1
|
Lind CM, Moore IT, Vernasco BJ, Farrell TM. Seasonal testosterone and corticosterone patterns in relation to body condition and reproduction in a subtropical pitviper, Sistrurus miliarius. Gen Comp Endocrinol 2018; 267:51-58. [PMID: 29807034 DOI: 10.1016/j.ygcen.2018.05.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 04/17/2018] [Accepted: 05/25/2018] [Indexed: 11/26/2022]
Abstract
Seasonal constraints on the timing and intensity of reproductive events shape observed variation in life history strategies across latitudes. Selection acts on the endocrine mechanisms that underlie reproductive investment. It is therefore important to examine the seasonal relationship between hormones and reproduction in geographically and phylogenetically diverse taxa. Snakes have proven to be a valuable model in investigations of seasonal hormone production and behavior in field-active vertebrates, but most research has focused on temperate populations from highly seasonal environments. To reduce this bias, we provide a description of the seasonal relationships among testosterone, corticosterone, body condition, and reproductive behavior in a subtropical population of Pygmy Rattlesnakes, Sistrurus miliarius. In central Florida, Sistrurus miliarius exhibits a prolonged breeding season (September-January) compared to most temperate zone snakes. Despite the extended breeding season, the pattern of testosterone in the population was highly seasonal and very similar to temperate pitvipers with a shorter mating season. Testosterone declined steadily through the mating season, but males sampled while engaging in mating behaviors had higher testosterone compared to solitary males throughout the mating season. Testosterone was negatively related to corticosterone throughout the breeding season and during times of year when the gonads were presumed to be quiescent and no mating behavior was observed. Testosterone was positively related to individual body condition both within and outside of the breeding season. A review of the literature reveals no consistent pattern regarding the relationship between corticosterone and testosterone in snakes, but suggests that the condition-dependence of steroid production may be consistent across snake taxa.
Collapse
Affiliation(s)
- Craig M Lind
- Department of Biology, Stetson University, Deland, FL 32723, USA; Department of Natural Sciences and Mathematics, Stockton University, Galloway, NJ 08201, USA.
| | - Ignacio T Moore
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Ben J Vernasco
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | | |
Collapse
|
2
|
Graham SP, Fielman KT, Mendonça MT. Thermal performance and acclimatization of a component of snake (Agkistrodon piscivorus) innate immunity. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2017; 327:351-357. [DOI: 10.1002/jez.2083] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 06/22/2017] [Accepted: 06/26/2017] [Indexed: 11/07/2022]
Affiliation(s)
| | - Kevin T. Fielman
- Department of Biological Sciences; Auburn University; Auburn AL USA
| | - Mary T. Mendonça
- Department of Biological Sciences; Auburn University; Auburn AL USA
| |
Collapse
|
3
|
Safdarian P, Todehdehghanb F, Hojatia V, Shiravi A. Seasonal changes in the testicular activity of the Iranian Mountain Viper, Montivipera albicornuta (Nilson & Andrén, 1985) (Reptilia: Viperidae). ZOOLOGY IN THE MIDDLE EAST 2016. [DOI: 10.1080/09397140.2016.1144284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Parvaneh Safdarian
- Department of Biology, Damghan Branch, Islamic Azad University, Damghan, Iran
| | - Fatemeh Todehdehghanb
- Venomous Animals & Antivenin Production Department, Razi Vaccine and Serum Research Institute, Hesarak, Karaj, Iran
| | - Vida Hojatia
- Department of Biology, Damghan Branch, Islamic Azad University, Damghan, Iran
| | - Abdolhossein Shiravi
- Venomous Animals & Antivenin Production Department, Razi Vaccine and Serum Research Institute, Hesarak, Karaj, Iran
| |
Collapse
|
4
|
Smith CF, Schuett GW, Amarello M. Male mating success in a North American pitviper: influence of body size, testosterone, and spatial metrics. Biol J Linn Soc Lond 2015. [DOI: 10.1111/bij.12490] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Charles F. Smith
- Department of Ecology and Evolutionary Biology; The University of Connecticut; 75 N Eagle Road Unit 3043 Storrs CT 06269-3043 USA
- Department of Biology; Wofford College; 429 North Church Street Spartanburg SC 29303 USA
- The Copperhead Institute; P.O. Box 6755 Spartanburg SC 29304 USA
- Chiricahua Desert Museum; P.O. Box 376 Rodeo NM 88056 USA
| | - Gordon W. Schuett
- The Copperhead Institute; P.O. Box 6755 Spartanburg SC 29304 USA
- Chiricahua Desert Museum; P.O. Box 376 Rodeo NM 88056 USA
- Department of Biology and Center for Behavioural Neuroscience; Georgia State University; 33 Gilmer Street, S. E., Unit 8 Atlanta GA 30303 USA
| | - Melissa Amarello
- The Copperhead Institute; P.O. Box 6755 Spartanburg SC 29304 USA
- Advocates for Snake Preservation (A.S.P.); P.O. Box 40493 Tucson AZ 85717 USA
| |
Collapse
|
5
|
Lind CM, Beaupre SJ. Natural variation in steroid hormone profiles of male Timber Rattlesnakes, Crotalus horridus, in northwest Arkansas. Gen Comp Endocrinol 2014; 206:72-9. [PMID: 24997417 DOI: 10.1016/j.ygcen.2014.06.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 06/18/2014] [Accepted: 06/20/2014] [Indexed: 11/27/2022]
Abstract
We describe the seasonal profile of circulating steroid hormones (testosterone and corticosterone) in relation to the breeding season in free ranging male Timber Rattlesnakes, Crotalus horridus, over the course of three active seasons. In addition, we examine variation in steroid concentrations across years and in relation to body condition. We found that seasonal profiles of plasma testosterone were different compared to other crotalines with similar mating patterns. Concentrations of testosterone were elevated above baseline in the three months leading up to the single late summer breeding season. Testosterone peaked in July at the onset of the breeding season and dropped to baseline during the peak months of breeding (August and September). Testosterone concentrations also varied annually. Although the exact cause of annual variation could not be established, our results indicate that weather patterns may have driven observed differences. Testosterone concentrations were positively related to body condition, indicating that testosterone production is modulated according to energetic status (particularly in the two months prior to the breeding season). Corticosterone did not vary seasonally or with any measured variable, a result similar to other studied crotalines. Our results highlight the importance of long-term descriptive studies of the regulatory mechanisms that underlie behavior and physiology in diverse taxa, as these mechanisms can vary greatly within and among populations and are valuable in elucidating the intrinsic and extrinsic sources of such variation.
Collapse
Affiliation(s)
- Craig M Lind
- Department of Biological Sciences, University of Arkansas, 850 West Dickson Street, SCEN 601, Fayetteville, AR 72701, USA.
| | - Steven J Beaupre
- Department of Biological Sciences, University of Arkansas, 850 West Dickson Street, SCEN 601, Fayetteville, AR 72701, USA
| |
Collapse
|
6
|
Sivan J, Kam M, Hadad S, Allan Degen A, Rozenboim I, Rosenstrauch A. Reproductive cycle of free-living male Saharan sand vipers, Cerastes vipera (Viperidae) in the Negev desert, Israel. Gen Comp Endocrinol 2012; 179:241-7. [PMID: 22967959 DOI: 10.1016/j.ygcen.2012.08.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2012] [Revised: 08/20/2012] [Accepted: 08/23/2012] [Indexed: 10/27/2022]
Abstract
The Saharan sand viper, Cerastes vipera (Linnaeus, 1758), is distributed in all Saharan countries, being confined to sand and dune systems. This relatively small snake, up to 35 cm, is nocturnal, is active from spring to autumn (April to October) and hibernates during the winter (November to March). We predicted that C. vipera would have peak plasma testosterone concentration at mating and that the vas deferens would contain abundant spermatozoa at that time. To test our predictions, we collected information on the time of mating and measured monthly testosterone concentration, testes size and testicular activity in free-living male C. vipera during its active period from April to October. Mating occurred only during spring. The pattern of plasma testosterone concentration, testes volume, seminiferous tubule diameter and spermatogenesis all followed the general pattern of high values in autumn and spring and low values in early summer. Our predictions were partially supported. There was a high plasma testosterone concentration at mating in spring and the vas deferens contained abundant spermatozoa, as predicted, but there was also a high plasma testosterone concentration in autumn without mating. We concluded that: (1) males are both aestival in that they produce spermatozoa in autumn, which they store over the winter hibernation period, and vernal in that they produce spermatozoa in spring prior to mating; (2) matings are associated with spermatogenesis; and (3) the high plasma testosterone concentration is concomitant with both matings and spermatogenesis in spring and with spermatogenesis in autumn. We propose that C. vipera has a single peak of testicular activity and plasma testosterone concentration which start in autumn and end in spring. We also propose that spermatogenesis is prior to spring mating and, consequently, is prenuptial.
Collapse
Affiliation(s)
- Jaim Sivan
- Department of Life Sciences, Academic College Achva, M.P. Shikmim, Israel
| | | | | | | | | | | |
Collapse
|
7
|
Smith CF, Schuett GW, Hoss SK. Reproduction in female copperhead snakes (Agkistrodon contortrix): plasma steroid profiles during gestation and post-birth periods. Zoolog Sci 2012; 29:273-9. [PMID: 22468838 DOI: 10.2108/zsj.29.273] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We investigated levels of plasma progesterone (P4), 17β-estradiol (E2), testosterone (T), and corticosterone (CORT) during gestation and post-birth periods in wild-collected female copperhead snakes (Viperidae; Agkistrodon contortrix). We also sought to determine whether CORT levels at (or near) birth dramatically increase and were correlated with duration of labor and litter size. Specifically, pregnant subjects (N = 14) were collected during early- to mid-gestation, held in the laboratory, and repeatedly bled to obtain plasma for steroid analyses. Progesterone showed significant changes during gestation, with the highest levels at the onset of sampling (circa 50 days prior to birth); P4 progressively declined up to parturition, and basal levels were observed thereafter. At the onset of sampling, E2 was at peak levels and fell sharply at circa 30 days prior to birth, a trend observed throughout the post-birth sampling period. Throughout the entire sampling period, T was undetectable. Although CORT showed no significant changes during gestation and several days following parturition, there was a highly significant peak at the time of birth. Our findings mirror the results of previous studies on pregnancy and steroid hormones of other live-bearing snakes, lizards, and mammals. As expected, there was a significant relationship between duration of labor and litter size; however, although levels of CORT did not achieve significance, there was a positive trend with litter size. We suggest that elevation of CORT at birth is involved in the mobilization and regulation of energy stores necessary for the physiological process of parturition and as a possible mechanism to trigger birth.
Collapse
Affiliation(s)
- Charles F Smith
- Department of Ecology and Evolutionary Biology, The University of Connecticut, Storrs, Connecticut 06269-3043, USA.
| | | | | |
Collapse
|
8
|
Reproduction in Male Crotalus adamanteus Beauvois
(Eastern Diamond-Backed Rattlesnake): Relationship of Plasma Testosterone to Testis and Kidney Dimensions and the Mating Season. SOUTHEAST NAT 2011. [DOI: 10.1656/058.010.0108] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
9
|
Lind CM, Husak JF, Eikenaar C, Moore IT, Taylor EN. The relationship between plasma steroid hormone concentrations and the reproductive cycle in the Northern Pacific rattlesnake, Crotalus oreganus. Gen Comp Endocrinol 2010; 166:590-9. [PMID: 20138180 DOI: 10.1016/j.ygcen.2010.01.026] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2009] [Revised: 11/15/2009] [Accepted: 01/31/2010] [Indexed: 11/22/2022]
Abstract
We describe the reproductive cycle of Northern Pacific rattlesnakes (Crotalus oreganus) by quantifying steroid hormone concentrations and observing reproductive behaviors in free-ranging individuals. Additionally, we examined reproductive tissues from museum specimens. Plasma steroid hormone concentrations were quantified for both male and female snakes throughout the active season (March-October). We measured testosterone (T), 5alpha-dihydrotestosterone (DHT), and corticosterone (B) concentrations in both sexes and 17beta-estradiol (E2) and progesterone (P) in females only. We observed reproductive behaviors (e.g., consortship, courtship, and copulation) in the field and measured testis and follicle size in male and female snakes from museum collections to relate steroid hormone concentrations to the timing of reproductive events. Our study revealed that C. oreganus in central California exhibits a bimodal pattern of breeding, with most mating behavior occurring in the spring and some incidences of mating behavior observed in late summer/fall. Each breeding period corresponded with elevated androgen (T or DHT) levels in males. Testes were regressed in the spring when the majority of reproductive behavior was observed in this population, and they reached peak volume in August and September during spermatogenesis. Although we did not detect seasonal variation in female hormone concentrations, some females had high E2 in the spring and fall, coincident with mating and with increased follicle size (indicating vitellogenesis) in museum specimens. Females with high E2 concentrations also had high T and DHT concentrations. Corticosterone concentrations in males and females were not related either to time of year or to concentrations of any other hormones quantified. Progesterone concentrations in females also did not vary seasonally, but this likely reflected sampling bias as females tended to be underground, and thus unobtainable, in summer months when P would be expected to be elevated during gestation. In females, P was positively correlated with T and DHT, and E2 was positively correlated with T.
Collapse
Affiliation(s)
- Craig M Lind
- Dept. Biological Sciences, California Polytechnic State University, San Luis Obispo, CA 93407-0401, USA.
| | | | | | | | | |
Collapse
|
10
|
Smith CF, Schuett GW, Schwenk K. Relationship of plasma sex steroids to the mating season of copperheads at the north-eastern extreme of their range. J Zool (1987) 2010. [DOI: 10.1111/j.1469-7998.2009.00669.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
11
|
Lutterschmidt WI, Lutterschmidt DI, Mason RT, Reinert HK. Seasonal variation in hormonal responses of timber rattlesnakes (Crotalus horridus) to reproductive and environmental stressors. J Comp Physiol B 2009; 179:747-57. [DOI: 10.1007/s00360-009-0356-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Revised: 03/04/2009] [Accepted: 03/19/2009] [Indexed: 11/29/2022]
|
12
|
Graham SP, Earley RL, Hoss SK, Schuett GW, Grober MS. The reproductive biology of male cottonmouths (Agkistrodon piscivorus): do plasma steroid hormones predict the mating season? Gen Comp Endocrinol 2008; 159:226-35. [PMID: 18823979 DOI: 10.1016/j.ygcen.2008.09.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2008] [Revised: 08/27/2008] [Accepted: 09/09/2008] [Indexed: 11/25/2022]
Abstract
To better understand the proximate causation of the two major types of mating seasons described for North American pitvipers, we conducted a field study of the cottonmouth (Agkistrodon piscivorus) in Georgia from September 2003 to May 2005 that included an extensive observational regime and collection of tissues for behavioral, anatomical, histological, and hormone analysis. Enzyme immunoassays (EIA) of plasma samples and standard histological procedures were conducted on reproductive tissues. Evidence from the annual testosterone (T) and sexual segment of the kidney (SSK) cycle and their relationship to the spermatogenic cycle provide correlative evidence of a unimodal mating pattern in this species of pitviper, as these variables consistently predict the mating season in all snake species previously examined under natural conditions. In most reptiles studied to date, high plasma levels of T and corticosterone (CORT) coincide during the mating period, making the cottonmouth an exception to this trend; we suggest two possible explanations for increased CORT during spring (regulation of a spring basking period), and decreased CORT during summer (avoiding reproductive behavioral inhibition), in this species.
Collapse
Affiliation(s)
- Sean P Graham
- Center for Behavioral Neuroscience, Georgia State University, 33 Gilmer Street, S.E., Unit 8, Atlanta, GA 30303-3088, USA.
| | | | | | | | | |
Collapse
|
13
|
Repp RA, Schuett GW. Western Diamond-Backed Rattlesnakes, Crotalus atrox (Serpentes: Viperidae), Gain Water by Harvesting and Drinking Rain, Sleet, and Snow. SOUTHWEST NAT 2008. [DOI: 10.1894/0038-4909(2008)53[108:wdrcas]2.0.co;2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
14
|
Benner SL, Woodley SK. The reproductive pattern of male dusky salamanders (genus Desmognathus) is neither associated nor dissociated. Horm Behav 2007; 51:542-7. [PMID: 17382330 DOI: 10.1016/j.yhbeh.2007.02.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Revised: 02/14/2007] [Accepted: 02/15/2007] [Indexed: 11/21/2022]
Abstract
Many seasonally breeding vertebrate species have an associated reproductive pattern: mating behavior, gonadal activity, and peak circulating androgen levels occur simultaneously. In these species, androgens influence the expression of male mating behavior. Other species have a dissociated reproductive pattern: mating behavior occurs at a different time than peak gonadal activity. In such species, it is hypothesized that mating behavior is not dependent on androgen levels [Crews, D., 1984. Gamete production, sex hormone secretion, and mating behavior uncoupled. Horm. Behav. 18, 22-28]. The salamander Desmognathus ochrophaeus mates in the spring and fall while spermatogenesis occurs during the summer, suggesting that it has a dissociated reproductive pattern and that androgens do not mediate mating behavior. To assess whether mating behavior is regulated by gonadal androgens, we castrated males to reduce endogenous androgens and implanted testosterone propionate (TP) to restore androgen levels. Castrated males mated significantly less than did control males. Castrated males given TP mated as much as control males. Compared to controls, circulating androgen levels (both testosterone (T) and dihydrotestosterone (DHT)) were reduced in castrated males and elevated in castrated males given TP implants. We also found that plasma corticosterone (CORT) levels were strongly and positively correlated with T levels. Together, these data indicate that, although spermatogenesis is dissociated in time from mating behavior, androgens are associated with the expression of mating. Thus, the associated-dissociated dichotomy does not adequately describe the reproductive pattern of D. ochrophaeus. We discuss the limitations of the associated-dissociated framework in clarifying hormone-behavior relationships in reptiles and amphibians.
Collapse
Affiliation(s)
- Stacey L Benner
- Department of Biological Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282, USA
| | | |
Collapse
|