Jorge Luis Chacón

Bio: Jorge Luis Chacón is an academic researcher from University of São Paulo. The author has contributed to research in topics: Infectious bronchitis virus & Avian infectious bronchitis. The author has an hindex of 11, co-authored 16 publications receiving 284 citations. Previous affiliations of Jorge Luis Chacón include CEVA Logistics.

Emergence of enteric viruses in production chickens is a concern for avian health.

Abstract: Several viruses have been identified in recent years in the intestinal contents of chickens and turkeys with enteric problems, which have been observed in commercial farms worldwide, including Brazil. Molecular detection of these viruses in Brazil can transform to a big threat for poultry production due to risk for intestinal integrity. This disease is characterized by severely delayed growth, low uniformity, lethargy, watery diarrhea, delayed feed consumption, and a decreased conversion rate. Chicken astrovirus (CAstV), rotavirus, reovirus, chicken parvovirus (ChPV), fowl adenovirus of subgroup I (FAdV-1), and avian nephritis virus (ANV) were investigated using the conventional polymerase chain reaction (PCR) and the reverse transcription polymerase chain reaction (RT-PCR). In addition, the infectious bronchitis virus (IBV), which may play a role in enteric disease, was included. The viruses most frequently detected, either alone or in concomitance with other viruses, were IBV, ANV, rotavirus, and CAstV followed by parvovirus, reovirus, and adenovirus. This study demonstrates the diversity of viruses in Brazilian chicken flocks presenting enteric problems characterized by diarrhea, growth retard, loss weight, and mortality, which reflects the multicausal etiology of this disease.

Epidemiological survey and molecular characterization of avian infectious bronchitis virus in Brazil between 2003 and 2009

Abstract: As part of an epidemiological study of infectious bronchitis virus (IBV) in Brazil, 252 samples from IBV-suspect flocks were tested and the IBV-positive samples were analysed by sequencing of hypervariable regions 1 and 2 of the S1 gene. A high prevalence of IBV variants was found and the sequence analysis of 41 samples revealed a high molecular similarity among the Brazilian isolates (from 90.2 to 100% and from 85.3 to 100% nucleotide and amino acid identity, respectively). The Brazilian isolates showed low genetic relationship with Massachusetts (63.4 to 70.7%), European (45.9 to 75.6%), American (49.3 to 76.4%) and other reference serotypes (67.5 to 78.8%). The Brazilian isolates branched into one unique cluster, separate from the reference serotypes used for infectious bronchitis control in other countries. The variants analysed in this work had a high similarity with all previously published Brazilian IBV isolates, suggesting the presence and high prevalence of a unique or predominant genotype circulating in Brazil. In addition, the virus neutralization test showed that the three Brazilian isolates analysed in the present study are antigenically related to one another but are different from the Massachusetts serotype. The present study shows that IBVs of a unique genotype can be associated with different clinical diseases, and that low genetic variation was detected in this genotype over a long period of time. The molecular characterization of the Brazilian variants isolated from 2003 to 2009 from different geographic regions of the country shows that only one predominant genotype is widespread in the Brazilian territory, denominated in this study as BR-I genotype.

Characterization by restriction fragment length polymorphism and sequence analysis of field and vaccine strains of infectious laryngotracheitis virus involved in severe outbreaks

Abstract: At the end of 2002 and throughout 2003, there was a severe outbreak of infectious laryngotracheitis (ILT) in an intensive production area of commercial hens in the Sao Paulo State of Brazil. ILT virus was isolated from 28 flocks, and 21 isolates were genotyped by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) using four genes and eight restriction enzymes, and by partial sequencing of the infected cell protein 4 (ICP4) and thymidine kinase (TK) genes. Three groups resulted from the combinations of PCR-RFLP patterns: 19 field isolates formed Group I, and the remaining two isolates together with the chicken embryo origin (CEO) vaccine strains formed Group II. Group III comprised the tissue-culture origin (TCO) vaccine strain by itself. The PCR-RFLP results agreed with the sequencing results of two ICP4 gene fragments. The ICP4 gene sequence analysis showed that the 19 field isolates classified into Group I by RFLP-PCR were identical among themselves, but were different to ...

Diseases of Poultry

Abstract: VERY few veterinary surgeons have thought fit to write a book on diseases of poultry. Mr. Ernest Gray has done justice to the subject and is to be congratulated on his effort. A book of this size, written by one with specialized knowledge, will add to the value of any library or private bookshelf. Diseases of Poultry Their Aetiology, Diagnosis, Treatment and Control; with a Section on the Normal Anatomy and Physiology of the Fowl. By Ernest Gray. (Lockwood's Agricultural and Horticultural Handbooks.) Pp. x + 198 + 16 plates. (London: Crosby Lockwood and Son, Ltd., 1940.) 9s. 6d. net.

鳥類の内科学と外科学 : Avian medicine and surgery

Abstract: Section I: The Normal Bird: Systematics. Reproductive Physiology. Nutrition. Laws and Regulations Affecting Aviculture and the Pet Bird Industry. Embryology. Pediatricsand Hand Raising. Behavior. Avicultural Medicine and Flock Health Management. Nonsurgical Methods of Avian Sex Identification. Section II: Diagnostics, Hospital Techniques, And Supportive Care: Physical Examination. Avian Clinical Pathology: Hematologyand Chemistry. Diagnostic Necropsy and Pathology. Radiology. Ultrasonography. Cytology. Differential Diagnostics. Hospital Techniques and Supportive Care. Section III: Infectious Diseases: Bacteriology. Virology. Mycotic Diseases. Parasitology. Zoonotic Diseases. Chlamydia. Mycoplasmal Infections. Section IV: Noninfectious Diseases: Respiratory Disorders. Gastrointestinal Tract. Avian Nervous System. The Endocrine System. Avian Cardiac Disease. Nutritional Disorders. Disorders of the Musculoskeletal System. Avian Dermatology. Disorders of the Special Senses. Neoplasia. Toxicities. Urogenital Disorders. Diseases of the Avian Immune System. Behavioral Problems. Section V: Pharmacology and Therapeutics: Metabolism, Pharmacology, And Therapy. Formulary.

Newcastle disease, other avian paramyxoviruses, and avian metapneumovirus infections

Abstract: The Paramyxoviridae family has several genera that include important human and veterinary pathogens such as Rubulavirus, Respiroviruses, Henipavirus, and the Avulavirus genus that contains Newcastle disease virus (NDV) and other avian paramyxoviruses (APMV). This chapter focuses on infections of poultry with NDV. It offers detailed coverage of the history, etiology, pathobiology, epidemiology, diagnosis, and intervention strategies of Newcastle disease, APMV, and avian Metapneumovirus Infections. AMPV infections continue to emerge as a disease threat with four defined subtypes, A-D, being recognized and producing clinical disease in both turkeys and chickens. For effective disease management, it is important to be able to identify birds that are infected with NDV and distinguish vaccine viruses from virulent viruses. Regardless of whether ND control is applied at the international, national, or farm level, the objective is either to prevent susceptible birds from becoming infected or to reduce the number of susceptible birds by vaccination.