Gonadal and photoperiodic control of seasonal body weight changes in male voles

1984 ◽  
Vol 247 (1) ◽  
pp. R84-R88 ◽  
Author(s):  
J. Dark ◽  
I. Zucker
Keyword(s):  
Body Weight ◽  
Body Mass ◽  
Late Summer ◽  
Short Photoperiod ◽  
Late Winter ◽  
Weight Changes ◽  
Short Day ◽  
Long Day ◽  
Principal Factors ◽  
Gonadal Recrudescence

After 15 wk in a short photoperiod (10 h of light/day), adult male voles weighed 25% less and consumed 33% less food than did voles in a long photoperiod (14 h light/day). Neither body weight nor food intake differed among long- and short-day castrated voles. After 19 wk, castrated long-day voles weighed less than did intact animals. Voles reduced their body weight during the first 15 wk in the short photoperiod and increased their body mass during the succeeding 15 wk. Body mass of short-day voles was positively correlated with combined testes weight. Voles in the short photoperiod collected less nesting material than did their long-day counterparts at week 31. Pelage characteristics at week 32 were not affected by castration or by photoperiod. We conclude that the decreased body mass of male voles during the late summer, fall, and early winter reflects a decrease in circulating levels of testicular hormones; gonadal recrudescence and increased circulating androgen levels are in part responsible for the subsequent seasonal increase in body weight. Part of the increased body mass in late winter in field populations or in laboratory voles after 15 wk in the short photoperiod is independent of the resumption of gonadal activity. Fluctuations in neural and endocrine processes, rather than availability of food, are the principal factors underlying seasonal changes in energy balance.

Regional differences in fat pad responses to short days in Siberian hamsters

1989 ◽  
Vol 257 (6) ◽  
pp. R1533-R1540 ◽  
Author(s):  
T. J. Bartness ◽  
J. M. Hamilton ◽  
G. N. Wade ◽  
B. D. Goldman
Keyword(s):  
Body Weight ◽  
Body Fat ◽  
Subcutaneous Fat ◽  
Short Photoperiod ◽  
Fat Pad ◽  
Initial Exposure ◽  
Short Day ◽  
Siberian Hamsters ◽  
Long Day ◽  
Induced Changes

Siberian hamsters exhibit decreased body weight and fat after initial exposure to short photoperiods and increased body weight and fat after extended short photoperiod exposure. The purpose of the present experiments was to determine if uniform changes in white adipose tissue (WAT) pad weights and lipid metabolism correspond to these short photoperiod-induced changes in body fat. Carcass lipid content and testes and fat pad weights [retroperitoneal WAT (RWAT), epididymal WAT (EWAT), and inguinal and dorsal subcutaneous WAT, respectively] were decreased in male hamsters relative to their long day counterparts after 6 and 12 wk of short-day exposure. Moreover, EWAT and RWAT weight, EWAT specific lipoprotein lipase activity, and specific and total lipogenesis were disproportionately decreased relative to the subcutaneous fat pads. The changes in fat pad weight and metabolism were generally reversed coincident with the return to a long-day-like reproductive status after prolonged short-day exposure (24 and 30 wk). In a less detailed experiment, female Siberian hamsters had decreased body, fat pad, and uterine weights after 6 wk of short-day exposure; however, no fat pad-specific changes in weight were observed. The results of these experiments demonstrate that short-day-exposed male Siberian hamsters may be a useful model for examining mechanisms underlying fat pad-specific responses. In addition, gender appears to influence the pattern of short-day-induced lipid depletion in this species.

Control of torpor and body weight patterns by a seasonal timer in Siberian hamsters

1989 ◽  
Vol 257 (1) ◽  
pp. R142-R149 ◽  
Author(s):  
T. J. Bartness ◽  
J. A. Elliott ◽  
B. D. Goldman
Keyword(s):  
Body Weight ◽  
Food Intake ◽  
Implant Removal ◽  
Daily Torpor ◽  
Short Day ◽  
Siberian Hamsters ◽  
Long Day ◽  
Preparatory Phase ◽  
Pelage Color ◽  
Seasonal Responses

Two experiments were designed to assess whether the short-day-induced patterns of shallow daily torpor, body weight, and other seasonal responses (food intake and pelage pigmentation) exhibited by Siberian hamsters (Phodopus sungorus sungorus) are under the control of a "seasonal timekeeping mechanism" that is independent of reproductive status [testosterone, (T)]. We examined whether the patterning and expression of these seasonal responses were altered by decreases in serum T that accompany gonadal regression during the first 8 wk of short-day exposure (i.e., the "preparatory phase" of the torpor season) or by experimental increases in serum T after this phase. Short-day-housed, castrated hamsters bearing T implants had long-day levels of the hormone and did not exhibit torpor. Appropriate seasonal patterns and levels of torpor, body weight, pelage color stage, and food intake were exhibited after T implant removal although serum T was clamped to long-day levels during the preparatory phase. In animals that were gonad intact during the preparatory phase and were subsequently castrated and given T implants, torpor did not occur as long as the implants were in place. However, the patterns and levels of daily torpor, food intake, and body weight rapidly returned to appropriate seasonal values compared with the castrated, blank-implanted controls on T implant removal; these effects occurred whether the T implants were removed when torpor frequency was increasing, at its peak, or decreasing across the torpor season. T did not affect pelage color stage under any condition.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Body Mass Index and Body Weight Perception among a Population of Female Adolescents

2020 ◽  
Vol 8 (E) ◽  
pp. 308-312
Author(s):  
Siham Lghoul ◽  
Mohamed Loukid ◽  
Mohamed Kamal Hilali
Keyword(s):  
Body Mass Index ◽  
Body Weight ◽  
Body Mass ◽  
Weight Perception ◽  
Normal Weight ◽  
Female Adolescents ◽  
Weight Changes ◽  
Cross Sectional ◽  
Body Weight Perception ◽  
Physical Changes

BACKGROUND: Adolescence is associated with many physical changes, it is described as a period when body weight changes and is likely to become worrying for many adolescents. AIM: This study aims to evaluate associations between body weight perception and body mass index (BMI) among a population of female adolescents. METHODS: A cross-sectional school-based study was conducted from February to May 2017 among 12–19 years olds adolescents (n = 415) from high and middle school. BMI for age percentiles was calculated using the WHO AnthroPlus. Body weight perception was determined using an anonymous questionnaire. RESULTS: The prevalence of misconception of body weight was 60%. The prevalence of misconception was positively associated with the participants age (p < 0.001), the occurrence of menarche (p < 0.05), the increasing of BMI (p < 0.001), and with habits diet satisfaction (p < 0.05). Overweighed participants and who’s with normal weight were more likely to perceive their weight incorrectly (p < 0.05). Furthermore, approximately 2.9% of participants underestimated their true body weight and 57.1% overestimated their weight. However, all participants with underweight had correctly perceived their body weight. Logistic regression showed that predictor factors of misconception weight were participant’s age and BMI. CONCLUSION: It is recommended to improve healthy programs in schools aimed at preventing body weight perception and eating problems among adolescents.

scholarly journals Modification in body weight associated with antiepileptic drugs

2010 ◽  
Vol 68 (2) ◽  
pp. 277-281 ◽  
Author(s):  
Camilla N. De Gaspari ◽  
Carlos A.M. Guerreiro
Keyword(s):  
Physical Activity ◽  
Body Mass Index ◽  
Body Weight ◽  
Weight Gain ◽  
Antiepileptic Drugs ◽  
Body Mass ◽  
Dietary Habits ◽  
Weight Changes ◽  
Body Weight Changes ◽  
Epileptic Patients

Antiepileptic drugs (AED) may cause body weight changes. OBJECTIVE: To evaluate the dietary habits and body weight associated with AED in epileptic patients. METHOD: Sixty-six patients were subjected to two interviews, and had their weight and body mass index calculated and compared at both times, interval between six to eight months. RESULTS: It was observed that 59.1% showed weight gain. The patients who had no weight gain had a greater proportion of individuals who engaged in some form of physical activity. However, of the 45 patients who maintained their initial dietary and medication pattern, 75.6% recorded a weight gain. Weight gain was seen in 66.7% of patients on carbamazepine (n=18), 60% on valproate (n=5), 50% on carbamazepine+clobazam treatment (n=14), and 58.3% of patients on other(s) polytherapy (n=12). CONCLUSION: The patient should be alerted to possible weight gain, and should be advised about dieting and participating in regular physical activity.

Short-day-like body weight changes do not prevent fat pad compensation after lipectomy in Siberian hamsters

1997 ◽  
Vol 272 (1) ◽  
pp. R68-R77 ◽  
Author(s):  
M. M. Mauer ◽  
T. J. Bartness
Keyword(s):  
Body Weight ◽  
Food Restriction ◽  
Adipocyte Size ◽  
Weight Changes ◽  
Fat Pad ◽  
Body Weight Changes ◽  
Siberian Hamsters ◽  
Long Day ◽  
Long Duration ◽  
Short Days

Long-day (LD)-housed Siberian hamsters show compensatory increases in white adipose tissue (WAT) weight after lipectomy, whereas hamsters exposed to short days (SDs) for a long duration (22 wk) do not. We tested whether SD-induced body weight changes prevent fat pad compensation after lipectomy. In experiment 1, hamsters with lesions of the paraventricular nucleus of the hypothalamus (PVNx) rapidly increased body weight similarly to 22-wk SD-exposed hamsters. In experiment 2, LD-housed hamsters were food restricted for 22 wk and then pair fed with SD-housed hamsters for 12 wk to produce body weight changes mimicking those of ad libitum-fed SD-exposed animals. Epididymal WAT (EWAT) lipectomy (EWATx) of PVNx or food-restricted hamsters elicited compensatory increases in retroperitoneal and inguinal WAT (RWAT and IWAT) weights. Unlike other fat pads, EWAT was less affected by food restriction or PVNx than by SD exposure. In general, food restriction decreased adipocyte number, whereas SD exposure decreased adipocyte size. PVNx increased RWAT adipocyte size and IWAT adipocyte number. These results suggest that the lack of body fat compensation by EWATx hamsters exposed to SDs for a long duration is due to SD-associated responses other than body weight changes per se.

Changes in scaling of respiratory systems during the development of fishes

1988 ◽  
Vol 68 (3) ◽  
pp. 489-498 ◽  
Author(s):  
G. M. Hughes ◽  
N. K. Al-Kadhomiy
Keyword(s):  
Body Weight ◽  
Oxygen Consumption ◽  
Body Mass ◽  
Weight Changes ◽  
Body Weight Changes ◽  
Constant Change ◽  
Gill Area ◽  
The Relationship ◽  
Exchange Surface ◽  
Respiratory Area

Relationships between respiratory area, oxygen consumption, and body mass have been examined during the development of water- and air-breathing fish. It is concluded that there is at least one stage at which the slope of the relationship between log gill area and log body weight changes during fish development. This usually occurs in the weight range 0.05–1.0 g and is often associated with a distinct metamorphosis, but no common functional significance can be attached to them. However, the change in slope does not appear to be associated with a comparable inflexion in the corresponding relationship between body mass and oxygen consumption (routine). It seems probable that other surfaces are important during these transitions and that the total gas-exchange surface of the fish shows a more constant change throughout the life history. Further analyses of a wider range of species is required to test this hypothesis.

INFLUENCE OF BREED, BIRTH DATE, AGE AND BODY WEIGHT ON TESTICULAR MEASUREMENTS OF GROWING RAMS MAINTAINED IN A CONTROLLED ENVIRONMENT

1983 ◽  
Vol 63 (4) ◽  
pp. 835-847 ◽  
Author(s):  
J. N. B. SHRESTHA ◽  
P. S. FISER ◽  
G. A. LANGFORD ◽  
D. P. HEANEY
Keyword(s):  
Body Weight ◽  
Continuous Light ◽  
Skinfold Thickness ◽  
Day Length ◽  
Birth Date ◽  
Short Day ◽  
Scrotal Circumference ◽  
Long Day ◽  
Expanded Metal ◽  
Time Of Breeding

Testicular measurements, including scrotal circumference (SC), testis length (TL), testis width (TW), scrotal skinfold thickness (ST) and tonometer score (TS), and body weight (BW) were collected from 233 rams of three synthetic strains, Suffolk and Finnish Landrace breeds, at 6, 8 and 10 mo of age, at the time of first breeding in September 1981 (11–13 mo) and second breeding in April 1982 (18–21 mo). Rams were exposed to continuous light from birth to weaning (21 ± 3 days of age), to a long day-length (16 h light: 8 h darkness) from weaning to 6 mo and then to a short day-length (9 h light: 15 h darkness) to the time of breeding. Subsequently, the rams were exposed to 4 mo of long day-length followed by a 4 mo of short day-length. All rams were hysterectomy derived, housed indoors year-round on expanded metal floors in windowless barns and reared artificially. Breed, birth date, age of ram and body weight were found to have important effects (P < 0.05) on testicular measurements of growing rams, whereas, age of dam and litter size effects were absent (P > 0.05). In general, meat-type sire breeds (Strain 1 and Suffolk) had larger SC, TL, TW and BW when compared to the fecund sheep breeds (Finnish Landrace, Strains 2 and 3). Testicular measurements and BW of Finnsheep rams were smaller when compared to all other rams examined. The significance of breed and birth date effects varied as the ram progressed in age. Testicular measurements and BW increased with age of ram from 6 to 8 mo but TS showed no change. SC and BW increased substantially at 18–21 mo (April) compared to 11–13 mo (September), whereas TL, TW, ST and TS declined. SC, TL and TW were significantly correlated with each other at all ages. ST and TS were independent traits with no significant relationship to SC, TL, TW and BW. Key words: Sheep, testicular measurements, breed, birth date, age of ram, body weight

Effects of melatonin on long-day responses in short-day housed adult Siberian hamsters

1988 ◽  
Vol 255 (5) ◽  
pp. R823-R830 ◽  
Author(s):  
T. J. Bartness ◽  
B. D. Goldman
Keyword(s):  
Short Photoperiod ◽  
Serum Prolactin ◽  
Short Day ◽  
Siberian Hamsters ◽  
Long Day ◽  
Secretion Profile ◽  
Total Body Fat ◽  
Photoperiodic Responses ◽  
Epididymal White Adipose Tissue ◽  
Total Body

Testis growth is stimulated when short photoperiod-regressed Siberian hamsters are exposed to a lengthening photoperiod, an effect presumably mediated by the pineal gland through a decrease in the peak nocturnal duration of secretion of its hormone melatonin (MEL)(D. S. Carter and B. D. Goldman, Endocrinology 113: 1268-1273, 1983). We examined this stimulatory or "progonadal" effect of MEL in short photoperiod-regressed, adult male Siberian hamsters that were pinealectomized (PINX) and given timed daily subcutaneous 1) injections of MEL (1 or 10 micrograms/day) or saline or 2) infusions of MEL that were "long day-like" (4 h, 10 or 100 ng/day), "short day-like" (10 h, 10 ng/day), or control saline infusions (4 h/day). Photoregressed sham PINX hamsters were transferred to long days at this time. After 5 wk of treatment, 1-microgram MEL-injected hamsters and both groups of 4-h MEL-infused hamsters had stimulatory responses that mimicked those of the long-day-exposed, sham PINX group [i.e., increased testes, body, and epididymal white adipose tissue (EPIWAT) weights, total body fat, EPIWAT lipoprotein lipase activity, and serum prolactin and follicle-stimulating hormone levels]. These effects were not observed in 10-micrograms MEL- or saline-injected and 10-h MEL- or saline-infused hamsters. Thus the peak nocturnal duration of serum MEL is the critical parameter of the MEL secretion profile for stimulating a variety of photoperiodic responses when photoregressed hamsters are exposed to lengthening daylengths.

scholarly journals Effect of food on seasonal response in Indian weaver bird (Ploceus philippinus)

2014 ◽  
Vol 15 (3) ◽  
pp. 19-28
Author(s):  
Shikha Malik ◽  
Rohit Kumar Pandey ◽  
Sanjay Kumar Bhardwaj
Keyword(s):  
Body Mass ◽  
Food Group ◽  
The Body ◽  
Day Length ◽  
Plumage Color ◽  
Supplementary Food ◽  
Short Day ◽  
Long Day ◽  
Group 5 ◽  
Group 2

We investigated the effect of normal (adlib) and supplementary food on body mass, testes growth, moult and plumage color in Indian weaver birds. Birds intially were kept under natural day length (NDL) and then exposed to short day lengths (8 h light: 16 h darkness) for at least 2 weeks before being subjected to an experimental regime. They were divided into five groups (n=4 each), groups 1 and 2 were held under SDL (Short day length -8L: 16D), groups 3 and 4 were exposed to LDL (Long daylength-16L: 8D) and simultaneously group 5 held under natural day length, served as control. One group of SDL (Group 2) and LDL (group 3) as well as group 5 (NDL) were fed on grain with supplement proteinaceous food and groups 2 and 4 were fed on adlib food (grain) only. Observations on body mass, testis growth, bodymolt and plumage color were recorded bi weekly. A significant change in the body mass under both photoperiodic groups (SDL; group 2 and LDL; group 4), but the testicular growth was noticed on long day lengths (LDL: 16L: 8D) and control (NDL) group. However the supplement food modulated the testes growth, body molt, beak pigmentation and body plumage regeneration. Early feather regeneration was found in supplementary food group under long day length. It is suggested that the supplementary food, affects the timing of the development of secondary sexual characteristics.

Gonadal and photoperiodic influences on body mass regulation in adult male and female prairie voles

1996 ◽  
Vol 270 (5) ◽  
pp. R1013-R1018 ◽  
Author(s):  
L. J. Kriegsfeld ◽  
R. J. Nelson
Keyword(s):  
Body Mass ◽  
Mass Gain ◽  
The Body ◽  
Prairie Voles ◽  
Male And Female ◽  
Short Day ◽  
Body Mass Regulation ◽  
Long Day ◽  
Survival And Reproduction ◽  
Short Days

Nontropical animals commonly use the annual change in photoperiod to phase seasonal adjustments that promote survival and reproduction. To cope with the energetic requirements of winter, many rodents alter body mass in anticipation of winter. Photoperiodic adjustments are often mediated by the pineal hormone melatonin; melatonin can exert a primary effect on body mass or secondarily affect body mass by changing blood gonadal steroid levels. The present study sought to determine if prairie voles (Microtus ochrogaster) alter body mass in response to short photoperiods. The role of the gonads in body mass regulation was also assessed. In experiment 1, males housed in short days increased body mass at a greater rate than long-day animals. Gonadectomy enhanced the body mass gain in short-day voles. These data suggest that the gonads contribute to short photoperiod-induced changes in body mass in male voles. In experiment 2, females housed in short days increased body mass at a greater rate than long-day animals, regardless of whether the animals were ovariectomized. Ovariectomy did not affect body mass in either long- or short-day animals, suggesting that the ovaries do not contribute to photoperiod-mediated changes in body mass in female prairie voles. Taken together, these studies suggest that male and female prairie voles use photoperiodic information to time seasonal changes in body mass.

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