Incubation Temperature and Yolk Steroids Regulate Hatching Synchrony in Calotes versicolor (Daud.)

V. Vani, Gopal M. Advi Rao, Laxmi S. Inamdar (Doddamani)

Abstract


The chronology of hatching behavior, hatching success and the significance of maternal yolk steroids (estradiol and testosterone) in hatching synchrony were studied in the lizard Calotes versicolor at male-producing (25.5 ± 0.5 and 34 ± 0.5°C), female-producing (23.5 ± 0.5 and 31.5 ± 0.5°C) and at high (35°C) temperatures. The results reveal that in a given clutch, the embryo that has utilized most of its yolk initiates the pipping behavior first. Hatching success as well as incubation period decreases with increase in incubation temperature and the temperatures from 23.5 ± 0.5°C to 31.5 ± 0.5°C are recorded as optimum viable range for the development and successful hatching of C. versicolor eggs. Hatching is highly synchronous in C. versicolor irrespective of incubating temperature, sex and clutch-to-clutch differences. Significance of maternal steroids in hatching pattern was studied at both male and female-producing temperatures. High interclutch variance, but low intraclutch variance in estradiol and testosterone concentrations found at oviposition as well as at hatching suggest their possible role in the synchronization of hatching by exhibiting similar magnitude of steroid profile within a clutch. It is observed that there is no sex based hatching synchrony in this species. The study indicates that temperature and steroids act synergistically and might play a role in synchronization of hatching in C. versicolor.

Keywords


incubation temperature; hatching behavior; hatching synchrony; estradiol; testosterone

Full Text:

PDF

References


Bobyn M. L. and Brooks R. J. (1994), «Interclutch and interpopulation variation in the effects of incubation conditions on sex, survival and growth of hatchling turtles (Chelydra serpentina)», J. Zool. Lond., 233, 233 – 257.

Bull J. J. (1980), «Sex determination in reptiles», Quart. Rev. Biol., 55, 3 – 21.

Crews D. and Bull J. J. (2008), «Some like it hot (and some don’t)», Nature, 451(31), 527 – 528.

Diamond A. W. (1976), «Breeding biology and conservation of hawksbill turtles, Eretmochelys imbricata L., on Cousin Island, Seychelles», Biol. Conserv., 9, 199 – 215.

Doddamani L. S. (1994), «Histoenzymological studies on the embryonic and posthatching development of the ovary in the tropical oviparous lizard, Calotes versicolor», J. Morphol., 221, 1 – 10.

Doddamani L. S. (2000), «Development of the adrenal gland in the tropical lizard, Calotes versicolor», Gen. Comp. Endocrinol., 117, 89 – 102.

Doddamani L. S. (2006), «Differentiation and development of testis in the oviparous lizard, Calotes versicolor», J. Exp. Zool., 305A, 299 – 308.

Du W. G., Shou L., and Liu J. K. (2003), «The effect of incubation temperature on egg survival, hatchling traits and embryonic use of energy in the blue-tailed skink, Eumeces elegans», Anim. Biol., 53(1), 27 – 36.

Elf P. K. (2003), «Yolk steroid hormones and sex determination in reptiles with TSD», Gen. Comp. Endocrinol., 132, 349 – 355.

Godley B. J., Broderick A. C., and Mrosovsky N. (2001), «Estimating hatchling sex ratios of loggerhead turtles in Cyprus from incubation durations», Mar. Ecol. Progr. Ser., 210, 195 – 201.

Hays G. C. and Speakman J. R. (1992), «The pattern of emergence by loggerhead turtle (Caretta caretta) hatchlings on Cephalonia, Greece», Herpetologica, 48, 396 – 401.

Hendrickson J. R. (1958), «The green turtle, Chelonia mydas (Linn.) in Malaya and Sarawak», Proc. Zool. Soc. Lond., 130, 455 – 535.

Houghton J. D. R. and Hays G. C. (2001), «Asynchronous emergence by loggerhead turtle (Caretta caretta) hatchlings», Naturwissenschaften, 88, 133 – 136.

Janzen F. J. and Paukstis G. L. (1991), «Environmental sex determination in reptiles-ecology, evolution, and experimental design», Quart. Rev. Biol., 66, 149 – 179.

Ji X. and Du W. G. (2001), «The effects of thermal and hydric environments on hatching success, embryonic use of energy and hatchling traits in a colubrid snake, Elaphe carinata», Comp. Biochem. Physiol., 129A, 461 – 471.

Kaska Y., Ilgac C., and Ozdemir A. (2006), «Sex ratio estimations of loggerhead sea turtle hatchlings by histological examination and nest temperatures at Fethiye beach, Turkey», Naturwissenschaften, 93, 338 – 343.

Matsuzawa Y., Sato K., Sakamoto W. W., and Bjorndal K. A. (2002), «Seasonal fluctuations in sand temperature: effects on the incubation period and mortality of loggerhead sea turtle (Caretta caretta) pre-emergent hatchlings in Minable», Jap. Mar. Biol., 140, 639 – 646.

Moran K. L., Bjorndal K. A., and Bolten A. B. (1999), «Effects of the thermal environment on the temporal pattern of emergence of hatchling loggerhead turtles Caretta caretta», Mar. Ecol. Progr. Ser., 189, 251 – 261.

Mrosovsky N., Baptistotte C., and Godfrey M. H. (1999), «Validation of incubation duration as an index of the sex ratio of hatchling sea turtles», Can. J. Zool., 77, 831 – 835.

Muthukkaruppan V. R., Kanakambika P., Manickavel V., and Veeraraghavan K. (1970), «Analysis of the development of the lizard, Calotes versicolor. I. A series of the normal stages in the embryonic development», J. Morphol., 130, 479 – 490.

Pieau C. (1996), «Temperature variation and sex determination in reptiles», BioEssays, 18, 19 – 26.

Pieau C., Dorizzi M., and Mercier N. R. (1999), «Temperature-dependent sex determination and gonadal differentiation in reptiles», C.M.L.S., 55, 887 – 900.

Radder R. S. and Shine R. (2007), «Sex-based hatching asynchrony in an oviparous lizard (Bassiana duperreyi, Scincidae)», Austr. Ecol., 32, 502 – 508.

Spencer R. J., Thompson M. B., and Banks P. B. (2001), «Hatch or wait? A dilemma in reptilian incubation», Oikos, 93, 401 – 406.

Schwabl H. (1993), «Yolk is a source of maternal testosterone for developing birds», Proc. Natl. Acad. Sci. USA, 90, 11446 – 11450.

Thompson M. B. and Speake B. K. (2002), «Energy and nutrient utilization by embryonic reptiles», Comp. Biochem. Physiol. A. Mol. Int. Physiol., 133, 529 – 538.

Van Damme R., Bauwens D., Brana F., and Verheyen R. F. (1992), «Incubation temperature differentially affects hatching time, egg survival, and hatching performance in the lizard, Podarcis muralis», Herpetologica, 48, 220 – 228.

Yao H. H.-C. and Capel B. (2005), «Temperature, genes, and sex: a comparative view of sex determination in Trachemys scripta and Mus musculus», J. Biochem., 138, 5 – 12.




DOI: https://doi.org/10.30906/1026-2296-2010-17-3-207-213

Refbacks

  • There are currently no refbacks.


You can subscribe to the print or electronic version of the journal on the site of EastView Company. If you have any questions, please write to the email sales@ivis.ru