Evaluation of endoscopic salpingectomy for sterilization of female Formosan macaques (Macaca cyclopis)

Abstract

We evaluated the safety and postsurgical outcomes of endoscopic salpingectomy for sterilization of female Formosan macaques (Macaca cyclopis) as a method of population control. Nineteen adult female Formosan macaques were included in our study. The fallopian tubes of each anesthetized macaque were cauterized and excised endoscopically using a 2.7-mm rigid endoscope system. We recorded the complications encountered, and objectively scored the amount of hemorrhage throughout the procedure. Postoperative ovarian function was evaluated by monitoring the serum levels of sex hormones in ten of the macaques for two ovarian cycles following the salpingectomy. Two to 13 months later, eight of the 19 macaques underwent laparoscopy for the objective evaluation of inflammation at the surgical sites on the fallopian tubes. No major anesthetic- or surgical-associated complications were observed in any of the macaques. The hormonal evaluation showed cyclic ovarian function after salpingectomy in all of the ten macaques examined, and the parameters were comparable to those of other macaque species. The long-term postoperative level of inflammation at the surgical site was minimal to low, and was lower than that reported for other tubal occlusion techniques used in macaques. The use of a 2.7-mm rigid endoscope for salpingectomy in macaques is safe and efficient, with fewer postoperative complications than comparable sterilization techniques.

Tubectomy of Pregnant and Non-pregnant Female Balinese Macaques (Macaca Fascicularis) With Post-operative Monitoring

“…Previous studies have shown various undesirable side effects associated with castration, ovariectomy or contraceptive agents in primates (41)(42)(43)(44)(45). Conversely, while impeding fecundation, vasectomy and tubectomy keep intact the steroid hormonal functions underpinning normal sexual activity (20,46). Preservation of the gonadal hormones represents the best option when sterilizing wild female macaques as it allows them to keep normal sexual and social behaviors in their group.…”

“…The technique we describe here is adapted from the endoscopic salpingectomy in wild macaques first demonstrated by P. Martelli in a DVD entitled “Endoscopic Tubectomy in Macaques” for a German company selling endoscopic equipment (Karl Storz-Endoskope) in 2009. Endoscopic salpingectomy has since widely been used for neutering campaigns in Formosan ( 20 ), rhesus ( 14 , 17 ) macaques and quite recently, on a chimpanzee ( Pan troglodytes ) ( 53 ).…”

“…While all previous reports combined coagulation of the oviducts followed by resection using endoscopic scissors of a section of each tube, that was removed from the abdominal cavity through the cannula ( 17 , 20 , 50 , 53 ), this study opted for thermocautery only. The oviduct is grasped and cauterized twice but no section is resected and removed.…”

“…This situation urges conducting systematic studies during and in the aftermath of the fertility control interventions to monitor the impacts, efficiency, and adequacy of the methods adopted with primates (10,19). As for laparoscopic tubectomy, clinical intra-, and postoperative evaluations have been described in a small number of rhesus (17) and Formosan macaques (M. cyclopis) (20) in captive settings, and more recently in a long term program in field conditions in free-ranging rhesus cross long-tailed macaques (14). However, the application of laparoscopic tubectomy to M. fascicularis in free-ranging settings, its clinical evaluation and possible modification to optimize the technique as well as a long-term post-surgery monitoring remain lacking and need to be documented.…”

Endoscopy and Endosurgery in Nonhuman Primates

“…13 Major complications included difficult entry into the abdominal cavity using the Veress needle, intraoperative hemorrhage, and inadvertent cauterization of uterus. Bleeding from the omentum as a result of Veress needle or trocar trauma has also been reported 13 SUMMARY Endoscopy in NHPs is of great value for disease diagnosis, minimally invasive surgery, and research studies. Primate-specific anesthesiology, case management, and surgical anatomy are important prerequisites before performing any endoscopic procedure.…”