Radiographic and computed tomographic appearance of tracheal collapse with axial rotation in four dogs

Tracheal collapse with axial rotation was diagnosed in four dogs. Radiographs showed increased tracheal dorsoventral height at the caudal cervical and thoracic inlet with and apparent intraluminal soft tissue opacity, mimicking an intraluminal tracheal foreign body. Computed tomography confirmed dorsoventral tracheal collapse with axial rotation in all dogs. Short‐term outcome with medical treatment of all dogs was excellent.     

羊伪结核病病原的分离鉴定

从不同羊场的山羊颈部淋巴结脓肿处分离到5株革兰氏阳性、无荚膜、无芽胞的多型性球杆菌,其对青霉素等药物有很强的抗药性,对强力霉素高敏.根据其形态学、培养特性、生化特性及致病性试验、动物回归试验和血清学试验结果,判定所分离的5株菌为伪结核棒状杆菌.     

Prevalence of caseous lymphadenitis and usage of caseous lymphadenitis vaccines in sheep flocks

OBJECTIVE: To estimate the prevalence of caseous lymphadenitis (CLA), determine the current usage of vaccines against CLA and to measure the effectiveness of these vaccines on sheep farms. DESIGN AND POPULATION: A survey was undertaken on 223 sheep flocks in New South Wales, Victoria and Western Australia. METHOD: The prevalence of CLA was measured by conventional inspection techniques at abattoirs in lines of sheep that could be traced back to a farm. Managers of the flocks were sent a questionnaire about their vaccine practices, management practices and knowledge of CLA. RESULTS: The average prevalence of CLA in adult sheep in these flocks was 26% and varied from 20% in Western Australia to 29% in New South Wales. About 43% of sheep producers used CLA vaccines; only 12% used them as recommended. Awareness of CLA was highest in Western Australia. More producers would use CLA vaccine if they knew the prevalence of CLA in their flock and producers obtained most information about CLA from vaccine resellers. CONCLUSIONS: Only 10 to 15% of producers are currently achieving effective CLA control through the use of recommended CLA vaccination programs. In Western Australian flocks more than 25% of effectively vaccinated ewes will be sent to abattoirs in the 2 to 3 years after this study. However, large decreases in the prevalence of CLA can be achieved by about 70% of producers by either making adjustments to their vaccination programs or buying a vaccine with a CLA component. Two or three key facts on effective CLA vaccination could be made available at the point of sale of vaccines and from abattoirs that reported the prevalence of CLA to farmers.     

Evaluation of the risk factors influencing the spread of caseous lymphadenitis in goat herds

Epidemiological studies on caseous lymphadenitis were carried out in Poland in 1996 and 2002 among goat herds covered by a milk recording program. Between-herd seroprevalence was 13.2% in 1996 and increased to 62.5% in 2002. The average size of seropositive herds was statistically significantly higher than that of seronegative ones, however there was no statistically significant difference in the age between the herds. A statistically significant prevalence ratio (PR) was identified and relevant attributable risk for exposed animals (AR(exp)) was calculated for the following risk factors: presence of seropositive males in a herd (PR = 8.350; AR(exp) = 0.651), presence of superficial abscesses in animals (PR = 6.142; AR(exp) = 0.620), presence of respiratory signs (PR = 2.900; AR(exp) = 0.393), presence of animals in poor condition in a herd (PR = 2.774; AR(exp) = 0.390) and occurrence of reproductive failures in a herd (PR = 1.798; AR(exp) = 0.230). Purchase of animals from abroad, mastitis and husbandry conditions (housing system, grazing system, hygienic conditions) were not shown to be statistically significant risk factors.     

Pathogenesis of caseous lymphadenitis in sheep and goats

The progress of caseous lymphadenitis in sheep and goats is described as involving primary wound infection, lymphatic and haematogenous dissemination, and secondary infection of lymph nodes and various visceral organs. This is followed by elimination or containment of infection, the latter being represented by the characteristic caseous lesions. Resistance to infection is complex involving components of both the specific and non-specific host response. The role of these in pathogenesis is discussed. Bacterial factors including the phospholipase exotoxin and cytotoxic lipid contribute to pathogenesis at a local level with little likelihood of systemic effect in the natural disease. In a disease such as caseous lymphadenitis, lesion site, size or number do not indicate severity of disease but rather, reflect the ability of the host to mount a cellular response to infection.     

Hereditary xanthinuria in a goat

A 2‐year‐old mixed breed goat was presented for a 1‐day history of anorexia and 1 week of weight loss. Serum biochemistry disclosed severe azotemia. Abdominal ultrasound examination showed decreased renal corticomedullary distinction, poor visualization of the renal pelves, and dilated ureters. On necropsy, the kidneys were small, the pelves were dilated, and the medulla was partially effaced by variably sized yellow nephroliths. Histologically, cortical and medullary tubules were distended by yellow‐brown, multilayered crystals. Stone composition was 100% xanthine. Exonic sequencing of xanthine dehydrogenase (XDH) and molybdenum cofactor sulfurase (MOCOS) identified 2 putative pathogenic variants: a heterozygous XDH p.Leu128Pro variant and a homozygous MOCOS p.Asp303Gly variant. Variant frequencies were determined in 7 herd mates, 12 goats undergoing necropsy, and 443 goats from genome databases. The XDH variant was not present in any of these 462 goats. The MOCOS variant allele frequency was 0.03 overall, with 3 homozygotes detected. Hereditary xanthinuria is a recessive disorder in other species, but the XDH variant could be causal if the case goat is a compound heterozygote harboring a second variant in a regulatory region not analyzed or if the combination of the XDH and MOCOS variants together abolish XDH activity. Alternatively, the MOCOS variant alone could be causal despite the presence of other homozygotes, because hereditary xanthinuria in humans often is asymptomatic. Ours is the first report describing the clinical presentation and pathology associated with xanthine urolithiasis in a goat. The data support hereditary xanthinuria, but functional studies are needed to conclusively determine the causal variant(s).     

A field trial to evaluate a whole cell vaccine for the prevention of caseous lymphadenitis in sheep and goat flocks.

A field trial to evaluate a whole cell vaccine for the prevention of caseous lymphadenitis (CLA) in sheep and goats was performed in one goat herd and one sheep flock over a period of three years. In goats, there was a nonstatistically significant trend for fewer cases of CLA in the vaccinated animals compared to the controls. In sheep, from six months to 36 months postinitial vaccination, the proportion of vaccinated sheep that developed CLA was significantly less (p less than 0.05) than in the control sheep. The antibody titers to Corynebacterium pseudotuberculosis as detected by microagglutination assay were significantly different (p less than 0.0001) at all times except at the initial vaccination. Swellings occurred at the vaccination site at an incidence level of 29.6% in goats and 34.1% in sheep. The vaccine appeared to be efficacious in reducing the proportion of sheep that developed CLA when challenged naturally in a field situation.     

Prevalence and distribution of caseous lymphadenitis in feral goats

A total of 2,920 feral goats from pastoral areas of Western Australia were examined and the prevalence of caseous lymphadenitis was estimated to be 7.8 +/- 0.9% in goats presented for slaughter. Head, body and visceral lesions were present in 49.3%, 46.7% and 12.3% of affected goats, respectively. A comparison with previously reported data from sheep has been made and significant differences are discussed. Lung lesions were relatively uncommon in goats, whereas the distribution of carcase lesions was similar between the species. Multiple lesions appear to be less common in goats than in sheep.     

High seroprevalence of caseous lymphadenitis in Brazilian goat herds revealed by Corynebacterium pseudotuberculosis secreted proteins-based ELISA

We conducted a seroepidemiological survey to determine the prevalence of caseous lymphadenitis (CLA) in goat herds in Minas Gerais state, Brazil. Serum samples were collected from goats (n = 676) from 108 rural properties in 2001, covering most of the sub-regions of this ca. 586,500 square kilometer state. Antibodies against Corynebacterium pseudotuberculosis secreted proteins were detected by an indirect enzyme-linked immunosorbent assay (ELISA). Most of the animals (78.9%) tested positive for CLA; 98% of flocks presented at least one seropositive animal. Goats managed under an extensive production system had a significantly higher seroprevalence of CLA than those in intensive and semi-intensive operations. The age distribution of the animals in the flocks affected the prevalence of this disease; however, goat breed did not. We found seropositivity against C. pseudotuberculosis to be highly prevalent in these Brazilian goat herds; consequently, appropriate management practices for the control of CLA should be implemented.     

Radiographic and computed tomographic evaluation of experimentally induced lung aspiration sites in dogs

This study was performed to radiographically examine the prevalence of aspiration sites and to evaluate their atomical correlation with the bronchial pattens. Ten healthy beagle dogs were repeatedly radiographed, at weekly intervals, in the left and right lateral, ventrodorsal (VD) and dorsoventral (DV) positions. Three mililiters of iohexol distilled with same volume of saline was infused into the tracheal inlet. Which lung lobe was aspirated was decided upon by the presence of a significant alveolar pattern due to the contrast medium. Alveolar patterns were identified at the left (100%) and right cranial lung lobes (77%) with the dogs in dependant lateral recumbency, at the right caudal lung lobe (71%) with the dogs in VD recumbency and at the right middle lung lobe (59%) with the dogs in DV recumbency, respectively. The anatomical correlation was evaluated by performing computed tomography. The right principal bronchus (165.8 ± 1.6°) was more straightly bifurcated than was the left principal bronchus (142.7 ± 1.8°, p < 0.01). In VD position, the right side lung had a greater opertunity to become aspirated. The ventrally positioned right middle lobar bronchial origin was more easily to be aspirated the other laterally positioned ones. We think that these anatomical characteristics can be one of the causes for aspiration pneumonia to occur more frequently in the right side lung.     

Radiographic,ultrasonographic, and computed tomographic characteristics of an accessory liver lobe in a cat

A 5‐year‐old male Norwegian Forest cat presented with increased hepatic serum biochemical parameters. Abdominal radiography showed an oval cranioventral mass and ultrasound revealed a mobile mass attached to one hepatic lobe. Computed tomography (CT) confirmed that the mass was attached to the right medial liver lobe. Differential diagnoses were an accessory liver lobe, benign neoplasia, and focal nodular hyperplasia. The mass was removed and histopathology confirmed the mass to be normal liver tissue. Accessory liver lobe should be included in the differential diagnosis of a mobile cranial abdominal mass with a similar ultrasonographic or CT appearance to the liver.     

Corynebacterium pseudotuberculosis infection in goats. II. The prevalence of caseous lymphadenitis in 36 goat herds in Northern Norway

The precalen-ce of caseous lymphadenitis was surveyed in 36 goat herds in Northern Norway. In each herd, information concerning the occurrence of the disease was obtained from the farmer. Adult animals (1 year of age or older) in 35 herds were examined for superficial swellings, and serum samples were collected from most animals in the herds. The sera were examined for antibodies to Corynebacterium pseudotuber-culosis using the bacterial agglutination test (BAT) and the hemolysis inhibition test (HIT).Gaseous lymphadenitis was diagnosed with certainty in 19 herds. Information from the farmers indicated that the disease indeed oc-curred in these herds, and that the majority had been infected with the disease for many years. The herds had apparently become infected through contact with animals from infected herds. Clinical examina-tions were carried out in 18 of these herds and superficial swellings were found in 26 % of the examined animals. The prevalence of ani-mals with lesions varied from 11 to 40 % among the herds. Of the animals in these herds, 81 % were positive in BAT and 84 % in HIT. The prevalence of positive animals varied from 26 to 99 % in BAT and 28 to 99 % in HIT. The prevalence of seropositive animals was lowest in a herd in which animals were kept separately in stalls.Caseous lymphadenitis could not be diagnosed in 16 herds. In-formation from the farmers indicated that the disease indeed seemed to be absent in 14 of these herds. These 14 herds had no history of contact with animals from herds considered to be infected. However, in the remaining 2 herds, the farmers were somewhat uncertain about the occurrence of the disease. One of these 2 herds had a history of contact with infected herds through participation in a goat “breeding circle”. Only a few of the animals were, however, seropositive and all these had low antibody titres.In 1 newly established herd, a single animal showed a high posi-tive titre in BAT only. All the other animals were negative in both tests. This particular herd consisted of animals obtained both from herds with caseous lymphadenitis and from herds in which the disease was not considered to occur.     

Characterization of lectin-binding lymphocytes in goats with caseous lymphadenitis

Numbers of lymphoid cells bearing markers for peanut agglutinin, wheat germ agglutinin, and anti-immunoglobulin G in healthy goats and in goats with caseous lymphadenitis were determined by use of immunofluorescent techniques. Results indicated that, when compared with healthy goats, diseased goats had normal numbers of anti-immunoglobulin G-positive cells (B cells), had significantly reduced numbers of peanut agglutinin-positive cells (T cells), and had fewer cells with receptor sites for Lens culinaris agglutinin and concanavalin A. Compared with healthy goats, numbers of peanut agglutinin-positive cells in goats with caseous lymphadenitis indicated that the goats may have had a compromised cell-mediated immunity.     

Abscesses and caseous lymphadenitis in goats in tropical semi-arid north-east Brazil

Summary This study reports the incidence of abscesses in relation toCorynebacterium pseudotuberculosis infection in goats in north-east Brazil. Among 656 goats examined periodically over almost two years 41·6% were found with superficially palpable abscesses. Most of the infected areas were in the anterior half of the body in front of the pre-scapular region; the inguinal region formed the other prominent area. Among 486 dead or slaughtered goats, 56 (11·5%) revealed abscesses in the internal organs. Lungs and epididymis were affected most, liver, spleen, udder and lateropharyngeal nodes were next in order and kidneys and mediastinal nodes were least affected. Thus the overall incidence of external and internal abscesses was 28·8%; of all the abscesses 27·7% were due toC. pseudotuberculosis and the rest due to infections ofCorynebacterium pyogenes and several species of streptococci or staphylococci. The growth ofC. pseudotuberculosis-infected and non-infected goats was of the same order and it seems that caseous lymphadentitis is not the cause of much financial loss in north-east Brazil but in view of its high incidence remedial measures should be considered necessary in regions where the goat meat industry is likely to become more intensive and important.

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Resumen Este estudio informa sobre la incidencia de abscesos en cabras del nordeste de Brasil. Se examinaron 656 cabras periódicamente durante dos a?os, de las cuales 41·6% se encontraron con abscesos superficiales palpables. Las áreas infectadas correspondieron a la mitad anterior del cuerpo, frente a la región pre-escapular y a la región inguinal. De 486 cabras muertas o faenadas, 56 (11·5%) revelaron abscesos en los órganos internos. De estos, los mas afectados, en orden descendente fueron: pulmones, epididimos, hígado, bazo, ubre, nódulos linfáticos faríngeos, ri?ones y nódulos linfáticos mediastínicos. La incidencia general de abscesos externos e internos fue de 28·8%. De todos los abscesos 27·7% se debieron aCorynebacterium pseudotuberculosis y el resto aC. pyogenes y a especies deStreptococcus y Staphylococcus. El crecimiento de cabras infectadas y no infectadas conC. pseudotuberculosis fue similar, lo que sugiere que la linfadenitis caseosa no ocasiona muchas pérdidas económicas en el nordeste de Brasil pero en vista de su alta incidencia medidas de control deben ser consideradas en regiones donde la industria de carne caprina pueda llegar a ser mas intensiva e importance.

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Résumé Parmi 656 caprins examinés périodiquement pendant presque deux ans, 41,6 p. 100 ontété trouvés porteurs d'abcès palpables superficiels. Dans la plupart des cas, la zone infectée se trouvait dans la moitié antérieure du corps, à l'avant de la région pré-scapulaire. La région inguinale constituait la deuxième zone la plus infectée. Sur 486 animaux morts ou abattus 56 (11,5 p. 100) ont montré des abcès internes affectant en premier lieu les poumons et l'épididyme. Le foie, la rate la vessie, les ganglions pharyngienslatéraux venaient ensuite dans l'ordre. Les ganglions rénaux et médiastinaux étaient les moins affectés. La incidence des abcesses externes et internes a étè de 28,8 p. 100. Globalement, 27,7 p. 100 des abcès étaient dus àC. pseudotuberculosis. le reste àC. pyogenes et à quelques espèces de staphylocoques et streptocoques. la croissance des caprins infectés ou non parC. pseudotuberculosis était à peu près identique et il semble que la lymphadénite caséeuse n'entra?ne pas beaucoup de pertes financières dans le Nord-Est brésilien mais étant donné sa fréquence élevée, des mesures curatives devraient être considérées comme nécessaires dans les régions où l'industrie de la viande de chèvre a des chances de devenir plus intensive et plus importante.

     

Radiographic, computed tomographic, and arthroscopic evaluation of experimental radio-ulnar incongruence in the dog

Objective— To compare the diagnostic value of arthroscopy, computed tomography (CT), and radiography for evaluation of radio-ulnar incongruence (RUI).
Study Design— Experimental evaluation of induced progressive RUI.
Sample Population— Cadaveric Labrador forelimbs (n=11).
Methods— The radius was shortened by 1, 2, and 3 mm with a surgical model of RUI. RUI was scored on radiographs, CT (2 radiologists), and arthroscopy (2 surgeons) before and after each modification. The sensitivity and specificity of each modality were compared. The effects of arthroscope and elbow position on arthroscopy observations were evaluated. Agreement between surgeons, radiologists, and each imaging technique and the known status of the elbow was calculated.
Results— Complete arthroscopic sessions had an averaged sensitivity of 94% and specificity of 81.9%. The ability to detect mild incongruity (1 mm step) was greater at the incisure than other locations ( P <.001). The average sensitivity and specificity of radiography were 99.3% and 42.4%, and for CT were 85.05% and 45.8%, respectively. The average agreement between imaging techniques and the known status of the elbows was greater with complete arthroscopic sessions (89.75%) than radiography (70.1%) and CT (76.85%). Inter-investigator agreement was greater between surgeons scoring arthroscopic examinations (88.6%) than radiologists scoring CT studies (43.9%).
Conclusions— Evaluation of arthroscopic images allows sensitive and reproducible detection of experimental RUI, especially at the incisure. Arthroscopic evaluation of experimental RUI reached a higher diagnostic value than radiographs and CT images, because of its specificity and reproducibility.
Clinical Relevance— The diagnostic value and reproducibility of arthroscopy may compare favorably with those of CT when evaluating RUI in dogs with elbow disease.