Decreased gallbladder emptying in dogs with biliary sludge or gallbladder mucocele

Biliary sludge in dogs is dismissed commonly as an incidental finding. On the other hand, gallbladder mucocele is reported increasingly in dogs and can lead to biliary obstruction or gallbladder rupture. Cholestasis is suspected to play a role in development of sludge and mucoceles, though there are no data in dogs to support this. We investigated gallbladder emptying, a key factor in biliary flow, in dogs with mobile sludge, immobile sludge, or gallbladder mucocele and in healthy controls. Gallbladder ejection fraction estimated by ultrasonography was used as the index of gallbladder emptying. The ejection fraction at 60 min after eating was significantly decreased in all three abnormal groups. Moreover, all dogs with sludge or a mucocele had gallbladder distension. These changes were the greatest in the mucocele group. Thus, biliary stasis occurs not only in dogs with gallbladder mucocele but also in dogs with biliary sludge. Cholestasis may play a role in the pathogenesis or progression of these diseases in dogs.     

ULTRASONOGRAPHIC ASSESSMENT OF SINCALIDE-INDUCED CANINE GALLBLADDER EMPTYING: AN AID TO THE DIAGNOSIS OF BILIARY OBSTRUCTION WINNER OF THE 1991 RESIDENT-AUTHORED PAPER AWARD SPONSORED BY THE AMERICAN COLLEGE OF VETERINARY RADIOLOGY

Gallbladder emptying studies using ultrasonography were performed on ten normal dogs, one normal control dog, three dogs with biliary obstruction and three dogs with nonobstructive hepatobiliary disease. An intravenous bolus of a synthetic cholecystokinin was used to induce emptying. The normal canine gallbladder emptied at least 40% of its volume within one hour of synthetic cholecystokinin (0.04 μg/kg) administration. Maximum response was seen within 5 to 20 minutes. The gallbladder in icteric dogs with nonobstructive hepatobiliary disease (1 cholecystitis, 1 cholangitis, 1 cholangiohepatitis) also emptied at least 40% of its volume within one hour. The obstructed gallbladder (1 chronic pancreatitis, 1 acute pancreatitis, 1 pancreatic mass) emptied less than 20% within one hour. A significant difference (p>0.05) in the maximum percent gallbladder emptying was found between the dogs with biliary obstruction and nonobstructed, icteric dogs. No side effects to the synthetic cholecystokinin were observed.     

Effect of enteral feeding on gallbladder function in dogs

Nutritional support in critically ill patients is a fundamental principle of patient care. Little is known about gallbladder motility during the interdigestive phase and in response to enteral feeding. The objective of this study was to investigate the effect of enteral feeding on gallbladder function in dogs. The cholagogue meal (Lipofundin infusion) was applied in four anatomical positions (jejunum, duodenojejunal junction, descending duodenum, stomach) in five healthy Beagle dogs. Gallbladder volume (GBV) was monitored by ultrasonography. Lipofundin infusion given through the feeding tube caused a maximal gallbladder contraction of 9.2% (range 3.7-13.9%) in the jejunum, 16.5% (9.1-22.1%) at the duodenojejunal junction and 26.3% (22.8-29.5%) in the descending duodenum. When the cholagogue meal was given through the mouth, it caused a mean 33.8% (28.6-46.5%) maximum gallbladder contraction in the same animals. In conclusion, we can establish that the ultrasound-guided gallbladder emptying method proved to be a useful technique for monitoring the cholagogue effect of Lipofundin meal applied in different anatomical positions of the intestine. The deeper the position of application, the smaller and shorter gallbladder contraction was evoked.     

Gallbladder Mucocele: Variables Associated with Outcome and the Utility of Ultrasonography to Identify Gallbladder Rupture in 219 Dogs (2007–2016)

Background

Gallbladder mucocele (GBM) is an increasingly recognized extrahepatic biliary disease in dogs.

Objectives

To investigate cases of GBM and identify variables associated with survival and the sensitivity and specificity of ultrasonography to identify gallbladder rupture.

Animals

Two hundred and nineteen client‐owned dogs with GBM.

Methods

Multicenter, retrospective study of dogs with GBM, presented from January 2007 to November 2016 to 6 academic veterinary hospitals in the United States. Interrogation of hospital databases identified all cases with the inclusion criteria of a gross and histopathologic diagnosis of GBM after cholecystectomy and intraoperative bacteriologic cultures of at least 1 of the following: gallbladder wall, gallbladder contents, or abdominal effusion.

Results

Two hundred and nineteen dogs fulfilled the inclusion criteria. Dogs with GBM and gallbladder rupture with bile peritonitis at the time of surgery were 2.7 times more likely to die than dogs without gallbladder rupture and bile peritonitis (P = 0.001; 95% confidence interval [CI], 1.50–4.68; n = 41). No significant associations were identified between survival and positive bacteriologic cultures, antibiotic administration, or time (days) from ultrasonographic identification of GBM to the time of surgery. The sensitivity, specificity, positive, and negative likelihood ratios for ultrasonographic identification of gallbladder rupture were 56.1% (95% CI, 39.9–71.2), 91.7% (95% CI, 85.3–95.6), 6.74, and 0.44, respectively.

Conclusion and Clinical Importance

Dogs in our study with GBM and intraoperative evidence of gallbladder rupture and bile peritonitis had a significantly higher risk of death. Additionally, abdominal ultrasonography had low sensitivity for identification of gallbladder rupture.     

Evaluation of alfalfa meal as a dietary ingredient for young Turkeys

Two experiments were conducted to evaluate alfalfa meal in the diet of turkeys aged between 1 d and 4 weeks. Turkeys were fed on diets containing 0, 5, 10 or 15% alfalfa meal from two sources. By adding increments of 5% alfalfa meal containing 20 or 17% protein in place of 4.0% ground yellow corn and 1.0% dehulled soybean meal, food efficiencies were decreased by 2.3 and 3.1%, respectively. Body weights decreased and food consumptions increased in a linear manner.

Two additional experiments were conducted to determine the effects of adding alfalfa meal to diets of turkeys aged between 4 and 8 weeks. Adding 5% alfalfa meal containing 17% protein to the diet did not affect the average body weight gain but food consumption was increased by 3.4% and the efficiency of food utilisation decreased by 3.0%.

To produce the efficiencies of food utilisation in the turkeys as observed in this study, the alfalfa meals containing 20 and 17% protein would be expected to contain about 1870 and 1320 kcal ME/kg (7.82 and 5.52 MJ/kg) respectively.     

Cholagogue-induced gallbladder emptying in the diagnosis of canine biliary obstruction

The efficacy of ultrasound-guided cholagogue-induced gallbladder emptying for differentiating obstructive from non-obstructive hepatobiliary diseases was studied in icteric dogs. In 7 healthy Beagle dogs, Lipofundin 20% infusion (2 ml/kg orally) evoked a vigorous gallbladder contraction of 44.2% (range: 35.3-57.6%) and proved to be a useful, well-tolerable meal for routine use. In 24 icteric dogs, gallbladder contraction was evoked by different cholagogues: the maximum reduction in gallbladder volume (%) for the three non-obstructive icteric dogs was 43.9% (range, 39.0-46.5%). The average gallbladder contraction of the 21 dogs with biliary obstruction was less than 5%. In conclusion, the stimulation of gallbladder contraction with orally applied magnesium sulphate (MgSO4) or Lipofundin can be well demonstrated by ultrasound in dogs. The examination of cholagogue-induced gallbladder emptying is a valuable technique in icteric patients to indicate surgical intervention.     

Pharmacokinetics of a controlled‐release liposome‐encapsulated hydromorphone administered to healthy dogs

The purpose of the study was to assess the pharmacokinetics of liposome‐encapsulated (DPPC‐C) hydromorphone administered intravenously (IV) or subcutaneously (SC) to dogs. A total of eight healthy Beagles aged 12.13 ± 1.2 months and weighing 11.72 ± 1.10 kg were used. Dogs randomly received liposome encapsulated hydromorphone, 0.5 mg/kg IV (n = 6), 1.0 mg/kg (n = 6), 2.0 mg/kg (n = 6), or 3.0 mg/kg (n = 7) SC with a 14–28 day washout between trials. Blood was sampled at serial intervals after drug administration. Serum hydromorphone concentrations were measured using liquid chromatography with mass spectrometry. Serum concentrations of hydromorphone decreased rapidly after IV administration of the DPPC‐C formulation (half‐life = 0.52 h, volume of distribution = 12.47 L/kg, serum clearance = 128.97 mL/min/kg). The half‐life of hydromorphone after SC administration of DPPC‐C formulation at 1.0, 2.0, and 3.0 mg/kg was 5.22, 31.48, and 24.05 h, respectively. The maximum serum concentration normalized for dose (C_MAX/D) ranged between 19.41–24.96 ng/mL occurring at 0.18–0.27 h. Serum hydromorphone concentrations fluctuated around 4.0 ng/mL from 6–72 h after 2.0 mg/kg and mean concentrations remained above 4 ng/mL for 96 h after 3.0 mg/kg DPPC‐C hydromorphone. Liposome‐encapsulated hydromorphone (DPPC‐C) administered SC to healthy dogs provided a sustained duration of serum hydromorphone concentrations.     

Assessment of the effects of erythromycin, neostigmine, and metoclopramide on abomasal motility and emptying rate in calves

OBJECTIVE: To determine and compare the effects of erythromycin, neostigmine, and metoclopramide on abomasal motility and emptying rate in suckling calves. ANIMALS: 6 male Holstein calves (15 to 40 days of age). PROCEDURE: Calves were monitored for 1 hour before being fed milk replacer (60 mL/kg; time, 0 minutes) and then were monitored for another 3 hours. Calves received 6 treatments in randomized order: erythromycin (8.8 mg/kg, IM) at -30 minutes; low-dose erythromycin (0.88 mg/kg, IM) at -30 minutes; erythromycin (8.8 mg/kg, IM) at -30 minutes and neostigmine (0.02 mg/kg, SC) at -30 and 90 minutes; neostigmine (0.02 mg/kg, SC) at -30 and 90 minutes; metoclopramide (0.1 mg/kg, IM) at-30 and 90 minutes; and placebo (2 mL of saline [0.9% NaCl] solution, SC) at -30 minutes. Abomasal volume was calculated from ultrasonographic measurements of abomasal width, length, and height. Abomasal motility and emptying rate were assessed by measuring luminal pressure and change in abomasal volume over time. RESULTS: Administration of erythromycin (8.8 mg/kg) increased the frequency of abomasal luminal pressure waves and the mean abomasal luminal pressure and decreased the half-time of abomasal emptying by 37%. Administration of metoclopramide, neostigmine, and low-dose erythromycin (0.88 mg/kg) did not alter abomasal motility, mean luminal pressure, or emptying rate. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that administration of erythromycin at the labeled antimicrobial dose (8.8 mg/kg, IM) exerted an immediate, marked prokinetic effect in healthy suckling calves, whereas administration of metoclopramide or neostigmine did not alter abomasal motility or emptying rate.     

Evaluation of crab meal as a dietary ingredient for young Turkeys

Adding 3 or 6% crab meal to the diets of turkeys between 1 d and 4 weeks of age resulted in their average body weight being increased by 5.2 or 6.8% and food consumption by 4.2 or 5.8%. Efficiency of food utilisation was not significantly changed. However, the addition of 5% crab meal to the diets of turkeys between 4 and 8 weeks of age resulted in average body weight gain and food consumption being increased by 1.4 and 1.3% respectively (P>0.05).

By adding 5% herring fish meal to the diets of poults from 4 to 8 weeks, body weight gain was increased by 2.0% (0.05<P<0.1), but food consumption was decreased by 2.3% and efficiency of food utilisation was increased by 4.2% indicating that fish meal contains a larger quantity of metabolisable energy than crab meal.

The addition of erythromycin at a rate of 13.5 or 20.4 mg/kg increased body weight gain by 4.5% and efficiency of food utilisation by 4.4% during the period between 4 and 8 weeks of age. No significant interactions among the dietary factors on the measurements studied in these experiments were observed.     

Effect of ammoniation of rapeseed meal on the sinapine content of the meal

1. Two experiments were conducted to study the effects of ammoni‐ation of rapeseed meal on its sinapine content.

2. In the first experiment, five samples of a low‐glucosinolate meal (produced from Regent, Candle or Tower cultivars) and one sample of a high‐glucosinolate meal were eluted by one passage of ethanol ammoniated to concentrations of 0.2, 0.5 or 1.0 M NH₃ at the ratio of 2 1 ammoniated ethanol/kg meal. Elution with 1.0M ammoniated ethanol decreased the sinapine content of the meals by as much as 80%.

3. In the second experiment, four low‐glucosinolate meals (from Candle cultivar) from a pilot processing plant were used. Two of the meals were obtained by sparging during desolventising with or without anhydrous ammonia (50 g anhydrous ammonia/kg meal) and two of the meals were produced by sparging during desolventising with or without hydrous ammonia (50 g anhydrous ammonia and 50 g steam/kg meal). Ammonia with steam caused the greatest decrease (65%) in sinapine content.

4. Total glucosinolate and 5‐vinyl‐2‐oxazolidinethione concentrations in the meals were also decreased (17 to 35%) by the ammoniation treatments in experiment 2.     

Guar meal in diets for broiler chickens

1. In two experiments each involving 2 000 Ross 1 broiler chickens in floor pens from 0 to 56 d of age, the effects of including guar meal at 50, 100 or 150 g/kg of the diet were investigated.

2. During the 0 to 28‐d period diets containing 50 or 100 g guar meal/kg supported only 85 and 69%, respectively, of the growth supported by the control diet, whereas during 28 to 56 d, birds fed on diets containing 100 or 150 g guar meal/kg gained 90 and 86% of the weight gained by control birds.

3. Neither toasting the meal, steam pelleting diets containing the meal nor supplementing these diets with 5 g methionine/kg had any appreciable effect on performance.

4. Addition of either of two enzyme preparations, MKC hemicellulase or betaganase M, improved growth; birds receiving 100 or 150 g guar meal/kg gaining 96 and 89%, respectively, of the weight gained by control birds from 28 to 56 d of age.     

Furosemide continuous rate infusion diluted with 5% dextrose in water or hypertonic saline in normal adult dogs: a pilot study

Objective

The goal of this study was to investigate the short-term safety and diuretic efficacy of furosemide constant rate infusion (CRI) diluted with 5% dextrose in water (D5W) compared to dilution with 2.4% hypertonic saline in healthy dogs.

Pharmacokinetics of once-daily amikacin in healthy foals and therapeutic drug monitoring in hospitalized equine neonates

The objectives of this study were to investigate the pharmacokinetics of once-daily amikacin in healthy neonates, to determine amikacin concentrations in hospitalized foals, and to determine the minimum inhibitory concentrations (MICs) of amikacin against gram-negative isolates from blood cultures in septic foals. Median half-life, clearance, and volume of distribution of amikacin in healthy 2- to 3-day-old foals after administration of an intravenous bolus of amikacin (25 mg/kg) were 5.07 hours (4.86-5.45 hours), 1.82 mL/min/kg (1.35-1.97 mL/min/kg), and 0.785 L/kg (0.638-0.862 L/kg), respectively. Statistically significant (P <.05) decreases in area under the curve (14% decrease), mean residence time (19% decrease), and C24h plasma amikacin concentrations (29% decrease) occurred between days 2-3 and 10-11. Plasma amikacin concentrations in healthy foals at 0.5 hours (C0.5h) were significantly higher (P = .02) than those of hospitalized foals. Sepsis, prematurity, and hypoxemia did not alter amikacin concentrations. The MIC at which 90% of all gram-negative isolates from equine neonatal blood cultures were inhibited by amikacin was 4 microg/mL, suggesting that amikacin C0.5h of 40 microg/mL should be targeted to achieve a maximum serum concentration to MIC ratio of 10:1. The proportion of foals with C0.5h 40 microg/mL was significantly higher (P < .0001) in hospitalized foals receiving a dose of amikacin at 25 mg/kg (22/24 or 92%) than in foals receiving a dose at 21 mg/kg (9/25 or 36%), whereas no difference was found in the proportion of foals with C24h concentrations > or = 3 microg/mL between the 2 groups. An initial dose at 25 mg/kg is recommended for once-daily amikacin in equine neonates.     

Pharmacokinetics of erythromycin estolate and erythromycin phosphate after intragastric administration to healthy foals

OBJECTIVE: To determine pharmacokinetics and plasma concentrations of erythromycin and related compounds after intragastric administration of erythromycin phosphate and erythromycin estolate to healthy foals. ANIMALS: 11 healthy 2- to 6-month-old foals. PROCEDURE: Food was withheld from foals overnight before intragastric administration of erythromycin estolate (25 mg/kg of body weight; n = 8) and erythromycin phosphate (25 mg/kg; 7). Four foals received both drugs with 2 weeks between treatments. Plasma erythromycin concentrations were determined at various times after drug administration by use of high-performance liquid chromatography. Maximum plasma peak concentrations, time to maximum concentrations, area under plasma concentration versus time curves, half-life of elimination, and mean residence times were determined from concentration versus time curves. RESULTS: Maximum peak concentration of erythromycin A after administration of erythromycin phosphate was significantly greater than after administration of erythromycin estolate (2.9 +/- 1.1 microg/ml vs 1.0 +/- 0.82 microg/ml). Time to maximum concentration was shorter after administration of erythromycin phosphate than after erythromycin estolate (0.71 +/- 0.29 hours vs 1.7 +/- 1.2 hours). Concentrations of anhydroerythromycin A were significantly less 1 and 3 hours after administration of erythromycin estolate than after administration of erythromycin phosphate. CONCLUSIONS AND CLINICAL RELEVANCE: Plasma concentrations of erythromycin A remained > 0.25 microg/ml (reported minimum inhibitory concentration for Rhodococcus equi) for at least 4 hours after intragastric administration of erythromycin phosphate or erythromycin estolate, suggesting that the recommended dosage for either formulation (25 mg/kg, q 6 h) should be adequate for treatment of R equi infections in foals.     

Effects of sildenafil citrate on five dogs with Eisenmenger's syndrome

Objectives : To determine the effect of sildenafil for dogs with Eisenmeger's syndrome and secondary erythrocytosis. Methods : This is a prospective, single arm, open‐label study. Five clinical dogs with Eisenmeger's syndrome and secondary erythrocytosis were included. New York Heart Association functional class, packed cell volume, pulmonary artery acceleration time to ejection time ratio and serum erythropoietin concentration were evaluated before and after sildenafil therapy (0·5 mg/kg, twice a day). Results : New York Heart Association functional class was significantly improved after one (median 2; range 1 to 2, P=0·031) and three months (median 2; range 1 to 2, P=0·031) of sildenafil therapy, compared with the baseline (median 3, range 2 to 3). Packed cell volume was significantly decreased after three months (median 59%; range 56 to 63, P=0·031) of therapy, compared with the baseline (median 71%; range 58 to 74). Acceleration time to ejection time ratio had increased and serum erythropoietin concentration had decreased particularly after 1 month of therapy, but there was no statistical significance. Clinical Significance : Sildenafil improved the clinical signs and secondary erythrocytosis in dogs with Eisenmeger's syndrome. Sildenafil therapy could be a useful treatment for dogs with Eisenmeger's syndrome.     

Comparative pharmacokinetics of amikacin in Greyhound and Beagle dogs

The purpose of the study was to compare the pharmacokinetics of amikacin administered i.v., to Greyhound and Beagle dogs and determine amikacin pharmacokinetics administered subcutaneously to Greyhounds. Amikacin was administered i.v. at 10 mg/kg to six healthy Greyhounds and six healthy Beagles. The Greyhounds also received amikacin, 10 mg/kg s.c. Plasma was sampled at predetermined time points and amikacin concentrations determined by a fluorescence polarization immunoassay (FPIA).
The volume of distribution was significantly smaller in Greyhounds (mean = 176.5 mL/kg) compared to Beagles (234.0 mL/kg). The C ₀ and AUC were significantly larger in Greyhounds (86.03 μg/mL and 79.97 h·μg/mL) compared to Beagles (69.97 μg/mL and 50.04 h·μg/mL). The plasma clearance was significantly lower in Greyhounds (2.08 mL/min/kg) compared to Beagles (3.33 mL/min/kg). The fraction of the dose absorbed after s.c. administration to Greyhounds was 0.91, the mean absorption time was 0.87 h, and the mean maximum plasma concentration was 27.40 μg/mL at 0.64 h.
Significant differences in the pharmacokinetics of amikacin in Greyhounds indicate it should be administered at a lower dose compared to Beagles. The dose in Greyhounds to achieve a C _max: AUC  ≥ 8 for bacteria (with an MIC  ≤ 4 μg/mL) is 12 mg/kg q24 h compared to 22 mg/kg q24 in Beagles.     

The use of 25% human serum albumin: outcome and efficacy in raising serum albumin and systemic blood pressure in critically ill dogs and cats

Objective: To report on the use of 25% human serum albumin (25% HSA) (Plasbumin®), associated outcome, and efficacy in raising serum albumin and systemic blood pressure (BP) in critically ill dogs and cats. Design: Retrospective clinical study. Animals: Client‐owned cats and dogs. Interventions: Administration of 25% HSA. Measurements and main results: The medical records of 66 animals (64 dogs, 2 cats) at the Ontario Veterinary College, which received 25% HSA (Plasbumin®) from June 1997 to December 2001 were reviewed for age, body weight, clinical problems, albumin and globulin (g/L) levels pre‐ and within 18‐hour post‐transfusion and upon discharge from hospital, total solids (TS), systolic and diastolic BP pre‐ and post‐transfusion total volume administered, adverse reactions, blood products and synthetic colloids used, and outcome. Twenty‐five percent HSA was prescribed for a range of clinical problems, which were grouped into 6 categories for analysis. The age range was 4 months–12 years and body weight range 1.4–65 kg. The maximum volume administered to any dog was 25 mL/kg, mean volume administered was 5 mL/kg, maximum volume given as a slow push or bolus was 4 mL/kg with a mean of 2 mL/kg volume. The range for a constant rate infusion (CRI) was 0.1–1.7 mL/kg/hr over 4–72 hours. Forty‐seven (71%) animals survived to discharge; 11(16%) were euthanized, and 8 (12%) died. Serum albumin and TS increased significantly (P<0.0001) above pre‐transfusion levels as did systolic BP (P<0.01). Conclusions: Twenty‐five percent HSA can be safely administered to critically ill animals, and an increase in albumin levels and systemic BP can be expected.     

Pharmacokinetic properties of toceranib phosphate (Palladia™, SU11654), a novel tyrosine kinase inhibitor,in laboratory dogs and dogs with mast cell tumors

Yancey, M. F., Merritt, D. A., Lesman, S. P., Boucher, J. F., Michels, G. M. Pharmacokinetic properties of toceranib phosphate (Palladia?, SU11654), a novel tyrosine kinase inhibitor, in laboratory dogs and dogs with mast cell tumors. J. vet. Pharmacol. Therap. 33 , 162–171. Toceranib phosphate (Palladia?, SU11654), an oral tyrosine‐kinase inhibitor, is under investigation for the treatment of mast cell tumors in dogs. The pharmacokinetics of toceranib phosphate has been characterized in dogs. Means of the following pharmacokinetic parameters were estimated following a 1.0 mg/kg i.v. dose to laboratory beagles: plasma clearance of 1.45 L/kg/h, volume of distribution of 29.7 L/kg, and terminal half‐life of 17.7 h. Following single oral doses of 3.25 mg/kg administered to laboratory beagles, mean C_max estimates ranged from 68.6 ng/mL to 112 ng/mL with t_max ranging from 5.3 h and 9.3 h postdose. Terminal half‐life was estimated at 31 h. Oral bioavailability was 76.9%. There were no statistically significant (P > 0.05) differences with any pharmacokinetic parameter due to fed/fasted state or with time during 13 weeks of every‐other‐day dosing at 3.25 mg/kg. Toceranib concentrations were proportional with dose over the range of 2.0 to 6.0 mg/kg. The pharmacokinetics of toceranib in client‐owned dogs of a variety of pure and mixed breeds with mast cell tumors was similar to that in healthy laboratory dogs. In summary, toceranib phosphate exhibited moderate clearance, a high volume of distribution, and a moderate elimination half‐life. After a single oral dose at 3.25 mg/kg, the concentration vs. time curve showed broad, sustained exposure with measurable concentrations for more than 48 h. These pharmacokinetic parameters support every‐other‐day administration of toceranib phosphate at an initial dose of 3.25 mg/kg for the treatment of mast cell tumors in dogs.     

Gallbladder disease in Shetland Sheepdogs: 38 cases (1995-2005)

OBJECTIVE: To determine risk, clinical features, and treatment responses for gallbladder disorders in Shetland Sheepdogs. DESIGN: Retrospective case-control study. ANIMALS: 38 Shetland Sheepdogs with gallbladder disease. PROCEDURES: Medical records were reviewed for signalment, history, physical findings, laboratory results, imaging features, coexistent illnesses, histologic findings, treatments, and survival rates. RESULTS: Mature dogs with gastrointestinal signs were predisposed (odds ratio, 7.2) to gallbladder disorders. Gallbladder mucocele was confirmed in 25 dogs. Concurrent problems included pancreatitis, hyperlipidemia, corticosteroid excess, hypothyroidism, protein-losing nephropathy, diabetes mellitus, cholelithiasis, and gallbladder dysmotility. Mortality rate was 68% with and 32% without bile peritonitis. Nonsurvivors had high WBC and neutrophil count and low potassium concentration. Although preprandial hypercholesterolemia, hypertriglyceridemia, and high serum liver enzyme activities were common, gallbladder disease was serendipitously discovered in 11 of 38 dogs. Histologic examination (n=20 dogs) revealed gallbladder cystic mucosal hyperplasia in 20 dogs, cholecystitis in 16, periportal hepatitis in 9, and vacuolar hepatopathy in 7. Surgery included cholecystectomy (n=17) and cholecystoenterostomy (4). In 1 hyperlipidemic dog without clinical signs, gallbladder mucocele resolved 6 months after beginning use of a fat-restricted diet and ursodeoxycholic acid. CONCLUSIONS AND CLINICAL RELEVANCE: Shetland Sheepdogs are predisposed to gallbladder disorders, with mucoceles and concurrent dyslipidemia or dysmotility in many affected dogs. Most dogs were without clinical signs during mucocele development. Low survival rate after cholecystectomy in clinically affected dogs suggested that preemptive surgical interventions may be a more appropriate treatment strategy.     

Glomerular Filtration Rate and Renal Volume in Dogs with Congenital Portosystemic Vascular Anomalies before and after Surgical Ligation

Glomerular filtration rate (GFR) and renal volume were evaluated in dogs with confirmed portosystemic vascular anomalies (PSVA) before and after surgical ligation of their PSVA. Pre- and postligation CBC, serum biochemistry, urinalysis, abdominal ultrasonography with measurement of renal volume, and per rectal scintigraphy were performed to document resolution of abnormalities consistent with portosystemic shunting. GFR was estimated by plasma 99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA) clearance before (n = 21) and after (n = 12) surgical correction of PSVA. Preligation 99mTc-DTPA GFR was increased (median, 5.64 mL/minute/kg; range, 3.53-8.49 mL/minute/kg; reference range, 2.83-4.47 mL/minute/kg) in 81% (17/21) of dogs. Postligation 99mTc-DTPA GFR decreased in all 12 evaluated dogs (median change = -42%; P < .001). Preligation renal volume was above the reference range for the left and right kidneys in 71% (10/14) and 69% (11/16) of dogs evaluated, respectively. Right renal volume decreased significantly (n = 5; median change, -45%; P = .03) after surgical ligation of PSVA. These findings document increased GFR and renal volume in dogs with PSVA, which may explain in part the low blood urea nitrogen and serum creatinine concentrations encountered in these dogs. Knowledge of changes in GFR associated with PSVA ligation may prove helpful in the anesthetic, drug, and dietary management of affected dogs.