Vertebral Osteomyelitis in Broilers: A Review

Locomotor diseases are still a challenge in modern poultry. Vertebral osteomyelitis (VO) is an emerging disease in broilers worldwide. The inflammatory process in the affected thoracic vertebra (T4) and subsequent spinal cord compression leads to clinical signs related to locomotor impairment, inadequate feeding and drinking, and increased mortality in the affected flocks. The pathogenesis of the disease is poorly understood and Enterococcus cecorum is the bacterium most frequently associated with the disease. However, other bacteria such as E. faecalis, E. durans, Escherichia coli and Staphylococcus aureus have been recently detected in cases of the disease, raising questions regarding its etiopathogenesis. As many questions about VO in broilers remain unanswered, knowledge on its prevention, control and treatment is limited. In this review, we compile and discuss the currently available information concerning VO in broilers and highlight important aspects of the disease.(AU)

Vertebral Osteomyelitis in Broilers: A Review

Locomotor diseases are still a challenge in modern poultry. Vertebral osteomyelitis (VO) is an emerging disease in broilers worldwide. The inflammatory process in the affected thoracic vertebra (T4) and subsequent spinal cord compression leads to clinical signs related to locomotor impairment, inadequate feeding and drinking, and increased mortality in the affected flocks. The pathogenesis of the disease is poorly understood and Enterococcus cecorum is the bacterium most frequently associated with the disease. However, other bacteria such as E. faecalis, E. durans, Escherichia coli and Staphylococcus aureus have been recently detected in cases of the disease, raising questions regarding its etiopathogenesis. As many questions about VO in broilers remain unanswered, knowledge on its prevention, control and treatment is limited. In this review, we compile and discuss the currently available information concerning VO in broilers and highlight important aspects of the disease.

Pathological, immunohistochemical, and molecular findings in commercial laying hens and in backyard chickens naturally infected with the infectious laryngotracheitis virus

Seventy-eight chickens from a very high poultry density (approximately eight million) region and twelve backyard chickens from neighboring areas were analyzed by histopathology and additional techniques for the presence of the infectious laryngotracheitis virus. The virus distribution was determined in different tissues using immunohistochemistry (IHC) and polymerase chain reaction (PCR). The disease was histopathologically diagnosed in 41.0% (32/78) of the commercial layers. Lesions were mainly characterized by syncytial cells with eosinophilic intranuclear inclusion body formed from the hyperplastic epithelium of the upper respiratory tract, primary and secondary bronchi, and conjunctiva. IHC showed 70% (21/30) positive signal in the larynx/trachea and, 53.8% (14/26) in the lungs, either in epithelial cells or syncytia. In the turbinates and paranasal sinuses, 29.6% (8/27) of samples showed positive signal. PCR detected the following gallid herpesvirus 1-positive percentages: conjunctiva 63.2% (31/49), lungs 57.6% (30/52), turbinates and paranasal sinuses 56% (28/50), and larynx/trachea 50% (39/78). IHC showed to be a useful additional tool for definitive ILT diagnosis, especially during the subacute phase of the disease when syncytial cells with intranuclear inclusion bodies are no longer observed. PCR using specific primers from ICP4 gene, generating a product of 237 base pairs, was sensitive for ILT diagnosis, and very useful for rapid detection of GaHV-1 in chickens. Fixed tissues allowing histopatological examination and detection of GaHV-1 by PCR, are a good option in areas where farms are located several hundred kilometers away from a diagnostic center, reducing problems with conservation of fresh samples and the risk of virus spread.

Pathological, immunohistochemical, and molecular findings in commercial laying hens and in backyard chickens naturally infected with the infectious laryngotracheitis virus

Seventy-eight chickens from a very high poultry density (approximately eight million) region and twelve backyard chickens from neighboring areas were analyzed by histopathology and additional techniques for the presence of the infectious laryngotracheitis virus. The virus distribution was determined in different tissues using immunohistochemistry (IHC) and polymerase chain reaction (PCR). The disease was histopathologically diagnosed in 41.0% (32/78) of the commercial layers. Lesions were mainly characterized by syncytial cells with eosinophilic intranuclear inclusion body formed from the hyperplastic epithelium of the upper respiratory tract, primary and secondary bronchi, and conjunctiva. IHC showed 70% (21/30) positive signal in the larynx/trachea and, 53.8% (14/26) in the lungs, either in epithelial cells or syncytia. In the turbinates and paranasal sinuses, 29.6% (8/27) of samples showed positive signal. PCR detected the following gallid herpesvirus 1-positive percentages: conjunctiva 63.2% (31/49), lungs 57.6% (30/52), turbinates and paranasal sinuses 56% (28/50), and larynx/trachea 50% (39/78). IHC showed to be a useful additional tool for definitive ILT diagnosis, especially during the subacute phase of the disease when syncytial cells with intranuclear inclusion bodies are no longer observed. PCR using specific primers from ICP4 gene, generating a product of 237 base pairs, was sensitive for ILT diagnosis, and very useful for rapid detection of GaHV-1 in chickens. Fixed tissues allowing histopatological examination and detection of GaHV-1 by PCR, are a good option in areas where farms are located several hundred kilometers away from a diagnostic center, reducing problems with conservation of fresh samples and the risk of virus spread.(AU)

Soroprevalência de pseudorraiva, peste suína clássica e brucelose em suínos do estado do Piauí / Seroprevalence of pseudorabies, classical swine fever and brucellosis in swine in the state of Piauí

Este trabalho teve como objetivo determinar a soroprevalência de pseudorraiva, peste suína clássica (PSC) e brucelose suína em suínos do estado do Piauí, Brasil. Foram coletadas amostras sanguíneas de 384 suínos de criações intensivas e extensivas do estado. Anticorpos anti-Brucella spp. foram detectados pelo teste do antígeno acidificado tamponado e confirmados pelo teste 2-mercaptoetanol, enquanto a detecção de anticorpos contra os vírus da PSC e pseudorraiva foi realizada por ensaio imunoenzimático (ELISA), utilizando-se kits comerciais específicos. Anticorpos anti-Brucella spp. foram detectados em 1,04% (2/192) dos suínos de criações intensivas. Dos rebanhos avaliados, 0,78% (3/384) dos animais exibiram anticorpos contra o vírus da PSC, sendo 1,04% (2/192) de criações intensivas e 0,52% (1/192) de criações extensivas. Anticorpos contra o vírus da pseudorraiva foram detectados apenas em suínos de criação extensiva, com prevalência de 5,2% (10/192). Esses são os primeiros dados sobre a soroprevalência da brucelose suína, pseudorraiva e PSC em rebanhos do Piauí. A detecção de 10 amostras positivas para pseudorraiva causa preocupação sobre a possibilidade da circulação viral na população suídea desse estado e revela uma necessidade premente de realização de estudos mais extensos para melhor compreender a importância dessas enfermidades de notificação obrigatória em estados da região Nordeste brasileira.(AU)

This study aimed to determine the prevalence of Pseudorabies, Classical Swine Fever (CSF) and Swine Brucellosis in swine in the state of Piauí, Brazil. Blood samples were collected from 384 pigs from intensive and small outdoor systems in the state. Anti-Brucella spp. antibodies were detected by Buffered Acidified Antigen Test and positive results confirmed by 2-Mercaptoethanol Test. Detection of antibodies against CSF and Pseudorabies virus were performed by Enzyme-Linked Immunosorbent Assay (ELISA) using specific commercial kits. Only two samples (1.04% - 2/192) from the intensive system were seropositive to Brucella spp. In the evaluated herds, 0.78% (3/384) of animals had antibodies against CSF virus, two from outdoor pigs (1.04% - 2/192) and one from intensive systems (0.52% - 1/192). Antibodies against the Pseudorabies virus were detected only in outdoor pigs, with seroprevalence of 5.2% (10/192). This is the first report on seroprevalence of Pseudorabies, CSF and Brucellosis in hog farms in Piauí, Brazil. The detection of 10 positive cases raises a concern regarding Pseudorabies virus circulation in the swine population in the state and reveals a need for further studies to better understand the real situation and status of obligatory notified diseases in the swine herds in the Northestern states of Brazil.(AU)