Laparoscopic ovariectomy in mares using a polyamide tie-rap

OBJECTIVE: To describe use of a polyamide tie-rap to ligate the mesovarium during standing laparoscopic ovariectomy in mares. STUDY DESIGN: Prospective study. ANIMALS: Ten mares. METHODS: Bilateral ovariectomy was performed in 10 mares. Standing laparoscopic ovariectomy was performed using 3 portals in the paralumbar fossa. A commercial polyamide tie-rap was prepared as a loop and marked with 4 colored lines close to the buckle, to enable us to check whether the loop was tightened securely. The ovary was grasped with forceps and after the mesovarium was minimally transected cranially and caudally, the loop of the tie-rap was inserted in the abdomen and placed around the mesovarium. It was firmly tightened, until at least 3 of the 4 marks were visible, then the end of the tie-rap was cut. The ovary was transected and removed through an enlarged 3rd portal. The contralateral ovary was removed similarly through the opposite paralumbar fossa. Repeat laparoscopy was performed in 8 mares, 2, 3, 4, and 12 weeks later. RESULTS: None of the mares had postoperative discomfort. On repeat laparoscopy, there was complete encapsulation of the stump and tie-rap after 3-4 weeks. In 2 mares, an adhesion between the left stump and the mesentery of the descending colon was observed. CONCLUSION: Ligation of the mesovarium can be easily and safely performed using a polyamide tie-rap during standing laparoscopic ovariectomy in mares. CLINICAL RELEVANCE: Standing laparoscopic ovariectomy using a polyamide tie-rap is a safe, technically easy and reliable surgical procedure in the mare.     

Laparoscopic cryptorchidectomy using electrosurgical instrumentation in standing horses

OBJECTIVE: To describe a technique for laparoscopic cryptorchidectomy in standing horses using electrosurgical instrumentation. STUDY DESIGN: Retrospective clinical study. ANIMALS OR SAMPLE POPULATION: Ten horses, 1 to 7 years of age, with unilaterally or bilaterally retained testes. METHODS: Food was withheld for a minimum of 12 to 24 hours. Horses were sedated using xylazine hydrochloride (0.5 to 1 mg/kg) and butorphanol tartrate (0.02 mg/kg) or detomidine hydrochloride (0.02 to 0.03 mg/kg) and restrained in standing stocks. Three portal sites in the paralumbar fossae were locally desensitized using 2% mepivacaine. After trocar and laparoscope insertion, the ipsilateral testicle, mesorchium, and ductus deferens were identified. The cranial mesorchium was coagulated with either monopolar (one horse) or bipolar (nine horses) electrosurgical forceps, and then the mesorchium, ductus deferens, and ligament of the tail of the epididymis were transected from cranial to caudal using laparoscopic scissors. Once the testis was freed, the transected mesorchium was inspected for hemorrhage and the testis was removed by connecting the two instrument portals (eight horses). In two horses, the testis was placed within a laparoscopic retrieval bag and then removed without enlarging the portal incision. If the testes were retained bilaterally, the retained contralateral testis was removed similarly through the opposite paralumbar fossa. If the contralateral testis was descended, it was removed by a standard, standing castration technique. RESULTS: Vessels of the mesorchium were adequately coagulated using bipolar and monopolar electrosurgical forceps. No immediate or short-term complications occurred in 10 horses at 3 to 11 months after surgery. CONCLUSION: Standing laparoscopic cryptorchidectomy can be performed easily and safely using electrosurgical instrumentation as the sole means of providing hemostasis of the equine mesorchium. CLINICAL RELEVANCE: Standing laparoscopic cryptorchidectomy using electrosurgical instrumentation provides a safe, reliable, and efficient alternative to achieve hemostasis of the equine mesorchium.     

Paralumbar Fossa Laparoscopic Ovariectomy in Horses With Use of Endoloop Ligatures

Objective —The purposes of this study were to develop a technique of paralumbar fossa laparoscopic ovariectomy using Endoloop ligatures and to avoid a laparotomy incision for ovary removal by using a 33–mm diameter muscle spreader trocar-cannula unit.
Animals or Sample Population —Seven mares.
Methods —Bilateral laparoscopic ovariectomy was performed under general anesthesia in two horses and under neuroleptanalgesia and local anesthesia in five standing mares. Ovaries were approached from the ipsilateral paralumbar fossa through two portal sites located in the paralumbar fossa and a third between the 17th and 18th ribs. Insufflation of the abdominal cavity was achieved using an automatic carbon dioxide insufflator. Two Endoloop ligatures were placed on the mesovarium. The cannula, located in the center of the paralumbar fossa, was removed, and a 33-mm diameter trocar-cannula unit, with a cone-shaped muscle spreader extremity, was inserted through the same portal. The mesovarium was transected between the ovary and the ligatures. The ovaries were removed from the abdomen through the 33-mm diameter cannula. The abdominal wall was closed in a routine manner.
Results —No major complications occurred during or after surgery.
Conclusion —Paralumbar fossa laparoscopic ovariectomy in mares using Endoloop ligatures and the 33-mm diameter trocar-cannula unit was an effective technique for ovariectomy of normal ovaries in this study.
Clinical Relevance —Endoloop ligatures provide a viable alternative for laparoscopic ligation of ovarian pedicles in mares.     

Ligature slippage during standing laparoscopic ovariectomy in a mare

Suture ligature failure is a potential complication during laparoscopic ovariectomy techniques utilizing ligatures as a means of hemostasis. This complication in the standing mare and the successful use of laparoscopic electrosurgical instrumentation as the sole means of providing hemostasis to the mesovarium of a mare are described.     

Standing Laparoscopic Ovariectomy Technique with Intraabdominal Dissection for Removal of Large Pathologic Ovaries in Mares

Objective: To describe a standing laparoscopic ovariectomy technique with intraabdominal ovarian dissection inside a specimen retrieval bag for removal of large pathologic ovaries through small incisions. Study Design: Case series. Animals: Mares (n=43) aged 2–21 years and weighing 380–680 kg. Methods: Unilateral laparoscopic ovariectomy was performed on 43 standing sedated mares. Ovaries were approached via 3 portal sites, 2 in the paralumbar fossa and a 3rd between the 17th and 18th ribs on the ipsilateral side. Ovaries were dissected free using either a LiNA Tripol‐bipolar laparoscopic forceps or a Ligasure™ Vessel Sealing Device and removed by enlarging the proximal portal site ventrally using a grid technique. Use of a plastic specimen retrieval bag and cannula suction device facilitated intraabdominal dissection of very large ovaries into 2 or more pieces, before removal through small incisions. Results: Regardless of size, all ovaries were removed successfully through small incisions (range, 5–10 cm), with no major complications and an excellent cosmetic result. All sport horses returned to previous levels of work or higher, with 93% of breeding mares successfully bred in the 1st season after surgery. Conclusions: Large pathologic ovaries can be easily and safely removed by standing laparoscopic ovariectomy on the mare. Clinical Relevance: Standing laparoscopic ovariectomy combined with a small flank incision is a safe and highly effective technique for removal of large pathologic ovaries in the mare, negating the requirement for general anesthesia or large incisions.     

Use of high-power ultrasonic shears for laparoscopic ovariectomy in mares

A method for performing laparoscopic ovariectomy with high-power ultrasonic shears in mares is described, along with results in 10 mares. Briefly, after epidural administration of detomidine and local anesthesia with mepivacaine, 3 cannulas were placed in each paralumbar fossa. A laparoscope was placed through the most dorsal cannula, and a grasping forceps was placed through the most ventral cannula and used to grasp and manipulate the ovary. The ultrasonic shears was then placed through the middle cannula. The jaws of the ultrasonic shears were closed across a portion of the ovarian pedicle, and the instrument was discharged until tissue within the jaws was transected; the process was repeated until the entire ovarian pedicle was transected. Following removal of the right ovary, it was passed to the left side of the abdomen and both ovaries were removed through an incision in the left paralumbar fossa. No major complications were identified in any of the 10 mares. However, excessive bleeding necessitating reapplication of the ultrasonic shears (2 ovaries) or application of ligating clips (8) was encountered with 10 of the 20 ovaries. Laparoscopic ovariectomy with a high-power ultrasonic shears appears to be safe in mares.     

Bilateral laparoscopic ovariectomy in standing mares: 22 cases

OBJECTIVE: To describe a technique for laparoscopic bilateral ovariectomy in standing mares and report the outcome of 22 clinical cases. STUDY DESIGN: Prospective study. ANIMALS OR SAMPLE POPULATION: A total of 22 mares between 4 and 23 years of age, weighing between 360 and 600 kg. METHODS: Mares with normal ovaries, as determined by palpation per rectum, were restrained in standing stocks and sedated with detomidine (0.01 to 0.02 mg/kg intravenously [i.v.]) and butorphanol (0.01 to 0.02 mg/kg i.v.). The laparoscope and instrument insertion sites were infiltrated with 2% lidocaine before incision. One laparoscope portal and two instrument portals were located in each paralumbar fossa. Ovariectomy was accomplished by intracorporeal dissection and ligation of the ovarian pedicles. The two instrument portals in each flank were ultimately connected resulting in a 4 to 5 cm laparotomy to facilitate ovarian removal. RESULTS: No major operative or postoperative complications occurred. Minor complications included incomplete hemostasis of an ovarian pedicle with a single ligature (three mares), transient inappetence, pyrexia and incisional infection. Owner satisfaction and cosmetic results were considered excellent. CONCLUSIONS: Standing laparoscopic ovariectomy appears to eliminate many of the potential complications associated with traditional surgical methods for ovariectomy and avoids the risk of general anesthesia. CLINICAL RELEVANCE: This technique requires minimal laparoscopic instrumentation and will provide surgeons with an alternative approach for bilateral ovariectomy in mares.     

Standing hand-assisted laparoscopic ovariectomy in 65 mares

Objective: To review the efficacy and safety of unilateral ovariectomy by use of a standing hand‐assisted laparoscopic approach and evaluate the effect of ovary size on posttransection hemorrhage after application of a linear stapling device. Study Design: Case series. Animals: Horses (n=65) aged 2–20 years. Methods: Medical records of mares that had ovariectomy performed by use of a standing hand‐assisted laparoscopic approach were reviewed. Data retrieved were signalment, ovary removed (left, right), ovarian size, ovarian pathology, intraoperative and postoperative complications, and length of hospitalization. Results: Mean ovarian diameter was 17 cm. Histopathology (52 mares) confirmed 41 granulosa cell tumors (79%), 8 ovarian cysts (15%), 1 teratoma (2%), and 2 ovaries (4%) without abnormalities. Hemorrhage was observed laparoscopically in 16 mares after transection of the mesovarium. Complications encountered during surgery included 1 mare collapsing in the stocks and 1 mare that hemorrhaged excessively from the incision. Postoperative complications included 2 cases of mild colic. Overall complication rate was 6%. Conclusions: All attempts to remove the target ovary were successful. The approach is safe for the mare, as complications encountered were similar to those recently reported for other approaches.     

Intraoperative pain responses following intraovarian versus mesovarian injection of lidocaine in mares undergoing laparoscopic ovariectomy

OBJECTIVE: To compare intraoperative pain responses following intraovarian versus mesovarian injection of lidocaine in mares undergoing laparoscopic ovariectomy. DESIGN: Randomized controlled trial. ANIMALS: 15 mares between 4 and 20 years old. PROCEDURE: Standard bilateral laparoscopic ovariectomy was performed. Prior to manipulation of the ovary, 2% lidocaine (10 mL) was injected into the ovary and saline (0.9% NaCI) solution (10 mL) was injected into the mesovarium on 1 side, with saline solution (10 mL) injected into the ovary and 2% lidocaine (10 mL) injected into the mesovarium on the other side. Presence (yes vs no) and severity (visual analogue scale) of pain were scored at 5 times (grasping of the ovary, dissection of the mesosalpinx, tightening of the first loop ligature, tightening of the second loop ligature, and transection of the ovarian pedicle) by 2 individuals blinded to treatment and each other's observations. RESULTS: During 4 of the 5 observation periods, significantly fewer mares had signs of pain following mesovarian injection of lidocaine, and during 2 of the 5 observation periods, visual analogue scale score was significantly lower. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that mesovarian injection of lidocaine is associated with significantly lower pain responses, compared with intraovarian injection, in horses undergoing laparoscopic ovariectomy.     

Evaluation of a Motorized Morcellator for Laparoscopic Removal of Granulosa‐Theca Cell Tumors in Standing Mares

Objective: To describe a motorized morcellator technique for laparoscopic removal of granulosa‐theca cell tumors (GCT) in standing mares and to evaluate long‐term outcome. Study Design: Case series. Animals: Mares (n=7) aged 4–15 years, with unilateral GCT. Methods: Tumor size was determined by transrectal palpation and ultrasonography. Standing sedated mares had 3 laparoscopic portal sites in the paralumbar fossa. After laparoscopic observation of the GCT, the mesovarium was desensitized, the ovarian pedicle transected with a LigaSure^® device, and the ovary grasped with forceps and cut in cylindrical tissue blocks using a motorized morcellator. Tissue blocks were removed through the laparoscopic sleeve. Outcome was determined by telephone interview of owners 6–40 months after surgery. Results: Estimated ultrasonographic median GCT diameter was 17 cm (range, 10–22 cm). Surgical time was 2–4.5 hours. There were no surgical complications. Two mares had mild subcutaneous emphysema at the portals after surgery. Convalescence was short, owners were satisfied with cosmetic outcome, and clinical signs associated with GCT did not recur. Conclusion: The motorized morcellator allows piecemeal removal of large GCT through a relatively small laparoscopic portal. Surgical complications were rare and the cosmetic outcome is favorable. Clinical Relevance: A motorized morcellator is a safe and minimally invasive technique for laparoscopic removal of GCT in mares.     

Laparoscopic Anatomy of the Abdomen and Laparoscopic Ligating Loops,Electrocoagulation, and a Novel Modified Electroligation Ovariectomy in Standing Mare

The purpose of this study was to provide a detailed laparoscopic anatomy of the caudal abdominal region of mare in a standing position and to evaluate and modify a technique for standing laparoscopic ovariectomy using combination between hand-tied ligating loop and electrocoagulation techniques, as the ligating loops, electrocoagulation, and modified electroligation laparoscopic ovariectomy were applied using nine adult mares. Laparoscopy was practical and effective for direct visual examination of internal abdominal organs in the mare. Ventral dislocation of abdominal viscera after pneumoperitoneum was established with the mare in standing position, which provided an excellent inspection of the dorsal and ventral structures in the peritoneal cavity on the right and left sides. Standing laparoscopic ovariectomy using an electroligation modified method was considered a safe and effective method for hemostasis of the mesovarium, technically easy, time saving, and economical. The mean surgical time for bilateral ovariectomy was 40 ± 7.63, 60 ± 5.25, and 85 ± 6.43 minutes for electroligation-modified technique, ligating loops technique, and electrocoagulation technique, respectively.     

Evaluation of the harmonic scalpel for laparoscopic bilateral ovariectomy in standing horses

OBJECTIVE: To evaluate use of the Harmonic Scalpel (Ethicon Endo-Surgery Inc., Cincinnati, OH) for performing laparoscopic bilateral ovariectomy in standing horses. STUDY DESIGN: Experimental study. ANIMALS: Eight mares aged 2-20 years and weighing 410-540 kg. METHODS: Standing laparoscopic bilateral ovariectomy was performed in 8 mares with normal reproductive tract anatomy. The Harmonic Scalpel (an ultrasonically activated instrument) was used to simultaneously transect and obtain hemostasis of the ovarian pedicle. Necropsy was performed on 4 mares 3 days after surgery and 4 mares 30 days after surgery. Gross and histopathologic evaluation of the ovarian pedicles was performed to characterize tissue reaction. RESULTS: Complete hemostasis of the ovarian pedicles was obtained in all mares. Median transection time for the ovarian pedicle was 28 minutes. Postoperative complications included transient fever, moderate subcutaneous emphysema, and incisional seroma formation. On necropsy examination, there were no signs of generalized peritonitis, postoperative hemorrhage, or adhesion formation. Mild to moderate acute inflammation and scar formation with moderate chronic inflammation at the ovarian pedicle was found at 3 and 30 days. Median depth of coagulation necrosis at 3 days was 2.87 mm. CONCLUSIONS: The Harmonic Scalpel appears to provide reliable hemostasis of the ovarian pedicle during elective laparoscopic ovariectomy in horses. Clinical Relevance-The Harmonic Scalpel represents a safe alternative to other methods of hemostasis during elective laparoscopic ovariectomy in horses.     

Evaluation of a vessel-sealing device for laparoscopic granulosa cell tumor removal in standing mares

OBJECTIVE: To describe a laparoscopic technique for granulosa cell tumor removal using a vessel sealing device (LigaSuretrade mark) in standing mares. STUDY DESIGN: Retrospective study. ANIMALS: Eight mares (8-24 years old; weighing, 406-525 kg). METHODS: Before surgery, ovarian size and adjacent body wall thickness was determined by ultrasonography. Mares were sedated and after local anesthesia (inverted L and local infiltration), laparoscopic cannulation was performed without insufflation. The mesovarium was anesthetized and the LigaSure instrument applied to the mesovarium for hemostasis and resection to remove the affected ovary. Mares were hospitalized for 24 hours before discharge. RESULTS: Median ovarian diameter was 10.5 cm (range, 6-14 cm). Median surgery time was 75 minutes (range, 40-180 minutes). Hemostasis was achieved using the LigaSure device in all mares. Median length of the abdominal wall incision made to remove the ovary was 13 cm (range, 5-17 cm); no incisional complications occurred. CONCLUSIONS: The LigaSure vessel sealing device provided adequate hemostasis for removal of larger neoplastic ovaries in standing mares. CLINICAL RELEVANCE: Concerns of ligature placement can be alleviated by use of the LigaSure device and standing laparoscopic technique provides excellent observation of the surgical field ensuring hemostasis.     

Evaluation of Single-Incision Laparoscopic Ovariectomy in Standing Mares

Our objective was to compare the invasiveness of single-incision laparoscopic surgery (SILS) and multiport laparoscopic surgery (MLS) for ovariectomy in 5 standing healthy adult Thoroughbred mares. First, laparoscopic ovariectomy was performed by SILS or by MLS on the right paralumbar fossa region in a standing mare. One month after surgery, ovariectomy by the other method was performed on the left side. For surgery evaluation, the surgical time, length of incision, and amount of lidocaine used were recorded and compared between SILS and MLS. Physical examination (body temperature, heart rate, and respiration rate) and hematology (number of leukocytes and hematocrit) were performed before surgery and every day for 7 days after surgery. Similarly, the degrees of swelling, heat, pain, and incisional wound healing were evaluated (grades1-4). The length of incision and amount of local anesthetic for SILS were significantly less than those for MLS. Moreover, the scores for swelling, heat, and pain in the SILS group tended to be lower than those in the MLS group for several days after surgery. We concluded that SILS was less invasive than MLS and is therefore useful for ovariectomy in mares.     

Evaluation of a vessel-sealing device for use in laparoscopic ovariectomy in mares

OBJECTIVE: To evaluate a vessel-sealing instrument (LigaSure) as a method for hemostasis of the ovarian vasculature. STUDY DESIGN: Prospective study. ANIMALS OR SAMPLE POPULATION: Thirteen mares (8 experimental, 5 patients), aged 2 to 20 years and weighing 405 to 500 kg. METHODS: Thirteen mares had standing bilateral laparoscopic ovariectomy using a vessel-sealing device (LigaSure) to provide hemostasis. Eight reproductively normal experimental mares were divided into 2 groups: 1 group was re-examined laparoscopically 72 hours and the other group 10 days after the initial standing laparoscopic ovariectomy. The vessel-sealing device uses high current and low voltage, along with pressure, to reorganize the collagen into a translucent seal to achieve hemostasis of the ovarian vasculature. RESULTS: No major operative or postoperative complications were encountered. Complete hemostasis of the ovarian pedicle was accomplished. One mare had a fever for 24 hours' postoperatively; this responded to a single dose of flunixin meglumine. CONCLUSIONS: The LigaSure appears to be a safe method for hemostasis of the ovarian vasculature. CLINICAL RELEVANCE: Benefits of the LigaSure include no foreign material remaining in the abdomen and minimal to no need for surgical dissection before application. The LigaSure eliminates complications with potential ligature slippage and bleeding during dissection.     

In situ coagulation and transection of the ovarian pedicle: An alternative to laparoscopic ovariectomy in juvenile horses

The feasibility of leaving the ovaries within the peritoneal cavity after laparoscopic coagulation and transection of the ovarian pedicle was assessed in the juvenile horse. Elective ovariectomy was performed on 10 quarter horses, aged 4 to 5 mo, with the fillies in a Trendelenburg position. The mesovarium was isolated, and multiple coagulation and transection cycles were performed until all ovarian attachments had been severed. The ovaries were dropped within the abdomen, and hemostasis of the transected mesovarium was evaluated before closure. The mean surgical time was 33 min (range, 23 to 48 min). Ten weeks after surgery the fillies were humanely euthanized. At postmortem examination, the ovary location within the abdomen was noted. In 1 horse, there was an abdominal adhesion; viscera had been punctured during insufflation. Of the 20 ovaries, 4 were free-floating within the abdominal cavity; the other 16 were enveloped in the free portion of the greater omentum in the cranioventral abdomen. Histologic examination of the ovaries was performed to assess follicle cell viability. In both the free-floating and the attached ovaries, the deep blood vessels and all examined follicular structures were necrotic and partially mineralized. Laparoscopic electrosurgical transection of the ovarian pedicle without removal of the ovaries should be considered an alternative to other ovariectomy techniques that may be performed in young female horses.     

Ovarian, uterine and embryo dynamics in horses versus ponies

Characteristics of the internal genitalia were compared between horses and ponies contemporaneously in a single study by asingle operator. Diameter of the preovulatory follicle for 10 days before ovulation (Day 0) and cross-sectional area of the corpus luteum for 10 days after ovulation were measured in 12 horses and 12 ponies. Follicle growth rate and maximum diameter attained during growth and luteal tissue area were not different between mare types. However, ultrasonic echogenicity of luteal tissue was less on Day 0 (P<0.09) and Day 1 (P<0.01) in ponies than in horses, suggesting that under field conditions mare type should be considered when using the extent of luteal gland echogenicity for estimating the number of days postovulation and luteal function. Circulating concentrations of progesterone averaged over Days 3 to 10 were greater in ponies (10.3 ng/ml) than in horses (8.7 ng/ml) as suggested by a tendency (P<0.1) towards a type-by-day interaction.Luteal, uterine and embryonic characteristics during Days 0 to 40 of pregnancy were compared between 7 horses and 9 ponies. Luteal tissue area of the primary corpus luteum was not different between mare types during Days 0 to 30 and during luteal resurgence after Day 30. The interaction between mare type and day was significant for circulating progesterone concentrations; the interaction seemed to result primarily from higher progesterone levels in ponies during Days 6 to 12 and Days 34 to 40. Progesterone concentrations were about 25% higher in ponies on the approximate days that levels were at their highest in the two types of mares. These results indicate, a need for further studies on the effect of mare size or type on circulating concentrations of progesterone, and the consideration of size or type in clinically evaluating progesterone levels in pregnant mares. Apparent partial recovery of the corpus luteum of the previous estrous cycle occurred during early pregnancy in one pony.Increasing diameter of the embryonic vesicle and the extent of uterine tone were similar between horses and ponies. Although diameter of the uterine horns decreased in parallel for the two mare types during Days 0 to 40, the diameter was significantly less (2.2 mm difference averaged over all days) for ponies than horses. The temporal relationship between an expanding embryonic vesicle concurrently with decreasing uterine horn size and enhanced uterine turgidity is compatible with the postulated mechanism of embryo fixation. The smaller uterus in ponies with no difference in size of the conceptus between mare types could account for earlier fixation of the embryonic vesicle in ponies than in horses.     

Vaccination of pregnant ponies against equine rhinopneumonitis

Bovine herpesvirus 1247 (one dose) was given subcutaneously to five pregnant pony mares between 227 and 319 days of their gestations. There were no adverse clinical reactions, and the virus was not recovered from nasal swabs collected during a 2-week period after vaccination. Four ponies foaled full-term, live, healthy foals. The foal of the fifth mare (No. 1) was found dead, but on the basis of the pathologic and virologic examinations, the virus was not considered to be the cause of the death. At 3 weeks after vaccination, the pregnant pony mares had a 13- to 250-fold increase in serum antibody titer to equine herpesvirus-1. A virulent-virus challenge exposure of all pony mares at 208 days after vaccination resulted in antibody titers greater than those just before this exposure. Virus was recovered from nasal swabs from vaccinated mares only on postexposure day 1, whereas the one control (nonvaccinated) pony shed virus for at least 3 days after challenge exposure. The immunogenic and the nonabortifacient characteristics of the herpesvirus 1247 in pregnant pony mares indicate that it may be useful to vaccinate horses against equine herpesvirus-1.     

Comparison of Intraoperative Behavioral and Hormonal Responses to Noxious Stimuli between Mares Sedated with Caudal Epidural Detomidine Hydrochloride or a Continuous Intravenous Infusion of Detomidine Hydrochloride for Standing Laparoscopic Ovariectomy

Objective: To compare the presence or absence of pain, pain‐related behavioral responses, and hormonal responses to noxious stimuli during standing laparoscopic ovariectomy in mares sedated with continuous intravenous (IV) detomidine infusion and caudal epidural detomidine. Study Design: A double blind prospective study. Animals: Mares (n=12) Methods: Mares were divided into 2 treatment groups; 6 were sedated using continuous IV detomidine infusion and 6 were sedated with caudal epidural detomidine. All mares received IV xylazine (0.33 mg/kg) and butorphanol tartrate (5 mg) premedication before detomidine administration. Venous blood samples were taken to assess serum cortisol levels in each mare at 4 time points: a baseline cortisol measurement after the mares' arrival to the clinic, 10 minutes before surgery, at the removal of the 2nd ovary, and 10 minutes postsurgery. Two surgeons performed bilateral ovariectomy and at 8 time points involving surgical manipulations, noted the presence or absence of pain (yes/no) and scored the patient's response on a 10 cm visual analogue scale (VAS) for pain assessment with 0 indicating no pain responses and 10 cm indicating pain so severe that the mare required additional sedation or analgesia to complete the procedure. Each mare was also assigned a VAS score by each surgeon for the overall satisfaction of analgesia during the entire procedure. Results: Serum cortisol levels between the 2 detomidine administration groups differed significantly at the baseline (precortisol) measurement but not at the 3 remaining time points. Seven of the procedures within the surgeries did not differ significantly in VAS scores between the 2 groups. The initial grasp of the left ovary (the 1st ovary) in the continuous infusion group had a significantly higher (P=.05) median VAS score compared with the caudal epidural group. Conclusions: Mares sedated with a continuous IV infusion of detomidine have similar hormonal and behavioral responses to painful stimuli during standing laparoscopic ovariectomy as mares sedated with caudal epidural detomidine. Clinical Relevance: Sedation using a continuous IV infusion of detomidine can be used for laparoscopic ovariectomy in mares.     

Equine nonneoplastic abnormal ovary in a draft mare with high serum anti-Müllerian hormone: a case study

We performed a standing hand-assisted laparoscopic ovariectomy in a draft mare that presented with high serum anti-Müllerian hormone (AMH) level and had an enlarged single cystic ovary. Histopathological examination revealed no tumor cell proliferation in the ovary, but the presence of a large ovarian cyst was confirmed. In the diagnosis of abnormal ovaries in mares, a comprehensive assessment should be performed, including the monitoring of ovarian morphology and biomarkers over time, to determine the disease prognosis and treatment plan. The case of this mare with a nonneoplastic abnormal ovary and increased serum AMH level was rare. We suggest that standing hand-assisted laparoscopic ovariectomy is useful for the removal of large ovaries in draft mares.