Calnek, B. W.. Overview . Enfermedades de las aves by B. W Calnek(Book) 2 editions Salt poisoning in 5 day old turkey poults by B. W Calnek() 1 edition. Bruce W. Calnek. American Artículo histórico- Revista Avian Diseases ( Enfermedades de las Aves): la creación y evolución del legado de P. Philip Levine. Las infecciones por adenovirus son ubicuas entre las aves de explotación comercial Estas enfermedades son de importancia menor en lo que a salud pública se refiere. . Diseases of poultry, 10th Ed. (B.W. Calnek with H.J. Barnes, .

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Among the anatomopathological characteristics enfemredades mild cases of respiratory disease are excessive mucus, which can even become sebaceous —especially in broilers— and pulmonary congestion and opacity, with engrossed air sac walls. Zollman; also letters from several of the speakers to Dr. Evolution of avian infectious bronchitis virus: Cavanagh D, Naqi S. Scheidy, William Wagner, and Paul E. Received in November, Breadth of protection of the respiratory tract provided by different live-attenuated infectious bronchitis vaccines avfs challenge with infectious bronchitis viruses of heterologous serotypes.


In the case of Cuba, the results suggest that other, yet to be studied variants or serotypes of the Massachusetts strain may be currently circulating. Can J Vet Res. Serotyping is done using hemagglutination inhibition assays, employing ELISA instead for serological diagnosis. Longitudinal field studies of infectious bronchitis virus and avian pneumovirus in broilers using type-specific polymerase chain reactions. Most of them, however, are prone to zves the disease themselves, and the protection they provide is poor or nil [34], as reported in for the DE [35, 36] and GA98 [37, 38] variants in the USA.

Molecular epidemiology of avian infectious bronchitis in Brazil from to in breeders, broilers, and layers. RESULTS The main histological changes in paranasal sinuses, trachea and lungs of laying hens, grouped according to their score in classification scheme used during gross examinations, are shown in the table.

Some of the most conspicuous findings include the erosion of the epithelium with degenerative damage of paranasal sinus glands, BALT hyperplasia, and glandular hyperplasia with mucus hypersecretion throughout the respiratory epithelium with loss of cilia paranasal sinuses, trachea and primary bronchi. Identification and analysis of the Georgia 98 serotype, a new serotype of infectious bronchitis virus. Antigenic and S-1 genomic characterization of the Enfermeddades variant serotype of infectious bronchitis virus.


Calnek, B. W.

During mild respiratory infections it is common to detect renal alterations such as inflammation and discoloration of kidneys, presence of urate salts at the ureters urolithiasis and visceral gout. Infectious bronchitis enfedmedades field vaccination coverage and persistence of Arkansas-type viruses in commercial broilers. Anderson, Alan Bachrach, W.

Many different IBV vaccines -mostly against variants of the Massachusetts strain- have been developed internationally, and their efficacy in broilers and laying hens has been well studied. A history of avian medicine at Cornell University by B. Another important histopathological finding is the presence of hyperplastic acinotubular glands.

Enfermedades de las aves – B. W. Calnek – Google Books

Some of these variants are indigenous, while others enfermedaades genetically related to IBV variants in neighboring countries [47], suggesting that IBV strains in Korea are evolving continuously [49].

IBV is a highly infectious efermedades with a geographic distribution spanning the entire world. One prominent example of the latter case is that of avian infectious bronchitis virus IBVa gammacoronavirus belonging to the Coronaviridae family, in the order Nidovirales [3]. Epidemiology of infectious bronchitis virus in Belgian broilers: The latter avse alterations, specifically those in the trachea, are defense mechanisms due to ciliary movement and the exudation of mucus by goblet cells during IBV infection [26].

There were statistically significant differences regarding the degree of epithelial gland loss in the tracheal rings of groups exhibiting the clinical-pathological alterations of chronic respiratory disease when compared to the control group, which had no apparent alterations.

Variants of the Massachusetts strains were also reported in Chile during the s [42], while the Dutch serotypes D, D, D and D have been described in Europe [43]. Characterisation of strains of infectious bronchitis virus isolated in Chile. Subepithelial engrossment zones are characterized by edema and infiltration of the lamina, mainly by monocytes and lymphocytes [10].


Histologically, there is epithelial hyperplasia and metaplasia, as well as loss of cilia, in both trachea and bronchi, and superficial cells are often engrossed.

They were fed a balanced diet, and their handling complied with current technical guidelines and regulations of the country, in force since the decade of the s [20]. When clinical signs are present, the progression of lesions in this system is divided in three stages: Salt poisoning in 5 day old turkey poults by B. For the above reasons, it was decided to examine the histopathological changes caused by infections of the avian bronchitis virus in vaccinated egg-laying hens affected by chronic respiratory syndrome.

In Cuba there are immunization programs against avian infectious bronchitis based on the application of live and inactivated vaccines in breeder and layer flocks, respectively [18, 19].

ABSTRACT In order to dissect the histopathological changes produced by the infection of avian infectious bronchitis virus in previously vaccinated egg-laying hens from a poultry farming unit, 35 White Leghorn egg-laying hens that had been in production for 9 to 10 months twenty seven of which had clinical symptoms corresponding to respiratory disease and eight apparently healthy individuals were selected for further study.

W Calnek 1 edition published in in English and held by 1 WorldCat member library worldwide. Control of IBV in many countries is achieved mainly through a combination of biosafety procedures and live or inactivated vaccines conferring a specific immune response [17].

The third group severe exhibited the highest pathological significance Figure 4.

Another possible cause is the movement of flocks and the mixing of layer zves batches, which together propitiate coinfections by unrelated strains and thus, the occurrence of recombination events between separate IBV lineages.

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