Executive summary October, 2026 The tables and figures in this section summarize our key findings. Our recommendations for inducing turtles are based on this data. The recommendations can be found under the web-site heading “PIM instructional.” PIM instructional consists of a PDF that outlines our suggestions for a successful…
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In this section of the web-site we will provide you with the data that is the basis of our clinical recommendations. In general, the data will be presented in the order that the research took place. There will be a narrative accompanied by tables and photos to help make our findings as clear as possible. There will be 22 sections preceded by an executive summary. Section 21 is a list of the references we consulted for our work.
Simply click on the section below that you want to access.
The background of our research During a visit to John Legler’s lab at the University of Utah in 1977 we met a young graduate student named Jim Berry. I explained to Jim that we liked to keep hatchling turtles for a year or so, release them, and then replace them…
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Establishing a pattern for working with red eared sliders In the spring of 2008 we found ourselves at the Concordia Turtle Farm in Wildsville, Louisiana. Concordia is the largest turtle farm in the United States. It’s owned by the Evans family. They were very supportive of our goals and gave…
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Determining the techniques we would use Before we could begin to experiment with the different drugs that could induce oviposition we had to design a standard method of giving injections, a standard site for those injections and a consistent environment to contain the turtles. Environmental concerns included the possible need…
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Possible injection sites We had learned from earlier work that intraperitoneal injections were difficult to do. They were fraught with potential errors like injecting the drug into a solid organ, bowel or egg follicle. Drug absorption from the peritoneal cavity is very rapid because of the large surface area and,…
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Designing the best environment for oviposition Designing the best environment for oviposition We had learned in previous years how important it was to shield induced turtles from being frightened by movements around them. We used to suspend them over a wet towel in a closed closet to achieve this…
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Early work with various drugs and drug combinations The tables below show how poor the results were using oxytocin alone (Remember that “success” for us means that the turtle laid all its eggs after one injection). We pooled the intraperitoneal and subq results in the first table because they…
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Combinations of drugs we used The dramatic improvement in success shown in the table below (when we combined subq oxytocin and Lutalyse) led to a long series of experiments to determine the best proportions of each drug. A common side effect of Lutalyse is diarrhea. Because the incidence of diarrhea…
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Discovering the importance of prostaglandin F2 alpha (PGF-2) Carbetocin is a long acting analogue of oxytocin. It was difficult to obtain at the time we used it but it was worth the effort because we had an expectation that it would be much more effective than oxytocin. As the table…
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Some ideas that did not work Since the biochemical complexities of reptilian reproduction are poorly understood we decided to experiment with a few unlikely drugs to induce egg laying because it is known that different species of lizards use similar hormones/prostaglandins in different ways (Guillette et al. 1992) and that…
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Alpha-2 agonists and stressed turtles The table below illustrates that the alpha-2 agonist Domitor (medetomidine), when added to oxytocin + Lutalyse (PGF-2), seemed to be less effective with healthy RES than oxytocin + Lutalyse alone. However, that poor outcome was caused by the sequence of injection. Because we gave…
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Less common species we worked with on the turtle farm We had limited opportunities to work with small numbers of other North American turtle species at the Concordia Turtle Farm. Usually we were only able to induce a few of each species each year so the methods we used…
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Methods to determine the number of eggs in a clutch During our work with RES we depended on palpation to determine if the females were carrying eggs and how successful an induction had been. An induction was only classified as successful if no eggs were palpable afterwards. In 2009 we…
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Working with spiny softshell turtles Spiny softshells (SSS) are large and aggressive. They are also fast and hard to catch; even when using drift fences on a turtle farm! SSS are much too large to palpate for eggs so we had to x-ray each animal to determine how many…
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The drugs we tested on Spiny softshells We started out by using oxytocin alone to induce the SSS. We tried it at two dosage levels, after different holding periods, with a low success rate in all cases, as shown below. After trying oxytocin alone we ran a trial of…
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Side effects of drugs used with RES and SSS Oxytocin used on its own has two significant side effects. One side effect is that it interferes with the next ovulation in species that lay multiple clutches. That means there is often only one clutch per season where there might have…
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Repeating an induction after the initial induction failed Previous work had suggested we would get the best results with a re-induction if we held an animal for 3 days after the initial, failed induction. This was difficult because there was only limited space to hold the turtles, especially the SSS…
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Are there long term effects on reproductive behaviour after inducing every clutch of Red-eared sliders with Lutalyse for eleven years? Because we were running the experiments with Australian snake necks simultaneous with the evaluation of long term behavior of RES, and only had limited space in our elevated ponds,…
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Working with the Australian snake neck turtle The Eastern snake neck turtle is very different from any of the North American turtles we have worked with. It is an exclusive carnivore with forward facing eyes. It has a very long neck and a narrow head so it can…
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Results of others that used our methods Our research has focused on a relatively small number of species. If you read the previous section (section 19) about our experience with Australian snake necks or section 14 on soft shell turtles it’s clear that not all species respond the same…
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References The references here relate directly to the trials at the Concordia Turtle Farm. Additional references that focus on earlier work and reproductive physiology are listed as part of the section of this web-site labeled as “2007 article.” Alkindi, A.Y.A., Mahmoud, I.Y., Woller, M.J. and Plude, J.L. Oviductal…
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Acknowledgments We would like to thank Jesse, Avis and Davey Evans, the owners of the Concordia Turtle Farm in Wildsville, Louisiana, for their wonderful support during the years of our study. Their unflinching generosity, insight, and tolerance will always be deeply appreciated. They made our times at the Concordia Turtle…
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