Introduction
An adult rat snake (Pantherophis alleghaniensis) of unknown sex found in Randolph County, NC, (snake 1) was evaluated at the Valerie H. Schindler Wildlife Rehabilitation Center at the North Carolina Zoo after being found inside a chicken coop with a spherical, golf ball–sized mass in the midbody region. The property owner suspected that the snake had recently eaten a golf ball that was placed in a nesting box. The snake with the ingested ball weighed 0.45 kg (1.0 lb) and was bright and alert, with no abnormalities evident on physical examination other than the described distended area. A dorsoventral radiograph revealed a round structure of homogenous mineral opacity consistent with a golf ball in the midcoelom.
Nonsurgical removal of the foreign body was performed on the day of admission to the facility. Morphine (0.66 mg/kg [0.3 mg/lb], IM) was administered, and the snake was anesthetized with isoflurane in oxygen delivered with positive-pressure ventilation via an uncuffed silicone endotracheal tube. A red rubber catheter was advanced into the aboral region of the esophagus to infuse water-based lubricant around the ball. The ball was externally manipulated by hand to be gradually advanced orad within the esophagus. The ball advanced without difficulty and was expressed out of the oral cavity. The snake recovered from anesthesia uneventfully and was hospitalized; on day 7 of hospitalization, the snake was fed a thawed, previously frozen mouse and passed normal feces and urates. No complications were observed after the procedure or during hospitalization, and the snake was released 14 days after golf ball removal.
An adult male rat snake found in Orange County, NC, (snake 2) was evaluated by the Turtle Rescue Team at the North Carolina State University College of Veterinary Medicine because of a firm, round, golf ball–sized midbody mass. The snake had been observed in this condition for approximately 1 month prior to being caught and presented for care. The snake with the ingested ball weighed 0.955 kg (2.10 lb). The snake had crusted dermal abrasions with scale loss dorsal and ventral to the mass and appeared slightly underconditioned. Radiography revealed a radiopaque golf ball–sized spherical mass in the gastrointestinal tract at the level of the stomach (Figure 1).
Lateral radiographic view of an adult male rat snake (snake 2) that was evaluated because of a firm, spherical, golf ball–sized midbody mass that was estimated to have been present for 1 month before the animal was caught and presented for treatment. The ingested foreign body has a uniform mineral opacity typical of a golf ball.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
Lateral radiographic view of an adult male rat snake (snake 2) that was evaluated because of a firm, spherical, golf ball–sized midbody mass that was estimated to have been present for 1 month before the animal was caught and presented for treatment. The ingested foreign body has a uniform mineral opacity typical of a golf ball.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
Lateral radiographic view of an adult male rat snake (snake 2) that was evaluated because of a firm, spherical, golf ball–sized midbody mass that was estimated to have been present for 1 month before the animal was caught and presented for treatment. The ingested foreign body has a uniform mineral opacity typical of a golf ball.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
The snake was hospitalized for observation and treatment planning and prepared for nonsurgical removal of the ingested ball. On day 4 of hospitalization, anesthesia was induced with propofol (7.5 mg/kg [3.4 mg/lb], by intracardiac injection1). Ketamine (15 mg/kg [6.82 mg/lb], IM) was subsequently administered at the beginning of the procedure for additional sedative effect. The snake was intubated with an uncuffed silicone endotracheal tube, and anesthesia was maintained with isoflurane in oxygen. A 140-cm-long, 8.9-mm-diameter endoscopea lubricated with a water-based gel was passed through the oral cavity to examine the gastrointestinal tract. The golf ball was visible at the level of the stomach, which was identified by the transition to glandular gastric mucosa. The esophageal and gastric mucosa appeared normal. The golf ball was advanced orad in a manner similar to that for snake 1. Sterile saline (0.9% NaCl) solution was injected through the endoscopy port to ease passage of the ball. Endoscopic visualization was maintained throughout the procedure. When the ball was approximately 10 cm away from the oral cavity, increased tension on the skin caused the skin to rupture over the ball, resulting in a 6-cm full-thickness longitudinal tear in the right lateral cervical region. External pressure on the golf ball was discontinued to prevent further expansion of the skin defect, and the endoscope was withdrawn. The snake's heart rate immediately before and at the time the ball became entrapped was 80 and 70 beats/min, respectively. The snake was temporarily extubated, and the endoscope was reinserted for assessment of the esophageal lumen. No intralumenal defects were appreciated, and a Foley catheter was inserted into the esophagus with endoscopic guidance. Extubation reduced the number of medical devices in the oral cavity and allowed the endoscope and Foley catheter to be manipulated more freely; on the basis of the skin tear location, which was caudal to the end of the endotracheal tube, the endotracheal tube was not believed to have contributed to difficulty in moving the golf ball. The balloon tip was inflated, creating a lower-pressure pocket cranial to the golf ball. The golf ball was carefully manipulated orad, with less resistance, into the pocket created by the catheter balloon. This technique was repeated by deflating the catheter balloon, moving it orad, and reinflating it until the golf ball was passed out through the oral cavity. Once the ball was removed, the snake was reintubated. The skin defect was closed with 4-0 poliglecaprone 25 in an interrupted horizontal mattress suture pattern. The endoscope was reinserted down the length of the esophagus to the level of the stomach. Reactive erythema was noted segmentally along the esophageal mucosa (Figure 2). Accumulations of caseous debris were noted at the impaction site, which was also erythemic, but no ulcerations or mucosal tears were observed. The snake's weight after golf ball removal was 0.906 kg (1.99 lb). Postoperative treatment included ceftazidime (20 mg/kg [9.09 mg/lb], IM, q 72 h) for 7 doses with ketoprofen (2 mg/kg [0.91 mg/lb], IM, q 24 h) for 3 doses for analgesia. The snake recovered without additional clinically relevant complications. Within 9 days after the endoscopy procedure, the snake was observed drinking water, and it had defecated and passed urates. On days 13, 15, and 29 after endoscopy, the snake was offered a thawed, previously frozen mouse and ate readily. On day 30 after endoscopy, sutures were removed and the snake was released.
Endoscopic images obtained before (A) and after (B) removal of an impacted golf ball from snake 2. A—The esophagus orad to the golf ball appears normal. B—Immediately after removal of the ball, segmental inflammation characterized by reactive erythema is present with mucosal debris along the esophagus.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
Endoscopic images obtained before (A) and after (B) removal of an impacted golf ball from snake 2. A—The esophagus orad to the golf ball appears normal. B—Immediately after removal of the ball, segmental inflammation characterized by reactive erythema is present with mucosal debris along the esophagus.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
Endoscopic images obtained before (A) and after (B) removal of an impacted golf ball from snake 2. A—The esophagus orad to the golf ball appears normal. B—Immediately after removal of the ball, segmental inflammation characterized by reactive erythema is present with mucosal debris along the esophagus.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
An adult female rat snake found in Carteret County, NC, (snake 3) was evaluated at the North Carolina State University Center for Marine Sciences and Technology after ingestion of a golf ball. This snake was also found on the property of a chicken keeper who noticed the snake had an abnormal midbody swelling. The property owner suspected it had been 1 or 2 days since the ingestion occurred. The snake with the ingested golf ball weighed 0.55 kg (1.21 lb) and was bright and alert; other than the distention, physical examination results were unremarkable. A single dorsoventral radiograph was obtained and showed a spherical object of homogenous mineral density consistent with a golf ball in the midbody region.
For foreign body removal, the snake was administered alfaxalone (5 mg/kg [2.27 mg/lb], IV [in the ventral tail vein]). Moderate to heavy sedation was achieved. During attempted manual removal of the ball as described for snake 1, snake 3 became reactive and was administered an additional dose of alfaxalone (2.72 mg/kg [1.24 mg/lb], IV). A red rubber catheter was used to deposit water-based lubricant in the aboral portion of the esophagus, and the ball was massaged orad as previously described. Once the ball was advanced to approximately 10 cm from the oral cavity, increased tension caused a full-thickness linear rupture of skin on the lateral aspect of the body over the ball. The intact esophagus containing the ball in its lumen protruded through the skin defect, and the decision was made to convert to a surgical removal procedure. Throughout the procedure, including the time of skin rupture, the snake's heart rate ranged from 60 to 80 beats/min.
The snake was intubated with an uncuffed silicone endotracheal tube, and anesthesia was maintained with isoflurane in oxygen and intermittent positive-pressure ventilation. The area around the ruptured skin was aseptically prepared, and a linear incision was made into the esophageal lumen to remove the ball. All visible structures in the region, including the trachea, right lung, and right jugular vein, appeared normal. The esophageal incision was sutured with 5-0 poliglecaprone 25 in a simple continuous pattern. The skin was closed with 4-0 poliglecaprone 25 in an interrupted horizontal mattress suture pattern. The snake recovered uneventfully and was treated with ceftazidime (22 mg/kg [10 mg/lb], IM, q 72 h) for 5 doses and ketoprofen (2 mg/kg, IM, q 72 h) for 3 doses. Ketoprofen was administered less frequently for this patient than for snake 2 so that the treatment coincided with days when ceftazidime was administered and the snake would be handled less frequently. The snake passed feces 7 days after surgery and ate a thawed, previously frozen mouse 9 days after surgery. There were no additional complications, and on day 32 after surgery, the skin sutures were removed and the snake was released.
An adult female rat snake found in Chatham County, NC, (snake 4), was evaluated at the same facility as snake 2 after ingesting an artificial egg. The snake was found on the property of a chicken keeper, who noticed that it had an abnormal midbody swelling and that an artificial egg used to replace the eggs in one of the nest boxes was missing. The interval between ingestion of the artificial egg and presentation of the snake for treatment was unknown. The snake with the ingested foreign body weighed 0.323 kg (0.71 lb). On physical examination, the animal was bright and alert. In multiple areas, there were patches of scale loss, the largest (approx 1 × 0.5 cm) located directly over the mass on the lateral aspect of the snake. There was also diffuse epaxial muscle atrophy. These signs suggested that the ingested foreign body was chronic, causing the animal to go without food and develop pressure sores around the mass. Radiographic examination confirmed an ovoid foreign body in the stomach with a mineral-opacity exterior surrounding a gas-opacity interior consistent with an artificial egg (Figure 3). The foreign body appeared larger relative to the coelomic cavity than the previously described golf balls. The snake was hospitalized and treated with lactated Ringer solution (20 mL/kg, SC, q 24 h) and ketoprofen (2 mg/kg, IM, q 48 h).
Lateral radiographic view of an adult female rat snake (snake 4) that ingested an artificial egg. The ingested foreign body has a gas-opacity interior surrounded by a mineral-opacity shell.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
Lateral radiographic view of an adult female rat snake (snake 4) that ingested an artificial egg. The ingested foreign body has a gas-opacity interior surrounded by a mineral-opacity shell.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
Lateral radiographic view of an adult female rat snake (snake 4) that ingested an artificial egg. The ingested foreign body has a gas-opacity interior surrounded by a mineral-opacity shell.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
Three days after the initial evaluation, the snake was prepared for endoscopy and foreign body removal. Anesthesia was induced with alfaxalone (7.5 mg/kg) and dexmedetomidine (100 μg/kg [45.45 μg/lb]) IV. An additional dose of alfaxalone (5 mg/kg, IV) was given just before endoscopy for complete muscle relaxation. The snake was intubated with a red rubber catheter cut straight across to the appropriate length. The cut tip was briefly flamed to soften and round the sharp edges. Intermittent positive-pressure ventilation was provided with room air. An endoscopea was used to examine the gastrointestinal tract and confirm presence of the artificial egg in the stomach. The esophageal mucosa and visible portions of the gastric mucosa appeared normal prior to the attempt at nonsurgical removal. The artificial egg was advanced orad in a manner similar to that described for snake 1, but subjectively, more resistance was encountered. A lubricated Foley catheter was used to aid advancement of the foreign body as previously described, this time passing the tip and balloon of the catheter aborad to the foreign body. The balloon was inflated with air, and gentle pressure was placed over the inflated balloon to advance it orad. Simultaneously, a second person maintained gentle tension on the catheter near the oral cavity. This method allowed for advancement of the artificial egg while reducing additional tension on the skin directly surrounding it in an effort to prevent skin rupture. Although initially successful, once the foreign body approached the cervical area, the increased tension caused the skin to rupture (Figure 4). Heart rate recorded during esophagoscopy and prior to the attempted foreign body removal was 48 beats/min. Following esophagotomy, the heart rate was 60 beats/min. Heart rates throughout the procedure were within expected limits for stable anesthesia.
Images obtained during and after an unsuccessful attempt at manual removal of the artificial egg in snake 4 (A) and during endoscopic examination of the esophagus after the foreign body was removed via esophagotomy (B). A—Photograph depicting full-thickness skin rupture that resulted from skin tension over the artificial egg. The intact esophagus containing the foreign body is protruding through the primarily linear skin defect. B—Postoperative endoscopic image showing a linear lesion (arrowheads) in the esophageal lumen that resulted from contact with the abrasive surface of the artificial egg.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
Images obtained during and after an unsuccessful attempt at manual removal of the artificial egg in snake 4 (A) and during endoscopic examination of the esophagus after the foreign body was removed via esophagotomy (B). A—Photograph depicting full-thickness skin rupture that resulted from skin tension over the artificial egg. The intact esophagus containing the foreign body is protruding through the primarily linear skin defect. B—Postoperative endoscopic image showing a linear lesion (arrowheads) in the esophageal lumen that resulted from contact with the abrasive surface of the artificial egg.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
Images obtained during and after an unsuccessful attempt at manual removal of the artificial egg in snake 4 (A) and during endoscopic examination of the esophagus after the foreign body was removed via esophagotomy (B). A—Photograph depicting full-thickness skin rupture that resulted from skin tension over the artificial egg. The intact esophagus containing the foreign body is protruding through the primarily linear skin defect. B—Postoperative endoscopic image showing a linear lesion (arrowheads) in the esophageal lumen that resulted from contact with the abrasive surface of the artificial egg.
Citation: Journal of the American Veterinary Medical Association 258, 10; 10.2460/javma.258.10.1135
An esophagotomy (as described for snake 3) was performed to remove the artificial egg, and endoscopy (as described for snake 2) was repeated after foreign body removal. Sections of the esophagus appeared inflamed with linear striations and mucosal ulceration (Figure 4). At the time of endoscopic evaluation, it was suspected that ≥ 1 of the ulcerations could have been a full-thickness lesion through the esophageal wall, but this could not be confirmed during the procedure. Surgical exploration of the esophageal lesions was not pursued because the anesthetic episode had been prolonged owing to the described complications during the procedure, and a clinical decision was made to recover the snake from anesthesia and allow the esophageal lesions to heal by second intention. The snake had a prolonged but otherwise uneventful recovery from anesthesia.
The snake weighed 0.272 kg (0.60 lb) after removal of the foreign body. In the days following surgery, the snake was lethargic and had reduced muscle tone in the caudal half of its body. Subcutaneous fluid therapy and ketoprofen administration were continued, and ceftazidime (20 mg/kg, IM, q 72 h) was added to the treatment regimen. The snake showed mild improvement in activity level and muscle tone but these were still deemed abnormal. Although nutritional support was desired, it was considered best to avoid feeding whole prey items at this time. On day 8 after surgery, 15 mL of a carnivore feeding formulab was given via a feeding tube. The snake had minimal improvement in the following days and was fed an additional 15 mL of the feeding formula on day 15. The next day, the snake was found dead. A gross postmortem examination revealed the presence of food material in the esophagus, oral cavity, and nasal cavity as well as the stomach and proximal portion of the intestine. On histologic examination, foreign material with mixed bacteria and inflammatory cells was found adhered to multiple serosal surfaces including the trachea, lungs, epicardium, and oviduct. Additional findings included advanced muscle atrophy and depleted coelomic fat stores, supporting that the presence of the foreign body had been chronic. Death was due to regurgitation and subsequent aspiration along with coelomitis secondary to the leakage of food through esophageal perforations.
Discussion
Ingestion of inedible foreign bodies by snakes has been previously described.2,3,4,5,6,7 Rat snakes are a common species of nonvenomous colubrid found in North Carolina. Although they typically feed on live prey, rat snakes are opportunistic feeders that consume bird eggs when available, and chicken nest boxes often become their hunting grounds. There is a practice among chicken keepers to place golf balls or artificial eggs in nest boxes as a means of encouraging young layers to use the boxes, as hens are stimulated to incubate these items. These inedible objects also discourage egg eating by other hens in the flock.3 The physical and olfactory properties of golf balls and artificial eggs in nest boxes can lead rat snakes to misidentify and ingest them.3,4,6 Once ingested, the foreign body cannot be broken down or regurgitated, creating an immovable gastrointestinal obstruction that inevitably becomes fatal without intervention.
Golf balls or artificial eggs ingested by snakes have been successfully removed by gastrotomy.3,4,6 Recovery time after gastric foreign body surgery is likely to be ≥ 4 weeks, and if the recovery period extends into the start of winter, patients may need to be held in a rehabilitation facility until the following spring owing to an inability to adequately adjust to winter climates immediately upon release.3,6,7 Snake 1 underwent nonsurgical removal of a golf ball and experienced no complications; the hospitalization time for this patient was 14 days, less than half the time needed for snakes that required skin rupture repair and survived to hospital discharge. In addition to a protracted recovery time, gastrointestinal tract surgery requires surgical expertise and results in increased costs.
In addition to the snakes described in the present report, other snakes that ingested spherical or ovoid foreign bodies have been successfully treated under general anesthesia with nonsurgical methods by one of the authors (RSD). Video recordings of nonsurgical removal of ingested balls from snakes by laypersons and veterinary professionals can also be found on the internet.8,9 Despite anecdotal reports that this approach can result in favorable outcomes with few complications, the cases described in the present report illustrate the unfavorable outcomes that can occur. Each of the described cases included a unique aspect of management or complications that clinicians may encounter when a nonsurgical approach is used. The foreign body was removed retrograde through the oral cavity for snakes 1 and 2, but snake 2 required surgical repair of a skin rupture. A similar complication for snakes 3 and 4 resulted in conversion to esophagotomy, with successful results and ultimately release from the hospital for snake 3; however, for snake 4, the initial nonsurgical approach likely contributed to complications that led to the snake's death.
The surface texture and size of the foreign body relative to the size of the snake appeared to contribute to the outcomes for the snakes of the present report, as the 3 snakes that ingested golf balls survived and the 1 that ingested the artificial egg did not. The golf balls had a smaller diameter than the artificial egg ingested by snake 4. The golf balls were also fairly smooth, whereas the artificial egg was covered in abrasive paint that likely contributed to the resistance encountered in maneuvering it and the subsequent esophageal erosions and perforation.
Snake size may also be another important factor to consider. Snake 4 was the smallest of all the snakes described in this report, with a body weight of only 0.272 kg after the artificial egg was removed. Although snake 1 was the only patient without complications, we considered it possible that the larger sizes of snakes 2 and 3 could have contributed to their better outcome, compared with snake 4.
Chronicity of the condition was also likely to have contributed to the complications seen in some of these snakes. Snake 4 had the most evident signs that the interval between foreign body ingestion and presentation for treatment was excessively long. The snake was dehydrated, had developed visible pressure sores around the foreign body, and had advanced muscle atrophy and depleted coelomic fat stores on necropsy. These chronic issues likely contributed to the snake's incomplete recovery. It was also possible that chronic stretching of the gastrointestinal tract led to atony and adhesions between the mucosa and the foreign body, complicating its removal. Although it could not be determined definitively, snake 1 was suspected to have ingested the golf ball most recently prior to the clinical evaluation, possibly ≤ 24 hours before this time. The short duration of the condition might have contributed to the success of the procedure and lack of complications if the muscles that facilitated swallowing were still stretched and relaxed.
The anatomic features of oophagous snakes may also present challenges to nonsurgical foreign body removal by means of retrograde manipulation. Many oophagous snakes have elongated hypapophyses that extend from the ventral aspect of the vertebrae along the esophagus, where they function to break the eggshell as it passes toward the stomach. Hypapophyses are most advanced in African egg-eating snakes (Dasypeltis spp), in which they extend into loose folds of the esophagus to prevent passage of an intact egg. The egg is crushed, allowing the contents to progress to the stomach, and the shell is regurgitated.10,11 Multiple genera of opportunistic oophagous species, including New World (Pantherophis spp) and Old World (Elaphe spp) rat snakes, kingsnakes (Lampropeltis spp), and gopher snakes (Pituophis spp), also have hypapophyses cranial to the level of the stomach.12,13,14 In the snakes of the present report, it is likely that these structures acted as a physical barrier to the retrograde movement of spherical and ovoid foreign bodies.
A mechanism serving as a functional esophageal sphincter separating the oropharyngeal cavity and cranial portion of the esophagus that has been observed in fluoroscopic swallowing studies has been proposed to exist in multiple species of snakes, including Pantherophis spp. This mechanism to create a functional division in the cranial portion of the alimentary tract is believed to facilitate retention of water in the esophagus during drinking.15,16 Although a definitive anatomic structure or mechanism for functional control has not been described, if a cranial esophageal constriction is present during retrograde foreign body movement, this could have presented another barrier for orad passage or led to increased intraluminal pressure in the caudal portion of the esophagus, possibly causing some of the complications encountered in these snakes.
One possible complication that should be considered prior to an attempt at nonsurgical retrograde foreign body removal is that the object could become entrapped at the level of the heart, and severe cardiovascular compression or collapse could occur. During normal egg swallowing, the vertebral hypapophyses rupture the egg before it reaches the level of the heart in Dasypeltis spp. This also occurs in rat snakes, except that in large snakes an intact egg can pass into the stomach with relative ease, where the shell is partially digested and later passed in the feces.14 Compression of the heart by retrograde movement of a noncompressible foreign body is not an event that snakes, even oophagous species, are structurally adapted to accommodate. There have been unsubstantiated reports of death due to possible cardiac complications in Pantherophis and Pituophis spp attempting to swallow artificial eggs.10 In snakes of the present report that required conversion to esophagostomy for foreign body removal, the foreign body was cranial to the heart before it became entrapped. None of the changes in heart rate in the snakes of this report were perceived to indicate cardiovascular compromise or other clinically important changes. Additionally, necropsy findings for snake 4 did not indicate cardiovascular trauma. However, considering the potential for cardiac complications as well as the possibility of traumatic injury to other tissues, nonsurgical foreign body removal should be performed with caution. Monitoring heart rate throughout the procedure is recommended.
In our experience with these snakes, endoscopy was a useful tool in the 2 cases for which it was available. Endoscopy allowed for visualization of the foreign body and assessment of the gastrointestinal tract prior to undertaking the procedures. The outcome of snake 4 showed that serious complications, including esophageal perforations, may occur secondary to the described nonsurgical techniques. Having endoscopic equipment available to assess the gastrointestinal tract in the event of such complications is highly recommended if these techniques are attempted, especially if the foreign body is suspected to be an artificial egg for which the physical characteristics, such as diameter, mass, and surface texture, are less predictable than those of a standard golf ball. Although a possible full-thickness lesion was suspected in snake 4, the duration of the procedure, additional complications encountered, and status of the patient precluded surgical exploration of the lesions during that anesthetic procedure or during the subsequent recovery period. In snake 2, endoscopic examination revealed trauma to the esophageal mucosa secondary to the procedure that was managed with supportive care and food withholding for approximately 2 weeks. The presence of a normal appetite and absence of further complications suggested that the mucosal injury healed quickly. However, the potential for esophageal injury should be considered in all cases of nonsurgical removal of foreign bodies via the oral cavity in snakes.
Although 3 of the 4 snakes of this report ultimately had the foreign body removed and survived to be released from the wildlife facility, on the basis of the complications encountered with most of these patients, the nonsurgical methods described here cannot be recommended as an alternative to traditional gastrotomy. Our results suggested that veterinarians attempting nonsurgical extraction should proceed cautiously and be prepared to convert to a surgical procedure in the event of complications.
Acknowledgments
The authors thank Dr. Shelly Vaden, Dr. Nanelle Barash, Dr. Rae Hutchins, Patty Secoura, Dr. Maria Serrano, Kent Passingham, Brooks Long, and Dr. Ian Robertson for contributions to case management and manuscript preparation.
Footnotes
Gif Vet PQ140 (VQ-8143), Olympus, Center Valley, Pa.
Carnivore Care, Oxbow, Omaha, Neb.
References
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