A survey of congenital reproductive abnormalities in rams in abattoirs in South west England.

Congenital abnormalities of the reproductive tract of male sheep were surveyed at three abattoirs in the south west of England during the period June 2000-January 2004. A total of 7307 rams were examined [6521 lambs (prepubescent) and hoggets (aged from their first autumn after birth until first shorn) and 786 adult rams mature rams that had been exposed to ewes]. A total of 156 congenital lesions were detected, 87 of which occurred in lambs. Testicular hypoplasia was the most common lesion occurring in 69 lambs as well as eight hoggets ('microtestes' were recognized in nine other animals in which the testis was disproportionately smaller than the epididymis). The second most common lesion found was notched scrotum occurring in 34 animals (27 young rams and seven adults). Some cases of notched scrotum were accompanied by hypospadias which was seen in a total of seven lambs and eight hoggets. Other lesions, detected in five or less animals (less than approximately 0.05% of the animals examined), included cryptorchidism and various abnormalities of the epididymis (segmental aplasia of the epididymis, blind efferent ducts and epididymal cyst) and congenital scrotal hernia. The overall prevalence of congenital lesions of 2.21% emphasizes the importance of undertaking breeding soundness examinations of young rams before they are put with the flock.

Reliability of radiological assessment of ulnar trochlear notch sclerosis in dysplastic canine elbows.

OBJECTIVES: The objectives of this study were to quantify the sensitivity and specificity of visual assessment of radiographs of the canine elbow in detecting ulnar trochlear notch sclerosis, to establish interobserver and intra-observer variation for the presence and grade of sclerosis and to quantify the effect of radiographic exposure on observer grading. METHODS: Mediolateral elbow radiographs were obtained from Labrador retrievers (n=34) aged between six and 18 months. Radiographs from dogs with an arthroscopic diagnosis of fragmented medial coronoid process (n=17) and those from a control population (n=17) were subjected to observer grading for the presence or absence of and the grade of ulnar trochlear notch sclerosis. Interobserver and intra-observer variation and observer sensitivity and specificity were calculated. Digital data from the ulnar trochlear notch were correlated with mean observer grade to quantify the effect of radiographic exposure on observer grade. RESULTS: Interobserver agreement was "fair" (kappa=0.251 to 0.369) and intra-observer agreement was "moderate" to "substantial" (kappa=0.462 to 0.667). The sensitivity of observer assessment was 72 per cent with a specificity of 22 per cent. Mean observer grade was not significantly correlated with the degree of radiographic exposure (P=0.70). CLINICAL SIGNIFICANCE: Ulnar trochlear notch sclerosis is a phenomenon associated with fragmented medial coronoid process. However, interobserver agreement in grading this feature is only fair, being identified by observers with moderate sensitivity but with relatively poor specificity. This low specificity may predispose to overdiagnosis in clinical cases. Intra-observer agreement is moderate to substantial, suggesting that individuals can reliably quantify this radiological feature on multiple occasions. The ability of observers to assess the degree of sclerotic change is not significantly affected by radiographic exposure.

Estimation of the volume of the gall bladder of 32 dogs from linear ultrasonographic measurements.

The maximum length and depth of the longitudinal section, and the maximum width and depth of the transverse section of the gall bladders of 32 dog cadavers were measured ultrasonographically; the contents of the gall bladder were then aspirated and its actual volume measured. The volume of the gall bladder was estimated from the ultrasonographic measurements by using formulae suggested for assessment of the volumes of the urinary bladder in human beings and the gall bladder of dogs, and these formulae were compared with a formula derived from the measurements made in this study. In 21 of the dogs, the measurements were repeated twice so that their reproducibility could be evaluated. All the formulae gave good estimations of the volume of the dogs' gall bladders, but the formula for the human urinary bladder volume was better than the other two. The actual volume of the gall bladder was related to the dogs' bodyweight. There were no significant differences between the repeated measurements of the maximum length and depth of the longitudinal section or the width of the transverse section of the gall bladder, but there were significant variations in the depth of the transverse section.

Bacterial cholangitis/cholangiohepatitis with or without concurrent cholecystitis in four dogs.

OBJECTIVES: To evaluate the clinical, clinical pathology, diagnostic imaging, microbiological and pathological features of cholangitis/cholangiohepatitis in the dog. METHODS: The study design was a retrospective review of cases of bacterial cholangitis/cholangiohepatitis presented to the University of Bristol during the period 1995 to 2000. The diagnosis was made based on hepatic histopathological findings and positive bile culture results. RESULTS: Four dogs met the inclusion criteria. Common presenting signs included anorexia (n=4), jaundice (n=4), vomiting (n=4) and pyrexia (n=2). All four dogs had a leucocytosis or neutrophilia reported at some time in their history along with serum bilirubin elevation. In addition, serum alkaline phosphatase and alanine transaminase activity was increased in all of the dogs in which it was measured both before and at the time of referral. In general, the diagnostic imaging findings were non-specific. Organisms cultured from bile aspirates were Escherichia coli (n=3), Clostridium species (n=2) and a faecal Streptococcus species (n=1). Two cases resolved with medical treatment alone; two with concurrent cholecystitis required cholecystectomy. Following surgery, both of these cases showed a resolution of clinical signs. CLINICAL SIGNIFICANCE: This report highlights the fact that bacterial cholangitis/cholangiohepatitis with or without concurrent cholecystitis should be considered as a potential differential in dogs presenting with signs referable to biliary tract disease.

A technique for pelvic radiography in the standing horse.

REASONS FOR PERFORMING STUDY: An alternative technique of radiographing the pelvis in the standing horse is required, to avoid the risks associated with general anaesthesia. HYPOTHESIS: That lateral oblique radiography in the standing horse would be a useful technique in the investigation of pelvic injury. OBJECTIVES: To describe the technique of lateral oblique pelvic radiography in the standing horse and demonstrate the feasibility and usefulness of this technique. METHODS: A technique for lateral oblique radiography in the standing horse was devised and retrospective review made of radiographic findings in 18 clinical cases. RESULTS: The caudal iliac shaft, greater trochanter of the femur, femoral head, acetabulum and coxofemoral articulation on the side under investigation were visualised consistently using this technique. Of the 18 cases, 3 iliac shaft fractures, 1 acetabular fracture, 2 coxofemoral luxations and 4 horses with new bone formation around the coxofemoral joint and/or proximal femur were identified. CONCLUSIONS: Lateral oblique radiography in the standing, conscious horse can be used to investigate conditions affecting the caudal iliac shaft, coxofemoral articulation and proximal femur in the horse. POTENTIAL RELEVANCE: The technique is straightforward, noninvasive and useful in the investigation of horses with suspected pelvic injury. However, not all pelvic injuries would be identified, and normal radiographic findings do not rule out injury or fractures elsewhere in the pelvis.

Ultrasonographic evaluation of the thickness of the small intestinal wall in dogs with inflammatory bowel disease.

OBJECTIVES: To establish whether the intestinal wall thickness, as measured ultrasonographically, is significantly increased in dogs with inflammatory bowel disease (IBD). The results would provide the information necessary to decide whether measurement of ultrasonographic wall thickness can predict IBD in dogs. METHODS: The intestinal wall thickness of 75 dogs with idiopathic IBD, as measured by ultrasonography, was compared with recently published normal values. IBD was either confirmed histologically (n = 54) or suspected (n = 21). In all cases there was a positive response to immunosuppressive treatment. RESULTS: A positive association between intestinal wall thickness in dogs and either the histological diagnosis or the response to treatment was not found. Ultrasonographic intestinal wall measurements do not appear to be able to establish a diagnosis of intestinal inflammation and may result in a false negative diagnosis in cases of IBD. CLINICAL SIGNIFICANCE: The same 'grey zone' of between 4 and 6 mm used in humans can be used in the canine duodenum to distinguish the normal range, reserving the term 'abnormal' for an intestinal measurement greater than 6 mm in the duodenum and greater than 4.7 mm in the jejunum.

Ultrasonography of the medial palmar intercarpal ligament in the Thoroughbred: technique and normal appearance.

REASONS FOR PERFORMING STUDY: Tearing of the medial palmar intercarpal ligament (MPICL) has been recognised as a cause of lameness in the Thoroughbred, but diagnosis is difficult due to the nonspecific clinical signs, and can be achieved only by performing arthroscopy on the mid carpal joint (MCJ). It would be beneficial to be able to image the MPICL using ultrasonography to determine whether pathology is present in the ligament in order to aid diagnosis and prognosis. OBJECTIVES: To determine whether the MPICL could be imaged using ultrasound from the dorsal aspect of the MCJ, and to describe the technique and normal ultrasonographic appearance of the ligament. METHODS: A pilot study was performed using 2 cadaver carpi. Each carpus in turn had the MPICL imaged simultaneously using arthroscopy and ultrasound, with a metallic probe positioned on the dorsal aspect of the ligament to highlight the position of the MPICL. Six further pairs of carpi had the MPICL imaged ultrasonographically followed by dissection of the carpus to evaluate the ligament and relate its anatomy to the ultrasound images. Finally, 15 Thoroughbreds with no history of lameness isolated to the carpus had their MPICLs assessed and measured ultrasonographically. RESULTS: The MPICL could be imaged via the dorsal aspect of the MCJ using standard ultrasound equipment. The body and division into medial and lateral branches could be seen as a distinct, moderately dense granular echogenic structure in the palmar aspect of the joint, with clearly defined margins. CONCLUSIONS: The normal MPICL can be imaged reliably using ultrasound in the Thoroughbred from the dorsal aspect of the MCJ. There is a wide range in the normal width of the lateral aspect of the MPICL, but there is good symmetry between contralateral limbs. POTENTIAL RELEVANCE: This report of the normal ultrasonographic appearance of the ligament will be beneficial in acting as a reference for the detection of pathology using ultrasound.

Radiographic progression of osteoarthritis of the canine stifle joint: a prospective study.

A radiographic scoring system for features of osteoarthritis of the canine stifle joint was devised. Intra- and inter-rater agreement was assessed by calculation of unweighted kappa statistics. "Global score," "effusion," "osteophytosis," and "intra-articular mineralization" were all features that had acceptable reliability, but "subchondral sclerosis" did not. The scoring system was used in a 13-month prospective study of the radiographic progression of osteoarthritis of the stifle joint, secondary to cranial cruciate ligament deficiency, in 58 dogs. In the index stifle joints all features were characterized by significant change over time, but osteophytosis had the greatest degree of change. In addition, 40% of contralateral joints showed progressive osteophytosis.

Thoracic high-resolution computed tomography in the diagnosis of metastatic carcinoma.

Three dogs were presented for investigation of recurrent pyrexia of unknown origin, chronic vomiting and respiratory distress, respectively. One dog was markedly underweight and the other two were cachexic. Physical examination and initial diagnostic tests failed to establish the underlying cause of the presenting signs. Thoracic radiographs were within normal limits for the age of the dog. In each case there was a high index of suspicion for an occult neoplastic process in view of the profound unexplained weight loss present. High-resolution computed tomography (HRCT) of the thorax was performed. The lung fields were divided into three zones for analysis and a novel classification scheme was used to describe the HRCT findings in each zone. Postmortem examination and histopathology confirmed the presence of an infiltrating metastatic carcinoma in all three cases. The HRCT changes correlated closely with the pathological findings. The authors conclude that HRCT of the lung should be considered for pulmonary metastatic screening in the dog and introduce a classification system for HRCT findings, based on terminology used in human medicine.

Prevalence of polycystic kidney disease in Persian cats in the United Kingdom.

The prevalence of polycystic kidney disease was assessed in 132 Persian cats, 46 of them referred for the investigation and treatment of medical or surgical conditions, and 86 apparently healthy cats referred specifically to be screened for the disease. Cats referred for the investigation of renomegaly or renal failure were excluded, and cats under 10 months old were only included if they had been examined postmortem. One hundred and twenty-six of the cats were examined ultrasonographically with a 7.5 MHz sector scanner, and the other six cats were examined postmortem. Forty-nine of the 86 cats referred specifically for screening (57.0 per cent) and 16 of the 46 cats referred for other clinical reasons (34.8 per cent) were affected by the disease, giving an overall prevalence of 49.2 per cent.

Targeted lymph node immunization can protect cats from a mucosal challenge with feline immunodeficiency virus.

With the rapid spread of human immunodeficiency virus (HIV) infection worldwide it is clear that effective strategies for mucosal vaccination against lentiviruses are urgently required. The aim of the present study is to determine whether protective immune responses against a mucosal challenge by feline immunodeficiency virus (FIV) can be elicited by targeting the immunization to the medial iliac lymph nodes--the principal site of migration of cells from the genital and rectal mucosa. Cats were challenged with homologous FIV via the rectal route. Targeted lymph node immunization was found to be an effective route of immunization eliciting both humoral and proliferative responses to peptide-based and fixed cell vaccines. Vaccination with fixed virus infected cells elicited protection against a cell-free mucosal FIV challenge. In addition, some cats vaccinated with fixed uninfected cells also remained uninfected following a cell-associated FIV challenge.

The role of ultrasound in the assessment of laryngeal paralysis in the dog.

Forty dogs with clinical signs suggestive of upper respiratory tract disease underwent echolaryngography and laryngoscopy. Laryngoscopy was used as the definitive technique to diagnose laryngeal paralysis. The ultrasound investigation accurately indicated the presence of the paralysis and confirmed the uni- or bilateral nature of the disorder. Findings indicative of laryngeal paralysis included asymmetry or absence of motion of the cuneiform processes (30/30), abnormal arytenoid movement (16/30), paradoxical movement (9/30), caudal displacement of the larynx (2/30) and laryngeal collapse (1/30). Thirty dogs were found to be afflicted with laryngeal paralysis and ten had normal laryngeal motility.

Ultrasonographic appearance of the superficial supramammary lymph nodes in lactating dairy cattle.

The superficial supramammary lymph nodes of 54 lactating dairy cows were examined ultrasonographically with a 7.5 MHz linear transducer; each node was measured in two planes within 24 hours of recording the milk somatic cell count. In most cows, the nodes were well demarcated from the surrounding tissue. The parenchyma of the nodes ranged from hypoechoic to anechoic, with a central bright hyperechoic area, and a thin hyperechoic line surrounded the nodes. The size of the nodes varied, but their internal architecture remained relatively consistent. Their mean length was 7.4 cm (range 3.5 to 15 cm) and their mean depth was 2.5 cm (range 1.2 to 5.7 cm). They were significantly larger in cows with more lactations (P<0.05), but there were no correlations between their size and either the time calved or the milk somatic cell count. The lymph nodes on sides which were positive in a California milk test were significantly larger than those on sides which were negative (P<0.05).

Dysuria resulting from an encapsulated haematoma in a recently spayed bitch.

A 15-month-old bitch was presented for investigation of a two-month history of dysuria. Clinical signs had developed within one day of routine ovariohysterectomy. A rounded mass was palpable in the caudal abdomen which was shown radiographically to displace and compress the urinary bladder. On ultrasonography, the mass was composed primarily of pockets of hypoechoic fluid divided by hyperechoic septae; blood was obtained on fine-needle aspiration. The mass was surgically removed and the dog regained normal urinary function within a few days. Histopathological examination showed the mass to be an encapsulated haematoma, which is likely to have developed as a result of the ovariohysterectomy.

Anatomical, cytogenetic and behavioural studies of freemartin ewes.

The external phenotype and reproductive behaviour of 21 freemartin sheep and two male pseudohermaphrodite sheep were recorded with the aim of identifying any characteristics which might be used to predict a failure to breed. The size and shape of the vulva and clitoris, the length of the vagina, the size of the teats, the presence or absence of inguinal gonads, and the ultrasonographic characteristics of the inguinal gonads were recorded. A subjective assessment of the masculinity of each animal's body form was also made, and its behavioural responses to a virile ram and to an oestrus ewe were recorded. A number of physical and behavioural abnormalities were detected but the only consistent finding in all 23 animals was a short vagina which varied in length from 3.1 to 7.0 cm, compared with 10 to 14 cm in normal animals.

Frequency of urination and ultrasonographic estimation of residual urine in normal and dysuric dogs.

The aim of this study was to determine residual urine and frequency of urination in normal male and female dogs and to compare these with dogs with neurogenic and obstructive dysuria. The bladder volume before urination was estimated ultrasonographically in 99 dogs (48 normal and 51 abnormal dogs). Each animal was then taken outdoors and walked on grass for 10 minutes. The number of attempts to urinate (successful or not) was recorded. Bladder urine volume after urination was then calculated. Normal females made only one or two (100 per cent successful) attempts to urinate while males a mean of 6.9 attempts (mean 75.4 per cent successful) within 10 minutes. The residual urine per kg body weight of normal dogs varied from 0.1 to 3.4 ml kg(-1)(median 0.2 ml kg(-1)). The residual urine volumes of normal dogs were significantly less (P<0.0001) than those of dogs with neurological disorders or obstructive disease. Ultrasonographic estimation of residual urine volumes could be valuable in diagnosing suspected neurological or obstructive bladder disease and in monitoring the response to treatment.

Comparison of ultrasonographic and radiographic measurements of canine prostate dimensions.

The purposes of this study were to: 1) compare prostatic dimensions measured on radiographic and ultrasonographic images and 2) compare a subjective radiographic assessment of prostate size with a previously-described objective method. Thirty-four male dogs undergoing investigation of prostatic disorders were used. Prostate length and depth were measured from ultrasonographic and radiographic images. A subjective assessment of prostate size ('small', 'normal', or 'enlarged') was made in 29 animals by one of the authors who was unaware of radiographic or ultrasonographic measurements. In addition, the distance from sacral promontory to the pubic brim was also measured. A prostate length or depth of >70% of this distance was defined as 'enlarged' and <70% as 'normal'. After the effects of magnification on radiographic measurements were eliminated, there were no significant differences between prostatic length measured by the two methods. However, a significant difference was obtained between prostatic depth measurements. The subjective assessment agreed with a previously described objective assessment of prostatic size in 21/29 dogs for prostate length but in only 12/29 for depth. Prostatic length varied from 46.6 to 116.4% (mean 75.7%) of the distance from the pubic brim to the sacral promontory. Prostatic depth varied from 33.0% to 94.6% (mean 59.7%) of the same distance. It is recommended that prostate length, rather than depth, be used when evaluating prostate size from lateral abdominal radiographs.