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

Laparoscopic Salpingectomy and Vasectomy to Inhibit Fertility in Free-Ranging Nutrias (Myocastor coypus)

The nutria (Myocastor coypus), an invasive alien species, is widely spread in Europe. Pursuant to regulation (EU) no. 1143/2014, the nutria is subject to management programs to reduce its spread. Surgical fertility control is considered an acceptable method, particularly in urban circumstances, avoiding euthanasia. To maintain the hormonal patterns and the social and behavioral dynamics, surgical infertilization preserving the gonads (i.e., salpingectomy and vasectomy) is recommended. Mini-invasive surgery is an eligible choice when dealing with wildlife, allowing reduced captivation time. For these reasons, 77 free-ranging nutrias, captured in urban nuclei in Italy, underwent infertilization under general anesthesia; laparoscopic salpingectomy and vasectomy were performed on 32 animals and traditional surgery on the remainder, leaving the gonads in place. A three-port technique was used, with two paramedian trocars (5 mm) for the instruments and a median one for the telescope. Ablation was obtained through Onemytis® plasma device, allowing a rapid surgical time with no need to place visceral sutures; the skin was surgically closed. After recovery, the animals were released, and no overt complications were noted. No modification of the behavioral patterns was noted, and the population decreased during the following months.

Use of Laryngeal Mask and Anesthetic Management in Hamadryas Baboons (Papio hamadryas) Undergoing Laparoscopic Salpingectomy-A Case Series

The study aims to describe the anesthetic and airway management of baboons (Papio hamadryas) undergoing laparoscopic salpingectomy with a laryngeal mask airway (LMA) device. Eleven baboons received tiletamine-zolazepam and medetomidine; anesthesia was induced with propofol. An LMA was positioned for oxygen and isoflurane administration in spontaneous respiration. Heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR), end tidal carbon dioxide (EtCO₂), minute volume (MV), and peripheral hemoglobin oxygen saturation (SpO₂) were recorded before (PREPP) and immediately after abdomen insufflation (PP1), at 10 (PP2), 20 (PP3), and 30 (PP4) minutes during pneumoperitoneum, and after (POSTPP) pneumoperitoneum. The respiratory rate was significantly higher at all times compared to PREPP. The end tidal carbon dioxide concentration was significantly higher at PP2, PP3, PP4, and POSTPP, compared to the previous times. The higher values for RR and EtCO₂ were registered at PP4: 22.7 (95% CI 17.6-27.8) breaths/min and 57.9 (95% CI 51.9-63.8) mmHg, respectively. The minute volume was significantly higher at PP4 and POSTPP compared to the other times. The higher value for MV was registered at POSTPP (269.1 (95% CI 206.1-331.8) mL/kg/min). This protocol is suitable for baboons undergoing laparoscopic salpingectomy. The LMA was easy to insert and allowed for good ventilation, gas exchange, and delivery of the anesthetic in spontaneous breathing baboons.

Surgical contraception of free-ranging female capybaras: Description and comparison of open and minimally invasive techniques

OBJECTIVE

To develop, describe, and evaluate 2 surgical techniques for contraception of free-ranging female capybaras.

STUDY DESIGN

Prospective study.

ANIMALS

Cadaveric (n = 3) and free-ranging female capybaras (n = 21).

METHODS

Preliminary studies of surgical anatomy were performed on 3 capybara cadavers. Two different techniques for partial salpingectomy were evaluated in free-ranging female capybaras: bilateral minilaparotomy (LTG; n = 11) or bilateral laparoscopy (LCG; n = 10). Data concerning body weight, tubal ligation time, total surgical time, incision size, and intraoperative and postoperative complications were analyzed, as well as the clinical status and incisional healing 1 week postoperatively.

RESULTS

Body weight (P = .214), ligation time of the left uterine tube (P = .901), and total surgical time (P = .473) were similar between the experimental groups. The ligation time of the right uterine tube was shorter in the LCG group (P = .0463). In the LTG, no differences were observed between the sides regarding the incision size (P = .478). No major intraoperative or postoperative complications occurred in either group. One LCG procedure had to be converted to LTG due to technical issues. All skin incisions healed without complication.

CONCLUSION

Both procedures showed similar and satisfactory outcomes.

CLINICAL SIGNIFICANCE

The proposed techniques may be a suitable alternative to conventional laparotomy for contraception of female capybaras, especially under field conditions.

Laparoscopic salpingectomy in Papio hamadryas for birth control in captivity

OBJECTIVE

To evaluate the feasibility of laparoscopic salpingectomy in baboons (Papio hamadryas). We hypothesized that laparoscopic salpingectomy could be performed in baboon species within a reasonable amount of surgical time, with minor complications occurring at low rates.

STUDY DESIGN

Case series and technique description.

ANIMALS

Sixteen baboons (n = 16).

METHODS

The surgical procedures were performed using the 3-port technique, with 5 mm instruments and a telescope placed at the umbilical and hypogastric regions. A salpinx dissection was performed, using a radiofrequency bipolar vessel sealing device, from the fimbriae to the uterine attachments. We evaluated the surgical duration, learning curve, and intraoperative and early postoperative complications.

RESULTS

Ten adult and 6 subadult baboons with a mean weight of 9.32 kg, a range of 4-14.2 kg, and a standard deviation (SD) of 3.09 kg were included in the study. The total duration of surgery was 28.75 min (range, 16-50 min; SD, 9.60 min). The installation phase was completed in a mean time of 7.68 min (range, 3-15 min; SD, 3.43 min), and the time to complete the salpingectomy of both salpinges was 9.68 min (range, 4-20 min; SD, 3.97 min). No complications were observed in the postoperative period.

CONCLUSION

Laparoscopic salpingectomy in Papio hamadryas was feasible, with an acceptable surgical time, low invasiveness, and only minor technical perioperative complications.

CLINICAL SIGNIFICANCE

Laparoscopic salpingectomy could be a viable and safe therapeutic option in nonhuman primate birth-control programs.

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

Worldwide, primates, and humans increasingly share habitats and often enter in conflict when primates thrive in human-dominated environments, calling for special management measures. Reproductive control is increasingly used to manage population growth but very few monitoring data are available. Therefore, the efficiency and implications of such programs require a careful examination. In the context of a contraception program in wild female long-tailed macaques in Ubud, Bali, conducted over four successive campaigns between 2017 and 2019, including 140 females (i.e., 41.9% of the reproductive females of the population in 2019), modifications of an endoscopic tubectomy procedure, a permanent sterilization method, clinical evaluation of this method, and the post-operative monitoring results of the neutered females after release are described. This surgical approach was applicable for pregnant females: 28.6% of the treated females were pregnant at the time of the surgery. The procedure used a single lateral port to reach and cauterize both oviducts in non-pregnant as well as in early to mid-term pregnant females. Pregnant females nearer to term required a second lateral port to access both oviducts masked by the size of the gravid uterus. Moreover, bipolar thermocauterization was utilized successfully without resection to realize the tubectomy. The average duration of the laparoscopic surgery was 14 min for non-pregnant females and 22 min for pregnant females. Animals were released 3 h 22 min in average following their capture. This short holding time, recommended for free-ranging primates, was made possible by the minimal invasiveness of the sterilization approach. A laparoscopic post-operative evaluation conducted on two patients during the following campaign confirmed that the oviducts were definitely disrupted and no longer patent. Moreover, no new pregnancies in sterilized females were recorded during the 3-year observation period. The survival rate of the treated females 6 months after sterilization was high (96.3%) with no major post-operative complications clinically recorded. Among females that were pregnant during surgery, 81.1% were confirmed to experience term delivery. This study demonstrates the safety and efficiency of endoscopic tubectomy, even for pregnant females, as a mean of wild macaques' population control.

Effect of Infant Presence on Social Networks of Sterilized and Intact Wild Female Balinese Macaques (Macaca fascicularis)

Contraception is increasingly used to control wild animal populations. However, as reproductive condition influences social interactions in primates, the absence of new offspring could influence the females' social integration. We studied two groups of wild macaques (Macaca fascicularis) including females recently sterilized in the Ubud Monkey Forest, Indonesia. We used social network analysis to examine female grooming and proximity networks and investigated the role of infant presence on social centrality and group connectivity, while controlling for the fertility status (sterilized N = 14, intact N = 34). We compared the ego networks of females experiencing different nursing conditions (young infant (YI) vs. old infant (OI) vs. non-nursing (NN) females). YI females were less central in the grooming network than other females while being more central in proximity networks, suggesting they could keep proximity within the group to protect their infant from hazards, while decreasing direct grooming interactions, involving potential risks such as kidnapping. The centrality of sterilized and intact females was similar, except for the proximity network where sterilized females had more partners and a better group connectivity. These results confirm the influence of nursing condition in female macaque social networks and did not show any negative short-term effects of sterilization on social integration.

Open/close-ended vasectomy technique by single incision on vervet monkeys (Chlorocebus pygerythrus)

Vervet monkeys (Chlorocebus pygerythrus), considered a species of "least concern" by the International Union for Conservation of Nature (IUCN), are widely maintained at primate sanctuaries in South Africa. Permanent surgical contraception is a necessary method for the management of this species in captivity. In this study, a new vasectomy technique was evaluated and involves a prescrotal approach with only one surgical incision, aiming to excise a piece of vas deferens, leaving open the testicular side, and creating a loop on the prostatic side to avoid future recanalization. The birth rate was studied to assess the success of the technique. This technique significantly reduced breeding in the study population from 33 births in the first year to four births during the last year of the study. These results show that this type of vasectomy is a fast, simple, and safe technique for controlling monkey populations in sanctuaries.

Endoscopy and Endosurgery in Nonhuman Primates

Endoscopy in nonhuman primates (NHPs) has resulted in improvements in research and clinical care for more than 4 decades. The indications and procedures are the same as in humans and the approach is similar to that in dogs, cats, and humans. Selected procedures are discussed including rhinoscopy, tracheobronchoscopy, upper gastrointestinal endoscopy, laparoscopy, and endoscopic salpingectomy. This short overview provides practitioners with pragmatic elements for safe and effective endoscopy in NHPs.