Plasma steroids associated with seasonal reproductive changes in a multiclutched freshwater turtle, Sternotherus odoratus

McPherson, R; Boots, Larry R.; MacGregor, Robert; Marion, Ken R.

doi:10.1016/0016-6480(82)90179-4

Cited by 89 publications

(33 citation statements)

References 23 publications

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“…A complex dissociated reproductive pattern could be an adaptation to extreme environments, enabling the limitation of costly sexual behaviors to the periods when environmental conditions are favorable (Crews, 1998). The production of spermatozoids, under the control of testosterone, would be time-dissociated from sexual behaviors: different components of reproductive effort being distributed over time (Callard et al, 1976;Kuchling et al, 1981;Licht, 1982;McPherson et al, 1982;Kuchling, 1999). This would alleviate the costs of reproduction that would otherwise be a very intensive reproductive episode if both gametogenesis and mate searching occurred simultaneously.…”

Section: Dissociated Reproductive Patternsmentioning

confidence: 99%

Does testosterone influence activity budget in the male Greek tortoise (Testudo graeca graeca)?

Sereau

Lagarde

Bonnet

et al. 2010

General and Comparative Endocrinology

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Section: Dissociated Reproductive Patternsmentioning

confidence: 99%

Does testosterone influence activity budget in the male Greek tortoise (Testudo graeca graeca)?

Sereau

Lagarde

Bonnet

et al. 2010

General and Comparative Endocrinology

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“…DeWciencies of these types are especially widespread in ecto thermic vertebrates (Callard and Ho, 1980;Edwards and Jones, 2001a,b;Moore and Lindzey, 1992;Norris and Jones, 1987;Whittier and Tokarz, 1992). Subsequently, most stud ies reporting concentrations of plasma sex steroids in tem perate reptiles during winter months involve subjects held under semi-natural (Edwards and Jones, 2001a,b;Saint Girons et al, 1993) or laboratory (Schuett et al, 1997;Zaidan et al , 2003) conditions, and only several involve sub jects studied in nature (Cree et al, 1992;McPherson et al, 1982;Rooney et al, 2004;Tyrrell and Cree, 1998).…”

Section: Despite the Challenges Presented By Weld Studies ƒ Theymentioning

confidence: 99%

Winter profile of plasma sex steroid levels in free-living male western diamond-backed rattlesnakes, Crotalus atrox (Serpentes: Viperidae)

Schuett

Repp

Taylor

et al. 2006

General and Comparative Endocrinology

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Recent Weld studies on the reproductive ecology of western diamond-backed rattlesnakes (Crotalus atrox) from populations in southern Ari typically inaccessible, but in southern Arizona, where environmental conditions are typically mild during winter, adult males frequently bask at or near the entrances of communal dens. Basking activity, therefore, oVers a unique logistical opportunity to assess the complete annual proWle of plasma sex steroid levels in males of a temperate reptile in nature. From November to February, we measured levels of plasma T, DHT, and E2 in adult male C. atrox that were located basking at communal dens. Additionally, cloacal, core body, and ambient air temperatures were obtained to investigate potential relationships between body temperatures and levels of sex steroids. Mean levels of T, DHT, and E2 were rela tively high, and the concentration hierarchy was T > DHT > E2. Mean levels of T, DHT, and E2 showed no signiWcant variation across the four months of sampling; however, E2 levels decreased progressively. In the annul cycle, sex steroid levels during winter were not basal when com pared to values obtained during the active season. Mean cloacal temperatures of basking males were signiWcantly higher than core body tem peratures of non-basking males (inside dens) from November-December, and in February, which suggests that one function of winter basking is to elevate body temperatures. Steroid levels, nonetheless, were not signiWcantly correlated with cloacal temperatures. We suggest that future Weld studies of male C. atrox should: (a) investigate sex steroid levels in non-basking individuals and (b) test whether elevated levels of sex ste roids during winter facilitate the large increases that occur in early spring, which are coincident with the second mating season. Our Wndings on the reproductive biology of C. atrox and other viperids are discussed in the context of the associated-dissociated model of reproduction.

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“…Squamate CL also secrete estradiol-17P and testosterone, although the major secretory product appears to be progesterone (Yaron, 1972b;Arslan et al, 1978). The pattern of luteal secretion is quite variable among the different reptilian species examined (Callard and Lance, 1977;Lance and Callard, 1978;Licht, 1982;McPherson et al, 1982). This variation is understandable considering the different reproductive strategies exhibited by reptiles.…”

mentioning

confidence: 91%

Luteal morphology, atresia, and plasma progesterone concentrations during the reproductive cycle of two oviparous lizards, Crotaphytus collaris and Eumeces obsoletus

Fox

Guillette

1987

Am. J. Anat.

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From ovulation to oviposition, the corpora lutea of the oviparous lizards Crotaphytus collaris and Eumeces obsoletus exhibit three stages of luteal development: 1) luteogenesis, 2) luteal maturity, and 3) luteal regression. Each stage exhibits distinct characteristics, involving changes in: 1) luteal volume, 2) nuclear diameter of cells within the luteal cell mass, and 3) thecal development. Plasma progesterone concentration is greatest during luteogenesis and is positively correlated with ovarian atresia, although atresia occurred throughout the period of gravidity. These data suggest that in these two species, the corpora lutea secrete high amounts of progesterone immediately following ovulation and exhibit morphologically distinct stages of growth and regression.

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Plasma steroids associated with seasonal reproductive changes in a multiclutched freshwater turtle, Sternotherus odoratus

Cited by 89 publications

References 23 publications

Does testosterone influence activity budget in the male Greek tortoise (Testudo graeca graeca)?

Does testosterone influence activity budget in the male Greek tortoise (Testudo graeca graeca)?

Winter profile of plasma sex steroid levels in free-living male western diamond-backed rattlesnakes, Crotalus atrox (Serpentes: Viperidae)

Luteal morphology, atresia, and plasma progesterone concentrations during the reproductive cycle of two oviparous lizards, Crotaphytus collaris and Eumeces obsoletus

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