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Individual study: Effect of priming injections of luteinizing hormone-releasing hormone on spermiation and ovulation in Günther’s toadlet, Pseudophryne guentheri

Published source details

Silla A.J. (2011) Effect of priming injections of luteinizing hormone-releasing hormone on spermiation and ovulation in Günther’s toadlet, Pseudophryne guentheri. Reproductive Biology and Endocrinology, 9, 68-76


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Use artificial fertilization in captive breeding Amphibian Conservation

A randomized, replicated study in 2009 of captive Gϋnther’s toadlets Pseudophryne guentheri in Western Australia (Silla 2011) found that hormone treatment with one priming injection resulted in high artificial fertilization rates (91–100%), whereas eggs with zero or two priming treatments failed to fertilize. Twenty-four females were randomly assigned to three treatments: a single dose of 2 μ/g lutenizing hormone-releasing hormone-a in simplified amphibian Ringer solution, or a dose preceded by one or two priming injections of 0.4 μ/g lutenizing hormone-releasing hormone (one hour apart). Twenty eggs/female were fertilized with sperm from macerated testis of wild caught males in simplified amphibian Ringer solution.

 

Use hormone treatment to induce sperm and egg release during captive breeding Amphibian Conservation

A randomized, replicated, controlled study in 2009 of captive Gϋnther’s toadlets Pseudophryne guentheri in Western Australia (Silla 2011) found that hormone treatment successfully induced sperm and egg release. Proportions of males producing sperm with no, one or two priming injections of luteinizing hormone-releasing hormone (LHRHa) did not differ (100%), but were significantly higher than controls (25%). Amount of sperm produced decreased with priming treatments (none: 1.8 x 104; one: 0.6 x 104; two: 0.3 x 104). Sperm viability did not differ between hormone treatments (0.6–0.7 sperm/total) and was highest at 3 hours. Significantly higher numbers released eggs with one or two priming treatments (priming: 100%; none: 25%; control: 0%). The same was true for the number of eggs (priming: 217–220; none: 19; control: 0). Mass of eggs from two priming treatments was significantly greater than from no priming (0.007 vs 0.001 g; one priming: 0.006 g). Thirty-two wild collected males and females were randomly assigned to four treatments: a single dose of 2 μ/g LHRHa in simplified amphibian Ringer solution, or a dose preceded by one or two priming injections of 0.4 μ/g LHRHa (hour apart), or a control of 100 μ/g of simplified amphibian Ringer solution. Sperm release was tested at 3, 7 and 12 hours after treatment. Ovulation was tested at 10–11 hours.