Characteristics of first-antler growth in reindeer and their association with seasonal fluctuations in steroid and insulin-like growth factor 1 levels

1998 ◽  
Vol 76 (11) ◽  
pp. 2096-2102 ◽  
Author(s):  
J E Blake ◽  
J E Rowell ◽  
J M Suttie
Keyword(s):  
Growth Factor ◽  
Growth And Development ◽  
Rangifer Tarandus ◽  
Plasma Testosterone ◽  
Insulin Like Growth Factor ◽  
Seasonal Fluctuations ◽  
Testosterone Levels ◽  
Rangifer Tarandus Tarandus ◽  
Antler Growth ◽  
Measurable Growth

Growth and development of the pedicles and first antlers were monitored in seven reindeer (Rangifer tarandus tarandus) calves (three males, four females) from birth to 1 year of age. Calves were weighed, blood was sampled, and antler observations and (or) measurements were taken on the day of birth and days 2, 4, and 7 and then at weekly intervals for the remainder of the year. Prior to measurable growth, the frontal lateral crest was carefully palpated for evidence of pedicle initiation, starting on the day of birth. Calves were born between April 8 and 26, 1994. Pedicle initiation occurred in all reindeer by day 7. Velvet skin first appeared when calves were 4-6 weeks old, when estimated pedicle height was 3.5 ± 0.9 cm (mean ± SD). Antler growth in both sexes followed a sigmoidal pattern, producing a mean antler length of 33.5 ± 4.2 and 46.7 ± 13.8 cm in females and males, respectively. Antler growth was complete by week 18 in females and week 21 in males. Velvet cleaning was associated with a significant increase in plasma testosterone levels in males and estradiol-17beta (but not testosterone) levels in females. Insulin-like growth factor 1 levels were significantly higher in males than in females and were positively correlated with the period of most rapid antler growth in both sexes. Casting occurred between March 14 and April 17, when steroid levels were at a minimum, and was immediately followed by growth of the second antler.

scholarly journals Effect of testosterone on antler growth in yearling male reindeer

Rangifer ◽  
1983 ◽  
Vol 3 (2) ◽  
pp. 6 ◽  
Author(s):  
Morten Ryg
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Food Intake ◽  
Inverse Relationship ◽  
Rangifer Tarandus ◽  
Testosterone Levels ◽  
Rangifer Tarandus Tarandus ◽  
Antler Growth ◽  
Effect Of Treatment

<p>1. The effect of exogenous testosterone on ander growth in yearling male reindeer (Rangifer tarandus tarandus) was tested. 2. Testosterone (33 mg/kg) inhibited antler growth, and in one animal induced cleaning and subsequent casting of the antlers. This animal grew a new set of antlers, which were cleaned at the normal time. 3. During treatment, there was an inverse relationship between peak testosterone levels and antler growth rate. 4. There was no effect of treatment on body weight or food intake. 5. It is concluded that the effects of testosterone on antler growth are qualitatively the same in reindeer as in other deer. However, because high testosterone doses were necessary to produce effects, it is questionable whether this hormone normally is responsible for the cessation of antler growth in reindeer.</p><p>Virkningen av testosteron p&aring; gevirvekst hos ett&aring;rige reinbukker.</p><p>Abstract in Norwegian / Sammendrag: 1. Virkningen av testosteron p&aring; gevirvekst hos ett-&aring;rige reinbukker (Rangifer tarandus tarandus) ble unders&oslash;kt. 2. Testosteron (33 mg/kg) hemmet gevirveksten, og hos ett dyr f&oslash;rte behandlingen til at geviret ble feiet og deretter felt. Deretter vokste det ut ett nytt gevir, som ble feiet til vanlig tid. 3. Det var en negativ korrelasjon mellom maksimale testosteronniv&aring;er og gevirvekst under behandlingen. 4. Det var ingen effekt p&aring; forinntak eller vektutvikling. 5. Det blir konkludert med at virkningen av testosteron p&aring; gevirvekst er kvalitativt den samme hos rein som hos andre hjortedyr. Det er likevel tvilsomt om testosteron normalt er ansvarlig for avslutningen av gevirvekst hos rein, fordi store testosterondoser m&aring;tte til for &aring; f&aring; noen virkning.</p><p>Testosteronin vaikutus vuodenik&aring;isten urosporojen sarvien kasvuun.</p><p>Abstract in Finnish / Tiivistelm&auml;: 1. Tutkimuksessa seurattiin ruiskeena annetun testosteronin vaikutusta vuodenik&aring;isten urosporojen (Rangifer tarandus tarandus) sarvien kasvuun. 2. Testosteron! (33 mg/kg) hidasti sarvien kasvua, aiheuttaen yhdess&aring; el&aring;imess&aring; sarvien kelomisen ja pudottamisen. Talle el&aring;imelle kasvoi uudestaan sarvet, jotka se keloi normaaliin aikaan. 3. Testosteronin huipputaso veress&aring; oli k&aring;sittelyaikana k&aring;&aring;nt&aring;en verrannollinen sarvien kasvunopeuteen. 4. K&aring;sittely ei vaikuttanut el&aring;inten ruumiinpainoon eik&aring; niiden ruokahaluun. 5. Voidaan p&aring;&aring;tell&aring; testosteronin vaikutuksien sarvien kasvuun olevan porossa laadullisesti yht&aring;l&aring;iset kuin muissakin hirviel&aring;imiss&aring;. Koska vaikutuksen aikaansaamiseksi vaadittiin korkeita testosteroniannoksia, voidaan kuitenkin pit&aring;&aring; kyseenalaisena, onko kyseinen hormoni normaalisti vastuussa poronsarven kasvun keskeytymisest&aring;.</p>

Mild Calorie Restriction Does Not Affect Testosterone Levels and Testicular Gene Expression in Mutant Mice

2007 ◽  
Vol 232 (8) ◽  
pp. 1050-1063 ◽  
Author(s):  
Juliana S. Rocha ◽  
Michael S. Bonkowski ◽  
Luiz R. França ◽  
Andrzej Bartke
Keyword(s):  
Growth Factor ◽  
Calorie Restriction ◽  
Hormone Receptor ◽  
Reproductive Organs ◽  
Luteinizing Hormone Receptor ◽  
Calorie Intake ◽  
Testicular Function ◽  
Insulin Like Growth Factor ◽  
Somatotropic Axis ◽  
Testosterone Levels

The hypothalamic-pituitary-gonadal (HPG) axis and the somatotropic axis are influenced by nutritional factors. Calorie restriction (CR) extends lifespan but suppresses both the HPG and the somatotropic axes. Since most CR studies use a fairly severe (40%–60%) reduction of calorie intake, we hypothesized that a milder CR (20%) might not be deleterious to reproduction in male mice. To test this hypothesis, we evaluated the effects of 20% CR on testicular testosterone content and on testicular expression of genes that are relevant to testicular function and reproductive competence, including insulin-like growth factor-I, cytochrome P450 aromatase (Cyp19a1), androgen receptor, luteinizing hormone receptor, follicle-stimulating hormone receptor, cytochrome P450c17 and 3-β-hydroxysteroid dehydrogenase/isomerase. To relate CR effects to the activity of the somatotropic axis, we have used growth hormone–resistant GHR knockout mice as well as transgenic mice overexpressing GH. Mild CR did not affect testosterone levels in testis homogenates and had little effect on expression of the examined genes in the reproductive organs. Altered activity of the GH/insulin-like growth factor–1 axis had a major impact on the parameters analyzed. The results also suggest that expression of several key genes involved in the control of testicular function is preserved under conditions of mild CR and encourage speculation that mild regimens of CR can produce longevity benefits without impairing reproduction.

Biologic substances present in human colostrums demonstrate the evolution of this essential nutrient for growth and development: Insulin-like growth factor-I and prolactin

2005 ◽  
Vol 25 (2) ◽  
pp. 133-142 ◽  
Author(s):  
Maria Musumeci ◽  
Jacques Simporè ◽  
Alfonsina D'Agata ◽  
Lucia Malaguarnera ◽  
Cinzia Carrozza ◽  
...  
Keyword(s):  
Growth Factor ◽  
Growth And Development ◽  
Insulin Like Growth Factor ◽  
Factor I ◽  
Essential Nutrient ◽  
Growth Factor I

scholarly journals Normal growth and development in the absence of hepatic insulin-like growth factor I

1999 ◽  
Vol 96 (13) ◽  
pp. 7324-7329 ◽  
Author(s):  
S. Yakar ◽  
J.-L. Liu ◽  
B. Stannard ◽  
A. Butler ◽  
D. Accili ◽  
...  
Keyword(s):  
Growth Factor ◽  
Growth And Development ◽  
Normal Growth ◽  
Insulin Like Growth Factor ◽  
Factor I ◽  
Growth Factor I

Antler Growth in Roe Deer: Effects of Casting and Correlations with Growth Hormone and Insulin Like Growth Factor I

1992 ◽  
pp. 505-510 ◽  
Author(s):  
Dieter Schams ◽  
Dietrich Barth ◽  
Eva-Maria Heinze-Mutz ◽  
Gabriele Pflaum ◽  
Heinrich Karg
Keyword(s):  
Growth Hormone ◽  
Growth Factor ◽  
Roe Deer ◽  
Insulin Like Growth Factor ◽  
Factor I ◽  
Antler Growth ◽  
Growth Factor I

Seasonal patterns of growth, voluntary food intake and plasma concentrations of prolactin, insulin-like growth factor-1, LH and gonadal steroids in male and female pre-pubertal red deer (Cervus elaphus) reared in either natural photoperiod or constant daylength

1996 ◽  
Vol 62 (3) ◽  
pp. 605-613 ◽  
Author(s):  
C. L. Adam ◽  
C. E. Kyle ◽  
P. Young
Keyword(s):  
Growth Factor ◽  
Food Intake ◽  
Red Deer ◽  
Plasma Testosterone ◽  
Plasma Prolactin ◽  
Insulin Like Growth Factor ◽  
Male And Female ◽  
Natural Photoperiod ◽  
Lh Secretion ◽  
Voluntary Food Intake

AbstractRed deer calves were reared from birth to 16 months in either constant intermediate 12L: 12D daylength (ID) or in natural photoperiod (NP) (four males and four females per group) to investigate effects on the somatotropic and reproductive axes, and to compare responses between the seres. Measurements, starting from 3 months (September), were made each week of live weight (LW), voluntary food intake (VFI), plasma prolactin, plasma insulin-like growth factor-1 (IGF-1), and plasma progesterone (females), and every 2 months of pulsatile LH secretion, plasma testosterone (males), responses to exogenous GnRH, and antler development (males).Both sexes in ID compared with NP had significantly higher LW gain (males, P < 0·001; females, P < 0·01) and VFI (P < 0·001) between winter solstice (WS) and spring equinox (SE), and VFI between SE and summer solstice (SS) (males, P < 0·05; females P < 0·01). Both sexes had significantly lower plasma prolactin concentrations in ID than in NP (males, P < 0·05; females, P < 0·01) between SE and SS. However, plasma IGF-1 was only significantly altered in males, being significantly higher in ID than NP between WS and SE (P<0·01). ID and NP females showed no significant differences in pulsatile LH secretion nor in the timing of pubertal ovulation. However, ID compared with NP males at 10 months (just after SE) had higher LH and testosterone pulse frequencies (P < 0·01), and at 12 months (just before SS) had higher mean testosterone concentrations (P < 0·01) and testosterone response to GnRH challenge (P<0·001). ID antlers hardened earlier at 11 months than NP antlers at 14 months (P < 0·001).Thus ID compared with NP in both sexes prevented the winter reduction in growth and appetite and the summer elevation in prolactin secretion, and in males, but not in females, stimulated higher IGF-1 secretion in winter, an earlier increase in LH pulse frequency, and an earlier increase in gonadal steroid production. This study has therefore revealed some intriguing similarities and contrasts in the responses to photoperiod shown by young male and female deer.

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