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)

Health assessment of raptors in triage in Belo Horizonte, MG, Brazil

Falconiformes (n=82), Strigiformes (n=84) and Cathartiformes (n=14) at a triage center (CETAS-Belo Horizonte, IBAMA, Brazil) were examined between 2008 and 2010 . No bird was reactive at hemagglutination-inhibition (HI) for antibodies against Mycoplasma gallisepticum (Mg). Two Caracara plancus (2/68) had HI titers (16-32) against Newcastle disease virus. No Chlamydophila psittaci DNA was detected in the liver (PCR; n=95). Blood smears (Giemsa; n=89) and spleen fragments (PCR; n=82) were 13.5% and 8.5% positive, respectively, for Haemoproteus only. Necropsy of Cathartiformes (n=10), Falconiformes (n=42) and Strigiformes (n=57) showed that trauma injuries were the main cause (63.3%) of admission and death, being fractures (38.5%) of the thoracic limbs (57.1%) the most frequent. Nematode (12.8%), cestode (1.8%), trematode (0.9%), and acanthocephalan (2.7%) parasite infections were relevant. Mites (Acari) were the most frequent (17.4%) external parasites, particularly Ornithonyssus sylviarum in Asio clamator and Amblyomma cajennense in Tyto alba. Chewing lice (10.1%) and Pseudolynchia spp. (9.2%) were also found. Histomonas spp. (6.4%) was found in the ceca of Bubo virginianus, Athene cunicularia, Tyto alba, and Asio clamator, but not in Falconiformes or Cathartiformes. Trichomonas spp. (oral cavity, pharynx and upper esophagus; 9.1%) was detected in Falconiformes and Strigiformes, but not in Cathartiformes. Trichomonas spp. were found in A. cunicularia, Asio clamator, Glaucidium brasilianum and Tyto alba (Strigiformes), and in Rupornis magnirostris, Milvago chimachima, Falco femoralis, Falco sparverius and Caracara plancus (Falconiformes). Coccidia (9.1%) (Sarcocystis spp., 6.4%) and mycosis were observed in most Tyto alba (70%). The evaluated Orders may not pose risks for commercial poultry production. Habitat loss and urban adaptation may be increasingly affecting raptors.

Health assessment of raptors in triage in Belo Horizonte, MG, Brazil

Falconiformes (n=82), Strigiformes (n=84) and Cathartiformes (n=14) at a triage center (CETAS-Belo Horizonte, IBAMA, Brazil) were examined between 2008 and 2010 . No bird was reactive at hemagglutination-inhibition (HI) for antibodies against Mycoplasma gallisepticum (Mg). Two Caracara plancus (2/68) had HI titers (16-32) against Newcastle disease virus. No Chlamydophila psittaci DNA was detected in the liver (PCR; n=95). Blood smears (Giemsa; n=89) and spleen fragments (PCR; n=82) were 13.5% and 8.5% positive, respectively, for Haemoproteus only. Necropsy of Cathartiformes (n=10), Falconiformes (n=42) and Strigiformes (n=57) showed that trauma injuries were the main cause (63.3%) of admission and death, being fractures (38.5%) of the thoracic limbs (57.1%) the most frequent. Nematode (12.8%), cestode (1.8%), trematode (0.9%), and acanthocephalan (2.7%) parasite infections were relevant. Mites (Acari) were the most frequent (17.4%) external parasites, particularly Ornithonyssus sylviarum in Asio clamator and Amblyomma cajennense in Tyto alba. Chewing lice (10.1%) and Pseudolynchia spp. (9.2%) were also found. Histomonas spp. (6.4%) was found in the ceca of Bubo virginianus, Athene cunicularia, Tyto alba, and Asio clamator, but not in Falconiformes or Cathartiformes. Trichomonas spp. (oral cavity, pharynx and upper esophagus; 9.1%) was detected in Falconiformes and Strigiformes, but not in Cathartiformes. Trichomonas spp. were found in A. cunicularia, Asio clamator, Glaucidium brasilianum and Tyto alba (Strigiformes), and in Rupornis magnirostris, Milvago chimachima, Falco femoralis, Falco sparverius and Caracara plancus (Falconiformes). Coccidia (9.1%) (Sarcocystis spp., 6.4%) and mycosis were observed in most Tyto alba (70%). The evaluated Orders may not pose risks for commercial poultry production. Habitat loss and urban adaptation may be increasingly affecting raptors.(AU)