Comparison of adjuvants with respect to serum IgG antibody response in orally immunized chickens

We have previously shown that oral immunization with non-replicating antigens hardly induced serum IgG antibody response in chickens and addition of sodium fluoride (NaF) to the immunogen markedly improved their immunological states. In the present study, taurine, lithium and Quillaja saponin (Q-SAP) were compared with NaF with respect to their enhancement of serum IgG antibody response in chickens after oral immunization. The antibody titer of chickens which received Q-SAP as the mucosal adjuvant tended to be higher than that of chickens which received antigen plus NaF. Simultaneous administration of antigen with lithium or taurine elicited a higher antibody titer in chickens compared to those of chickens orally immunized with antigen alone, but the effect of these two adjuvants was less efficient compared with that of NaF. These results suggested that Q-SAP as well as NaF is useful as an oral adjuvant for chickens.     

Search for Climatic Models for Forecasting Microtine Outbreaks1

Models for forecasting outbreaks of harmful Microtines are discussed in terms of the three most important types of rodent damage to agriculture and forestry in the European part of EPPO region: problems to field crops by Microtus arvalis and related species, to horticulture and forestry by M. agrestis and some other species, and injury to the underground parts of various crops by Arvicola terrestris. Two models were developed in parallel but independently for M. arvalis, one in the USSR, the other in France; the former approach included M. socialis. A joint Scandinavian project resulted in models for M, agrestis and Clethrionomys glareolus: the outcome is exemplified by the former case and a few comments are given on other types of model development. The probable mechanism of climatic influence through the food chain on the population dynamics of Microtine rodents is discussed and it is concluded that climatic models are a useful tool in planning rodent control strategies. The role of the EPPO Working Party on Field Rodents as a coordinating body in the development of rodent forecasts is also reviewed.     

POSITRON EMISSION TOMOGRAPHY FEATURES OF CANINE NECROTIZING MENINGOENCEPHALITIS

A Yorkshire terrier and a Chihuahua were referred for acute onset, generalized tonic‐clonic seizures and were suspected to have meningoencephalitis based on magnetic resonance (MR) imaging findings. Brain lesions appeared hyperintense with T2‐weighted imaging and hypointense with T1‐weighted imaging, and were characteristic of necrotizing meningoencephalitis. Both dogs were diagnosed with necrotizing meningoencephalitis based on pathologic findings. Fluorine‐18 fluorodeoxyglucose positron emission tomography (FDG‐PET) was performed on both animals before euthanasia with the permission of the owner. In FDG‐PET images, these lesions seen in MR images were characterized by multifocal or diffuse hypometabolism. Our FDG‐PET results provided evidence of glucose hypometabolism in areas of necrosis and cavitation associated with necrotizing meningoencephalitis. FDG‐PET has the potential to provide valuable diagnostic information in dogs with suspected necrotizing encephalitis.     

Analysis of tidal breathing flow volume loop in dogs with tracheal masses

Objectives To investigate whether there are any changes in the tidal breathing flow volume loop (TBFVL) in calm, non-dyspnoeic dogs with intratracheal masses. Methods We compared 4 dogs with intratracheal masses (group 1) with 10 healthy dogs (group 2). Routine clinical and laboratory examinations of the dogs were unremarkable, except for episodic upper respiratory obstructive signs in the dogs in group 1. Lateral radiography of the neck and thorax showed that group 1 dogs had masses that appeared to protrude into the tracheal lumen. Tracheoscopy and surgery or necropsy was performed to confirm the presence of the mass. Arterial blood gas and TBFVL analysis was carried out in all dogs to assess respiratory status. Results The shape of the TBFVL for dogs in group 1 was narrower and ovoid compared with that for the group 2 dogs. Tidal volume and expiratory and inspiratory times were significantly reduced, whereas the respiratory rate was increased for dogs in group 1 compared with dogs in group 2. Arterial blood gas analysis was unremarkable for all dogs. Conclusions TBFVL is a non-invasive technique that is easy to perform and well tolerated by dogs. In the absence of abnormalities detected by routine diagnostic evaluations and arterial blood gas analysis in dogs with intratracheal masses, the TBFVL contributes to the definition of the physiologic status of the airways at the time of testing, and results suggests that these dogs breathe quite normally when they are calm and non-dyspnoeic.     

Acute hepatitis in a piglet experimentally inoculated with tissue homogenates from pigs with postweaning multisystemic wasting syndrome

Five 2 day-old colostrum-deprived piglets were inoculated with tissue homogenates from pigs with postweaning multisystemic wasting syndrome. One of the five piglets developed icterus and died 23 days post-inoculation. Histologic examination revealed acute hepatitis. Porcine circovirus type 2 (PCV-2) antigen and nucleic acid were detected in hepatocytes and phagocytic cells. Ultrastructurally, hepatocytes and phagocytic cells had large numbers of cytoplasmic inclusions, which were composed of electron-dense paracrystalline arrays of small non-enveloped viral particles approximately 17 nm in diameter. Apoptotic hepatocytes were confirmed by the TUNEL method and electron microscopic examination. These findings may indicate that hepatocellular necrosis is associated with replication of PCV-2. Apoptosis of hepatocytes also contributes to the pathogenesis of hepatic lesions in this case.