Meal-related and rhythmic drinking: effects of abolition of rat's eating rhythm

1991 ◽  
Vol 261 (1) ◽  
pp. R14-R19 ◽  
Author(s):  
R. F. Johnson ◽  
A. K. Johnson

Eating and drinking in the rat, which are both highly rhythmic and nocturnal activities, are temporally and quantitatively associated. The present study abolished the rhythmicity of eating by temporally and quantitatively restricting food access to 12 equally sized bihourly meals daily (total food available was equal to 80% of daily ad libitum intake). Water access remained ad libitum and was monitored and quantified in terms of 1) nocturnality, 2) association with meals, and 3) changes in the association of food and water intake across the phases of the light-dark cycle. Similar parameters were obtained from the same rats with ad libitum access to both food and water. The results indicate that both rhythmic and meal-induced effects are detectable in the drinking of rats with restricted food access, although both the rhythmic and meal-associated factors are reduced compared with drinking under ad libitum food access. Most important, the data clearly demonstrate large changes in the association of food and water intake across the phases of the light-dark cycle. These findings indicate a complex interaction of meal-associated and rhythmic factors in the control of drinking.

2005 ◽  
Vol 81 (1) ◽  
pp. 99-105 ◽  
Author(s):  
W. Yape Kii ◽  
G. McL. Dryden

AbstractThe salinity tolerance of Javan rusa deer (Cervus timorensis russa) was investigated with seven stags, aged 4·5 years. Animals were offered a medium-quality chaffed lucerne hay and given five different levels of water salinity: (a) control (570 mg/kg of total dissolved salts (TDS)) and (b) ‘saline’ water with TDS contents of 1000, 3500, 6000 and 8500 mg/kg. Food intake, food digestibility and nitrogen balance were not affected by increasing salt concentration in drinking water, however the drinking water (DW) intake, the total (food plus drinking) water intake and the DW:dry-matter ratio increased with increasing salt concentration. Some deer given water containing 8500 mg TDS per kg showed signs of stress which included large between-day fluctuations in water intake, opening of the orbital gland, head shaking, and rapid breathing. Rusa deer can tolerate drinking water containing 6000 mg TDS per kg for at least 9 days without harmful effect but may be unable to tolerate water with 8500 mg TDS per kg.


1994 ◽  
Vol 72 (8) ◽  
pp. 841-848 ◽  
Author(s):  
G. Harvey Anderson ◽  
Shuqin Luo ◽  
Leonidas Trigazis ◽  
Greta Kubis ◽  
Edmund T. S. Li

This study examined the effects of selected groups of essential amino acids (EAAs), given by gavage, on short-term food and water intake. Amino acid groups were selected on the basis of their common physiologic functions in relation to current hypotheses on the role of amino acids in food intake control, and the quantities given were based on the proportions in 1.5 g of the EAA content of albumin. The complete EAA mixture (1.5 g) suppressed food intake by an average of 60 and 37% during the 1st and 2nd h of feeding, respectively, but had no influence on feeding in the subsequent 12 h. Total daily (14 h) intake was decreased by 9%. With the exception of the aromatic amino acid (Phe + Tyr + Trp, 0.34 g) group, all groups significantly decreased food intake by a comparable magnitude (32%) during the 1st h. In this time period, rats given the EAAs, Arg + Met + Val (0.38 g), and Arg + His + Lys (0.44 g) mixtures increased their water intake, whereas intake by rats given the Phe + Tyr + Trp + Thr (0.46 g) and Ile + Leu + Val (0.45 g) mixtures was unchanged. Thus, the food intake suppression caused by EAAs was not accounted for by an equal effect of its component amino acid groups. As well, food intake suppression by amino acid groups was not explained by increased water consumption, nor was it simply related to the quantity of nitrogen provided by the treatment.Key words: food intake, water intake, essential amino acids.


2021 ◽  
Vol 10 (36) ◽  
pp. 125-127
Author(s):  
Fabiana Nabarro Ferraz ◽  
Valdir Antônio Gonçalves ◽  
Denise Lessa Aleixo ◽  
Angélica Sayuri Mizutani ◽  
Silvana Marques de Araújo

Background: Biotherapy is used against infectious diseases treatment and prophylaxis and has been investigated by many researchers [1,2]. Aim: Assess the effect of biotherapy 7x T. cruzi on several treatment schemes, upon experimental infection by T. cruzi. Methodology: A blind, controlled and randomized by drawing experiment was performed. Male Swiss mice, four weeks old were utilized. Groups evaluated: IC – Infection Control (treated with water – 9 animals); TBBA7x3days – Treated with biotherapy 7x 3 days before and 3 days after infection (5 animals); TBB7x3days – Treated with 7x biotherapy 3 days before infection (5 animals); TBBAI7x3days – Treated with 7x biotherapy 3 days before infection and after infection indefinitely (6 animals). Animals were inoculated intraperitoneally with 1400 blood trypomastigotes Y strain. Biotherapy: prepared according to Farmacopéia Homeopática Brasileira [3]. Treatment plan: offered ad libitum, in the water (10µL/mL). Parasitological parameters: parasitemia was assessed according Brener’s technique. [4]. Clinical parameters: body hair aspect, edema, movement, diarrhea, body weight, temperature, food and water intake. Ethics: Registration 030/2008 UEM Ethics Committee for Experiments in Animals. Statistical analysis: was performed using the tests Kruskal Wallis and Mann-Whitney testes, significance 5%. Results: The best effect obtained was with the TBBA7x3days, both for clinical and parasitological parameters. It was expressed by lower parasitemia curve (p=0.04) and decrease of patent period tendency, of total parasitemia, of mortality and survival of the animals increase (Table 1). Evolution of parasitemia was distinct for the several treatment schemes. Survival of at least one mouse by treated groups is an extremely important data, since Y strain causes 100% mortality in Swiss mice. TBBAI7x3days group showed begger tendency in raising total parasitemia compared with IC. Although it might have occurred, this group presented 80% mortality rate compared with other groups. Animals from TBBA7x3days also showed better evolution of weight body, temperature, food (p=0.078-10%) and water intake, body hair aspect and edema development. Diarrhea and paralysis were only observed in IC group mice, highlighting the biotherapy use benefits. Conclusions: Best effect was obtained TBBA7x3days, both for clinical and parasitological parameters. It’s possible to speculate that in this regimen, biotherapy was able to modulate, more effectively, the host’s immune system, decreasing the number of parasites.


1983 ◽  
Vol 245 (1) ◽  
pp. F48-F57
Author(s):  
H. T. Campbell ◽  
P. A. Craven ◽  
F. R. DeRubertis

The effects of fluid intake on basal and vasopressin-responsive urinary PGE excretion (UPGEV) were examined in conscious rats under conditions of 1) ad libitum water intake, 2) water deprivation, and 3) water diuresis induced by ad libitum intake of 5% dextrose in water. UPGEV fell progressively during 40 h of water deprivation. Water diuresis after water deprivation increased UPGEV transiently (8 h). Vasopressin (Pitressin tannate in oil, 5 U/kg subcutaneously) increased UPGEV and decreased urine volume (V) in rats on ad libitum water intake but did not alter UPGEV during water deprivation. Indomethacin suppressed UPGEV (70-90%), increased basal urine osmolality (Uosmol), and potentiated the antidiuretic response to Pitressin in rats on ad libitum water intake. Indomethacin accelerated by 8 h the onset of maximal antidiuresis in water-deprived rats but did not significantly alter water balance. During water diuresis, UPGEV declined in the first 8 h after Pitressin. Thereafter, UPGEV increased markedly, concurrent with early vasopressin escape. Indomethacin or meclofenamate inhibited the rise in UPGEV, the decline in Uosmol, and the increase in V of the escape phase. Indomethacin or meclofenamate also impaired the excretion of an acute water load (5% body wt) given during escape. The spontaneous decline in UPGEV during hydropenia may serve to maximize physiologic antidiuresis. Conversely, the marked increase in UPGEV induced by administration of vasopressin during water diuresis may serve to suppress the antidiuretic response and thus play a role in the mediation of escape from physiologically inappropriate antidiuresis.


1979 ◽  
Vol 42 (2) ◽  
pp. 253-266 ◽  
Author(s):  
N. Jackson ◽  
Mary H. Stevenson ◽  
G. McC. Kirkpatrick

1. Two experiments are reported. In both experiments a cereal-based diet containing 5 mg copper/kg was fed to two breeds of laying hens for 336 d. In Expt I four other groups were given this diet with the addition of CuSO4.5H2O to give added levels of 200, 400, 600 and 800 mg Cu/kg diet. In Expt 2 the levels of added dietary Cu used were 100, 200, 300 and 400 mg/kg.2. In Expt I records were kept of food intake, water intake, body-weight and egg production for eight 28 d periods and body-weight and egg number only were recorded for the full twelve periods. In Expt 2 full records, excluding water intake, were taken for all twelve periods.3. Food and water intake showed a quadratic response to level of added dietary Cu, being enhanced at lower levels and depressed at higher levels of addition.4. There was a quadratic response of total egg weight, mean egg weight and egg number to added dietary Cu. In Expt I egg number was maximum at 235 mg added Cu/kg diet for Warren Studler SSL (breed I) and at 170 mg added Cu/kg diet for Shaver 288 (breed 2). In Expt 2 no breed effect occurred, the maximum egg number being calculated to occur at 176 mg added Cu/kg diet.5. Depression of body-weight gain occurred at high lelvels of Cu addition. The depression of liver and oviduct weight found at high levels of addition appeared to be directly related to body-weight. A marked amount of feather loss also occurred at a high inclusion of CuSO4 in the diet.6. The reproductive systems of the hens did not appear to be adversely affected at the levels of additive used. Gross and microscopic examination of specific tissues revealed no pathological effects although gizzard and intestinal weights were increased and caecal weight decreased by high levels of added Cu. Those aspects of the blood chemistry examined did not reveal any consistent effect between the two experiments.7. The liver Cu analyses indicate that between 600 and 800 mg added Cu/kg diet liver Cu concentration rises sharply. Both liver Fe and Zn concentrations showed a positive linear response to added dietary Cu. In the kidney Cu and Zn concentrations were increased but only to a limited extent, while the concentration of Fe was unaffected.


2002 ◽  
Vol 80 (3) ◽  
pp. 812-817 ◽  
Author(s):  
G. N. Hermesmeyer ◽  
L. L. Berger ◽  
N. R. Merchen ◽  
T. G. Nash

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