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Ultrasonographic evaluation of abdominal distension in 52 camels (Camelus dromedarius)
Research in Veterinary Science 93 (2012) 448–456
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Ultrasonographic evaluation of abdominal distension in 52 camels (Camelus dromedarius) Mohamed Tharwat a,1, Fahd Al-Sobayil a, Ahmed Ali a, Sébastien Buczinski b,⇑ a b
Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, Qassim University, Saudi Arabia Bovine Ambulatory Clinic, Departement des Sciences Cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Canada
a r t i c l e
i n f o
Article history: Received 28 April 2011 Accepted 12 July 2011
Keywords: Camel Intestinal obstruction Ruptured bladder Trypanosomiasis Ultrasonography
a b s t r a c t The purpose of this study was to assess the diagnostic value of ultrasonography in the evaluation of abdominal distension in 52 camels (Camelus dromedarius). The conditions included trypanosomiasis (n = 35), intestinal obstruction (n = 12) and ruptured urinary bladder (n = 5). Fifteen clinically normal camels were included as controls. Transabdominal and transrectal ultrasonography was carried out on all camels. In animals with trypanosomiasis, ultrasonographic findings included accumulation of massive amounts of hypoechoic abdominal fluids where liver, intestine, kidney, spleen and urinary bladder were imaged floating. Except in two cases of bile duct calcification and one of hepatic abscessation, no detectable abnormal sonographic lesions were detected while imaging the hepatic and renal parenchyma, and the heart and its valves and major blood vessels. In camels with intestinal obstruction, ultrasonographic findings included distended intestinal loops with markedly reduced or absent motility. In one camel, the intestinal lumen contained localised hyperechoic material that was consistent with a foreign body. Hypoechoic fluid with or without fibrin was seen between intestinal loops. In camels with ruptured urinary bladder, ultrasonographic findings included collapsed and perforated bladder, echogenic blood clots within the urinary bladder and peritoneal cavity, increased thickness of the bladder wall, floating intestines in hypoechogenic fluid and echogenic calculi within the urethra. Ultrasonography was considered a useful tool for the evaluation of dromedary camels with abdominal distension. Ó 2011 Elsevier Ltd. All rights reserved.
1. Introduction In camels, abdominal distention is a common clinical presentation (Köhler-Rollefson et al., 2001; Fowler, 2010). There are many conditions in which abdominal distension has been reported. These conditions include trypanosomiasis, cardiomyopathy, hypoprotenaemia, hepatic and renal diseases, septic peritonitis and diffuse malignant neoplasia (Köhler-Rollefson et al., 2001). Other causes of abdominal distention include uroperitoneum due to ruptured bladder, intestinal obstruction, ruminal tympany, foreign bodies, vagus indigestion and advanced pregnancy (Fowler, 2010). Ultrasound has been widely used lately in veterinary medicine. Ultrasound imaging has the advantage over radiology of offering better contrast resolution and acquiring slice images of organs in different planes in real time—all with portable and noninvasive
⇑ Corresponding author. E-mail address: [email protected] (S. Buczinski). Permanent address: Department of Animal Medicine, Faculty of Veterinary Medicine, Zagazig University, Egypt. 1
0034-5288/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.rvsc.2011.07.009
and nonionising equipment (Blond and Buczinski, 2009). During the past 15 years, the use of ultrasonography has become widespread in veterinary medicine through its ease of application in virtually every facet of veterinary medicine and for almost all species (King, 2006). The procedure is a reliable tool to detect various types of disease in different farm animal species (Braun, 2005; Mohamed and Oikawa, 2007; Mohamed, 2010; Mohamed and Oikawa, 2011). In camel practice, the application of ultrasonography is still limited. It is mostly used for reproductive examination and for pregnancy diagnosis (Skidmore et al., 2009; Wani and Skidmore, 2010; Skidmore and Billah, 2011). In the field of internal medicine, however, sonographic studies have not been reported in camels with either abdominal or thoracic disorders. Ultrasonography is of particular interest as an ancillary tool for the diagnosis of common causes of colic and abdominal distension in cattle and horses (Radostits et al., 2007; Braun, 2005; Taylor et al., 2010). In our clinic, abdominal distension in camels is a common reason for referral. The present study was designed to investigate the ultrasonographic findings in camels with abdominal distension as a main clinical sign. To the best of the authors’ knowledge, this is the first study that uses ultrasound to evaluate abdominal distension in dromedary camels.
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vitamin B1, vitamin B12 and copper containing agent (Fercobsang, Vetoquinol, LURE Cedex, France, 20 ml IM). Camels with partial intestinal obstruction due to ruminal foreign bodies were scheduled for rumenotomy.
2. Materials and methods 2.1. Animals, history and physical examination Fifty-two camels (Camelus dromedarius), aged from 6 months to 12 years, were examined in the present study. Cases were primarily referred to determine the cause of abdominal distension, and these animals had also inappetance, loss of body condition, ventral or presternal oedema, urine retention and vomition. Duration of illness ranged from 2 days to 5 weeks. The passive hemagglutination test showed that 35 camels (70%) were positive for Trypanosoma evansi. Thirty-two of the positive camels (91%) were females, nine (28%) lactating. The remaining camels included cases of intestinal obstruction (n = 12) and ruptured urinary bladder (n = 5). Fifteen apparently healthy camels (age: 2.5 ± 1.1 year) were enrolled in this study as controls. Animals were examined at the Veterinary Teaching Hospital, Qassim University, Saudi Arabia, between 2007 and 2011. Clinical examinations of camels were carried out as previously described (Köhler-Rollefson et al., 2001). This included general behavior and condition, auscultation of the heart, lungs, rumen and intestine, measurement of heart rate, respiratory rate and rectal temperature, swinging auscultation, percussion auscultation of both sides of the abdomen and rectal examination.
2.3. Haematological and biochemical analyses Two blood samples were collected from each camel: one placed in a plain tube, and the other in an EDTA tube. Direct smear, buffy coat and haematological examinations (haematocrit, haemoglobin and total and differential leukocyte count) were carried out on the EDTA, the later with the use of an automated veterinary haematological analyser (Vet Scan HM5, ABAXIS, Hungary). Samples in plain tubes were centrifuged at 1200g for 10 min, and serum samples were harvested and stored at 20 °C for future analysis. Commercial kits were used to determine the concentrations of total protein, albumin, glucose, blood urea nitrogen (BUN) and creatinine. The activities of aspartate aminotransferase (AST) and c-glutamyl transpeptidase were measured in serum samples using an automated biochemical analyser (Biosystems A15, Spain). Globulin concentration was obtained by calculating the difference between total protein and albumin. 2.4. Serological detection of T. evansi
2.2. Treatment and follow-up After the initial examination, camels with trypanosomiasis were injected subcutaneously with two doses of a trypanosomicide, AlquinÒ-1.5 (Quinapyramine sulphate, Vetnex, Riyadh, Saudi Arabia, 5 mg/kg BW) two weeks apart, and intramuscularly (IM) with five successive daily doses of an antioedematous – antiinflammatory agent, DiurizoneÒ, (hydrochlorothiazide and dexamethasone, Vetoquinol, LURE Cedex, France, 12 ml IM). Animals were also injected with five successive daily doses of iron, cobalt,
Serum samples were also tested for T. evansi antibodies by passive haemaggluination test as previously described (Omer et al.,
Table 1 History and clinical findings in 52 camels with abdominal distension. Clinical findings
*
Number (%) of camels manifesting clinical signs
Trypanosomiasis (n = 35) Weight loss Abdominal distension Ventral and subcutaneous presternal oedema Weak and irregular gastric contractions Inappetance Fever Recumbency Diarrhoea Decreased milk production
13 (37) 35 (100) 25 (71) 31 (89) 33 (94) 1(3) 5 (14) 9 (26) 9 (100)*
Intestinal obstruction (n = 12) Sunken eyes Vomition Inappetance Ruminal stasis Abdominal distension
11 10 12 12 12
Ruptured urinary bladder (n = 5) Sunken eyes Colicky pain Anorexia Ruminal stasis Abdominal distension Abdominocentesis (red urine) Head oedema Anuria Dribbling
3 3 5 3 5 2 2 2 3
(92) (83) (100) (100) (100)
(60) (60) (100) (60) (100) (40) (40) (40) (60)
All the nine lactating camels examined in this study had a decreased milk production.
Fig. 1. Clinical manifestation in 2 camels with chronic trypanosomiasis. Image (a) shows severe abdominal distension and image (b) shows presternal oedema (asterisks).
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1998). Briefly serum samples were diluted in Tris buffer solution, pH 8.0. Each serum sample was tested using the microtitre technique. Two-fold dilutions of sera from 1:8 to 1: 14,096 were made in V-bottomed microtitre plates (Greiner – Germany). After dilution the T. evansi/red blood suspension was added and incubated at room temperature for 3 h. Sera from uninfected and infected camels were used as negative and positive controls, respectively. Samples showing agglutination at 1:16 were considered positive for T. evansi infection (Ali et al., 2011). 2.5. Ultrasonographic examination
Fig. 2. Vomition in a camel with intestinal obstruction.
Ultrasonographic examination of control and sick camels was carried out in sternal recumbency using 3.5 and 5.0 MHz transducers (SSD-500, Aloka, Tokyo, Japan). The procedure was carried out
Fig. 3. Findings of rumenotomy in camels with partial intestinal obstruction. Together with hair balls (a, b, asterisks), plastic bags and ropes (b, c, white and black arrows) and wires, glass, and other metal objects (d) were discovered.
Table 2 Haematological and biochemical findings (mean ± SD) in 52 camels with abdominal distention compared to controls. Parameters Haematocrit (%) Haemoglobin (g/dL) Leukocyte count (/lL) Neutrophils (/lL) Lymphocytes (/lL) Total protein (g/dL) Albumin (g/dL) Globulin (g/dL) AST (U/L) GGT (U/L) BUN (mg/dL) Creatinine (mg/dL) Glucose (mg/dL)
Trypanosomiasis (n = 35) *
20 ± 4 10 ± 4 15,400 ± 5241** 9086 ± 6251 4928 ± 2589 5.2 ± 2.2* 2.0 ± 1.4** 3.2 ± 0.6 136 ± 88* 52 ± 9 35 ± 11 1.6 ± 0.4 110 ± 40
Intestinal obstruction (n = 12) 24 ± 10 16 ± 5 19,725 ± 1431*** 12,624 ± 8876** 5129 ± 6115 7.2 ± 2.5 3.4 ± 0.9 3.8 ± 0.9 304 ± 154** 32 ± 15 112 ± 72** 1.5 ± 0.5 157 ± 36*
AST = aspartate aminotransferase; GGT = c-glutamyl transferase; BUN = blood urea nitrogen. P < 0.05. * P < 0.01. * P < 0.001 *
Uroperitoneum (n = 5) *
45 ± 11 18 ± 6* 38,289 ± 16,528*** 34,843 ± 17,592*** 2680 ± 3064 7.5 ± 1.2 3.2 ± 1.5 4.3 ± 1.1 88 ± 27 52 ± 13 195 ± 86*** 3.5 ± 2.7** 168 ± 29*
Controls (n = 15) 32 ± 1.4 12 ± 3 8250 ± 2284 7900 ± 1800 3800 ± 1800 7.9 ± 0.4 4.2 ± 0.4 3.7 ± 0.5 69 ± 44 44 ± 22 17 ± 10 1.3 ± 0.2 61 ± 19
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Fig. 4. Flowchart summarising the key ultrasonographic findings that allow the differentiation of the three examined conditions.
Table 3 Ultrasonographic findings in 52 camels with abdominal distention. Ultrasonographic findings
Number (%) of camels
Trypanosomiasis (n = 35) Ascites Oval to round caudal vena cava Distended portal and hepatic veins Bile duct calcification Hepatic abscessation Hydropericardium Hydrothorax Splenomegaly Hepatomegaly
34 (97) 7 (20) 6 (17) 2 (6) 1 (3) 7 (20) 7 (20) 7 (20) 7 (20)
Intestinal obstruction (n = 12) Distended intestinal loops Reduced or absent intestinal motility Intestinal foreign bodies Hypoechoic fluid with fibrin between intestinal loops Hypoechoic fluid without fibrin between intestinal loops
12 (100) 12 (100) 1 (8) 6 (50) 4 (33)
Ruptured urinary bladder (n = 5) Echogenic blood clots within the urinary bladder and peritoneal cavity Increased thickness of bladder wall Uroperitoneum Urethral calculation Perforated bladder wall
Fig. 5. Abdominal ultrasonogram in a camel with trypanosomiasis. Image was taken from the 10th right intercostal space using a 3.5 MHz sector transducer. The liver appears hyperechogenic on ultrasonograms and is floating in a hypoechoic fluid. 1 = hepatic parenchyma; 2 = lung shadow; 3 = anechoic abdominal fluid; 4 = small intestine; DS = dorsal; VT = ventral.
2 (40) 2 5 2 1
(40) (100) (40) (20)
twice, one before, and three weeks after, treatment. Animals were sedated using xylazine 2% (0.3 mg/kg BW IV, Alcomed, Holland). Hair was clipped and shaved on both sides of the abdomen and thorax from the dorsal midline to linea alba. Camels were examined percutaneously and transrectally. After the application of transmission gel to the transducer, the camel was examined starting from the caudal abdomen and extending forward to the third intercostal space on both sides of the thorax. The abdominal viscera including the abdomen, peritoneum, stomachs, spleen, small and large intestines, liver, pancreas and kidneys were imaged. In the thoracic cavity, the lungs, heart and its major blood vessels and the mediastinal region were scanned. Due to a poor prognosis, camels with complete intestinal obstruction and/or ruptured urinary bladder were euthanized and necropsied. 2.6. Statistical analysis Data were presented as means ± SD and the analysis was conducted using SPSS, 2007 program, version 16.0. Haematological
Fig. 6. Hepatic ultrasonogram in a camel with trypanosomiasis. Images were taken from the right 11th intercostal space. Calcification of the bile ducts (white arrow) and hepatic abscessation (black arrow) was detected. PV = portal vein; AS = acoustic shadowing; AE = acoustic enhancement; AB = abscess.
and biochemical data of diseased and control camels were compared, using repeated measures of ANOVA. The level of significance was set at P < 0.05. 3. Results 3.1. Clinical presentations Of the 52 camels with distended abdomen, 35 (67%) had trypanosomiasis, 12 (23%) had intestinal obstruction and five (10%) had a ruptured urinary bladder. The history and clinical findings of the 52 camels with abdominal distention are summarised in Table 1. The most prominent clinical presentations seen in camels
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Fig. 7. Ultrasonographic findings in camels with intestinal obstruction. Ultrasonographic findings included distended intestinal loops with markedly reduced or absent motility (A, B, C). Image D shows a hypoechoic fluid with fibrin (white arrow) between intestinal loops; black arrow points to the intestinal wall. In one camel with partial obstruction, the intestinal lumen contained localised hyperechoic material consistent with foreign body (E). Corrugated ruminal wall was scanned in one camel with intestinal obstruction (F). IL = intestinal loops; FB = foreign body; F = fluid; DS = dorsal; VT = ventral.
with trypanosomiasis were inappetance, weak and irregular ruminal contractions, weight loss, abdominal distension and ventral and subcutaneous presternal oedema (Fig. 1). On clinical examination, ascites was detected by a fluid thrill on ballottement, by fluid sounds on succussion, or by the demonstration of excess fluid in the peritoneal cavity by abdominocentesis. On admission, examination of blood smears from the affected camels showed that the
parasites were detected in only one camel (3%). Twenty days after treatment, abdominal distension and ventral and presternal oedema disappeared in 23 (66%) cases. A telephone-based follow-up recorded that all operated animals made a full recovery. Unfortunately, we could not contact the owners of the other 12 (33%). Partial and complete intestinal obstructions were observed in five and seven camels, respectively. When presented, all cases
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Fig. 8. Ultrasonographic images in 2 camels with ruptured urinary bladder. Image A shows blood clot (BC) within the urinary bladder and image B shows blood clot (BC) within the abdomen. Note the thickened bladder wall (1). UB = urinary bladder; UP = uroperitoneum.
were depressed with reduced gastrointestinal motility. The abdomen was distended bilaterally in all affected camels. The eyes were sunken and the animals were recumbent, with vomition in ten (Fig. 2). If stimulated to stand, camels would struggle and wander in an ataxic manner. In camels with partial obstruction, rectal examination revealed the presence of very hard, spiny faecal particles and distended viscera. In animals with complete obstruction, rectal findings showed a small amount of black faeces stained with mucus or no faeces at all. One camel with complete obstruction died 24 h after admission. In animals with partial intestinal obstruction, the owners reported that their animals had been chewing foreign bodies, especially plastic bags and ropes. In these cases, rectal examination revealed the presence of small amounts of hard feces and distended rumen. Rumenotomy performed in these cases showed presence of plastic bags, ropes, glass, hairballs, wires and nails (Fig. 3). In the five camels with ruptured urinary bladder, attacks of colic and abdominal distention were recorded. One animal with severe colic has died shortly after admission to the hospital. Rectal examination revealed a collapsed bladder and abdominocentesis revealed the presence of urine. Bloody urine was collected from the abdomen of two camels and in each case the head was oedematous. 3.2. Haematological and biochemical findings Compared to control animals, those with trypanosomiasis showed reduced packed cell-volume, neutrophilic leukocytosis, a reduction in haemoglobin concentration and presence of a macrocytic hypochromic anaemia, hypoproteinaemia and hypoalbuminaemia. In camels with intestinal obstruction, laboratory data included neutrophilic leukocytosis, elevated AST activity and hyperglycaemia. In animals with a ruptured bladder, neutrophilic leukocytosis, hyperproteinaemia, hyperglycaemia and elevated concentrations of BUN and creatinine were observed. Compared with the controls, other measured serum values did not differ significantly (Table 2).
3.3. Ultrasonographic findings Fig. 4 summarises ultrasonographic findings in camels with trypanosomiasis, intestinal obstruction and ruptured urinary bladder. Ultrasonographic findings in the 52 camels with abdominal distention are summarised in Table 3. In camels with trypanosomiasis, ultrasonographic findings included accumulation of massive amounts of abdominal fluid, where liver and intestines were imaged floating in a hypoechoic fluid (Fig. 5). Transrectal examination also revealed the presence of excessive amounts of anechoic fluid where the urinary bladder and other pelvic organs were also floating. Other ultrasonographic findings included oval to round caudal venae cavae, distended hepatic and portal veins, bile duct calcification and hepatic abscessation (Fig. 6), which was confirmed at necropsy. Ultrasonographic examination of the thorax revealed the presence of anechoic fluid. Compared to the controls, the liver was imaged beyond the 12th rib and at the right ventrum indicating organ enlargement. Except for two cases of bile duct calcification and one of hepatic abscessation, there were no detectable abnormal sonographic findings detected while imaging the hepatic and renal parenchyma and heart, and its valves and major blood vessels. Three weeks after treatment, twenty-three camels (66%), showed no fluids imaged in the peritoneum, pericardium or pleura. The caudal venae cavae, hepatic and portal veins appeared normal. Compared to the control animals (2.62 ± 0.47 cm), those with intestinal obstruction had ultrasonographic findings which included distended small intestinal loops (5.9 ± 1.8 cm) with markedly reduced or absent motility. In one camel with partial obstruction, the intestinal lumen contained localized hyperechoic material consistent with a foreign body. Hypoechoic fluid with or without fibrin was seen between intestinal loops (Fig. 7). In two camels with a ruptured bladder, ultrasonographic findings included presence of echogenic blood clots within the urinary bladder and peritoneal cavity, with increased thickness of the bladder wall (Fig. 8) that was confirmed at necropsy. Floating intestines in a hyperechogenic fluid were imaged in two camels. In the
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Fig. 9. Ultrasonographic images in a six-month old camel-calf with ruptured urinary bladder. Image A shows urinary calculi within the urethra (white arrow) with acoustic shadowing (arrowhead). Image B shows perforated urinary bladder (white arrow) and image C show floating intestines in uroperitoneum. UB = urinary bladder; DS = dorsal; VT = ventral.
remaining case, floating intestines in a hypoechogenic fluid, echogenic calculi within the urethra and a perforated bladder were imaged clearly in a 6-month-old male camel calf (Fig. 9). 3.4. Postmortem findings Table 4 summarises the postmortem findings in 24 camels with abdominal distension. In camels with trypanosomiasis, 23 animals (66%) recovered after treatment, but 12 (34%) did not, their conditions deteriorated and they were killed and necropsied. Necropsy findings included emaciation, subcutaneous oedema, ascites, hepatomegaly, splenomegaly, hydrothorax and hydropericardium. In
camels with complete intestinal obstruction, necropsy findings included presence of constricted intestines around enteroliths, paralytic ileus and mesenteric torsion (Fig. 10). In camels with ruptured bladder, necropsy findings included uroperitoneum, abdominal haemorrhages and perforated bladders (Fig. 11). 4. Discussion In camels, trypanosomiasis is usually chronic but can be acute with a 90% mortality rate if not treated (Luckins, 1992). Clinical signs and lesions caused by T. evansi in camels are unreliable for a definitive diagnosis (Olaho-Mukani and Mahamat, 2000). In the
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Table 4 Postmortem findings in 24 camels with abdominal distention. Postmortem findings Trypanosomiasis (n = 12) Emaciation Subcutaneous edema Ascites Hydrothorax Hydropericardium Hepatomegaly Splenomegaly Complete Intestinal obstruction (n = 7) Mesenteric constricted intestines around enteroliths Paralytic ileus Mesenteric torsion Ruptured urinary bladder (n = 5) Uroperitoneum Perforated bladder Abdominal haemorrhages
Number (%) of camels showing lesions 10 (83) 9 (75) 12 (100) 7 (58) 7 (58) 7 (58) 7 (58) 3 (43) 3 (43) 1 (14) 5 (100) 5 (100) 2 (40)
Fig. 11. Postmortem findings in a six-month old camel-calf with ruptured bladder. Image A shows uroperitoneum and image B shows perforated urinary bladder wall (black arrow).
Fig. 10. Postmortem findings in a camel with intestinal obstruction. Mesenteric torsion was the most outstanding finding.
present study, trypanosomiasis was suspected clinically in camels showing a chronic weight loss, subcutaneous oedema and ascites. These clinical findings were in agreement with those of other reports (Wernery and Kaaden, 2002). Clinical manifestations including chronic weight loss, subcutaneous oedema and ascites may be associated with trypanosomiasis but not necessarily indicative of the disease in camels (Fowler, 2010). In cases with suspected ascites, a full clinical examination, including a rectal examination and abdominal percussion/ballottement, help to rule out a number of other causes of abdominal distension. The detection by rectal examination of viscera floating in a fluid medium, and a fluid wave on abdominal ballottement suggests the presence of ascites (Radostits et al., 2007). Finding the parasite in the peripheral blood of infected camels may be highly problematic because of low numbers of the organisms and fluctuating parasitaemia. The development of a suitable serological ELISA test resulted in effectively decreasing the economic losses associated with trypanosomiasis; other DNA technologies are being used in endemic countries (Fowler, 2010). In this study, definitive diagnosis was made on the basis of detecting trypanosomes in a blood smear or antibodies in serum. In camels with trypanosomiasis, ultrasonography of the abdomen confirmed the presence of free abdominal fluid. Non-inflamma-
tory ascites due to other disorders, such as right-sided cardiac insufficiency, hepatic and renal disorders, could be ruled out based on the results of the clinical and ultrasonographic findings. The differential diagnosis also included chronic parasitism. Intestinal obstruction is relatively rare in camels (Köhler-Rollefson et al., 2001; Fowler, 2010). Massive intestinal parasite infestation, plastic foreign bodies and enlarged mesenteric lymph nodes may all cause intestinal obstruction (Ramadan et al., 2008). Camels suffering from pica usually eat hair, leading to the formation of phytobezoars and trichobezoars that may reach the intestine causing obstruction (Tanwar, 1985). Other causes of intestinal obstruction include impaction of the spiral colon, dilatation and torsion of the caecum and strangulation of the intestine in inguinal hernia (Köhler-Rollefson et al., 2001). Ultrasonographic findings, such as changes in luminal diameter, motility and intestinal wall thickness, have been used to diagnose intestinal problems in other ruminant species (Braun et al., 1995). In this study, the most important ultrasonographic finding in camels with either partial or complete intestinal obstruction was dilation of the small intestine with a marked reduction or absence of intestinal motility. Fluid was seen between loops of intestine. Accumulation of ingesta in the omasum/abomasum chamber was detected, some of which also had accumulation of ingesta in the rumen. When taken together, these findings were indicative of ileus (Braun, 2005). Similar ultrasonographic findings were reported in cows with ileus attributable to other causes (Braun et al., 1995), and rarely was the cause determined. In this study, we could determine the cause
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of ileus and make a definitive diagnosis of intestinal obstruction in only one of the seven camels (14%). We could also see the foreign body in the intestine in one of the four operated animals (25%). Failure to make an accurate diagnosis may be attributed to the large abdominal circumference in examined camels. Because the depth of penetration of the ultrasound waves 20 cm, only a small part of the intestinal tract is accessible to ultrasonography. The cause of mechanical obstruction is usually beyond the depth of penetration of the ultrasound transducer. Thus, the veterinarian must decide whether exploratory laparotomy is indicated on the basis of the results of the clinical examination, haematological and biochemical analyses and ultrasonography, as well as the value of the camel. Urolithiasis is common as a subclinical disorder among ruminants raised in management systems where the ration is composed primarily of grain, or where animals graze certain types of pasture. In these situations, 40–60% of the animals may form calculi in their urinary tract (Radostits et al., 2007). Rupture of the urinary bladder and subsequent uroperitoneum is a common problem in cattle, and in males, urolithiasis is the underlying cause in the majority of cases (Divers et al., 1982; Bertone and Smith, 1984). Uroperitoneum may be caused by trauma when the bladder is distended or from rupture of the bladder following urethral obstruction. Urine in the abdomen may not arise only from a single or multiple tears in the bladder wall, but also from seepage through the thinly stretched bladder wall in an over-distended bladder (Fowler, 2010). A ruptured urethra has been reported in camels (Gahlot, 1992; Roussel and Ward, 1985). After the bladder ruptures, uroperitoneum results in a series of abnormalities that arise from failure of the excretory process combined with solute and fluid redistribution between the peritoneal fluid and extracellular fluid. Osmotic pressure from hypertonic urine promotes the movement of extracellular water into the peritoneal cavity resulting in clinical dehydration (Radostits et al., 2007). Bladder rupture then leads to gradual development of ascites from uroperitoneum, ruminal stasis, constipation and depression. Finally, uraemia may take 1– 2 weeks to develop to the point where euthanasia is necessary (Roussel and Ward, 1985). Calculus was identified ultrasonographically in only one of the three camels (33%) with uroperitoneum. It was impossible to pass a catheter because of the dorsal urethral recess and restrictive diameter of the urethra. 5. Conclusions In camels with abdominal distention, it would have been difficult to reach a confirmatory diagnosis without the use of ultrasonography. The actual causes of distension could not be verified with clinical certainty in the camels, whereas this was possible most of the time with ultrasonography, thus making the prognosis easier. In camels with trypanosomiasis, ultrasonography was highly effective in supporting the clinical and laboratory data and in excluding other conditions that lead to abdominal distension such as hepatic, renal or cardiac lesions. We believe that this approach would expedite the diagnosis. Because of the large body circumference of camels, the cause of intestinal obstruction can be determined by ultrasonography only rarely, which means that the cause is usually beyond the depth of penetration of the ultrasound transducer. In camels with ruptured urinary bladder, ultrasonographic examination of the abdomen has simplified the detection of either intact or perforated urinary bladder and the presence of uroperitoneum. Finally, it is suggested that ultrasonography be used in camels with abdominal distension to assist in differentiating gastrointestinal and urinary affections from other conditions.
Acknowledgements The authors would like to thank Dr Osama M. (Professor of Pathology) and Dr Hussein O. (Professor of Parasitology), Qassim University for their constructive comments. Appreciation is extended to Dr N. Peachy (Professor of English) Qassim University for language revising. This study was supported by the Deanship for Scientific Research (SR-D-010-078), Qassim University, Saudi Arabia. References Ali, A., Al-Sobayil, F.A., Tharwat, M., Hassanein, K.M., 2011. Ovarian hydrobursitis in female camels (Camelus dromedaries): biochemical, bacterial and protozoal evaluation. Theriogenology 75, 734–741. Bertone, A.L., Smith, D.F., 1984. Ruptured bladder in a yearling heifer. Journal of the American Veterinary Medical Association 184, 981–982. Blond, L., Buczinski, S., 2009. Basis of ultrasound imaging and the main artifacts in bovine medicine. Veterinary Clinics of North America: Food Animal Practice 25, 553–565. Braun, U., Marmier, O., Pusterla, N., 1995. Ultrasonographic examination of the small intestine of cows with ileus of the duodenum, jejunum or ileum. Veterinary Record 137, 209–215. Braun, U., 2005. Ultrasound as a decision-making tool in abdominal surgery in cows. Veterinary Clinics of North America: Food Animal Practice 21, 33–53. Divers, T.J., Crowell, W.A., Duncan, J.R., Whitlock, R.H., 1982. Acute renal disorders in cattle: a retrospective study of 22 cases. Journal of the American Veterinary Medical Association 181, 694–699. Fowler, M. E. 2010. Parasites. In Medicine and Surgery of Camelids, third Edition. Blackwell Publishing, Iowa, pp. 231-269. Gahlot, T. K. 1992. Urethral rupture and subcutaneous infiltration of urine in camels (Camelus dromedarius). In Proceeding of the First International Camel Conference, Dubai, pp., 353 – 355. King, A.M., 2006. Development, advances and applications of diagnostic ultrasound in animals. Veterinary Journal 171, 408–420. Köhler-Rollefson, I., Mundy, P., Mathias, E. 2001. Managing and treating camels. In A Field Manual of Camel Diseases: Traditional and Modern Healthcare for the Dromedary. ITDG publishing, London, pp., 1-67. Luckins, A. G. 1992. Protozoal disease of camel. In Proceedings of the First International Camel Conference, Dubai, pp., 23–27. Mohamed, T., Oikawa, S., 2007. Ultrasonographic characteristics of abdominal and thoracic abscesses in cattle and buffaloes. Journal of Veterinary Medicine Series A 54, 512–517. Mohamed, T., 2010. Clinicopathological and ultrasonographic findings in forty water buffaloes (Bubalus bubalis) affected with traumatic pericarditis. Veterinary Record 167, 819–824. Mohamed, T., Oikawa, S., 2011. Ultrasonographic evaluation of cattle and buffaloes with respiratory disorders. Tropical Animal Health and Production 43, 803–810. Olaho-Mukani, W., Mahamat, H., 2000. Trypanosomiasis in the dromedary camel. In: Gahlot, T.K. (Ed.), Selected Topics on Camelids. The Camelid Publishers, Chandan Sagar Well, Bikaner, India, pp. 255–270. Omer, O.H., Magzoub, M., Haroun, E.M., Mahmoued, O.M., Abdel-Hamed, Y.M., 1998. Diagnosis of Trypanosoma evaansi in Saudi Arabian camels (Camelus dromedaries) by the passive haemagglutination test and Ag-Elisa. Journal of Veterinary Medicine Series B 45, 627–633. Radostits, O. M., Gay, C. C., Hinchcliff, K. W., Constable, P. D. 2007. Veterinary Medicine. A Textbook of the Diseases of Cattle, Sheep, Pigs, Goats and Horses. 10th edn. Saunders. Ramadan, R.O., Abdin-Bey, M.R., Mohamed, G.E., 2008. Intestinal obstruction in camels (Camelus dromedaries). Journal of Camel Practice and Research 15, 71– 75. Roussel, A.J., Ward, D.S., 1985. Ruptured urinary bladder in a heifer. Journal of the American Veterinary Medical Association 186, 1310–1311. Skidmore, J.A., Adams, G.P., Billah, M., 2009. Synchronisation of ovarian follicular waves in the dromedary camel (Camelus dromedarius). Animal Reproduction Science 114, 249–255. Skidmore, J.A., Billah, M., 2011. Embryo transfer in the dromedary camel (Camelus dromedarius) using non-ovulated and ovulated, asynchronous progesteronetreated recipients. Reproduction and Fertility Development 23, 438–443. SPSS. Statistical Package for Social Sciences, SPSS Inc., Chicago, IL, USA CopyrightÓ for Windows, version 16.0: 2007. Tanwar, R.K., 1985. Intestinal obstruction due to phytobenzoars in a camel- a case report. Indian Journal of Veterinary Medicine 5, 31–32. Taylor, F. G. R., Brazil, T. J., Hillyer, M. H. 2010. Alimentary diseases. In Diagnostic Techniques in Equine Medicine. 2nd edn, Saunders, pp. 28-72. Wani, N.A., Skidmore, J.A., 2010. Ultrasonographic-guided retrieval of cumulus oocyte complexes after super-stimulation in dromedary camel (Camelus dromedarius). Theriogenology 74, 436–442. Wernery, U., Kaaden, O.R., 2002. Infectious Diseases in Camelids. Blackwell Science, Berlin, pp. 83–90.
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Research in Veterinary Science journal homepage: www.elsevier.com/locate/rvsc
Ultrasonographic evaluation of abdominal distension in 52 camels (Camelus dromedarius) Mohamed Tharwat a,1, Fahd Al-Sobayil a, Ahmed Ali a, Sébastien Buczinski b,⇑ a b
Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, Qassim University, Saudi Arabia Bovine Ambulatory Clinic, Departement des Sciences Cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Canada
a r t i c l e
i n f o
Article history: Received 28 April 2011 Accepted 12 July 2011
Keywords: Camel Intestinal obstruction Ruptured bladder Trypanosomiasis Ultrasonography
a b s t r a c t The purpose of this study was to assess the diagnostic value of ultrasonography in the evaluation of abdominal distension in 52 camels (Camelus dromedarius). The conditions included trypanosomiasis (n = 35), intestinal obstruction (n = 12) and ruptured urinary bladder (n = 5). Fifteen clinically normal camels were included as controls. Transabdominal and transrectal ultrasonography was carried out on all camels. In animals with trypanosomiasis, ultrasonographic findings included accumulation of massive amounts of hypoechoic abdominal fluids where liver, intestine, kidney, spleen and urinary bladder were imaged floating. Except in two cases of bile duct calcification and one of hepatic abscessation, no detectable abnormal sonographic lesions were detected while imaging the hepatic and renal parenchyma, and the heart and its valves and major blood vessels. In camels with intestinal obstruction, ultrasonographic findings included distended intestinal loops with markedly reduced or absent motility. In one camel, the intestinal lumen contained localised hyperechoic material that was consistent with a foreign body. Hypoechoic fluid with or without fibrin was seen between intestinal loops. In camels with ruptured urinary bladder, ultrasonographic findings included collapsed and perforated bladder, echogenic blood clots within the urinary bladder and peritoneal cavity, increased thickness of the bladder wall, floating intestines in hypoechogenic fluid and echogenic calculi within the urethra. Ultrasonography was considered a useful tool for the evaluation of dromedary camels with abdominal distension. Ó 2011 Elsevier Ltd. All rights reserved.
1. Introduction In camels, abdominal distention is a common clinical presentation (Köhler-Rollefson et al., 2001; Fowler, 2010). There are many conditions in which abdominal distension has been reported. These conditions include trypanosomiasis, cardiomyopathy, hypoprotenaemia, hepatic and renal diseases, septic peritonitis and diffuse malignant neoplasia (Köhler-Rollefson et al., 2001). Other causes of abdominal distention include uroperitoneum due to ruptured bladder, intestinal obstruction, ruminal tympany, foreign bodies, vagus indigestion and advanced pregnancy (Fowler, 2010). Ultrasound has been widely used lately in veterinary medicine. Ultrasound imaging has the advantage over radiology of offering better contrast resolution and acquiring slice images of organs in different planes in real time—all with portable and noninvasive
⇑ Corresponding author. E-mail address: [email protected] (S. Buczinski). Permanent address: Department of Animal Medicine, Faculty of Veterinary Medicine, Zagazig University, Egypt. 1
0034-5288/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.rvsc.2011.07.009
and nonionising equipment (Blond and Buczinski, 2009). During the past 15 years, the use of ultrasonography has become widespread in veterinary medicine through its ease of application in virtually every facet of veterinary medicine and for almost all species (King, 2006). The procedure is a reliable tool to detect various types of disease in different farm animal species (Braun, 2005; Mohamed and Oikawa, 2007; Mohamed, 2010; Mohamed and Oikawa, 2011). In camel practice, the application of ultrasonography is still limited. It is mostly used for reproductive examination and for pregnancy diagnosis (Skidmore et al., 2009; Wani and Skidmore, 2010; Skidmore and Billah, 2011). In the field of internal medicine, however, sonographic studies have not been reported in camels with either abdominal or thoracic disorders. Ultrasonography is of particular interest as an ancillary tool for the diagnosis of common causes of colic and abdominal distension in cattle and horses (Radostits et al., 2007; Braun, 2005; Taylor et al., 2010). In our clinic, abdominal distension in camels is a common reason for referral. The present study was designed to investigate the ultrasonographic findings in camels with abdominal distension as a main clinical sign. To the best of the authors’ knowledge, this is the first study that uses ultrasound to evaluate abdominal distension in dromedary camels.
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vitamin B1, vitamin B12 and copper containing agent (Fercobsang, Vetoquinol, LURE Cedex, France, 20 ml IM). Camels with partial intestinal obstruction due to ruminal foreign bodies were scheduled for rumenotomy.
2. Materials and methods 2.1. Animals, history and physical examination Fifty-two camels (Camelus dromedarius), aged from 6 months to 12 years, were examined in the present study. Cases were primarily referred to determine the cause of abdominal distension, and these animals had also inappetance, loss of body condition, ventral or presternal oedema, urine retention and vomition. Duration of illness ranged from 2 days to 5 weeks. The passive hemagglutination test showed that 35 camels (70%) were positive for Trypanosoma evansi. Thirty-two of the positive camels (91%) were females, nine (28%) lactating. The remaining camels included cases of intestinal obstruction (n = 12) and ruptured urinary bladder (n = 5). Fifteen apparently healthy camels (age: 2.5 ± 1.1 year) were enrolled in this study as controls. Animals were examined at the Veterinary Teaching Hospital, Qassim University, Saudi Arabia, between 2007 and 2011. Clinical examinations of camels were carried out as previously described (Köhler-Rollefson et al., 2001). This included general behavior and condition, auscultation of the heart, lungs, rumen and intestine, measurement of heart rate, respiratory rate and rectal temperature, swinging auscultation, percussion auscultation of both sides of the abdomen and rectal examination.
2.3. Haematological and biochemical analyses Two blood samples were collected from each camel: one placed in a plain tube, and the other in an EDTA tube. Direct smear, buffy coat and haematological examinations (haematocrit, haemoglobin and total and differential leukocyte count) were carried out on the EDTA, the later with the use of an automated veterinary haematological analyser (Vet Scan HM5, ABAXIS, Hungary). Samples in plain tubes were centrifuged at 1200g for 10 min, and serum samples were harvested and stored at 20 °C for future analysis. Commercial kits were used to determine the concentrations of total protein, albumin, glucose, blood urea nitrogen (BUN) and creatinine. The activities of aspartate aminotransferase (AST) and c-glutamyl transpeptidase were measured in serum samples using an automated biochemical analyser (Biosystems A15, Spain). Globulin concentration was obtained by calculating the difference between total protein and albumin. 2.4. Serological detection of T. evansi
2.2. Treatment and follow-up After the initial examination, camels with trypanosomiasis were injected subcutaneously with two doses of a trypanosomicide, AlquinÒ-1.5 (Quinapyramine sulphate, Vetnex, Riyadh, Saudi Arabia, 5 mg/kg BW) two weeks apart, and intramuscularly (IM) with five successive daily doses of an antioedematous – antiinflammatory agent, DiurizoneÒ, (hydrochlorothiazide and dexamethasone, Vetoquinol, LURE Cedex, France, 12 ml IM). Animals were also injected with five successive daily doses of iron, cobalt,
Serum samples were also tested for T. evansi antibodies by passive haemaggluination test as previously described (Omer et al.,
Table 1 History and clinical findings in 52 camels with abdominal distension. Clinical findings
*
Number (%) of camels manifesting clinical signs
Trypanosomiasis (n = 35) Weight loss Abdominal distension Ventral and subcutaneous presternal oedema Weak and irregular gastric contractions Inappetance Fever Recumbency Diarrhoea Decreased milk production
13 (37) 35 (100) 25 (71) 31 (89) 33 (94) 1(3) 5 (14) 9 (26) 9 (100)*
Intestinal obstruction (n = 12) Sunken eyes Vomition Inappetance Ruminal stasis Abdominal distension
11 10 12 12 12
Ruptured urinary bladder (n = 5) Sunken eyes Colicky pain Anorexia Ruminal stasis Abdominal distension Abdominocentesis (red urine) Head oedema Anuria Dribbling
3 3 5 3 5 2 2 2 3
(92) (83) (100) (100) (100)
(60) (60) (100) (60) (100) (40) (40) (40) (60)
All the nine lactating camels examined in this study had a decreased milk production.
Fig. 1. Clinical manifestation in 2 camels with chronic trypanosomiasis. Image (a) shows severe abdominal distension and image (b) shows presternal oedema (asterisks).
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1998). Briefly serum samples were diluted in Tris buffer solution, pH 8.0. Each serum sample was tested using the microtitre technique. Two-fold dilutions of sera from 1:8 to 1: 14,096 were made in V-bottomed microtitre plates (Greiner – Germany). After dilution the T. evansi/red blood suspension was added and incubated at room temperature for 3 h. Sera from uninfected and infected camels were used as negative and positive controls, respectively. Samples showing agglutination at 1:16 were considered positive for T. evansi infection (Ali et al., 2011). 2.5. Ultrasonographic examination
Fig. 2. Vomition in a camel with intestinal obstruction.
Ultrasonographic examination of control and sick camels was carried out in sternal recumbency using 3.5 and 5.0 MHz transducers (SSD-500, Aloka, Tokyo, Japan). The procedure was carried out
Fig. 3. Findings of rumenotomy in camels with partial intestinal obstruction. Together with hair balls (a, b, asterisks), plastic bags and ropes (b, c, white and black arrows) and wires, glass, and other metal objects (d) were discovered.
Table 2 Haematological and biochemical findings (mean ± SD) in 52 camels with abdominal distention compared to controls. Parameters Haematocrit (%) Haemoglobin (g/dL) Leukocyte count (/lL) Neutrophils (/lL) Lymphocytes (/lL) Total protein (g/dL) Albumin (g/dL) Globulin (g/dL) AST (U/L) GGT (U/L) BUN (mg/dL) Creatinine (mg/dL) Glucose (mg/dL)
Trypanosomiasis (n = 35) *
20 ± 4 10 ± 4 15,400 ± 5241** 9086 ± 6251 4928 ± 2589 5.2 ± 2.2* 2.0 ± 1.4** 3.2 ± 0.6 136 ± 88* 52 ± 9 35 ± 11 1.6 ± 0.4 110 ± 40
Intestinal obstruction (n = 12) 24 ± 10 16 ± 5 19,725 ± 1431*** 12,624 ± 8876** 5129 ± 6115 7.2 ± 2.5 3.4 ± 0.9 3.8 ± 0.9 304 ± 154** 32 ± 15 112 ± 72** 1.5 ± 0.5 157 ± 36*
AST = aspartate aminotransferase; GGT = c-glutamyl transferase; BUN = blood urea nitrogen. P < 0.05. * P < 0.01. * P < 0.001 *
Uroperitoneum (n = 5) *
45 ± 11 18 ± 6* 38,289 ± 16,528*** 34,843 ± 17,592*** 2680 ± 3064 7.5 ± 1.2 3.2 ± 1.5 4.3 ± 1.1 88 ± 27 52 ± 13 195 ± 86*** 3.5 ± 2.7** 168 ± 29*
Controls (n = 15) 32 ± 1.4 12 ± 3 8250 ± 2284 7900 ± 1800 3800 ± 1800 7.9 ± 0.4 4.2 ± 0.4 3.7 ± 0.5 69 ± 44 44 ± 22 17 ± 10 1.3 ± 0.2 61 ± 19
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Fig. 4. Flowchart summarising the key ultrasonographic findings that allow the differentiation of the three examined conditions.
Table 3 Ultrasonographic findings in 52 camels with abdominal distention. Ultrasonographic findings
Number (%) of camels
Trypanosomiasis (n = 35) Ascites Oval to round caudal vena cava Distended portal and hepatic veins Bile duct calcification Hepatic abscessation Hydropericardium Hydrothorax Splenomegaly Hepatomegaly
34 (97) 7 (20) 6 (17) 2 (6) 1 (3) 7 (20) 7 (20) 7 (20) 7 (20)
Intestinal obstruction (n = 12) Distended intestinal loops Reduced or absent intestinal motility Intestinal foreign bodies Hypoechoic fluid with fibrin between intestinal loops Hypoechoic fluid without fibrin between intestinal loops
12 (100) 12 (100) 1 (8) 6 (50) 4 (33)
Ruptured urinary bladder (n = 5) Echogenic blood clots within the urinary bladder and peritoneal cavity Increased thickness of bladder wall Uroperitoneum Urethral calculation Perforated bladder wall
Fig. 5. Abdominal ultrasonogram in a camel with trypanosomiasis. Image was taken from the 10th right intercostal space using a 3.5 MHz sector transducer. The liver appears hyperechogenic on ultrasonograms and is floating in a hypoechoic fluid. 1 = hepatic parenchyma; 2 = lung shadow; 3 = anechoic abdominal fluid; 4 = small intestine; DS = dorsal; VT = ventral.
2 (40) 2 5 2 1
(40) (100) (40) (20)
twice, one before, and three weeks after, treatment. Animals were sedated using xylazine 2% (0.3 mg/kg BW IV, Alcomed, Holland). Hair was clipped and shaved on both sides of the abdomen and thorax from the dorsal midline to linea alba. Camels were examined percutaneously and transrectally. After the application of transmission gel to the transducer, the camel was examined starting from the caudal abdomen and extending forward to the third intercostal space on both sides of the thorax. The abdominal viscera including the abdomen, peritoneum, stomachs, spleen, small and large intestines, liver, pancreas and kidneys were imaged. In the thoracic cavity, the lungs, heart and its major blood vessels and the mediastinal region were scanned. Due to a poor prognosis, camels with complete intestinal obstruction and/or ruptured urinary bladder were euthanized and necropsied. 2.6. Statistical analysis Data were presented as means ± SD and the analysis was conducted using SPSS, 2007 program, version 16.0. Haematological
Fig. 6. Hepatic ultrasonogram in a camel with trypanosomiasis. Images were taken from the right 11th intercostal space. Calcification of the bile ducts (white arrow) and hepatic abscessation (black arrow) was detected. PV = portal vein; AS = acoustic shadowing; AE = acoustic enhancement; AB = abscess.
and biochemical data of diseased and control camels were compared, using repeated measures of ANOVA. The level of significance was set at P < 0.05. 3. Results 3.1. Clinical presentations Of the 52 camels with distended abdomen, 35 (67%) had trypanosomiasis, 12 (23%) had intestinal obstruction and five (10%) had a ruptured urinary bladder. The history and clinical findings of the 52 camels with abdominal distention are summarised in Table 1. The most prominent clinical presentations seen in camels
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Fig. 7. Ultrasonographic findings in camels with intestinal obstruction. Ultrasonographic findings included distended intestinal loops with markedly reduced or absent motility (A, B, C). Image D shows a hypoechoic fluid with fibrin (white arrow) between intestinal loops; black arrow points to the intestinal wall. In one camel with partial obstruction, the intestinal lumen contained localised hyperechoic material consistent with foreign body (E). Corrugated ruminal wall was scanned in one camel with intestinal obstruction (F). IL = intestinal loops; FB = foreign body; F = fluid; DS = dorsal; VT = ventral.
with trypanosomiasis were inappetance, weak and irregular ruminal contractions, weight loss, abdominal distension and ventral and subcutaneous presternal oedema (Fig. 1). On clinical examination, ascites was detected by a fluid thrill on ballottement, by fluid sounds on succussion, or by the demonstration of excess fluid in the peritoneal cavity by abdominocentesis. On admission, examination of blood smears from the affected camels showed that the
parasites were detected in only one camel (3%). Twenty days after treatment, abdominal distension and ventral and presternal oedema disappeared in 23 (66%) cases. A telephone-based follow-up recorded that all operated animals made a full recovery. Unfortunately, we could not contact the owners of the other 12 (33%). Partial and complete intestinal obstructions were observed in five and seven camels, respectively. When presented, all cases
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Fig. 8. Ultrasonographic images in 2 camels with ruptured urinary bladder. Image A shows blood clot (BC) within the urinary bladder and image B shows blood clot (BC) within the abdomen. Note the thickened bladder wall (1). UB = urinary bladder; UP = uroperitoneum.
were depressed with reduced gastrointestinal motility. The abdomen was distended bilaterally in all affected camels. The eyes were sunken and the animals were recumbent, with vomition in ten (Fig. 2). If stimulated to stand, camels would struggle and wander in an ataxic manner. In camels with partial obstruction, rectal examination revealed the presence of very hard, spiny faecal particles and distended viscera. In animals with complete obstruction, rectal findings showed a small amount of black faeces stained with mucus or no faeces at all. One camel with complete obstruction died 24 h after admission. In animals with partial intestinal obstruction, the owners reported that their animals had been chewing foreign bodies, especially plastic bags and ropes. In these cases, rectal examination revealed the presence of small amounts of hard feces and distended rumen. Rumenotomy performed in these cases showed presence of plastic bags, ropes, glass, hairballs, wires and nails (Fig. 3). In the five camels with ruptured urinary bladder, attacks of colic and abdominal distention were recorded. One animal with severe colic has died shortly after admission to the hospital. Rectal examination revealed a collapsed bladder and abdominocentesis revealed the presence of urine. Bloody urine was collected from the abdomen of two camels and in each case the head was oedematous. 3.2. Haematological and biochemical findings Compared to control animals, those with trypanosomiasis showed reduced packed cell-volume, neutrophilic leukocytosis, a reduction in haemoglobin concentration and presence of a macrocytic hypochromic anaemia, hypoproteinaemia and hypoalbuminaemia. In camels with intestinal obstruction, laboratory data included neutrophilic leukocytosis, elevated AST activity and hyperglycaemia. In animals with a ruptured bladder, neutrophilic leukocytosis, hyperproteinaemia, hyperglycaemia and elevated concentrations of BUN and creatinine were observed. Compared with the controls, other measured serum values did not differ significantly (Table 2).
3.3. Ultrasonographic findings Fig. 4 summarises ultrasonographic findings in camels with trypanosomiasis, intestinal obstruction and ruptured urinary bladder. Ultrasonographic findings in the 52 camels with abdominal distention are summarised in Table 3. In camels with trypanosomiasis, ultrasonographic findings included accumulation of massive amounts of abdominal fluid, where liver and intestines were imaged floating in a hypoechoic fluid (Fig. 5). Transrectal examination also revealed the presence of excessive amounts of anechoic fluid where the urinary bladder and other pelvic organs were also floating. Other ultrasonographic findings included oval to round caudal venae cavae, distended hepatic and portal veins, bile duct calcification and hepatic abscessation (Fig. 6), which was confirmed at necropsy. Ultrasonographic examination of the thorax revealed the presence of anechoic fluid. Compared to the controls, the liver was imaged beyond the 12th rib and at the right ventrum indicating organ enlargement. Except for two cases of bile duct calcification and one of hepatic abscessation, there were no detectable abnormal sonographic findings detected while imaging the hepatic and renal parenchyma and heart, and its valves and major blood vessels. Three weeks after treatment, twenty-three camels (66%), showed no fluids imaged in the peritoneum, pericardium or pleura. The caudal venae cavae, hepatic and portal veins appeared normal. Compared to the control animals (2.62 ± 0.47 cm), those with intestinal obstruction had ultrasonographic findings which included distended small intestinal loops (5.9 ± 1.8 cm) with markedly reduced or absent motility. In one camel with partial obstruction, the intestinal lumen contained localized hyperechoic material consistent with a foreign body. Hypoechoic fluid with or without fibrin was seen between intestinal loops (Fig. 7). In two camels with a ruptured bladder, ultrasonographic findings included presence of echogenic blood clots within the urinary bladder and peritoneal cavity, with increased thickness of the bladder wall (Fig. 8) that was confirmed at necropsy. Floating intestines in a hyperechogenic fluid were imaged in two camels. In the
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Fig. 9. Ultrasonographic images in a six-month old camel-calf with ruptured urinary bladder. Image A shows urinary calculi within the urethra (white arrow) with acoustic shadowing (arrowhead). Image B shows perforated urinary bladder (white arrow) and image C show floating intestines in uroperitoneum. UB = urinary bladder; DS = dorsal; VT = ventral.
remaining case, floating intestines in a hypoechogenic fluid, echogenic calculi within the urethra and a perforated bladder were imaged clearly in a 6-month-old male camel calf (Fig. 9). 3.4. Postmortem findings Table 4 summarises the postmortem findings in 24 camels with abdominal distension. In camels with trypanosomiasis, 23 animals (66%) recovered after treatment, but 12 (34%) did not, their conditions deteriorated and they were killed and necropsied. Necropsy findings included emaciation, subcutaneous oedema, ascites, hepatomegaly, splenomegaly, hydrothorax and hydropericardium. In
camels with complete intestinal obstruction, necropsy findings included presence of constricted intestines around enteroliths, paralytic ileus and mesenteric torsion (Fig. 10). In camels with ruptured bladder, necropsy findings included uroperitoneum, abdominal haemorrhages and perforated bladders (Fig. 11). 4. Discussion In camels, trypanosomiasis is usually chronic but can be acute with a 90% mortality rate if not treated (Luckins, 1992). Clinical signs and lesions caused by T. evansi in camels are unreliable for a definitive diagnosis (Olaho-Mukani and Mahamat, 2000). In the
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Table 4 Postmortem findings in 24 camels with abdominal distention. Postmortem findings Trypanosomiasis (n = 12) Emaciation Subcutaneous edema Ascites Hydrothorax Hydropericardium Hepatomegaly Splenomegaly Complete Intestinal obstruction (n = 7) Mesenteric constricted intestines around enteroliths Paralytic ileus Mesenteric torsion Ruptured urinary bladder (n = 5) Uroperitoneum Perforated bladder Abdominal haemorrhages
Number (%) of camels showing lesions 10 (83) 9 (75) 12 (100) 7 (58) 7 (58) 7 (58) 7 (58) 3 (43) 3 (43) 1 (14) 5 (100) 5 (100) 2 (40)
Fig. 11. Postmortem findings in a six-month old camel-calf with ruptured bladder. Image A shows uroperitoneum and image B shows perforated urinary bladder wall (black arrow).
Fig. 10. Postmortem findings in a camel with intestinal obstruction. Mesenteric torsion was the most outstanding finding.
present study, trypanosomiasis was suspected clinically in camels showing a chronic weight loss, subcutaneous oedema and ascites. These clinical findings were in agreement with those of other reports (Wernery and Kaaden, 2002). Clinical manifestations including chronic weight loss, subcutaneous oedema and ascites may be associated with trypanosomiasis but not necessarily indicative of the disease in camels (Fowler, 2010). In cases with suspected ascites, a full clinical examination, including a rectal examination and abdominal percussion/ballottement, help to rule out a number of other causes of abdominal distension. The detection by rectal examination of viscera floating in a fluid medium, and a fluid wave on abdominal ballottement suggests the presence of ascites (Radostits et al., 2007). Finding the parasite in the peripheral blood of infected camels may be highly problematic because of low numbers of the organisms and fluctuating parasitaemia. The development of a suitable serological ELISA test resulted in effectively decreasing the economic losses associated with trypanosomiasis; other DNA technologies are being used in endemic countries (Fowler, 2010). In this study, definitive diagnosis was made on the basis of detecting trypanosomes in a blood smear or antibodies in serum. In camels with trypanosomiasis, ultrasonography of the abdomen confirmed the presence of free abdominal fluid. Non-inflamma-
tory ascites due to other disorders, such as right-sided cardiac insufficiency, hepatic and renal disorders, could be ruled out based on the results of the clinical and ultrasonographic findings. The differential diagnosis also included chronic parasitism. Intestinal obstruction is relatively rare in camels (Köhler-Rollefson et al., 2001; Fowler, 2010). Massive intestinal parasite infestation, plastic foreign bodies and enlarged mesenteric lymph nodes may all cause intestinal obstruction (Ramadan et al., 2008). Camels suffering from pica usually eat hair, leading to the formation of phytobezoars and trichobezoars that may reach the intestine causing obstruction (Tanwar, 1985). Other causes of intestinal obstruction include impaction of the spiral colon, dilatation and torsion of the caecum and strangulation of the intestine in inguinal hernia (Köhler-Rollefson et al., 2001). Ultrasonographic findings, such as changes in luminal diameter, motility and intestinal wall thickness, have been used to diagnose intestinal problems in other ruminant species (Braun et al., 1995). In this study, the most important ultrasonographic finding in camels with either partial or complete intestinal obstruction was dilation of the small intestine with a marked reduction or absence of intestinal motility. Fluid was seen between loops of intestine. Accumulation of ingesta in the omasum/abomasum chamber was detected, some of which also had accumulation of ingesta in the rumen. When taken together, these findings were indicative of ileus (Braun, 2005). Similar ultrasonographic findings were reported in cows with ileus attributable to other causes (Braun et al., 1995), and rarely was the cause determined. In this study, we could determine the cause
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of ileus and make a definitive diagnosis of intestinal obstruction in only one of the seven camels (14%). We could also see the foreign body in the intestine in one of the four operated animals (25%). Failure to make an accurate diagnosis may be attributed to the large abdominal circumference in examined camels. Because the depth of penetration of the ultrasound waves 20 cm, only a small part of the intestinal tract is accessible to ultrasonography. The cause of mechanical obstruction is usually beyond the depth of penetration of the ultrasound transducer. Thus, the veterinarian must decide whether exploratory laparotomy is indicated on the basis of the results of the clinical examination, haematological and biochemical analyses and ultrasonography, as well as the value of the camel. Urolithiasis is common as a subclinical disorder among ruminants raised in management systems where the ration is composed primarily of grain, or where animals graze certain types of pasture. In these situations, 40–60% of the animals may form calculi in their urinary tract (Radostits et al., 2007). Rupture of the urinary bladder and subsequent uroperitoneum is a common problem in cattle, and in males, urolithiasis is the underlying cause in the majority of cases (Divers et al., 1982; Bertone and Smith, 1984). Uroperitoneum may be caused by trauma when the bladder is distended or from rupture of the bladder following urethral obstruction. Urine in the abdomen may not arise only from a single or multiple tears in the bladder wall, but also from seepage through the thinly stretched bladder wall in an over-distended bladder (Fowler, 2010). A ruptured urethra has been reported in camels (Gahlot, 1992; Roussel and Ward, 1985). After the bladder ruptures, uroperitoneum results in a series of abnormalities that arise from failure of the excretory process combined with solute and fluid redistribution between the peritoneal fluid and extracellular fluid. Osmotic pressure from hypertonic urine promotes the movement of extracellular water into the peritoneal cavity resulting in clinical dehydration (Radostits et al., 2007). Bladder rupture then leads to gradual development of ascites from uroperitoneum, ruminal stasis, constipation and depression. Finally, uraemia may take 1– 2 weeks to develop to the point where euthanasia is necessary (Roussel and Ward, 1985). Calculus was identified ultrasonographically in only one of the three camels (33%) with uroperitoneum. It was impossible to pass a catheter because of the dorsal urethral recess and restrictive diameter of the urethra. 5. Conclusions In camels with abdominal distention, it would have been difficult to reach a confirmatory diagnosis without the use of ultrasonography. The actual causes of distension could not be verified with clinical certainty in the camels, whereas this was possible most of the time with ultrasonography, thus making the prognosis easier. In camels with trypanosomiasis, ultrasonography was highly effective in supporting the clinical and laboratory data and in excluding other conditions that lead to abdominal distension such as hepatic, renal or cardiac lesions. We believe that this approach would expedite the diagnosis. Because of the large body circumference of camels, the cause of intestinal obstruction can be determined by ultrasonography only rarely, which means that the cause is usually beyond the depth of penetration of the ultrasound transducer. In camels with ruptured urinary bladder, ultrasonographic examination of the abdomen has simplified the detection of either intact or perforated urinary bladder and the presence of uroperitoneum. Finally, it is suggested that ultrasonography be used in camels with abdominal distension to assist in differentiating gastrointestinal and urinary affections from other conditions.
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