Rafetus swinhoei Update, May 2017

TSA and partners coordinate a third artificial insemination attempt of the Yangtze Giant Softshell Turtle in China

By Dr. Gerald Kuchling

Semen collection by electro-ejaculation and artificial insemination of the last pair of Yangtze Giant Softshell Turtle (Rafetus swinhoei) in China unfortunately did not produce any fertilized eggs in 2015 and 2016, therefore we continue to modify and improve the procedures. Since artificial insemination has never been attempted in any other softshell turtle, we must continue to learn through trial and error. In preparation for the new attempt in April 2017, at our request, Suzhou Zoo separated the male and the female in mid-October 2016 so that the male would not (due to his damaged penis) lose sperm through unsuccessful mating attempts during winter and early spring.

Staff from the Suzhou Zoo load the Rafetus pair for their move to the temporary habitat. Photo Credit: P. Calle, WCS

To complicate things, the Suzhou Zoo moved to a new location during 2016 and the Rafetus pair was the last animals remaining at the old zoo site. Demolition of the old zoo commenced in early 2017, however, a new appropriate Rafetus facility is not yet available at the new zoo site. For this reason, the pair had to be moved into a temporary pond/enclosure outside the zoo complex. In mid-March 2017, Dr. Gerald Kuchling (TSA) went to Suzhou to advise the zoo regarding the design of a temporary enclosure and to negotiate the possibility for a further attempt of artificial insemination prior to the turtles being moved. This eventually took place on 14 April 2017, in basically the only room left standing at the huge demolition site. After their recovery, on 16 April 2017, the turtles were moved to their new temporary pond.

Susanne Holtze (Institute for Zoo Biology and Wildlife Research), Gerald Kuchling (TSA), Thomas Hildebrandt (Institute for Zoo Biology and Wildlife Research), and Qui qi guan (Changsha Zoo veterinarian), carefully perform the procedure. Photo Credit: P. Calle, WCS

Several changes occurred regarding team members and procedures. Firstly, Professor Thomas Hildebrandt and Dr. Susanne Holtze (Department of Reproduction Management of the Leibniz Institute for Zoo & Wildlife Research in Berlin) agreed to team up for the procedure with Dr. Paul Calle (Wildlife Conservation Society), Dr. Kuchling (TSA), veterinarians from the Suzhou and Changsha Zoos, as well as representatives of WCS-China and the China Zoological Society. Dr’s. Hildebrandt and Holtze brought with them state-of-the-art equipment for artificial insemination that were not available during previous attempts. This included a flexible electro-ejaculation probe, a 3D-ultrasound system, and a battery-driven flexible video-chip endoscope with an integrated LED-light source and a working channel, allowing for the positioning of golden-tipped guide wires (normally used for bile ducts and vessels) through the cloaca. These wires are then used as guides to push insemination catheters into the oviducts. This less invasive and less risky method is preferable to insemination through coelioscopy, a method which we performed in 2016. Trials with various softshell turtles at Omaha’s Henry Doorly Zoo had demonstrated that, with the equipment then available to us, we could not do insemination directly into the oviducts through a cloacal approach.

The turtle pair bask in their temporary habitat. Photo Credit: P. Calle, WCS

The procedures of this April were again protracted. Due to the male’s heavily damaged penis, semen collection was again challenging and only a small amount of uncontaminated high-quality semen could be secured. Even with the state-of-the-art insemination equipment, the female had to be kept anaesthetized for over three hours before we managed to insert a catheter into one of the oviducts – confirming the problems with insemination through the cloaca detected during the trials last year. Thus, this year we only managed to deposit semen into one of the oviducts; the female could not remain anesthetized any longer.

Susanne Holtze (Institute for Zoo Biology and Wildlife Research), Lu Shunqing (Wildlife Conservation Society), Qui qi guan (Changsha Zoo veterinarian), Thomas Hildebrandt (Institute for Zoo Biology and Wildlife Research), and Gerald Kuchling (TSA), watch the procedure on the endoscope-linked monitor. Photo Credit: P. Calle, WCS

The team is planning some training trials with other species of softshell turtles to optimize this procedure prior for future artificial insemination attempts of the Yangtze Giant Softshell Turtle. Unfortunately, assisted reproductive technology remains our only hope to propagate a new generation of Rafetus. TSA President/CEO Rick Hudson said ‚ÄúThe TSA remains optimistic that this procedure will result in some fertile eggs, and we are especially grateful for the dedication of this remarkably talented reproductive team and their willingness to innovate in the face of such daunting odds. Never have the stakes been any higher.‚Äù