictively reared pullets ate 30.5 per cent less food, suffered 1.7 per cent higher mortality, cost 19 cents per bird less to rear and were 20.5 per cent lighter in weight at 20 weeks than the pullets fed ad libitum. Compared with ad libitum feeding, restricted feeding in the rearing period gave higher values for hen-housed egg production and hen-housed gross margin when food intake in lay was restricted by 0, 3 and 6 per cent, and lower values for these criteria when food intake in lay was restricted by 12 and 24 per cent. Birds whose food intake was restricted by 6 per cent in the laying period laid about 25 more eggs to 90 weeks of age than birds fed ad libitum in lay. Optimum slaughter time (age at which average gross margin per week was maximized) was at about week 90 for the ad libitum/12 per cent restriction and ad libitum/24 per cent restriction treatments, and between weeks 66 and 78 for all other treatments. The highest weekly average gross margin was achieved with the birds that were restrictively reared and restricted by 6 per cent throughout a laying period terminating at 78 weeks of age; at this stage their gross margin was $2.30 per bird higher than that of the birds fed ad libitum throughout life


1996 ◽  
Vol 270 (4) ◽  
pp. E589-E595 ◽  
Author(s):  
T. Yoshihara ◽  
S. Honma ◽  
K. Honma

Extracellular neuropeptide Y (NPY) in the vicinity of the paraventricular nucleus (PVN) and the NPY concentrations in the PVN, arcuate nucleus of the hypothalamus (ARC), and the nucleus tractus solitarius (NTS) were measured in rats under ad libitum and restricted daily feeding (RF) where meal was supplied at a fixed time of day. The extracellular NPY levels did not vary significantly between 0600 and 2200 in rats under ad libitum feeding but were increased before meal and decreased immediately after mean supply under the RF regimen. Similarly, the NPY concentrations in the PVN, ARC, and NTS were increased immediately before meal. When meal was omitted at the regular mealtime, the extracellular NPY levels were not decreased rapidly, and the NPY concentration in the PVN remained at a low level. Rats were subjected to the feeding-fasting paradigm after the termination of RF. The extracellular NPY levels were returned to basal levels during the feeding period but were elevated during the fasting period at almost the same time as that for meal supply under the RF regimen. It is concluded that the prefeeding enhancement of the NPY release in the PVN under the RF regimen is regulated by the feeding-associated circadian rhythm.


1999 ◽  
Vol 277 (6) ◽  
pp. R1749-R1759 ◽  
Author(s):  
Elena Timofeeva ◽  
Yves Deshaies ◽  
Frédéric Picard ◽  
Denis Richard

The present study was conducted to verify whether experimental conditions such as obesity and food deprivation, which promote food intake and reduce thermogenesis, could modify the expression of the corticotropin-releasing hormone (CRH)-binding protein (BP) in the rat brain. In situ hybridization, histochemistry, and immunohistochemistry were used to assess the expression of CRH-BP in lean ( Fa/?) and obese ( fa/fa) Zucker rats that were fed ad libitum, food deprived for 24 h, or food deprived for 24 h and refed for 6 h. In both lean and obese rats, food deprivation led to a reduction in body weight that was accompanied by a reversible increase in plasma corticosterone levels. Food deprivation and, to a lesser degree, obesity induced the expression of CRH-BP mRNA in the dorsal part of the medial preoptic area (MPOA). This induction of the CRH-BP gene led to by food deprivation was confirmed by the appearance in the dorsal part of the MPOA of neurons immunoreactive to CRH-BP. Food deprivation (in particular) and obesity also increased the levels of CRH-BP mRNA in the basolateral amygdala (BLA). The enhanced CRH-BP expression in the MPOA and BLA in response to food deprivation was reversed by refeeding. In lean Fa/? rats, the CRH-BP mRNA level in the pituitary cells was significantly decreased after food deprivation and restored after refeeding. When food was provided ad libitum, the number of cells expressing CRH-BP in the anterior pituitary was significantly higher in lean rats than in obese animals. Food deprivation for 24 h decreased dramatically the number of pituitary cells expressing CRH-BP in lean rats. Altogether, the present results demonstrate that food deprivation and, to a lesser extent, obesity can selectively affect the expression of CRH-BP. Given both the inactivating effect of CRH-BP on the CRH system and the potential roles played by the MPOA and BLA in the thermogenic and anorectic effects of CRH, it can be argued that the induction of the CRH-BP gene in obesity and after food deprivation occurs as a mechanism to reduce energy expenditure and to stimulate food intake.


2014 ◽  
Vol 14 (1) ◽  
pp. 89-100
Author(s):  
Włodzimierz Nowak ◽  
Robert Mikuła ◽  
Ewa Pruszyńska-Oszmałek ◽  
Barbara Stefańska ◽  
Paweł Maćkowiak ◽  
...  

AbstractThe aim of the study was to investigate experimentally the effects of restricted or ad libitum feeding in the far-off period on performance of dairy cows. Two groups of Polish Holstein-Friesian cows having 19 animals in each group were allotted to two planes of nutrition in the far-off period from -56 to -22 days. The ADLIB group was fed ad libitum (DMI 12.9 kg) while in the RES group the dry matter intake was restricted by 3 kg DM compared to the average dry matter during the last 7 days in the ADLIB group. Average daily energy intake decreased from 8.90 UFL in the ADLIB to 6.83 UFL in the RES group. In the close-up period and after parturition, the cows of both groups were given the same diet. In restrictively fed cows, there was a tendency to a greater decrease in BCS during both the dry period (P=0.09) and lactation (P=0.07). After parturition milk production, fertility indices and blood concentration of IGF-1, insulin and glucose were not significantly affected by the far-off treatment. In the RES group, lower BHBA 3 days before calving and on day 5 of lactation and lower NEFA on day 28 of lactation were recorded. Also in this group higher levels of glucose 3 days before calving, triiodothyronine (T3) on days -30 and 5, and thyroxine (T4) on days -3 and 28 were observed. It is concluded that restricted feeding in the far-off period positively affected blood indicators of lipomobilization during the transition period, but had little effect on performance of lactating cows. In spite of low energy, high-fibre diet offered ad libitum in the faroff period resulted in the energy overfeeding compared to the INRA system recommendation.


1996 ◽  
Vol 1996 ◽  
pp. 17-17
Author(s):  
J. C. Kerr ◽  
N. D. Cameron

Responses in sow traits at farrowing and during lactation and in pre-weaning piglet growth rate were determined in a population of Large White pigs, after seven generations of divergent selection for components of efficient lean growth rate. Information on the factors influencing preweaning piglet growth rate is required for a comprehensive evaluation of alternative selection strategies.There were four selection groups: daily food intake (DFI), lean food conversion (LFC), lean growth rate (LGA) on ad-libitum feeding and lean growth rate on scale feeding (LGS). There were 242 gilts in the study, with 20 gilts in the high, low and control lines of each selection group. Pigs in the ad-libitum selection groups were performance tested over a fixed weight range of 30 to 85 kg. Pigs fed on scale feeding were performance tested for a fixed time period of 84 days from 30 kg with food intake equal to 0.75 g/g of daily ad-libitum food intake. Matings were unsupervised and took place in outside paddocks.


1984 ◽  
Vol 24 (124) ◽  
pp. 77 ◽  
Author(s):  
BA McGregor

Kids six months old and of mean liveweight 22 kg were offered a basal ration of barley and lupins (crude protein 15 .4%) supplemented with three levels of chopped hay (0, 13% of total intake and ad libitum). Supplementation of the basal ration with 13% hay increased total dry matter intake from 479 to 753 g/d (P< 0.001) and liveweight gain from 10 to 54 g/d (P<0 .01). Non-significant increases in total food intake and liveweight gains were achieved by supplementing with ad libitum hay; kids fed ad libitum hay actually consumed 26.9% of their diet as hay. They were then offered various mixtures of barley, oats and lupins with 13% chopped hay at near ad libitum feeding. Differences in intake or growth were not significant at P= 0.05 with kids growing at 74, 65 and 101 g/d for those fed barley, oats and lupins respectively. Results indicate that highest food intake was obtained when 13% chopped hay was added to whole barley grain rations.


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