Played a significantly greater proportion of embryos developing to neurulation than
Played a significantly greater proportion of embryos developing to neurulation than those from one priming (0.13 ?0.03; 0.06 ?0.04, respectively). It is important to note however, that overall the proportion of embryos developing to neurulation reported bySilla Reproductive Biology and Endocrinology 2011, 9:68 8 ofBrowne et al. [13] were substantially lower than those observed from the one priming treatment in the present study (see above). A plausible explanation for the diminished fertilisation capacity of oocytes obtained from females administered two priming injections in the present study, is oocyte over-ripening. Over-ripening is the process of aging of the oocytes retained within the coelomic cavity of the female PubMed ID: post ovulation [cf [47]]. Overripened oocytes are commonly reported in broodfish that do not oviposit spontaneously in captivity [47] and over-ripening is always associated with a substantial decrease in egg viability [48,49]. The terrestrial toadlet P. guentheri, as with other terrestrial myobatrachids, does not usually oviposit spontaneously following hormonal induction of ovulation in captivity (pers obs). Instead, physical stimulation of the oviduct through the process of stripping is required to obtain oocytes in this species. It is possible that females administered two priming injections of LHRHa ovulated earlier, and subsequently retained their oocytes longer, than those administered one priming injection, despite females in all treatments being stripped at a standard 10-11 hrs PA. This would lead to the over-ripening of oocytes in the two priming treatment, as indicated by the loss of fertilisation capacity (egg viability) and increase in the wet mass of oocytes [49].Received: 15 March 2011 Accepted: 20 May 2011 Published: 20 May 2011 References 1. Clulow J, Mahony M, Browne R, Pomering M, Clark A: Applications of assisted reproductive technologies (ART) to endangered anuran amphibians. In Declines and disappearances of Australian frogs. Edited by: Campbell A. Canberra: Environment Australia; 1999:219-225. 2. Kouba AJ, Vance CK: Applied Reproductive technologies and genetic resource banking for amphibian conservation. Repro Fertil Dev 2009, 21:719-737. 3. Galli-Mainini C: Pregnancy test using the male Batrachia. J Am Med Assoc 1948, 138:121-125. 4. Bhaduri JL, Bardhan NR: Male frogs and toads as test animals for early pregnancy and certain related conditions. Science 1949, 109:517-518. 5. Frazer JFD, Wohlzogen FX: The PubMed ID: estimation of chorionic gonandotrophin, using the male British Toad Bufo bufo. J Physiol 1951, 113:322-329. 6. Easley KA, Culley DD, Horseman ND, Penkala JE: Environmental influences on hormonally induced spermiation of the bullfrog, Rana catesbeiana. J Exp Zool 1979, 207:407-416. 7. Goncharov BF, Shubravy OI, Serbinova IA, Pristinamycin IA price Uteshev VK: The USSR programme for breeding amphibians, including rare and endangered species. Zoo Yearbk 1989, 28. 8. Waggener WL, Carroll EJ: A method for hormonal induction of sperm release in anurans (eight species) and in vitro fertilization in Lepidobatrachus species. Dev Growth Differ 1998, 40:19-25. 9. Sherman CDH, Uller T, Wapstra E, Olsson M: Within-population variation in ejaculate characteristics in a prolonged breeder, Peron’s tree frog, Litoria peronii. Naturwissenschaften 2008, 95:1055-1061. 10. Silla AJ: Effects of luteinizing hormone-releasing hormone and argininevasotocin on the sperm-release response of G ther’s Toadlet, Ps.

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