ULTRASONOGRAPHIC DIAGNOSIS OF OBSTRUCTIVE UROLITHIASIS IN CATTLE AND BUFFALO

Document Type : Research article

Author

Dept. of Surgery, Fac. Vet. Med., Assiut University.

Abstract

The present study aimed to evaluate the efficacy of ultrasound in diagnosis of obstructive urolithiasis and rupture of the urinary bladder in cattle and buffalo. The study was carried out on 30 non castrated cattle and buffaloes males (19 cattle and 11 buffaloes), suffering from obstructive urolithiasis. Case history and clinical signs were recorded. Diagnosis was confirmed by radiography and surgery. Ultrasonographic examination showed urethral pulsation and urethral dilatation in front of the seat of obstruction as well as the changes in the wall thickness of the urinary bladder and urethra due to rupture, inflammation or obstruction, Ultrasound allowed diagnosis of cystitis in 19 cases, where the bladder wall was thickened, and the urine was turbid. Ruptured urinary bladder
was visible in 12 cases. The site of the rupture in the urinary bladder was visible in 4 cases. Free abdominal fluid due to rupture of the urinary bladder was visible in 20 cases. In 8 of these cases, the urinary bladder healed spontaneously after rupture and was intact and distended with urine during the ultrasound examination.

Keywords


Assiut Vet. Med. J. Vol. 52 No. 110 July 2006

Dept. of Surgery, Fac. Vet. Med. Assiut University.

ULTRASONOGRAPHIC DIAGNOSIS OF OBSTRUCTIVE UROLITHIASIS

IN CATTLE AND BUFFALO (With One Table and 10 Figures)

By MAGDA M. ALI (Received at 18/6/2006)

تخطيط الصدى لتشخيص التحصر البولي الأنسدادي في الأبقار والجاموس ماجدة محمود على

حالات انسداد مجري

هذة الدراسة إلي تقييم دور الموجات فوق الصوتية في تسخيص

تهدف البول والمثانة في الأبقار والجاموس. اجريت الدراسة على عدد ۳۰ حيوان غير مخصی (19 أبقار و ۱۱ جاموس) تعاني من انسداد مجرى البول بالحصاوي. وقد تم تسجيل التاريخ

عن طريق اجراء القحص

المرضى والأعراض الاکلينيکية لکل حالة. تم التأکد من التشخيص الأشعاعي والفحص بتخطيط الصدی. امکن باستخدام تخطيط الصدى رؤية نبض مجری البول والتمدد فية نتيجة الانسداد کذلک التغير في سمک جدار مجرى البول أمام مکان الأنسداد اضافة الى التغير الحادث في سمک جدار المثانة ووجود ترسيبات بالبول في حالات التهابات المثانة. کذلک أمکن بأستخدام تخطيط الصدى تشخيص ۱۹ حالة التهاب المثانة، ۱۲ حالة انفجار المثانة وفي أربعة من هذة الحالات امکن رؤية مکان الانفجار وامکن رؤية وجود سوائل في البطن في ۲۰ حالة وفي ۸ حالات کان انفجار المثانة قد ألتام زاتيا.

SUMMARY

The present study aimed to evaluate the efficacy of ultrasound in diagnosis of obstructive urolithiasis and rupture of the urinary bladder in cattle and buffalo. The study was carried out on 30 non castrated cattle and buffaloes males (19 cattle and 11 buffaloes), suffering from obstructive urolithiasis. Case history and clinical signs were recorded. Diagnosis was confirmed by radiography and surgery. Ultrasonographic examination showed urethral pulsation and urethral dilatation in front of the seat of obstruction as well as the changes in the wall thickness of the urinary bladder and urethra due to rupture, inflammation or obstruction, Ultrasound allowed diagnosis of cystitis in 19 cases, where the bladder wall was thickened, and the urine was turbid. Ruptured urinary bladder

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was visible in 12 cases. The site of the rupture in the urinary bladder was visible in 4 cases. Free abdominal fluid due to rupture of the urinary bladder was visible in 20 cases. In 8 of these cases, the urinary bladder healed spontaneously after rupture and was intact and distended with urine during the ultrasound examination.

Key words: Cattle, Buffalo, ultrasonography, obstructive urolithiasis

INTRODUCTION

Urolithiasis is a common affection in cattle and buffalo, which leads to urinary blockage (Tantawy 1985, Payne 1989, Radostitis et al., 2000, Loretti et al., 2003, Misk and Semieka 2003). Urolithiasis appears to affect both sexes, but urinary blockage is an important problem mainly in males. Urinary calculi formation usually results from a combination of physiologic, nutritional and managemental factors. It is mainly attributed to excessive or unbalanced intake of minerals (Larson 1996, Lotfia et al., 1999, Radostitis et al., 2000).

Clinical symptoms of urinary tract obstruction may be associated with partial or complete urethral occlusion. Animals suffering from partial obstruction dribble blood-tinged urine after prolonged, painful attempts of urination. With complete obstruction, animals exhibit tenesmus, tail twitching, weight shifting, colic, inappetence, depression, and urethral pulsation ventral to the anus. The common sequela of the complete urethral obstruction is the rupture of the urinary bladder and/or the urethra resulting in death of the animal due to uremia in 5 to 7 days (Radostitis et al., 2000, Loretti et al., 2003).

Diagnosis of urolithiasis and rupture of the urinary bladder and urethra in cattle, sheep and goat is based mainly on the clinical symptoms, and increase in the peritoneal concentration of createnine 1.5 - 2 times than in serum. Systemic injection of dye that is eliminated by the kidneys, injection of dye into the urinary bladder followed by recovery in peritoneal fluid and injection of air in the urinary bladder during assaulting the abdomen (Cartee et al., 1980) are concerned to be additional tools for diagnosis.

Imaging techniques as plain and contrast radiography are usually used in evaluation of the urinary tract lesions in dogs, cats, small and large ruminants and swine (Palmer et al., 1998, Misk and Semeika 2003, Kyles et al., 2005). In small animals, ultrasound examination was successfully used in diagnosis of many urinary disorders as patent

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urachus, urachal sinus, cystitis, urolithiasis, tumors, and rupture of the urinary bladder (Cartee et al., 1980, Le'veille' 1998, Kyles et al., 2005). In ruminants, ultrasound was used in examination of the upper urinary tract as the kidney blood flow and renal function in cows (Braun 1993, Loretti et al., 2003), as well as in diagnosis of urethral dilatation in calf (Geccelep and Alkan 2000).

This study aimed to evaluate the efficacy of ultrasound examination in diagnosis of urolithiasis and urinary bladder rupture in cattle and buffaloes.

MATERIALS and METHODS

The present study was carried out on 30 non castrated male animals, (19 cattle and 11 buffaloes) with age ranging from 2.5 - 18 months. The animals were submitted to the Veterinary Teaching Hospital of Assiut University with a complaint of partial or complete urine retention for a period ranging from 1- 25 days. Thirteen animals suffered from partial obstruction (9 cattle & 4 buffaloes), dribbled blood-tinged urine after prolonged painful attempts to urinate. Seventeen animals were presented with complete urethral obstruction (10 cattle & 7 buffaloes). Five of theses animals showed tenesmus, raising the tail, depression and urethral pulsation ventral to the anus. In the other 12 animals, there were no signs of colic at time of presentation but they showed ventral distention of the abdomen and anorexia. Abdominal paracentesis was made in these cases.

Plain, latero-lateral radiographic examination of the urinary bladder and the pelvic urethra was done for all cases, the animals were laid in lateral recumbency with the uppermost hind limb pulled forward. Sedation of the animals before radiography was not needed

Ultrasound examination for the urinary bladder and the urethra was done using a real time, B-mode diagnostic ultrasound scanner (Pie Data Medical Company, Maastricht, The Netherlands, 100 LC) equipped with linear array 6/8 MHz transducer. Transrectal examination of the urinary bladder and the urethra was done for all presented cases in standing position without sedation. The penile urethra was examined percutaneously. In the perineal and prescrotal areas copious amount of gel was needed to allow easier examination of the urethra. Diagnosis was confirmed with urethrostomy and laparotomy. The size and shape of the obtained stones were recorded.

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RESULTS

Diagnosis of urolithiasis with or without rupture of the urinary bladder was based on the history, clinical signs, physical examination, radiography and ultrasound examinations. Clinical signs varied according to the duration and degree of obstruction, and the general health condition of the animal. Physical examination by palpation of the penile urethra allowed detection of the site of obstruction in the urethra in 12 cattle but not in buffalo due to the relative smaller size of the calculi in buffaloes.

Transrectal palpation could not be performed in 20 of the examined animals. The age of these animals ranged from 2.5 - 9 months. In all cases that did not suffer from ruptured bladder, urethral pulsation was felt under the anus. In cases of ruptured urinary bladder, abdominal paracentesis revealed clear yellowish fluid, which was identified by its odour as urine.

The seat of obstruction with the calculi in all cases was at the distal part of the sigmoid flexure in both animal species. In 15 examined cattle bulls, the calculus was single and pea size (Fig. 1). However, in buffaloes they were small, and multiple grapes-like sandy calculi.

Radiography was helpful in diagnosis of urethral obstruction with urethral calculi especially in cattle as the size of the urethral calculus was bigger than that in buffaloes. In 8 of the examined cases (3 cattle and 5 buffaloes), radiographic examination was not diagnostic for the presence of urethral calculi which was detected by ultrasound examination and during surgery.

In ultrasonographic examination, urethral pulsation and urethral dilatation in front of the seat of obstruction as well as the changes in the wall thickness of the urinary bladder and urethra due to rupture, inflammation or obstruction were easily seen in all cases.

The body and neck of the urinary bladder and the pelvic urethra were easily examined via transrectal ultrasound examination. The penile urethra was examined percutaneously and was difficult to be examined at the level of the sigmoid flexure caudal to the scrotum especially in fattened animals. The diameter and the wall thickness of the urinary bladder and the urethra could be measured. Cystitis was diagnosed in 19 cases, in which the wall of the bladder was thickened, and the urine was turbid (Fig. 2). Rupture of the urinary bladder was diagnosed in 12 cases (Fig. 3 & 4).

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The site of rupture in the urinary bladder was visible in 4 cases using ultrasound examination. Free abdominal fluid due to rupture of the urinary bladder was visible in ultrasound examination in 20 cases (Fig. 3& 4). In 8 of these cases, the urinary bladder was intact and distended with urine.

In two cases suffered from complete urine retention, radiographic examination was not diagnostic. However, ultrasonographic examination of the urinary bladder and the urethra in these two cases showed thickening in the wall of the urinary bladder and the urethra, in addition to obstruction of the pelvic urethra. This was reflected by the presence of tissue density in the lumen of the urethra and narrowing of the urethral lumen (Fig. 5 & 6). The owners of these cases reported that the animals showed for one week before presentation blood drops in the urine. During surgery of these cases the urethral lumen was dark red in colour and was filled with tissue debris (Table 1).

The stones visible via ultrasound in cattle were single, pea sized stones; 0.5-1.5 cm in length (Fig. 7& 8), while in buffalo they were small, multiple and grapes like stones (Fig. 9). These findings were confirmed during surgery. The urethral lumen was widened before the site of obstruction and narrowed behind it (Fig. 10), the urethral pulsation due to the obstruction was also visible during the ultrasound examination.

Table 1: Affections diagnosed by ultrasonographic examination

Animal

Cystitis

Ruptured urinary bladder

urethritis

urolithiasis

Cattle

10

21

Buffalo

8

Total

19

12

29

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NEW

FIL

Abd. fiuid

Abd. fuid

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LEGENDS OF FIGURES

Fig. 1: Shape of stones collected from the urethra of cattle Fig. 2: Show turbidity of urine and thickening in the wall of the urinary

bladder Fig. 3&4: Rupture of the urinary bladder, with free abdominal fluid, in

fig. (3) The urinary bladder appeared slightly distended, in fig.

(4) It appeared completely empty and flattened Fig. 5: Tissue density in the lumen of the neck of the urinary bladd

and the pelvic urethra (white arrow) Fig. 6: Narrowing of the urethral lumen with presence of tissue density

inside the lumen of the penile urethra (white arrow) Fig. 7 & 8: The shape of the stones visible via ultrasound in cattle (pea

size, single, rounded or pedunculated) (white arrow) Fig. 9: The shape of the stones visible via ultrasound in buffalo (grapes

like small sandy stones) (black arrow) Fig. 10: Narrowing of the urethra behind the site of obstruction and

widening of the lumen before the site of obstruction

DISCUSSION

Urolithiasis is an important disease throughout the world. It is more common in feeder animals but is also seen in mature breeding animals; and is often seen during winter in steers or on range during severe weather condition with limited water intake (Cartee et al. 1980, Walker and Vaughan 1980). In the present study the majority of animals presented were young (2.5-18 months). It was reported that the disease affect both sexes, but obstructive urolithiasis occurs primary in males due to the anatomical differences (Hooper and Tylor 1995, Larson 1996). Castration was thought to be a predisposing cause of the disease in male animals by removing hormonal influences necessary for mature development of the penis and urethra (Khamis and Saleh 1970, Gohar 1978, Monoghan and Boy 1990, Larson 1996). This was in contrary to the present results as all examined cases were non-castrated males, but these findings were in accordance with those observed by Misk and Semeika (2003).

Diagnosis of urolithiasis in ruminants depends mainly on a history of anurea, clinical symptoms and physical examination (Radostitis et al. 2000 and Loretti et al. 2003). Rectal palpation and urethral pulsation were usually used for differential diagnosis between

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cases of urethral obstruction with or without bladder rupture (Cartee et al., 1980, Walker and Vaughan 1980, Misk and Semeika 2003). However, in the present study rectal palpation was not available in 18 cases because the animals were too young (2.5- 9 months). However, urethral pulsation ventral to the anus was seen in cases where the urinary bladder was not ruptured.

In contrast to Misk and Semeika (2003), that found that radiography is a highly diagnostic method in cases of urethral obstruction, Tyagi and Singh (1996) stated that attempts to locate calculi by radiographic examination is not successful. In our study, radiography failed in diagnosis of urolithiasis in 8 cases (6 buffaloes and 2 cattle).

Ultrasound offers a non invasive method for diagnosis of urolithiasis, localization of the urethral calculi, as well as diagnosis of dilated urethra, cystitis, urethritis and rupture of the urethra or the urinary bladder (Braun 1993). In the contrary to radiography, ultrasound does not involve the use of ionizing radiation as in radiography. Therefore, it is safe for the patient and operator. It is not necessary to leave the room during investigation as the case with radiography and animals can be reassured and/or restrained during the examination (Cartee et al., 1980).

Braun (1993) mentioned that it is rarely necessary to anaesthetize animals for ultrasound examination. The findings of the present study match the previous suggestions because ultrasound examination was done for all cases with the animals in standing position and without sedation. Ultrasound measurements of the wall thickness of the urinary bladder and urethra has been claimed to be useful as a method of determining the increase in the wall thickness in cases of cystitis and urethritis (Braun 1993, Hoque et al., 2002). In this study ultrasound examination was helpful in measuring the thickness of the urinary bladder and urethral wall in one case of cystitis and urethritis.

In contrary to our results, rupture of the urethra due to urolithiasis was reported to be more common than rupture of the urinary bladder (Walker and Vaughan 1980, Hoque et al., 2002). In the present study, rupture of the urethra was diagnosed only in one case. The rupture of the urinary bladder is usually diagnosed by abdominocentesis (Cartee et al., 1980, Walker and Hull 1984). However, in the present study abdominocentesis was not diagnostic for the rupture of the urinary bladder as in many cases where free abdominal fluid was visible via ultrasound examination, the urinary bladder was seen to be intact. This is of importance in decision making of laparotomy as the urinary bladder

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in ruminants usually seal with fibrin or omentum in 3 to 5 days after rupture if it kept empty (Walker and Hull 1984). The site of rupture of the urinary bladder was not always visible via ultrasound, it could be determined only in four cases.

In conclusion ultrasound examination was found to be a non invasive diagnostic technique for cases of urolithiasis and rupture of the urinary bladder, as well as in diagnosis of lower urinary tract inflammatory conditions as cyctitis, and urethritis. Ultrasonography can be successfully used as an aid diagnostic technique with radiography for diagnosis of cases of urine retention due to obstructive lesions as it allows better examination of the urinary bladder and the urethra.

REFRENCES

Braun, U. (1993): Ultrasonographic examination of the left kidney, the

urinary bladder, and the urethra in cows. Zentralblatt Vet. Med.

40, (1): 1-9. Cartee, R.E.; Selcer, B.A. and Patton, C.S. (1980): Ultrasonographic

diagnosis of renal disease in small animals, J. Am. Vet. Med.

Assoc. 176, (5): 426-30. Gohar, H.M. (1978): Experimental studies on some factors leading to

formation of urinary calculi in sheep and goats Ph.D. Thesis;

Fac. Vet. Med., Cairo University. Geccelep, M. and Alkan, I. (2000): Congenital dilatation in a male

montaphon calf, Israel Vet. Med. J.; 55, (1): 243-246. Hooper, R.N. and Taylor, T.S. (1995): Urinary surgery, Vet. Clinic of

North America, Food animal practice; 11,(1): 403-409. Hoque, M.R.; Somvanshi, G.R. and Singh, 1.V. (2002): Ultrasonographic

evaluation of urinary bladder in normal, fern fed and enzootic bovine haematuria-affected cattle, J. Vet. Med. Pathol. Clin.

Med.; 49, (8): 403-407. Khamis, Y. and Saleh, M. (1970): Urolithiasis syndrome in ruminants.

Egypt Vet. Med. J. 18: 242-248. Kyles, A.E.; Hardie, E.M.; Wooden, B.G., Adin, C.A.; Stone, E.A.;

Gregory, C.R.; Mathews, K.G.; Cowgill, L.D.; Vaden, S.; Nyland, T.G. and Ling, G.V. (2005): Clinical, clinicopathologic, radiographic, and ultrasonographic abnormalities in cats with urethral calculi 163 cases (1984 2002), J. Am. Vet. Med. Assoc., 15, (6), 932-936.

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Larson, B.L. (1996): Identifying, treating, and preventing of bovine

urolithiasis. Vet. Med.; (91), 366-377 Le'veille, R. (1998): Ultrasonography of urinary bladder disorders, The

Vet. Clinics of North America, small animal practice; 28, (4):

799-802 Loretti, P.A.; de Oliveria, L.O., Cruz C.F. and Driemier, D. (2003):

Clinical and pathological study of an outbreak of obstructive urolithiasis in feedlot cattle in south Brazil, Pesq. Vet. Bras.;

23, (2): 233-236 Lotfia, S.F.; Khamis, Y.; Hegazy, A.A.; Gohar, H. M. and Shamaa, A.A.

(1999): Effect of high dietary levels of calcium, phosphorus and magnesium on urolithiasis in sheep. J. of Egyptian Vet.

Med. Assoc.; 59: 213-218 Misk, N.A. and Semieka, M.A. (2003): Clinical studies on obstructive

urolithiasis in male cattle and buffaloes, Assiut Vet. Med. J.;

49, (97): 258-274 Monoghan, M.L. and Boy, M.G. (1990): Ruminant renal system, In

Large Animal Internal Medicine. St. Louis, CV Mosby; 888

890. Palmer, J.L.; Dykes, N.L., Love, K. and Fubini, S.L. (1998): Contrast

radiography of the lower urinary tract in the management of obstructive urolithiasis in small ruminants and swine. Vet.

Radiol. Ultrasound; 39, (3): 175-180. Payne, J.M. (1989): Metabolic and nutritional diseases in cattle.

Blackwell, Oxford; 41-44 Radostitis, O.M.; Blood, D.C.; Gay, C.C. and Hinchey, K.W. (2000):

Veterinary Medicine a textbook of the diseases of cattle, sheep,

pig, goat and horse. Bailliere Tindall, London, 1877 Tantawy, M. (1985): A urethral calculus in a steer. Assiut Vet. Med. J.;

14, (27): 203-206 Tyagi, R.P. and Singh, J. (1996): Ruminant surgery. A textbook of

surgical diseases of Cattle, Buffaloes, Camel, Sheep and Goat.

CBS Publishers and Distributors, 263-271 Walker, D.F. and Vaughan, J.T. (1980): Bovine and equine urogenital

surgery; 59-66 Philadelphia, Lea& Febiger) Walker, D.F. and Hull, B.L. (1984): Urinary system surgery. In:

Jennings PB (eds): The practice of large animal surgery; Vol. 2, 1072-1080, Philadelphia, W.B. Saunders Co.

268

REFRENCES
Braun, U. (1993): Ultrasonographic examination of the left kidney, the
urinary bladder, and the urethra in cows. Zentralblatt Vet. Med.
40, (1): 1-9. Cartee, R.E.; Selcer, B.A. and Patton, C.S. (1980): Ultrasonographic
diagnosis of renal disease in small animals, J. Am. Vet. Med.
Assoc. 176, (5): 426-30. Gohar, H.M. (1978): Experimental studies on some factors leading to
formation of urinary calculi in sheep and goats Ph.D. Thesis;
Fac. Vet. Med., Cairo University. Geccelep, M. and Alkan, I. (2000): Congenital dilatation in a male
montaphon calf, Israel Vet. Med. J.; 55, (1): 243-246. Hooper, R.N. and Taylor, T.S. (1995): Urinary surgery, Vet. Clinic of
North America, Food animal practice; 11,(1): 403-409. Hoque, M.R.; Somvanshi, G.R. and Singh, 1.V. (2002): Ultrasonographic
evaluation of urinary bladder in normal, fern fed and enzootic bovine haematuria-affected cattle, J. Vet. Med. Pathol. Clin.
Med.; 49, (8): 403-407. Khamis, Y. and Saleh, M. (1970): Urolithiasis syndrome in ruminants.
Egypt Vet. Med. J. 18: 242-248. Kyles, A.E.; Hardie, E.M.; Wooden, B.G., Adin, C.A.; Stone, E.A.;
Gregory, C.R.; Mathews, K.G.; Cowgill, L.D.; Vaden, S.; Nyland, T.G. and Ling, G.V. (2005): Clinical, clinicopathologic, radiographic, and ultrasonographic abnormalities in cats with urethral calculi 163 cases (1984 2002), J. Am. Vet. Med. Assoc., 15, (6), 932-936.
267
Assiut Vet. Med. J. Vol. 52 No. 110 July 2006
Larson, B.L. (1996): Identifying, treating, and preventing of bovine
urolithiasis. Vet. Med.; (91), 366-377 Le'veille, R. (1998): Ultrasonography of urinary bladder disorders, The
Vet. Clinics of North America, small animal practice; 28, (4):
799-802 Loretti, P.A.; de Oliveria, L.O., Cruz C.F. and Driemier, D. (2003):
Clinical and pathological study of an outbreak of obstructive urolithiasis in feedlot cattle in south Brazil, Pesq. Vet. Bras.;
23, (2): 233-236 Lotfia, S.F.; Khamis, Y.; Hegazy, A.A.; Gohar, H. M. and Shamaa, A.A.
(1999): Effect of high dietary levels of calcium, phosphorus and magnesium on urolithiasis in sheep. J. of Egyptian Vet.
Med. Assoc.; 59: 213-218 Misk, N.A. and Semieka, M.A. (2003): Clinical studies on obstructive
urolithiasis in male cattle and buffaloes, Assiut Vet. Med. J.;
49, (97): 258-274 Monoghan, M.L. and Boy, M.G. (1990): Ruminant renal system, In
Large Animal Internal Medicine. St. Louis, CV Mosby; 888
890. Palmer, J.L.; Dykes, N.L., Love, K. and Fubini, S.L. (1998): Contrast
radiography of the lower urinary tract in the management of obstructive urolithiasis in small ruminants and swine. Vet.
Radiol. Ultrasound; 39, (3): 175-180. Payne, J.M. (1989): Metabolic and nutritional diseases in cattle.
Blackwell, Oxford; 41-44 Radostitis, O.M.; Blood, D.C.; Gay, C.C. and Hinchey, K.W. (2000):
Veterinary Medicine a textbook of the diseases of cattle, sheep,
pig, goat and horse. Bailliere Tindall, London, 1877 Tantawy, M. (1985): A urethral calculus in a steer. Assiut Vet. Med. J.;
14, (27): 203-206 Tyagi, R.P. and Singh, J. (1996): Ruminant surgery. A textbook of
surgical diseases of Cattle, Buffaloes, Camel, Sheep and Goat.
CBS Publishers and Distributors, 263-271 Walker, D.F. and Vaughan, J.T. (1980): Bovine and equine urogenital
surgery; 59-66 Philadelphia, Lea& Febiger) Walker, D.F. and Hull, B.L. (1984): Urinary system surgery. In:
Jennings PB (eds): The practice of large animal surgery; Vol. 2, 1072-1080, Philadelphia, W.B. Saunders Co.