Tibial plateau angles with and without cranial cruciate ligament rupture

The tibial plateau angles (TPA) of dogs with and without cranial cruciate ligament (CrCL) injuries were evaluated and further compared to the TPAs of dogs from a previous population and of wolves. Similar TPA measurements were found in all groups, suggesting that any possible changes in breeding practises, breed preferences, nutrition or other factors have not significantly influenced the TPA over time. Moreover, a difference was not found in the TPA between any group and the group affected with CrCL injury, suggesting that the TPA is not a clinically relevant predisposing factor in the development of canine CrCL rupture.

Überwachung von TSE bei kleinen Wiederkäuern und Schweinen: Eine Pilotstudie

Switzerland is controlling Transmissible Spongiform Encephalopathies (TSE) in cattle (BSE) and small ruminants (scrapie). Since BSE is potentially transmissible to sheep, goats or pigs through feeding of contaminated meat and bone meal, implementation of an active surveillance programme for TSE in these species is discussed. The aim of this pilot study was to obtain preliminary data on the prevalence ofTSE and other neurological disorders in these populations. For that purpose, a total of 398 perished and 825 slaughtered adult small ruminants and pigs was examined for the presence of neuropathological changes. None of these animals revealed positive for TSE. However, the investigations demonstrated that perished sheep and goats exhibited a higher prevalence of relevant neuropathological changes when compared with slaughtered animals. From these results, it is concluded that perished small ruminants are probably a risk population for TSE and should be considered as target populations for an active surveillance programme.

Clinical application and reliability of a post abdominal surgery pain assessment scale (PASPAS) in horses

The aim of this study was to refine a multi-dimensional scale based on physiological and behavioural parameters, known as the post abdominal surgery pain assessment scale (PASPAS), to quantify pain after laparotomy in horses. After a short introduction, eight observers used the scale to assess eight horses at multiple time points after laparotomy. In addition, a single observer was used to test the correlation of each parameter with the total pain index in 34 patients, and the effect of general anaesthesia on PASPAS was investigated in a control group of eight horses. Inter-observer variability was low (coefficient of variation 0.3), which indicated good reliability of PASPAS. The correlation of individual parameters with the total pain index differed between parameters. PASPAS, which was not influenced by general anaesthesia, was a useful tool to evaluate pain in horses after abdominal surgery and may also be useful to investigate analgesic protocols or for teaching purposes.

Occurrence of systemic hypertension in dogs with acute kidney injury and treatment with amlodipine besylate

OBJECTIVES

To describe the occurrence of systemic hypertension in dogs with acute kidney injury and the efficacy of amlodipine besylate for its treatment.

METHODS

This retrospective study included 52 dogs with acute kidney injury (2007 to 2008) grouped based on the use of amlodipine in their treatment. Systemic blood pressure was measured with an oscillometric device at admission, before, during, and after amlodipine therapy.

RESULTS

Occurrence of systolic systemic hypertension (≥160 mmHg) and severe systolic systemic hypertension (≥180 mmHg) was 37% and 15% at admission and increased with hospitalisation to 81% and 62%, respectively. Twenty-two dogs were treated with amlodipine, at a median daily dosage of 0·38 mg/kg (interquartile range 0·28 to 0·49) divided in one to two applications per day. Amlodipine therapy was associated with a decrease in systolic systemic blood pressure of 24 mmHg (12 to 34) and a correction of severe systemic hypertension in 10 of 11 dogs within 24 hours. Overall, 73% of the dogs survived with a significantly lower proportion of survivors in treated compared to non-treated dogs (59% versus 83%, respectively, P=0·05).

CLINICAL SIGNIFICANCE

Results of this study reveal that systemic hypertension is common in canine acute kidney injury and that treatment with amlodipine is beneficial in reducing systemic hypertension. The potential effect of amlodipine on global outcome requires prospective assessment.

[Occurrence of Clostridium perfringens type A and type C in piglets of the Swiss swine population]

Necrotizing enteritis (NE) of newborn piglets still represents an economical problem in Swiss pig breeding and production. The aim of our study was to identify risk factors for NE and evaluate the prevalence of C. perfringens with the toxingenes cpb and cpb2 in Swiss pig breeding farms. The prevalence of theses C. perfringens was investigated using fecal swabs followed by bacteriological culturing and genotyping. Close proximity to other breeding farms and large herd sizes were shown to predispose to NE. C. perfringens type C, carrying the genes cpa, cpb and cpb2 were frequently identified in herds with acute outbreaks of NE. Farms not affected by NE or those using prophylactic vaccination against NE were predominantly positive for C. perfringens type A strains with cpb2 and showed much lower prevalence of C. perfringens type C, compared to acutely affected herds. Our results demonstrate that C. perfringens type A strains with cpb2 are not associated with NE. Besides typical necropsy finding, only the identification of cpb can be used for the diagnosis of NE in affected herds.

Influence of surgical approach on the efficacy of the intervertebral disk fenestration: a cadaveric study

OBJECTIVES

To investigate the influence of different approach angles on the amount of nucleus pulposus removed during intervertebral disc fenestration in dogs.

METHODS

Twenty cadavers of beagle dogs were randomly divided into four groups: a control group and three treatment groups in which intervertebral fenestration was performed using either a dorsal, dorsolateral or lateral approach between the 12th thoracic and second lumbar spaces. The volume of nucleus pulposus, the weight of the residual nucleus pulposus and the angle of the working sector were measured. The ratio of the residual nucleus pulposus weight to the nucleus pulposus volume was used to evaluate the efficacy of the performed fenestration. Data were analysed with Kruskal-Wallis analysis of variance between groups on ranks with correction for ties and Bonferroni correction for multiple comparisons. Correlation between ratio and working angle was calculated using a Spearman's rank test (P<0.05).

RESULTS

The calculated ratio of nuclear weight to volume was significantly less in the lateral approach group than that in the other groups. The working sector was widest in the dorsolateral approach group, but this did not correlate with efficient fenestration.

CLINICAL SIGNIFICANCE

Using the lateral approach for intervertebral disc fenestration may increase the efficiency of the fenestration procedure.

Immune dysregulation in flea allergy dermatitis—A model for the immunopathogenesis of allergic dermatitis

BACKGROUND

Flea allergy dermatitis (FAD) is a common skin disease in dogs and can be induced experimentally. It often coexists with other allergic conditions. So far no studies have investigated the quantitative production of cytokine mRNA in skin biopsies and peripheral blood mononuclear cells (PBMC) in flea allergic dogs.

OBJECTIVE

The aim of our study was to improve the understanding of the immunopathogenesis of allergic dermatitis as a response to fleabites.

MATERIAL AND METHODS

Allergic and non-allergic dogs were exposed to fleas. Before and after 4 days of flea exposure mRNA was isolated from biopsies and PBMC. Production of chymase, tryptase, IL-4, IL-5, IL-13, TNF-alpha and IFN-gamma mRNA was measured by real-time RT-PCR. The inflammatory infiltrate in the skin was scored semi-quantitatively. The number of eosinophils, mast cells (MC) and IgE+ cells/mm2 was evaluated to complete the picture.

RESULTS

FAD was associated with a higher number of MC before flea exposure and with a significant increase of eosinophils after flea exposure as compared to non-allergic dogs. The number of IgE+ cells was higher in allergic dogs before and after flea exposure. In allergic dogs mRNA for most cytokines and proteases tested was higher before flea exposure than after flea exposure. After exposure to fleas an increased mRNA production was only observed in non-allergic dogs. In vitro stimulation with flea antigen resulted in a decreased expression of most cytokines in allergic dogs before flea exposure. In contrast, in PBMC, only increased levels of IL-4 and IL-5 mRNA were observed in allergic dogs before flea exposure. However, after flea exposure and additional stimulation with flea antigen the production of mRNA for all cytokines tested was significantly increased in allergic dogs.

CONCLUSION

We demonstrated that the response in biopsies and PBMC is different and that FAD is associated with a TH2 response.

Inhalation anaesthesia for castration of newborn piglets: experiences with isoflurane and isoflurane/NO

The aim of this study was to evaluate the inhalation anaesthesia with isoflurane and isoflurane/N2O by mask induction for routine castration of piglets under 14 days of age.

MATERIAL AND METHODS

Eighty-five male piglets aged between 4 and 12 days were used in a matched pair test. Two piglets of the same litter with the same weight were selected. One was castrated with, the other without anaesthesia. Induction was performed with either isoflurane (group ISO) or isoflurane/nitrous oxide (group ISO/N2O) in oxygen through a modified bain-breathing system. Induction time was 90 and 60 s for group ISO and group ISO/N2O, respectively. The disappearance of the palpebral reflex was recorded. The reaction of the piglets during castration was judged according to a scoring system separately for both testicles during skin incision and dissection of the spermatic cord. The scores were added and mean values were calculated. Total anaesthesia time, castration time and quality of recovery was recorded. Blood was collected from all piglets immediately after castration for measurement of ACTH and beta-endorphin values. Statistical analysis were performed by the Kruskal-Wallis test for nonparametric data and one-way anova (NCSS 2000, Kaysville, UT, USA).

RESULTS

Induction of anaesthesia proved to be smooth in all cases. The palpebral reflex disappeared after 36.5 s in group ISO/N2O versus 51 s in group ISO. Mean castration scores were 0.6 in group ISO and 0 in group ISO/N2O, whereas 7.7 in piglets with no anaesthesia. These scores were significantly different. Mean anaesthesia time was 128 s (30-390) for group ISO and 123 s (70-220) for group ISO/N2O. No deaths occurred. The differences in the levels of ACTH and beta-endorphins in the blood plasma in the different groups showed no statistical difference.

DISCUSSION

This study demonstrates that isoflurane or isoflurane/N2O anaesthesia by mask induction proves to be a safe, short and reliable method in piglets undergoing castration. Reaction to the castration procedure were significantly reduced. Stress hormone values were not different between the groups because of a large individual difference.

Influence of food composition on splanchnic blood flow during digestion in unsedated normal dogs: a Doppler study

The effect of dietary components in gastrointestinal blood flow was investigated non-invasively in dogs. Doppler ultrasound (US) waveform analysis of the celiac artery (CA) and the cranial mesenteric artery (CMA) of eight healthy dogs was performed both in the fasting state and at 20, 40, 60 and 90 min after feeding maintenance, high protein, high carbohydrate and high fat diets. Resistive index (RI), pulsatility index (PI) and the percentage differences between measurements were calculated. In fasted dogs, the CA showed significantly (p<0.05) lower resistance than the CMA. With all diets, post-prandial RI and PI values decreased significantly in both vessels (CA: RI=-12-13%; PI=-25-29%; CMA: RI=-13-15%; PI=-27-29% [p<0.05]), and in all cases significantly earlier in the CA than in the CMA (p<0.05). With all diets except high fat the maximum decrease in RI and PI was reached in the CA at 40 min and in the CMA at 60 min. High fat diets were unique in that the maximum decrease in RI and PI in the CMA occurred earlier (at 20 min) and values were slower to return to normal (p<0.05). We conclude that Doppler US can be used in dogs to quantify significant differences in the response of splanchnic blood flow to different dietary components.

Application of Prionics Western blotting procedure to screen for BSE in cattle regularly slaughtered at Swiss abattoirs

Disease-specific PrP (PrP(Sc)) is at least part of the infectious particle (prion) causing bovine spongiform encephalopathy (BSE) or scrapie in sheep. Digestion with protease allows a distinction between normal PrP (PrP(C)) and PrP(Sc) i.e. PrP(C) is completely digested while PrP(Sc) is cleaved at the N-terminus leading to a fragment of reduced molecular weight (PrP 27-30). Detection of this fragment by Western blotting has been described more than a decade ago for rodent PrP. We have now optimized the technique in order to allow rapid analysis of hundreds of samples per day. Here we report the application of this technique to the analysis of 3000 regularly slaughtered cattle from Swiss abattoirs. For comparison all the animals were subsequently examined by classical methods (i.e. histology and immunohistochemistry). All but one animal were negative for BSE by all methods. The Western blot positive animal was confirmed to be a BSE case and the carcass was removed from the food chain. We conclude that it is feasible to examine slaughtered cattle on a routine basis without causing delays to the meat processing industry.

Necrosis of hippocampus and piriform lobe in 38 domestic cats with seizures: a retrospective study on clinical and pathologic findings

The clinical records of 38 cats (1985-1995) with a neuropathologically confirmed diagnosis of necrosis of the hippocampus and occasionally the lobus piriformis were evaluated retrospectively. There was no sex or breed predisposition. Most cats were between 1 and 6 years of age (mean age 35 months) and had either generalized or complex-partial seizures of acute onset and rapid progression. The seizures had a tendency to become recurrent and to present as clusters or even status epilepticus later in the course of the disease. Fourteen cats died spontaneously, and 24 were euthanized. Histopathologic examination revealed bilateral lesions restricted to the hippocampus and occasionally the lobus piriformis. The lesions seemed to reflect different stages of the disease and consisted of acute neuronal degeneration to complete malacia, affecting mainly the layer of the large pyramidal cells but sometimes also the neurons of the dentate gyrus and the piriform lobe. The clinical, neuropathologic, and epidemiologic findings suggest that the seizures in these cats were triggered by primary structural brain damage, perhaps resulting from excitotoxicity. The cause remains unknown, but epidemiologic analysis suggests an environmental factor, probably a toxin.

Validation of a western immunoblotting procedure for bovine PrP(Sc) detection and its use as a rapid surveillance method for the diagnosis of bovine spongiform encephalopathy (BSE)

In this report we document the results of several independent studies testing the sensitivity, specificity and reliability of the Prionics Western blotting (PWB) procedure to detect bovine and ovine disease-specific, protease-resistant prion protein (PrP(Sc)). Validation of the technique was obtained by blind analysis of samples from cattle affected with bovine spongiform encephalopathy (BSE), clinically normal animals or cattle with neurological diseases unrelated to BSE. Overall, very high sensitivity, specificity and reliability was observed. It became clear that sampling of the correct brain region and the method used for protein extraction are important factors for correct diagnosis. Furthermore, we tested the usefulness of the PWB technique as an instrument for surveillance purposes. We analyzed animals from a culling scheme as well as older animals from abattoirs to determine the number of subclinical BSE cases detectable by histopathological examination, immunohistochemistry for PrP(Sc) and PWB. In both studies, BSE-affected animals with no overt clinical symptoms were detected. These results demonstrate the usefulness of the PWB procedure in surveillance systems serving as a rapid diagnostic tool to identify animals subclinically infected with BSE.

Corynebacterium pseudotuberculosis infection in horses: 538 cases (1982-1993)

OBJECTIVE

To describe clinical manifestations of Corynebacterium pseudotuberculosis infection in horses and to evaluate diagnostic methods for identification of this disease.

DESIGN

Retrospective case series.

ANIMALS

538 horses with a diagnosis of C pseudotuberculosis infection.

RESULTS

Median age of horses with external abscesses was similar to that in horses with internal abscesses. Breed and sex did not appear to be associated with infection. Cases were detected during all 12 months; however, the disease was most common in the fall and early winter, with the highest incidence in September, October, and November in every year. Most horses (492/538, 91.4%) had a single episode of infection, without recurrence in subsequent years. Of 538 horses, 308 had pectoral abscesses, although infection was documented in many other anatomic locations. Forty-two horses had internal abscesses involving the abdomen or thoracic cavity. Corynebacterium pseudotuberculosis infection was readily identified by bacterial culture of aspirate samples from abscesses. The synergistic hemolysis inhibition test was useful for diagnosis of internal abscesses; however, it was unreliable for the diagnosis of external abscesses. Horses with external abscesses responded well to conventional treatment, in contrast to those with internal abscesses. The overall case fatality was low (3.9%), and was considerably lower for horses with external abscesses (0.8%) than for horses with internal abscesses (40.5%).

CLINICAL IMPLICATIONS

Serology (synergistic hemolysis inhibition titers > or = 512) is useful for diagnosis of internal abscesses, but not reliable for diagnosis in horses with external abscesses. Prognosis for horses with internal abscesses is considerably poorer than for those with external abscesses.

Cryopreservation of Babesia caballi cultures

Babesia caballi cultures were cryopreserved with a solution of 10% (w/v) polyvinylpyrrolidone 40 as cryoprotectant. Samples were cooled at rates of 1, 10, 30 and 100 degrees C min-1 using a programmable freezer. Additionally, a styrofoam box designed to cool samples at an approximate rate of 10 degrees C min-1 when placed in a -80 degrees C freezer was used. Samples were stored in liquid nitrogen, thawed rapidly and inoculated into cultures. Although, a high loss of infectivity was observed after cryopreservation, cultures could be initiated reliably from cryo-stabilates frozen at a rate of 10 and 30 degrees C min-1 or frozen with the styrofoam box.