A Case of endoscopic retrieval of a long bamboo stick from a Humboldt penguin (Spheniscus humboldti)

Abstract

An eighteen-month-old female Humboldt penguin (Spheniscus humboldti) that was 50 cm in length and 4.5 kg in weight was presented with anorexia and vomiting. The hematological and blood biochemical profiles revealed no remarkable findings, and no Salmonella, Shigella or Vibrio spp. were isolated from the fecal culture. However, radiographic imaging revealed a long linear foreign body presenting from the lower esophagus to the stomach. To retrieve this foreign body, flexible endoscopic extraction was performed using flexible rat tooth grasping forceps. A long bamboo stick (29 × 1 cm) was removed from the stomach, and the penguin fully recovered.

The Humboldt penguin (Spheniscus humboldti) inhabits along 4,500 km of the Pacific coast of Peru (6° 30’S) and Chile (39° 52’S) [6], although it is now kept worldwide in aquariums and zoos. Free-ranging and captive marine animals sometimes swallow plastics items, beverage cans, fishing nets and burst balloons, which can result in gastrointestinal disorder [9]. Gastric obstruction by foreign bodies is fairly common in animals. Endoscopy, which does not require laparotomy, has been known to be helpful to retrieval of foreign bodies from the esophagus, stomach and duodenum [1]; therefore, endoscopy is used in animals with such afflictions. Endoscopy may be useful in marine animals, such as penguins, because retrieval of foreign bodies by laparotomy might prevent healing by contact of water in the wounds. Here, we describe that a practical retrieval method using endoscopy apply to a Humboldt penguin ingested a long foreign body.

An eighteen-month-old, female Humboldt penguin (50 cm in length, weighing 4.5 kg) that was kept in an aquarium with other Humboldt penguins was presented with anorexia and vomiting for two weeks. There were no remarkable findings on physical examination; therefore, radiographic imaging, complete blood count (CBC) excluding red blood cell count (IDEXX Reference Laboratories, Westbrook, ME, U.S.A.), blood biochemical profile (Beckman AU Analyzer, Brea, CA, U.S.A.) and fecal culture (IDEXX Reference Laboratories) were conducted. Blood was collected from the medial metatarsal vein, using 21gauge needles. There were no remarkable findings on CBC, while the blood biochemical profile revealed mild elevation (1.5 fold) of aspartate aminotransferase (AST), creatine kinase and amylase and slightly lower levels of total protein and albumin compared to the reference (Table 1) [2, 11]. Moreover, no Salmonella, Shigella or Vibrio spp. were isolated from fecal culture. However, radiographic imaging revealed a long linear foreign body lodged from the lower esophagus to the stomach.

Table 1. Hematological and blood biochemical profiles in a Humboldt penguin (Spheniscus humboldti).

Parameter	Value	Reference
WBC (103 × /ul)	20.5	26.49 ± 11.43
Hematocrit (%)	53	48.9 ± 6.7
Heterophil (103 × /ul)	17.425	14.85 ± 6.824
Heterophil band (103 × /ul)	0
Lymphocyte (103 × /ul)	2.87	9.578 ± 6.293
Monocyte (103 × /ul)	0	0.37 ± 1.282
Eosinophil (103 × /ul)	0	0.644 ± 0.796
Basophil (103 × /ul)	0.205	0.68 ± 0.533
AST (U/l)	321	191 ± 83
Creatine Kinase (U/l)	837	236 ± 219
GGT (U/l)	0	8 ± 5
Amylase (U/l)	2,816	1,359 ± 363
Albumin (g/dl)	1.1	1.7 ± 0.3
Total protein (g/dl)	3.7	5.5 ± 0.7
Globulin (g/dl)	2.6	3.8 ± 0.7
BUN (mg/dl)	4	4 ±1
Cholesterol (mg/dl)	150	110 ± 221
Glucose (mg/dl)	297	245 ± 47
Calcium (mg/dl)	10.1	11.1 ± 2.3
Phosphorus (mg/dl)	1.3	4 ± 2
Chloride (mmol/l)	110	112 ± 5
Potassium (mmol/l)	3.1	3.9 ± 1
Sodium (mmol/l)	150	152 ± 6
Uric Acid (mg/dl)	5.1	7.9 ± 5.3
Triglycerides (mg/dl)	89	110 ± 221
Bile Acids (umol/l)	1.8

Reference value from [2].

A flexible endoscope (EPK-i7000, Pentax, Tokyo, Japan) was utilized to retrieve this foreign body. For endoscopic retrieval, the penguin was anesthetized with 5% isoflurane (Forane sol., Choongwae, Seoul, Korea) in oxygen administered by a face mask. The penguin was then intubated with a 4 mm uninflated cuffed endotracheal tube, and anesthesia was maintained with 2% to 4% isoflurane in oxygen (flow rate, 1 to 1.5 l/min) with spontaneous ventilation [8]. After the penguin was anesthetized, a scope (EG27-i10; diameter 90 mm/ working length 1,050 mm/ working angle 210 degrees, flexible type, Pentax) was inserted into the esophagus. At first, endoscopic extraction was attempted by alligator grasping forceps (alligator-jaw; channel diameter 2.8 mm, working length 230 mm and opening width 7.5 mm, Olympus, Nagano, Japan), but this procedure failed, because the foreign body was heavy and slippery. After the alligator grasping forceps were changed to flexible rat tooth grasping forceps (rat tooth; channel diameter 2.8 mm, working length 230 mm and opening width 20 mm, Olympus), a long bamboo stick (29 × 1 cm) was removed (Fig. 1A). The end of the foreign body was tightly stuck in the gastric antrum mucosa, resulting in inflammation (Fig. 1B). Endoscopy was finished within 25 min. After retrieval of the foreign body, sucralfate (250 mg/kg, SID, PO, 7 days; JW Pharm, Seoul, Korea) was prescribed, and the penguin fully recovered.

Fig. 1.

Endoscopic images of the stomach in the Humboldt penguin (Spheniscus humboldti). (A) The rat tooth forceps grasped the end of the long bamboo stick. (B) After retrieval of the long bamboo stick, inflammation was observed in the stomach.

Foreign bodies should be retrieved as soon as possible after ingestion, especially in the case of long linear foreign bodies, which can cause inflammation and perforation [10]. Removal of ingested foreign bodies is commonly accomplished using medicine or surgery depending on the size, location, type of material, and condition of the patient. Endoscopic removal of foreign bodies is less invasive than laparotomy, but can only be performed in selected cases. Objects with well-defined edges that are not stuck in the mucosa are more likely to be retrievable using grasping forceps. However, the foreign bodies are usually slippery and stuck to the mucosa. Therefore, endoscopic retrieval is difficult and has only been partially successful [7]. For the successful retrieval of foreign bodies that are slippery and stuck to the mucosa, proper equipment, including grasping forceps and snares, should be selected. Moreover, the operator should understand the morphology of the gastrointestinal tract in each species [10]. The retrieval of long objects, such as the bamboo stick, is especially challenging, because they are usually coated with slippery mucus. In this study, we first attempted retrieval with alligator grasping forceps, but this forceps failed to grasp the object coated with slippery mucus. Therefore, to overcome this problem, we utilized rat tooth grasping forceps, which successfully retrieved the object. The reason was that the tip of rat tooth forceps was hocked. Therefore, rat tooth forceps catch the object easier than alligator grasping forceps did [10].

Information regarding clinical hematology and blood biochemical profile can be useful to diagnosis of animals. However, a few studies have revealed the clinical hematology and blood biochemical profile of penguins [4, 5]. In this study, there were no remarkable findings on CBC, but mild elevation of AST, creatine kinase and amylase and slightly lower levels of total protein and albumin were found. The AST, creatine kinase and amylase values are mainly associated with the damage of liver and skeletal muscle, skeletal and cardiac muscle, and the salivary gland and pancreas, respectively [3]. It is presumed that the levels of AST and creatine kinase are elevated during the process of transferring the penguin from the aquarium to the hospital for blood sampling and radiography, while the capture and retention of the penguin occur. The mild elevation of amylase might be due to the spread of inflammation from the stomach to the pancreas. Total protein and albumin can be decreased, because of decreased protein intake [3]. Therefore, we can assume that the slightly decreased level of total protein and albumin was due to anorexia and vomiting. In this study, the hematological and blood biochemical profiles were similar to those previously reported [11]. However, the further studies about clinical hematology and blood biochemical profile of Humboldt penguins should be required.