Seasonal changes in growth rate, feed intake, growth hormone, and thyroid hormones in young male reindeer (Rangifer tarandus tarandus)

1982 ◽  
Vol 60 (1) ◽  
pp. 15-23 ◽  
Author(s):  
Morten Ryg ◽  
Endre Jacobsen
Keyword(s):  
Growth Hormone ◽  
Feed Intake ◽  
Seasonal Changes ◽  
Rangifer Tarandus ◽  
Young Male ◽  
Early Spring ◽  
Late Winter ◽  
Seasonal Patterns ◽  
Restricted Feeding ◽  
Ad Libitum

The levels of thyroxine (T4), triiodothyronine (T3), and growth hormone (GH) in blood serum from young male reindeer have been measured and compared with changes in body weight and feed intake during ad libitum and restricted feeding. All three hormones fluctuated during the year. T3 changed in response to changes in feed intake. T4 and GH seemed to have basic seasonal patterns, which were modified by differences in feed intake. GH rose to high levels in late winter – early spring. T4 levels were higher in summer than in winter, corresponding roughly to changes in weight gain and feed intake.

The effect of restricted feeding on growth hormone (GH) secretory patterns in genetically lean and fat wether lambs

2000 ◽  
Vol 70 (3) ◽  
pp. 425-433 ◽  
Author(s):  
S. M. Francis ◽  
R. P. Littlejohn ◽  
S. K. Stuart ◽  
B. A. Veenvliet ◽  
J. M. Suttie
Keyword(s):  
Growth Hormone ◽  
Treatment Group ◽  
Developmental Change ◽  
Plasma Concentrations ◽  
Live Weight ◽  
Carcass Composition ◽  
Restricted Feeding ◽  
Ad Libitum ◽  
Plasma Gh ◽  
And Control

AbstractThe aim of this work was to determine whether developmental changes in growth hormone (GH) secretory patterns and carcass composition were influenced by nutrition and genotype in sheep. Four-month-old wether lambs from lean (low backfat), fat (high backfat) and control selection lines were nutritionally restricted to maintain a 28 kg live weight or given food ad libitum for 24 weeks. Plasma concentrations of GH and insulin-like growth factor 1 (IGF-1) were measured at predetermined times and carcass composition of the animals determined at the end of the trial.From week 3 on, restrictions in dry matter (DM) intake were observed as the ad libitum treatment group had a significantly greater intake than the restricted treatment group (7·70 v. 5·80 kg DM per week, s.e.d. = 0·81). Differences in live weight between the feeding treatments were significant (P < 0·05) at week 9. The restricted feeding regime was associated with significant reductions in plasma levels of IGF-1 but had no effect (P > 0·05) on carcass weight-adjusted carcass fat proportion at the close of the trial. The effect of food restriction on GH secretory patterns was variable. Although there was initially a suppression in mean plasma GH, there was subsequently significantly higher mean plasma GH in the restricted feeding treatment. Periodogram analysis indicated that both the absolute levels of GH and the GH secretory pattern were altered by restricted feeding. In all animals, mean and basal GH concentrations, as well as the frequency and amplitude of pulses, declined from February to March and then increased from May to July (P < 0·001).DM intake and live weight did not differ (P > 0·05) between genotypes, however the fat genotype had greater carcass fatness than lean or control genotypes (P < 0·01). There were no consistent differences between genotypes in plasma IGF-1 concentrations. In the ad libitum treatment, the lean and control genotypes had higher plasma GH levels than the f at genotype but the pattern of GH release did not vary. Under restricted feeding, both the pattern and the level of plasma GH varied between genotypes.It is concluded that the developmental change in GH secretory patterns is affected by nutrition but not in a consistent manner. Although restricted feeding resulted in higher mean plasma GH concentrations later in the trial, this did not result in a change in carcass composition. The biological cues which lead to increased fat deposition in older lambs need further study but plasma GH levels may not he an important mechanism in this process.

Effect of residual feed intake phenotype–nutritional treatment interaction on the growth performance, plasma metabolic variables and somatotropic axis gene expression of growing ewes

2016 ◽  
Vol 56 (10) ◽  
pp. 1593 ◽  
Author(s):  
H. T. Nie ◽  
Z. Y. Wang ◽  
S. Lan ◽  
H. Zhang ◽  
Y. J. Wan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Growth Hormone ◽  
Growth Performance ◽  
Feed Intake ◽  
Mrna Abundance ◽  
Feed Restriction ◽  
Somatotropic Axis ◽  
Nutritional Treatment ◽  
Treatment Interaction ◽  
Ad Libitum

This study aimed to evaluate the effect of residual feed intake (RFI) phenotype and nutritional treatment interaction on the growth performance, plasma variables and gene expression levels within the somatotropic axis. Growing ewes [n = 52, initial bodyweight (BW) = 17.5 ± 0.5 kg, 2 months of age] were offered ad libitum access to diets for 63 days and ranked based on RFI phenotype. Thirty ewes with the highest and lowest RFI values were selected and randomly assigned to three nutritional treatments based on dry matter intake (DMI), which are ad libitum (AL), low restriction (LR) and high restriction (HR) groups, respectively. Each nutritional treatment group included ewes with high (n = 5) and low RFI (n = 5) values. During nutritional treatment (from Day 64 to Day 138), plasma samples were obtained to measure metabolite and hormone concentrations. Tissues of the hypothalamus, pituitary, liver, and Longissimus dorsi muscle (LM) were harvested at the end of the experiment (Day 138) to measure the gene expression level within the somatotropic axis. Muscle growth hormone receptor mRNA abundance of low RFI ewes tended to be greater (P = 0.09) under AL feeding, but this difference was abolished by underfeeding (P > 0.10). Low RFI ewes under HR treatment showed slightly greater growth performance, which was accompanied with lower pituitary somatostain receptor 2 mRNA abundance (P < 0.05), plasma non-esterified fatty acid concentration (P < 0.05), and greater concentration of triglyceride (P < 0.05), compared with ewes classified as high RFI group. Our results suggested that ewes categorised as low RFI showed higher resistance to the condition of high feed restriction, which might be attributed to less intensity of fat mobilisation under negative energy balance. The mechanism underlying resistance to such feed restriction was presumably through action of somatostain receptor 2 and was potentially mediated by inhibitory effects of somatostatin on growth hormone release but not basal growth hormone secretion.

scholarly journals Effect of the GH secretagogue L-163,255 and restricted feeding time on GH pulsatility in the rat

2002 ◽  
pp. 143-148 ◽  
Author(s):  
AN Moulas ◽  
JD Veldhuis ◽  
JC Chan ◽  
Keyword(s):  
Growth Hormone ◽  
Oral Administration ◽  
Feeding Time ◽  
Restricted Feeding ◽  
Growth Hormone Secretagogue ◽  
Deconvolution Analysis ◽  
Blood Samples ◽  
Pulsatile Release ◽  
Before And After ◽  
Ad Libitum

OBJECTIVE: To determine the effect of repeated treatments with the growth hormone secretagogue (GHS) L-163,255 on the pulsatile release of GH when administered in meal-fed rats before and after feeding. DESIGN: The first group of rats (AL, n=6) had food available ad libitum. The second (restricted, R, n=6), third (GHSB, n=6), and fourth (GHSA, n=6) groups were fed from 1100 to 1400 h. Groups GHSB and GHSA were given GHS by gavage, 3.0 mg/kg L-163,255, at 1000 h (before feeding, B) and at 1500 h (after feeding, A) respectively. Three weeks after the initiation of the treatment, blood samples were collected at 10-min intervals over 6 h, and GH levels were determined. RESULTS: In group R, the concentrations of GH were higher before feeding (17.6+/-2.4 ng/ml) than during feeding (11.2+/-1.2 ng/ml), P<0.05. The average concentrations of the peak in response to GHS were higher when GHS was administered before (121.70+/-33.68 ng/ml) than after (49.67+/-17.87 ng/ml) feeding. The mass of GH, as calculated by deconvolution analysis was also higher in the GHSB group than in the GHSA group (251.6+/-64.1 ng/ml per min vs 85.3+/-22.9 ng/ml per min respectively, P<0.05). CONCLUSION: L-163,255 is effective in inducing GH release after repeated oral administration in rats. The effectiveness is greater when GHS is administered before rather than after feeding in meal-fed animals.

Pre-pubertal mammogenesis in the sheep 3. The effects of restricted feeding or daily administration of bovine growth hormone and bromocriptine on mammary growth and morphology

1986 ◽  
Vol 42 (1) ◽  
pp. 53-63 ◽  
Author(s):  
I. D. Johnsson ◽  
I. C. Hart ◽  
A. Turvey
Keyword(s):  
Growth Hormone ◽  
Weight Gain ◽  
Live Weight ◽  
Restricted Feeding ◽  
Fat Pad ◽  
Live Weight Gain ◽  
Parenchymal Tissue ◽  
Mammary Fat Pad ◽  
Ad Libitum ◽  
Plasma Gh

ABSTRACTIn crossbred female lambs reared on a concentrate diet between 8 and 20 weeks of age, a restriction in food intake to 40 g/kg body weight per day decreased live-weight gain (155 g/day) compared with that in control lambs fed ad libitum (284 g/day) and significantly reduced final live weight and the size of the mammary fat pad (P < 0·001). However, restricted lambs at 20 weeks had more total parenchymal deoxyribonucleic acid (DNA; 54·7 v. 47·5 mg) occupying a greater mass of mammary fat pad (17·0 v. 13·2 g) than control lambs (P > 0·10). Restricted feeding had little effect on mean plasma growth hormone (GH) concentrations at 12 and 18 weeks of age, but decreased plasma insulin and prolactin concentrations.In lambs fed ad libitum, daily subcutaneous (s.c.) injections of 0·1 mg bovine pituitary GH per kg live weight between 8 and 20 weeks of age significantly increased daily live-weight gain (347 g/day; P < 0·001) and also increased total mammary parenchymal DNA (71·2 mg; P < 0·10) and the mass of fat pad occupied by parenchymal tissue (20·6 g; P < 0·05), compared with the control treatment. Daily s.c. injection of bromocriptine (1 mg/day) had no effect on either body or mammary growth, but tended to reduce the effects of bovine GH when given in combination. Secretory activity was observed in the parenchymal tissue of the eight lambs receiving bovine GH alone, and also in five control lambs and three lambs receiving bromocriptine alone. Three lambs that had attained puberty by 20 weeks of age had the poorest mammary development of their respective treatment groups.Mammary gland development at 20 weeks of age was significantly correlated across treatment means with plasma GH concentrations estimated at 18 weeks of age (r = 0·95; P < 0·05), but no correlations of similar magnitude were found between individuals within treatments at 20 weeks. Strongest correlations were found among 8-week-old lambs, where mammary parenchymal DNA was positively correlated with mean plasma GH (r = 0·62) and the GH:insulin ratio (r = 0·79) and negatively correlated with the prolactin:GH ratio (r = -0·65).

scholarly journals Time-Restricted Feeding in Commercial Layer Chickens Improves Egg Quality in Old Age and Points to Lack of Adipostat Activity in Chickens

2021 ◽  
Vol 12 ◽  
Author(s):  
Ganesan Saibaba ◽  
Mark Ruzal ◽  
Dima Shinder ◽  
Sara Yosefi ◽  
Shelly Druyan ◽  
...  
Keyword(s):  
Feed Intake ◽  
Visceral Fat ◽  
Egg Production ◽  
Egg Quality ◽  
Feed Consumption ◽  
Control Group ◽  
Restricted Feeding ◽  
Fat Accumulation ◽  
Visceral Fat Accumulation ◽  
Ad Libitum

In mammals, time-restricted feeding (TRF) with no caloric restriction provides health benefits and extends longevity, usually with a minor (∼3%) or no reduction in total food consumption. In the current study, a TRF regimen of 6 h free access to food (08:00–14:00 h) was applied to Leghorn chickens from 25 to 86 weeks of age; control birds ate freely during the light hours (06:00–20:00 h). Unexpectedly, the TRF-treated birds consumed, on average, 11.7% less food than the controls. This was manifested by an average reduction of 9.6% in body weight, 2.6-fold in visceral fat accumulation, and 6.5% in egg weight. Hen-housed egg production was reduced by 3.6% in the TRF group compared with the control, along the first 40 weeks of the follow-up (P &lt; 0.05), and changed into a tendency of 0.7% higher egg production thereafter. Several parameters of egg quality showed significant improvement (P &lt; 0.05) in the TRF group compared with the controls. A comparison of diurnal patterns of feed consumption revealed a higher rate of hourly consumption in the TRF group and increased consumption before dark in the control group. In conclusion, the reduced feed intake in response to the TRF treatment and loss in visceral fat accumulation supports the lack of a strong adipostat activity in chickens and different appetite regulation mechanisms compared with mammals. Therefore, future TRF studies in chickens should be adjusted by extending the ad libitum time window. The lower feed intake by the TRF-treated chickens compared with the ad libitum-fed controls seems to reduce the efficiency of egg production. Nevertheless, the improved egg quality and persistence of egg lay at the older age suggest that similarly to mammals, the TRF treatment delayed at least some of the negative impacts associated with advanced age.

The effect of plane of nutrition and shearing on the pattern of the moult in Scottish Cashmere goats

2002 ◽  
Vol 74 (1) ◽  
pp. 177-188 ◽  
Author(s):  
M. Merchant ◽  
D.J. Riach
Keyword(s):  
Seasonal Changes ◽  
Early Spring ◽  
Energy Requirements ◽  
Plasma Prolactin ◽  
Length Data ◽  
Cashmere Goats ◽  
Ad Libitum ◽  
Maintenance Requirements ◽  
Circulating Levels ◽  
Staple Length

AbstractThe effect of plane of nutrition on the timing of the moult in cashmere goats was investigated. Three groups of mature does were individually offered food to supply 0·8 (L, no. = 14), 1·2 (M, no. = 14) or 20 (H, no. = 13) times their estimated maintenance energy requirements from mid December until mid May. Two other groups of goats which were shorn in mid January, were offered 1·2 times maintenance requirements from mid December until mid March when food levels were increased to either 1·6 M (SL, no. = 6) or ad libitum (SAL, no. = 6). In mid May mean live weights for treatments L, M, H, SL and SAL were 36·0, 41·5, 46·9, 33·0 and 43·1 kg (average s.e.d. = 2·27, P < 0·001).The pattern of moult was described by changes in a subjectively assessed moult score, the proportion of follicles with brushes and staple length. The loss of brushes, indicating the start of the moult, began from the primary follicles on days 143, 131, 76, 150 and 129 (average s.e.d. = 13·5, P < 0001), and from the secondary follicles on days 141, 128, 104, 144 and 125 (average s.e.d. = 14·1, P = 0·053) for treatments L, M, H, SL and SAL respectively. The loss of brushes from primary and secondary follicles was completed on average, by days 194 and 206 of the experiment respectively, and there were no differences between treatments. Moult score and staple length data confirmed the conclusion that lowering the plane of nutrition delayed the start of the moult. No additional effect of fleece removal in the shorn treatments was observed.Changes in circulating levels of plasma prolactin, thyroxine, tri-iodothyronine, insulin, insulin-like growth factor-1 and growth hormone were related to seasonal changes in daylength and plane of nutrition. Their rôle in the control of the moult is discussed.Manipulation of the nutrition of cashmere goats in early spring has the potential to delay and increase the synchrony of fibre moult and to improve the efficiency of cashmere harvesting.

Comparative effects of food restriction, fasting, diabetes and thyroidectomy on growth hormone and thyrotropin gene expression in the rat pituitary

1995 ◽  
Vol 133 (1) ◽  
pp. 110-116 ◽  
Author(s):  
Manuela Rodriguez ◽  
Felipe Rodriguez ◽  
Trinidad Jolin ◽  
Pilar Santisteban
Keyword(s):  
Gene Expression ◽  
Growth Hormone ◽  
Food Restriction ◽  
Blot Hybridization ◽  
Northern Blot Hybridization ◽  
Mrna Levels ◽  
Restricted Feeding ◽  
Rat Pituitary ◽  
Ad Libitum ◽  
Ad Libitum Intake

Rodriguez M, Rodriguez F, Jolin T, Santisteban P. Comparative effects of food restriction, fasting, diabetes and thyroidectomy on growth hormone and thyrotropin gene expression in the rat pituitary. Eur J Endocrinol 1995;133:110–6. ISSN 0804–4643 To examine the molecular basis for the decreased pituitary growth hormone (GH) and thyrotropin (TSH) content during restricted feeding, fasting and diabetes, we measured steady-state levels of mRNA for TSH-α TSH-β and GH in the pituitary from normal rats either fed ad libitum (C), limited to 75%, 50% and 25% (FR75, FR50, FR25, respectively) of ad libitum intake, or deprived of food for 2 and 4 days (F2 and F4, respectively), and also in streptozotocin-diabetic (D) and D insulin-treated animals. The results from these experimental groups were compared with those in thyroidectomized (Tx) rats. Pituitary mRNA was quantified by Northern blot hybridization with cDNA probes specific for rat TSH-α, TSH-β and GH. Although changes in the pituitary GH mRNA during restricted feeding, fasting and diabetes were similar qualitatively to those induced by hypothyroidism, GH mRNA levels in Tx rats (> 10% of C values) were less than in the other experimental groups (p < 0.001). Pituitaries from FR50, FR25 and D rats also contained less GH mRNA than F2 and F4 animals (p < 0.05). Thyroidectomy resulted in a marked increase in both TSH-β and TSH-α mRNAs, the changes in TSH-β mRNA being greater than those in TSH-α mRNA. In contrast, FR50, FR2 5, F2, F4 and D rats exhibited a decrease in pituitary TSH-β mRNA (60%, 50%, 35%, 36% and 33%, respectively, of C values; p < 0.01–0.05) and in TSH-α mRNA levels (81%, 64%, 46%, 43% and 36%, respectively, of normal values; p < 0.02–0.05), TSH-β mRNA showing the greater changes. However, pituitaries from F2, F4 and D rats contained less TSH-β and TSH-α mRNA levels than FR50 and FR25 animals (p < 0.05). Insulin therapy partially restored the changes in mRNA for GH, TSH-β and TSH-α observed in D rats. In addition, the pituitary nuclear triiodothyronine in Tx, FR50, FR25, F2, F4 and D rats was reduced to 19%, 73%, 52%, 76%, 51% and 41%, respectively of C values (p < 0.05–0.001). These data suggest that GH, TSH-α and TSH-β gene expression are modulated by metabolic and/or endocrine changes accompanying restricted feeding, fasting and diabetes. P Santisteban, Instituto de Investigaciones Biomédicas, CSIC, Arturo Duperier 4, 28029 Madrid, Spain

Feed intake and competition in ewes on ad libitum or semi-restricted feeding of grass silage and hay

2012 ◽  
Vol 90 (11) ◽  
pp. 4014-4019 ◽  
Author(s):  
K. E. Bøe ◽  
A. M. Ottosen ◽  
I. L. Andersen
Keyword(s):  
Feed Intake ◽  
Restricted Feeding ◽  
Grass Silage ◽  
Ad Libitum

Seasonal changes in the germination responses of seeds of Veronica peregrina during burial, and ecological implications

1983 ◽  
Vol 61 (12) ◽  
pp. 3332-3336 ◽  
Author(s):  
Jerry M. Baskin ◽  
Carol C. Baskin
Keyword(s):  
Seasonal Changes ◽  
Natural Habitat ◽  
General Pattern ◽  
Late Summer ◽  
Early Spring ◽  
Late Winter ◽  
Seasonal Temperature ◽  
Light In August ◽  
Late Autumn ◽  
Response To Temperature

Seeds of Veronica peregrina collected from a field population in central Kentucky were buried in soil and exposed to seasonal temperature changes. Fresh seeds and those exhumed after 1–26 months were tested in light and darkness at five thermoperiods simulating those in the natural habitat from early spring through late autumn. Freshly matured seeds were dormant, but they came out of dormancy in June and July and germinated to 98–100% in light in August at thermoperiods of 20:10, 25:15, 30:15, and 35:20 °C. Seeds retained the ability to germinate to high percentages at these temperatures until late winter and spring, but they never germinated to high percentages in darkness. Thus, in the natural habitat in July and August germination is prevented only by darkness and (or) insufficient soil moisture. At simulated habitat temperatures, seeds germinated to 88–100% in March and April but to only 21–69% in May and June. Seeds incubated at 15:6 °C showed a decline in germination percentages in late summer and autumn and an increase during late autumn and winter. The same general pattern of seasonal changes in germination response to temperature occurred during the 2nd year of burial.

Sign in / Sign up

Export Citation Format

Share Document