Erosive stomatitis in a white pelican (Pelecanus onocrotalus) caused by Piagetiella titan (Mallophaga: Menoponidae)

Two white pelicans at the garden of a restaurant in Bey?ehir, a county of Konya province were examined for the presence of ectoparasites. Nine lice were collected from the oral cavity of one of them. They were identified as Piagetiella titan. Diffuse erosions, erosive ulcers covered by dried yellowish-brown exudate and petechial haemorrhages were observed in oral mucosa.     

Prevalence and characteristics of quinolone resistance in Escherichia coli in veal calves

Quinolone resistance is studied and reported increasingly in isolates from humans, food-producing animals and companion animals. Resistance can be caused by chromosomal mutations in topoisomerase genes, plasmid-mediated resistance genes, and active transport through efflux pumps. Cross sectional data on quinolone resistance mechanisms in non-pathogenic bacteria from healthy veal calves is limited. The purpose of this study was to determine the prevalence and characteristics of quinolone resistance mechanisms in Escherichia coli isolates from veal calves, after more than 20 years of quinolone usage in veal calves. MIC values were determined for all isolates collected as part of a national surveillance program on antimicrobial resistance in commensal bacteria in food-producing animals in The Netherlands. From the strains collected from veal calves in 2007 (n=175) all isolates with ciprofloxacin MIC ≥ 0.125 mg/L (n=25) were selected for this study, and screened for the presence of known quinolone resistance determinants. In this selection only chromosomal mutations in the topoisomerase type II and IV genes were detected. The number of mutations found per isolate correlated with an increasing ciprofloxacin MIC. No plasmid-mediated quinolone resistance genes were found. The contribution of efflux pumps varied from no contribution to a 16-fold increase in susceptibility. No correlation was found with the presence of resistance genes of other antimicrobial classes, even though all quinolone non-wild type isolates were resistant to 3 or more classes of antibiotics other than quinolones. Over twenty years of quinolone usage in veal calves in The Netherlands did not result in a widespread occurrence of plasmid-mediated quinolone resistance, limiting the transmission of quinolone resistance to clonal distribution.     

COMPUTED TOMOGRAPHY OF CHOLESTERINIC GRANLOMAS IN THE CHOROID PLEXUS OF HORSES

Cholesterinic granulomas are tumor-like masses in the choroid plexuses of horses. This report describes the computed tomographic findings in four horses with cholesterinic granulomas, including the clinical and the pathologic features. All four horses had bilateral cholesterinic granulomas in the lateral ventricles. Computed tomographic images clearly delineated the masses, the opacity of the granulomas, and the enhancement pattern after intravenous bolus injection of contrast medium; these factors varied considerably. Additional CT findings were symmetric or asymmetric widening of the lateral ventricles.     

Comparison of three biological control agents against cucumber powdery mildew (Sphaerotheca fuliginea) in semi-commercial-scale glasshouse trials

The effect of three reported biological control agents, Ampelomyces quisqualis, Verticillium lecanii and Sporothrix flocculosa, was tested against cucumber powdery mildew (Sphaerotheca fuliginea). Two glasshouse experiments, one in the summer and one in winter/spring were conducted on a semi-commercial scale. In both experiments, a susceptible and a partially resistant cultivar were used. In the second experiment, the additional effect of integration of biological control and silicon amendments to the nutrient solution was also assessed. In both experiments, A. quisqualis did not control the disease. V. lecanii had a small effect on powdery mildew in the first experiment but not in the second. S. flocculosa gave the best control of powdery mildew in both experiments. In the first experiment, weekly application of S. flocculosa reduced disease in the partially resistant cultivar to the same level as a treatment in which the fungicides bupirimate and imazalil were each applied once. Addition of silicon in the nutrient solution in a concentration of 0.75 mM reduced disease by 10–16%, averaged over all treatments. There was no interaction between silicon and the biocontrol agents. Yield was recorded in the second experiment and was significantly increased by the fungicide treatment compared to the control in the partially resistant cultivar. Yield in the treatment with S. flocculosa was not significantly different from the fungicide treatment in this cultivar. Silicon had no effect on yield in either cultivar.     

Development of the navicular bone in foetal and young horses, including the arterial supply

A macroscopic, arteriographic and histological study of the development and the arterial anatomy of the navicular bone of 33 foetuses and 55 young horses is described. After 125 days of gestation the blood supply consists of two routes: one situated in the superficial layer of the fibrocartilage and the other similar to the blood supply of the navicular bone of the normal mature horse. After 270 days gestation, the blood vessels in the fibrocartilage gradually regressed and retracted until they have disappeared at six months after birth. At two months after birth the first macroscopic thinning of the fibrocartilage was noticed. From seven months to one year about 45 per cent of the navicular bones showed a slight thinning of the fibrocartilage. A positive correlation was found between radiographic abnormalities (ie enlargement of the nutrient foramina) and the frequency of thinning of the fibrocartilage. Radiographic abnormalities were first recognised 14 days after birth, whereas the arteriogram showed the first changes such as fewer or no arteries entering distally at the distal extremities at 10 weeks after birth. At four weeks after birth the first arterial wall changes were found, ie intimal thickening with or without splitting of the internal elastic membrane. From that age onward, the number of navicular bones with arterial wall changes gradually increased. Starting at five months after birth only 6 to 20 per cent of the arteries in the navicular bones without radiographic abnormalities showed arterial wall changes. However, the navicular bones with radiographic abnormalities showed arterial wall changes in 25 to 80 per cent of the arteries.     

Radiographic and radionuclide lung perfusion imaging in healthy calves and calves naturally infected with bovine respiratory syncytial virus.

Nine calves between three and 18 weeks old with serologically confirmed natural bovine respiratory syncytial virus infection were examined clinically, radiographically and by radionuclide lung perfusion imaging. The results were compared with those from seven healthy calves. The diseased calves were euthanased and examined pathologically, virologically and bacteriologically. The clinical signs indicated that the disease was in an acute stage. Radiography of the diseased animals revealed cysts, corresponding morphologically with bullous emphysema, and infiltrations roughly corresponding in distribution with atelectatic and, or, pneumonic areas. Radionuclide lung perfusion imaging revealed no perfusion shifts between the left and right lungs and a normal perfusion pattern in five of the nine diseased calves. The abnormalities in the perfusion patterns of three calves were probably caused by anatomical disorders such as cysts and pleural adhesions, but no cause of the abnormality could be found in one calf. These findings suggest that in calves infected with bovine respiratory syncytial virus, the normal perfusion pattern is maintained until anatomical disorders occur. The pathological examination and radiography revealed that the cranioventral lung fields were particularly poorly ventilated. This finding and the normal perfusion pattern indicate that these parts of the lungs are probably the sites where shuntings and perfusion-ventilation mismatchings occur.     

The radiographic development of the distal and proximal double contours of the equine navicular bone on dorsoproximal-palmarodistal oblique (upright pedal) radiographs, from age 1 to 11 months

The aim of this study was to monitor the postnatal radiographic development of the proximal and distal double contours and the modelling of the shape of the proximal articular border. In mature horses, the proximal and distal contours of the navicular bone on dorsopalmar dorsoproximal-palmarodistal oblique (upright pedal) radiographs are commonly visualised as 2 lines, one being the articular border and the second representing the border of the cortex facing the deep digital flexor tendon (flexor border). The shape of the proximal articular border may be concave, undulating, straight or convex in the mature animal. These shapes have been found to be hereditary and to constitute a predisposing factor in the pathogenesis of navicular disease. This predisposing role may result from a shape dependent distribution of the biomechanical forces exerted on this region. There is no agreement in the literature with respect to the moment when the navicular bone takes its mature radiographic appearance. Upright pedal radiographs of the left front foot of 19 Dutch Warmblood foals were made at age 1 month and subsequently at intervals of 4 weeks, until the age of 11 months. The distal double contour developed soon after birth and the radiographic visibility of the articular border improved from ill-defined at 1 or 2 months to clear manifestation at 3 or 4 months. The proximal double contour developed later. The articular border became usually visible at age 3 or 4 months and was clearly visible from age 9 months. The mature shape of the proximal articular border usually became recognisable from age 7 months and was always obvious between 9 and 11 months. This development was associated with a gradual modelling of the lateral and medial extremities of the navicular bone. It was concluded that the navicular bone adopts its mature radiological appearance during the first year postpartum. Considering this early manifestation of the mature shape of the proximal articular border and its previously demonstrated inheritance, a force-dependent development of this shape, as predicted by the trajectional theory/Wolffs law, is improbable. The predisposing role of this shape in the pathogenesis of navicular disease may therefore be explained by a shape-dependent distribution of the biomechanical forces exerted on the navicular bone. Considering the potential application of these findings, from age 1 year shape determination enables identification of the individual and breed susceptibility for the development of navicular disease.     

Relationships of age and shape of the navicular bone to the development of navicular disease: a radiological study

Estimating the shape of the proximal articular border of the navicular bone and grading the radiological navicular bone condition (grades 3 and 4 representing the most severe changes), the aim of this study was to assess potential age-related implications of the previously reported shape predisposition to navicular disease in 746 normal and 174 clinically affected Dutch Warmbloods age 3-19 years. A significant, age-independent, shape-grade association found in normal and affected horses emphasises the fundamental character of the shape predisposition to navicular disease. A significant age-related increase of the least susceptible shape prevalence was found in elderly normal horses. A shape-independent low grades 3 and 4 prevalence (mean 15%) was found in normal horses, vs. a high grades 3 and 4 prevalence (mean 85%) in the affected horses. Therefore, the clinical manifestation of the disease is grade-rather than shape-dependent. A significant age-related appearance of inverted flask-shaped channels and enthesophytes was found in the clinically affected horses. However, considering the significant shape-radiological features association previously reported in 3-year-old normal horses, this association may be shape- rather than age-dependent.     

ULTRASONOGRAPHY OF THE EQUINE CRUS

Ultrasonography was used to delineate the sonographic anatomy of the equine crus, emphasizing the peroneus tertius muscle and the Achilles tendon. The cross-sectional gross anatomy was studied in 6 cadaveric limbs. Using a 5.5 MHz mechanical sector scanner the examined Achilles tendon and per- oneus tertius muscle were easily identified as hyperechoic structures in 10 limbs of normal live horses. In 4 lame horses diagnostic ultrasound aided the diagnosis of peroneus tertius rupture, haematoma of the lateral digital extensor muscle and the presence or absence of Achilles tendon injury associated with intertendinous calcaneal bursitis.