IMAGING CHARACTERISTICS OF INTRATHORACIC HISTIOCYTIC SARCOMA IN DOGS

In this retrospective study, two observers independently reviewed thoracic imaging studies of 39 dogs with confirmed histiocytic sarcoma. The most common findings were intrathoracic lymphadenopathy, identified by the first and second observers in 82.1% and 87.2% of dogs, respectively, and pulmonary masses (74.4% and 82.1%). Right middle lung lobe masses were significantly more common than masses in any other lung lobe (P<0.0013), with the majority having a ventral distribution. Sternal and tracheobronchial lymphadenopathy were significantly more common than cranial mediastinal lymphadenopathy (P‐values of 0.0002 and 0.012, respectively). Interobserver agreement regarding distribution of lymphadenopathy and pulmonary masses was good (κ=0.64 and 0.75, respectively). Other findings included pulmonary nodules, pleural effusion, and abnormal pulmonary patterns. In patients with CT examinations, the majority of masses were mildly to moderately enhancing and heterogeneous, poorly marginated, and bronchocentric. Lymphadenopathy and pulmonary masses are the most common intrathoracic findings in dogs with histiocytic sarcoma, and the strong predilection for the ventral aspect of the right middle lung lube may help to differentiate it from other types of neoplasia.     

Description of the Infection Status in a Norwegian Cattle Herd Naturally Infected by Mycobacterium avium subsp. paratuberculosis

The Norwegian surveillance and control programme for paratuberculosis revealed 8 seroreactors in a single dairy cattle herd that had no clinical signs of Mycobacterium avium subsp. paratuberculosis (M. a. paratuberculosis) infection. Paratuberculosis had been a clinical problem in goats several years previously in this herd. All 45 cattle were culled and a thorough investigation of the infection status was conducted by the use of interferon-γ (IFN-γ) immunoassay, measurement of antibodies, and pathological and bacteriological examination.In the IFN-γ immunoassay, 9 animals gave positive results, and 13 were weakly positive, while 19 animals were negative. In the serological test,10 animals showed positive reactions, and 5 were doubtful, while 30 animals gave negative reactions. There appeared to be a weak trend toward younger animals having raised IFN-γ and older animals having raised serological tests. Histopathological lesions compatible with paratuberculosis were diagnosed in 4 animals aged between 4 and 9 years. Three of these animals had positive serological reaction and one animal gave also positive results in the IFN-γ immunoassay. Infection was confirmed by isolation of M. a. paratuberculosis from 2 of these 4 animals. One single bacterial isolate examined by restriction fragment length polymorphism (RFLP) had the same profile, B-C1, as a strain that had been isolated from a goat at the same farm several years previously.Despite many animals being positive in one or both of the immunological tests, indicative of a heavily infected herd, none of the animals showed clinical signs and only one cow was shown to be shedding bacteria. A cross-reaction with other mycobacteria might have caused some of the immunoreactions in these animals. It is also possible that the Norwegian red cattle breed is resistant to clinical infection with M. a. paratuberculosis.     

A study of cattle infected with Brucella abortus and which showed aberrant serological reactions

SUMMARY Sixty cows, 48 of which had been vaccinated with live Brucella abortus strain 19 (S19) or with killed B. abortus strain 45/20 (S45/20) and 12 of which were unvaccinated animals, were challenged with B. abortus strain 544. Ten of the 27 cattle found to be infected after challenge showed aberrant serological reactions to the Rose Bengal Plate test, serum agglutination test and/or complement fixation test. These 10 cattle were all previously vaccinated with S19 or S45/20. It was concluded that infection in cattle vaccinated with S19 or S45/20 may be more difficult to detect than infection in animals that have no history of vaccination.     

Late pliocene faunal turnover in the turkana basin, kenya and ethiopia

Analysis of a large sample of well-dated fossil mammals from localities in the Turkana Basin of Kenya and Ethiopia revealed sampling biases that affect patterns of faunal turnover during the late Pliocene. When these biases were accounted for, results indicated that 58 to 77 percent of the mammal species were replaced between 3.0 and 1.8 million years ago (Ma). Overall diversity increased from 3.0 to 2.0 Ma but then declined. No distinct turnover pulse is seen between 2.8 and 2.5 Ma; instead, the most significant period of faunal change began after 2.5 Ma and continued through 1.8 Ma.     

Florfenicol in Atlantic salmon, Salmo salar L., parr: tolerance and assessment of efficacy against furunculosis

Abstract. The efficacy of florfenicol against laboratory-induced infection with Aeromonas salmonicida was tested in Atlantic salmon, Salmo salar L., parr. Medication at three dose levels in the feed was started 24 h after bath challenge with A. salmonicida. The specific mortality rate in the unprotected infected control group was 75% compared with 5, 13 and 17% when florfenicol was given at dose levels of 20, 10 and 5 mg per kg body weight per day, respectively. Florfenicol was palatable to the fish at doses in excess of effective therapeutic levels and feeding for 10 days at 100 mg per kg, or for prolonged periods at 50 mg per kg and 10 mg per kg, resulted in no feeding problems or histopathological abnormalities. Florfenicol appears to have a good therapeutic index and considerable potential in the control of furunculosis in salmon.     

MAGNETIC RESONANCE IMAGING APPARENT DIFFUSION COEFFICIENTS FOR HISTOLOGICALLY CONFIRMED INTRACRANIAL LESIONS IN DOGS

Diffusion‐weighted imaging is an advanced magnetic resonance imaging technique that is well established in the diagnosis of nonhemorrhagic infarction in people. However, recent investigations into intracranial neoplastic and inflammatory disease in people have identified variable and overlapping results. In this retrospective study of 37 dogs with histologically confirmed intracranial disease, we investigated whether histogram analysis of quantitative apparent diffusion coefficients (ADC) can differentiate specific disease processes. Disease categories included: meningiomas, glial cell tumors, choroid plexus tumors, pituitary tumors, inflammatory brain diseases, acute nonhemorrhagic infarcts, chronic nonhemorrhagic infarcts, and hemorrhagic infarcts. A wide range of ADC value distributions were identified within the disease groups, and there were overlapping ADC values between most groups. Low ADC values indicating restricted diffusion of water were identified in acute nonhemorrhagic infarcts as expected, but were also seen in meningiomas, glial cell tumors, and granulomatous meningoencephalitis. Based on this preliminary data it is unlikely that singular quantitative ADC values can be used to determine the histological type of canine intracranial disease.