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Lead (Pb) is a worldwide environmental contaminant known to adversely affect multiple organ systems in both mammalian and avian species. In birds, a common route of exposure is via oral ingestion of lead particles. Data are currently lacking for the retention and clearance of Pb bullet fragments in gastrointestinal (GI) tract of birds while linking toxicity with blood Pb levels. In the present study, northern bobwhite quail fed a seed-based diet were orally gavaged with Pb bullet fragments (zero, one or five fragments/bird) and evaluated for rate of fragment clearance, and changes in peripheral blood, renal, immune, and gastrointestinal parameters. Based on radiographs, the majority of the birds cleared or absorbed the fragments by seven days, with the exception of one five-fragment bird which took between 7 and 14 days. Blood Pb levels were higher in males than females, which may be related to egg production in females. In males but not females, feed consumption, body weight gain, packed cell volume (PCV), plasma protein concentration, and δ-aminolevulinic acid dehydratase (δ-ALAD) activity were all adversely affected by five Pb fragments. Birds of both sexes that received a single Pb fragment displayed depressed δ-ALAD, suggesting altered hematologic function, while all birds dosed with five bullet fragments exhibited greater morbidity.

Birds are exposed to Pb by oral ingestion of spent Pb shot as grit. A paucity of data exists for retention and clearance of these particles in the bird gastrointestinal tract. In the current study, northern bobwhite quail (Colinus virginianus) were orally gavaged with 1, 5, or 10 Pb shot pellets, of 2-mm diameter, and radiographically followed over time. Blood Pb levels and other measures of toxicity were collected, to correlate with pellet retention. Quail dosed with either 5 or 10 pellets exhibited morbidity between weeks 1 and 2 and were removed from further study. Most of the Pb pellets were absorbed or excreted within 14 d of gavage, independent of dose. Pellet size in the ventriculus decreased over time in radiographs, suggesting dissolution caused by the acidic pH. Birds dosed with one pellet showed mean blood Pb levels that exceeded 1,300 µg/dl at week 1, further supporting dissolution in the gastrointestinal tract. Limited signs of toxicity were seen in the one-pellet birds; however, plasma δ-aminolevulinic acid dehydratase (d-ALAD) activity was persistently depressed, suggesting possible impaired hematological function., (© 2010 SETAC.)

A 10-month-old, neutered male Saint Bernard presented for evaluation of acute, severe vomiting. A soft-tissue mass was noted within the stomach on survey abdominal radiographs. The diagnosis of pylorogastric intussusception was made during exploratory celiotomy. The intussusception was manually reduced at surgery, the pyloric antrum was enlarged, and the duodenum was permanently affixed to the abdominal wall in an attempt to prevent recurrence of the intussusception. The dog recovered, has gained weight (5 kg), and has had only one isolated episode of vomiting during the one year since discharge from the hospital. This report documents the fourth reported case of pylorogastric (i.e., duodenogastric, gastrogastric) intussusception in the veterinary literature and is the first report that details the surgical management of the disease.

Objective: To identify correlations between ultrasonographic findings and specific hepatic diseases in cats., Design: Retrospective study., Sample Population: Medical records of 72 cats with a histopathologic diagnosis of hepatic disease and diagnostic-quality abdominal ultrasonograms between 1985 and 1997., Procedure: Abdominal ultrasonographic findings in 72 cats with histologically confirmed hepatic disease (hepatic lipidosis excluded) were reviewed. Rather than attempt to combine individual ultrasonographic findings with specific hepatic diseases, 2 classification trees were created as models to correlate certain groups of abnormalities with specific hepatic diseases or with malignant and benign lesions of the liver. Sensitivity and specificity of classification trees were calculated., Results: Use of a classification tree resulted in correct classification of malignant versus benign hepatic lesions in 88.9% of cats that had hepatic disease (sensitivity, 90.7%; specificity, 86.1%). Use of a classification tree to distinguish individual types of hepatic diseases resulted in mostly accurate classification of hepatic lymphosarcoma (sensitivity, 70.5%; specificity, 98.2%), cholangitis-cholangiohepatitis syndrome (sensitivity, 87%; specificity, 90%), and benign lesions of the liver (sensitivity, 84.6%; specificity, 86.4%). Criteria that helped most in differentiating among various hepatic diseases were abnormalities within other organs (spleen, lymph nodes) and appearance of the hepatic portal system. A correlation was not found between focal or multifocal appearance of hepatic lesions and specific hepatic diseases., Clinical Implications: Use of classification trees to distinguish among specific hepatic diseases or between malignant and benign hepatic lesions provides potentially useful algorithms for ultrasonographic evaluation of cats with hepatic disease.

A 4-year-old Rhodesian Ridgeback had acute onset of vomiting, lethargy, and discolored urine. Physical examination revealed lethargy, pyrexia, weak femoral pulses, cardiac arrhythmia, distended abdomen, and signs of pain on abdominal palpation. Abdominal radiography and ultrasonography revealed a gas-containing lesion in the cranial portion of the abdomen. Preoperative care included administration of fluids, antibiotics, and antiarrhythmic medication. Exploratory laparotomy revealed hemobilia and a 360 degrees clockwise torsion of the papillary process of the caudate lobe of the liver. Clinical signs resolved completely after liver lobectomy, and the dog was alive 2 years after surgery. Torsion of a liver lobe is rare in dogs. Necrosis of the involved liver lobe can result in acute weakness, shock, and death. Hemodynamic stabilization, antibiotic treatment, and surgical intervention have been successful in treating this condition. Liver lobe torsion should be considered on the differential diagnoses list of acute abdominal pain.

A left-lateralized, lumbosacral intervertebral disk herniation, which was not apparent on epidurography, was diagnosed in a dog with magnetic resonance imaging. Precise, preoperative localization and characterization of the lesion allowed surgical approach and excision with minimum disruption of surrounding tissues.

Hepatobiliary scintigraphy (HBS) was performed in 10 cats with histologically documented hepatobiliary disease. The scintigraphic patterns were classified into one of 5 categories: normal, primary hepatocellular dysfunction, primary intrahepatic cholestasis, mixed hepatocellular and intrahepatic cholestasis, and extrahepatic obstructive patterns. Initial attempts were made to correlate specific disease entities with HBS patterns, but a consistent relationship could not be determined. A correlation between the histological severity of a given hepatic disease and the HBS pattern was made. All cats (n = 5) with a mixed hepatocellular and intrahepatic cholestasis scintigraphic pattern with normal gallbladder function had a histologically severe form of their individual hepatic disease. Three of the 4 cats with an intrahepatic cholestasis pattern and normal hepatocellular and gallbladder function had histologically mild or moderate forms of their individual hepatic diseases. One cat had an extrahepatic obstructive pattern where no radiopharmaceutical was identified in the gallbladder or small intestine by 3 hours postinjection. This study suggests that HBS can be useful in cats with hepatobiliary disease to assess the severity of hepatic dysfunction, and to determine if extrahepatic biliary obstruction is present. Correlation between HBS patterns and specific disease entities such as hepatic lipidosis or cholangitis-cholangiohepatitis syndrome could not be made in this study.

Two dogs were found to have intraluminal gallbladder masses which caused partial or complete extrahepatic biliary obstruction. On histological examination, the gallbladder masses were confirmed to be mucoceles. Gallbladder mucoceles are rare in humans and previously have been described only after gallbladder rupture in two dogs. In the dogs of this report, the biliary obstruction was relieved by cholecystectomy. Each dog also had histological evidence of chronic liver disease with intrahepatic cholestasis. The clinical diagnosis of biliary obstruction was based on scintigraphic and sonographic findings which will be discussed and compared with other hepatobiliary diseases.

The umbilical stalk, vein, and arteries, urachal region, and urinary bladder of 9 healthy Holstein calves were scanned ultrasonographically at weekly intervals from 1 day to 3 weeks of age. Four additional calves of representative ages, 1 day, 1 week, 2 weeks, and 3 weeks were euthanatized after ultrasonographic evaluation of the umbilical structures. Umbilical structures from these 4 calves were dissected, photographed, and examined histologically to ensure normalcy. These gross specimens were correlated with the ultrasonographic images and compared with serial ultrasonograms of 9 calves. The ultrasonographic scanning technique and the appearance of normal umbilical stalk, arteries, and vein, and urachus in calves were different from those described for foals. The umbilical vein of calves was scanned from the umbilical stalk to the liver along the right abdominal wall. Two veins, which merged within the body wall, were identified within the stalk. Umbilical arteries were not found within the umbilical stalk; they ended abruptly near the apex of the urinary bladder. A urachal remnant was not identified in any of the calves. A range of normal values for measurement of the umbilical stalk, umbilical arteries, and umbilical vein at 3 sites was determined. The described ultrasonographic appearance and measurements of the normal Holstein calf umbilicus may be used as a reference for evaluation of calves with internal umbilical abnormalities.

Hepatobiliary scintigraphy provides a noninvasive assessment of hepatobiliary structure and function, and has been used extensively in people. Hepatocellular measurements determined in the cats of this study include cardiac washout (< or = 2 minutes) and time of maximal hepatic activity (< or = 5 minutes) and hepatic washout (< or = 30 minutes). The gallbladder response to synthetic cholecystokinin was determined to be < or = 3 minutes. Additional measurements also were identified. Potential use of hepatobiliary scintigraphy in feline medicine is discussed.

Pyelonephritis was experimentally induced in 10 clinically normal dogs by nephropyelocentesis and introduction of Proteus mirabilis into the randomly chosen right or left renal pelvis. Dogs were examined by nephrosonography and excretory urography before and 2 weeks after infection. The major nephrosonographic findings of pyelonephritis were renal pelvic dilatation, usually with proximal ureteral dilatation, and a hyperechoic mucosal margin line within the renal pelvis, proximal portion of the ureter, or both. In addition, at least one or more of the following were observed: generalized hyperechoic renal cortex, focal hyperechoic areas within the medulla, and focal hyperechoic or hypoechoic cortical lesions. Interpretation of excretory urograms resulted in 3 false-negative and 1 false-positive conclusions, compared with the histologic findings. Interpretation of nephrosonograms resulted in 2 false-negative and no false-positive conclusions. Of the kidneys with histologic evidence of pyelonephritis, 73% were detected by excretory urography, whereas 82% were detected by nephrosonography. Nephrosonography appeared to be useful for detection of mild to moderate cases of acute pyelonephritis that may be be interpreted as such by excretory urography.

To summarize the points discussed in this article, Small animal myelography can be performed competently and safely without specialized equipment. The newer myelographic contrast media (iohexol, iopamidol) have less neurotoxic potential than those media previously used. Myelography is necessary for the diagnosis of many neurologic disorders in small animals. Metrizamide is no longer recommended for myelography in dogs and cats. Iohexol (Isovue) in concentration of 180 mg I/mL to 300 mg I/mL is recommended for small animal myelography. Some patients with serious spinal cord disease can exhibit normal myelograms. Recognizing abnormal myelographic patterns is the hallmark of myelographic interpretation. Anticonvulsive drugs (diazepam, pentobarbital, and phenobarbital) should be available for therapy of postmyelographic seizures. Epidurography is an effective diagnostic technique in the evaluation of canine lumbosacral compressive disease. Abnormalities identified with epidurography correlate well with surgically confirmed lesions.

Osteochondritis dissecans of the proximal aspect of the medial trochlear ridge of the talus was found to be causing lameness and tarsocrural joint effusion in a male Limousin calf. Arthroscopy via a dorsolateral approach was unsuccessful in revealing the lesion in this calf. A caudomedial arthrotomy or medial malleolar osteotomy, which can be used to gain access to lesions of the medial trochlear ridge in dogs, was not attempted. The lameness gradually worsened, and the calf was slaughtered.

A urethral filling defect in the proximal portion of the pelvic urethra, suggestive of a mass, was detected by positive-contrast retrograde urethrography in 2 dogs with prostatic disease and Sertoli cell neoplasms. Extension of prostatic neoplasia into the urethra or primary urethral neoplasia were considered as explanations for the radiographic finding of an intraluminal filling defect in the pelvic urethra. Masses were visualized and biopsied during prostatic surgery. Masses were nonneoplastic and represented enlargement of the colliculus seminalis.

Transrectal ultrasonography was performed on the cranial mesenteric artery and its major branches in 23 conscious adult horses. Ultrasonographically, 25 arterial segments were classified as either normal or abnormal. These ultrasonographic classifications were later compared with the gross and histologic evaluations of each artery following necropsy of each horse. In this study, transrectal ultrasonography as a diagnostic test for verminous arteritis had a 90% sensitivity for detecting normal arteries and an 86% specificity for detecting abnormal arteries, suggesting that ultrasonography may be useful in the antemortem diagnosis of verminous arteritis.

The treatment of 62 dogs with blastomycosis was reviewed to identify prognostic factors and response to various treatment regimens. Severity of lung involvement, as determined by radiography, and the number of nonsegmented neutrophils were useful prognostic factors. Females survived treatment better than did males, but females were more prone to relapse. Ketoconazole treatment at a dose of 10 mg/kg daily for 60 days was not as effective as amphotericin B. The most notable adverse effect of amphotericin B treatment was nephrotoxicosis . Treatment with amphotericin B followed by ketoconazole was as effective as amphotericin B alone and resulted in less nephrotoxicosis . Most dogs that had relapses were retreated effectively with amphotericin B and/or ketoconazole. Canine blastomycosis was shown to be a treatable disease, with a cure rate of approximately 75%.

Real-time ultrasonography was found to be useful in the diagnosis of hydronephrosis, renal calculi, and renal neoplasia in the dog and cat. One dog with hydronephorsis, one with renal calculi, and a cat with a renal neoplasm were scanned with a real-time ultrasonic scanner. Abnormal enlargement due to fluid accumulation was determined by ultrasonographic imaging in the case of hydronephrosis. The location and mobility of the renal calculus were observed during ultrasonography. An uneven contour and parenchymal masses in the neoplastic kidney were detected by ultrasonographic imaging of the cat. The findings were confirmed either by radiography or by postmortem examination. Previously, hydronephrosis could be diagnosed only by radiography, especially by excretory urography. Ultrasonography offers a noninvasive method for diagnosis of hydronephrosis. Localization of a urinary calculus at either the proximal end of the ureter or within the renal pelvis may be difficult by radiography. The ability of real-time ultrasonography to detect motion of the calculi within the pelvis offers an improved diagnostic capability to the veterinarian. The inability of radiography to determine the cause of renal enlargement is contrasted with the ability of ultrasonography to detect changes in tissue density that might be compatible with renal neoplasms

Transrectal ultrasonography was successfully used to image the cranial mesenteric artery and its branches in 23 adult horses. The artery could be imaged from its origin at the aorta distally to identify several bifurcations. The method for transrectal imaging of the cranial mesenteric artery and its major branches required 3 distinct transducer positions. One position was used to locate the cranial mesenteric artery by imaging the caudal portion of the aorta from the aortic bifurcation cranially to the level of the cranial mesenteric artery. The second position was used to image the origin of the cranial mesenteric artery. The third position was used to image the major branches of the cranial mesenteric artery.

Progressive hydroureter and hydronephrosis were diagnosed in a dog after anastomosis of a crushed ureter. Nephrectomy was averted when partial resolution was noticed one month after the ureteral repair. The appearance of the kidney and ureter was nearly normal several months later. Conservative management should be considered in cases of partial unilateral ureteral obstruction.

Ninety-one equine aortic and cranial mesenteric arterial segments were evaluated ultrasonographically in a water bath. On the basis of pathologic evidence of verminous arteritis, arterial segments were classified into 4 categories, and the ultrasonographic characteristics of each group were evaluated. Normal arteries (class 1) were ultrasonographically characterized by a smooth luminal surface layer and uniform wall thickness and echogenicity. Arteries with only histopathologic evidence of verminous arteritis (class 2) were ultrasonographically characterized by a smooth luminal surface layer, uniform hyperechoic luminal layer. Arteries with both gross and histopathologic evidence of verminous arteritis (class 3) were characterized ultrasonographically by an irregular luminal surface layer, varying wall thickness, varying wall echogenicity, and the presence of a hyperechoic luminal layer. The ultrasonographic characteristics of arteries with luminal thrombosis (class 4) were an irregular luminal surface, varying wall thickness, and nonuniform echogenicity.

A 15-year-old male dog with chronic hematuria was found to have prolonged activated partial thromboplastin time. Results of plasma coagulation assays indicated a deficiency of prekallikrein, a plasma protein that modulates the rate of activation of factors XI and XII in the intrinsic clotting system. Patients with prekallikrein deficiency rarely have manifestations of hemorrhage. The hematuria was the result of a renal transitional cell carcinoma.