Characterization of coccidiosis and evaluation of suggestive cases of subclinical necrotic enteritis in broilers / Caracterização de coccidiose e avaliação de casos sugestivos de enterite necrótica subclínica em frangos de corte

This study performed the characterization of coccidiosis in broilers and evaluated the occurrence of suggestive cases of necrotic enteritis (NE), seeking if there is an association between the diseases in Brazilian flocks. Two hundred and fifty-six birds from 32 flocks were evaluated. Macroscopic and histopathological lesions were graduated for coccidiosis and NE. Intestinal content was investigated by polymerase chain reaction (PCR) for seven species of Eimeria and by selective anaerobic culture for Clostridium perfringens and identification of the NetB gene. Flocks positive for coccidiosis represented 93.8%. Macroscopic lesions of coccidiosis were Grade 1 for E. acervulina (27%); E. tenella (9.7%) and E. maxima (8.9%). Histopathological evaluation showed Grade 1 in duodenum (38.2%); jejunum (21.4%); cecum (9.3%) and ileum (5%). PCR demonstrated positivity for E. tenella (21.9%), E. maxima (18.8%), and E. acervulina (3.1%). Suggestive macroscopic lesions of necrotic enteritis ranged from Grade 1 (16%), 2 (23%) and 3 (10,9%). Histopathology indicated the absence of necrosis, showing only hemorrhage in the mucosa and submucosa, with the presence of Eimeria spp. Clostridium perfringens type A netB+ was not isolated, demonstrating that macroscopic lesions found mostly in the jejunum did not characterize NE, based on histopathology and negativity of the NetB gene. The study suggests that, due to the high occurrence of coccidiosis, many macroscopic findings suggestive of NE are, in fact, attributed to atypical lesions caused by the reproduction of Eimeria spp.

Este estudo realizou a caracterização de coccidiose em frangos de corte e avaliou a ocorrência de casos sugestivos de enterite necrótica (EN), buscando se há alguma associação entre estas duas enfermidades em lotes de frango de corte no Brasil. Foram avaliadas 256 aves de 32 lotes. Lesões macroscópicas e histopatológicas foram graduadas para coccidiose e EN. O conteúdo intestinal foi investigado por reação em cadeia da polimerase (PCR) para sete espécies de Eimeria e por cultura anaeróbia seletiva para Clostridium perfringens e identificação do gene NetB. Os lotes positivos para coccidiose representaram 93,8%. Lesões macroscópicas de coccidiose foram de Grau 1 para E. acervulina (27%); E. tenella (9,7%) e E. maxima (8,9%). A avaliação histopatológica mostrou Grau 1 no duodeno (38,2%); jejuno (21,4%); ceco (9,3%) e íleo (5%). A PCR demonstrou positividade para E. tenella (21,9%), E. maxima (18,8%) e E. acervulina (3,1%). Lesões macroscópicas sugestivas de enterite necrótica variaram de grau 1 (16%), 2 (23%) e 3 (10,9%). A histopatologia indicou ausência de necrose, apresentando apenas hemorragia em mucosa e submucosa, com presença de Eimeria spp. Clostridium perfringens tipo A netB + não foi isolado, demonstrando que lesões macroscópicas encontradas principalmente no jejuno não caracterizaram NE, com base na histopatologia e negatividade do gene NetB. O estudo sugere que, em virtude da alta ocorrência de coccidiose nos lotes, muitos achados macroscópicos sugestivos de EN são, na verdade, atribuídos a lesões atípicas provocadas pela reprodução de Eimeria spp.

Comparison of macroscopy, histopathology and PCR for diagnosing Eimeria spp. in broiler chickens / Comparação da macroscopia, histopatologia e PCR para o diagnóstico de Eimeria spp. em frangos de corte

Coccidiosis is a disease of great importance in industrial poultry. The correct diagnosis directs the poultry industry to its best treatment and control. Thus, a survey of Eimeria spp. was carried out in intestines of 64 broiler flocks, with an average age of 29 days. Eight broilers from each flock were randomly removed from the slaughter line, in a total of 512 samples. Macroscopic and histopathological lesions in the intestine were classified into Scores 0 to 4. Polymerase chain reaction (PCR) was used to research the oocysts from the seven species of Eimeria spp. in the intestinal content. The macroscopic evaluations showed that 59.4% (38/64) of the flocks were positive for E. acervulina, 32.8% (21/64) for E. maxima, 29.7% (19/64) for E. tenella, and 34.4% (22/64) for E. brunetti. The histopathological evaluation showed that 87.5% (56/64) of the flocks had at least one broiler with parasitic structures compatible with Eimeria spp. in the duodenum, 70.3% (45/64) in the jejunum, 18.8% (12/64) in the ileum, 46.9% (30/64) in the cecum, and 4.7% (3/64) in the colon. In PCR, 21.9% (14/64) of the flocks were positive for E. acervulina, 12.5% (8/64) for E. maxima, 3.1% (2/64) for E. mitis, and 32.8% (21/64) for E. tenella. The Kappa Cohen test between macroscopy, histopathology, and PCR demonstrated concordance ranging from weak to moderate with the exception of histopathology and PCR of the cecum, which was strong. In the comparison between macroscopy and histopathology, there were significative differences between Scores 0 and 1 (apart from the cecum). For Score 3, there were significative differences in duodenum, jejunum and cecum (p<0.05). In conclusion, the macroscopic diagnosis and PCR can generate false-negative results, and the histopathological exam proved to be effective, making it essential to associate different techniques for the correct diagnosis of Eimeria spp. in broiler chickens.

A coccidiose é uma doença de grande importância na avicultura industrial. O diagnóstico correto direciona a indústria avícola ao seu melhor tratamento e controle. Desta forma, realizou-se a pesquisa de Eimeria spp. em intestinos de 64 lotes de frangos de corte, com idade média de 29 dias. Em cada lote foram retirados aleatoriamente oito frangos da linha de abate, totalizando 512. Os intestinos foram classificados na macroscopia e na histopatologia em Grau de 0 a 4. No conteúdo intestinal pesquisou-se por reação em cadeia da polimerase (PCR) oocistos das sete espécies de Eimeria. As avaliações macroscópicas demonstraram que 59,4% (38/64) dos lotes foram positivos para E. acervulina, 32,8% (21/64) para E. maxima, 29,7% (19/64) para E. tenella e 34,4% (22/64) para E. brunetti. Na avaliação histopatológica, 87,5% (56/64) dos lotes apresentaram pelo menos um frango com estruturas parasitárias compatíveis com Eimeria spp. no duodeno, 70,3% (45/64) no jejuno, 18,8% (12/64) no íleo, 46,9% (30/64) no ceco e 4,7% (3/64) no cólon. Na PCR 21,9% (14/64) dos lotes foram positivos para E. acervulina, 12,5% (8/64) para E. maxima, 3,1% (2/64) para E. mitis e 32,8% (21/64) para E. tenella. O teste de concordância de Kappa Cohen entre macroscopia, histopatologia e PCR demonstrou concordância variando de fraca a moderada com exceção da histopatologia e PCR do ceco que foi forte. Na comparação dos graus de macroscopia e histopatologia, foram encontradas diferenças significativas entre o Grau 0 e 1 (exceto no ceco) e no Grau 3 houve diferença para duodeno, jejuno e cecos (p<0,05). Conclui-se que o diagnóstico macroscópico e a PCR podem gerar resultados falsos negativos e que o exame histopatológico se demostrou eficaz, tornando fundamental a associação de diferentes técnicas para o correto diagnóstico de Eimeria spp. em frangos de corte.

Comparison of macroscopy, histopathology and PCR for diagnosing Eimeria spp. in broiler chickens

ABSTRACT: Coccidiosis is a disease of great importance in industrial poultry. The correct diagnosis directs the poultry industry to its best treatment and control. Thus, a survey of Eimeria spp. was carried out in intestines of 64 broiler flocks, with an average age of 29 days. Eight broilers from each flock were randomly removed from the slaughter line, in a total of 512 samples. Macroscopic and histopathological lesions in the intestine were classified into Scores 0 to 4. Polymerase chain reaction (PCR) was used to research the oocysts from the seven species of Eimeria spp. in the intestinal content. The macroscopic evaluations showed that 59.4% (38/64) of the flocks were positive for E. acervulina, 32.8% (21/64) for E. maxima, 29.7% (19/64) for E. tenella, and 34.4% (22/64) for E. brunetti. The histopathological evaluation showed that 87.5% (56/64) of the flocks had at least one broiler with parasitic structures compatible with Eimeria spp. in the duodenum, 70.3% (45/64) in the jejunum, 18.8% (12/64) in the ileum, 46.9% (30/64) in the cecum, and 4.7% (3/64) in the colon. In PCR, 21.9% (14/64) of the flocks were positive for E. acervulina, 12.5% (8/64) for E. maxima, 3.1% (2/64) for E. mitis, and 32.8% (21/64) for E. tenella. The Kappa Cohen test between macroscopy, histopathology, and PCR demonstrated concordance ranging from weak to moderate with the exception of histopathology and PCR of the cecum, which was strong. In the comparison between macroscopy and histopathology, there were significative differences between Scores 0 and 1 (apart from the cecum). For Score 3, there were significative differences in duodenum, jejunum and cecum (p 0.05). In conclusion, the macroscopic diagnosis and PCR can generate false-negative results, and the histopathological exam proved to be effective, making it essential to associate different techniques for the correct diagnosis of Eimeria spp. in broiler chickens.

RESUMO: A coccidiose é uma doença de grande importância na avicultura industrial. O diagnóstico correto direciona a indústria avícola ao seu melhor tratamento e controle. Desta forma, realizou-se a pesquisa de Eimeria spp. em intestinos de 64 lotes de frangos de corte, com idade média de 29 dias. Em cada lote foram retirados aleatoriamente oito frangos da linha de abate, totalizando 512. Os intestinos foram classificados na macroscopia e na histopatologia em Grau de 0 a 4. No conteúdo intestinal pesquisou-se por reação em cadeia da polimerase (PCR) oocistos das sete espécies de Eimeria. As avaliações macroscópicas demonstraram que 59,4% (38/64) dos lotes foram positivos para E. acervulina, 32,8% (21/64) para E. maxima, 29,7% (19/64) para E. tenella e 34,4% (22/64) para E. brunetti. Na avaliação histopatológica, 87,5% (56/64) dos lotes apresentaram pelo menos um frango com estruturas parasitárias compatíveis com Eimeria spp. no duodeno, 70,3% (45/64) no jejuno, 18,8% (12/64) no íleo, 46,9% (30/64) no ceco e 4,7% (3/64) no cólon. Na PCR 21,9% (14/64) dos lotes foram positivos para E. acervulina, 12,5% (8/64) para E. maxima, 3,1% (2/64) para E. mitis e 32,8% (21/64) para E. tenella. O teste de concordância de Kappa Cohen entre macroscopia, histopatologia e PCR demonstrou concordância variando de fraca a moderada com exceção da histopatologia e PCR do ceco que foi forte. Na comparação dos graus de macroscopia e histopatologia, foram encontradas diferenças significativas entre o Grau 0 e 1 (exceto no ceco) e no Grau 3 houve diferença para duodeno, jejuno e cecos (p 0,05). Conclui-se que o diagnóstico macroscópico e a PCR podem gerar resultados falsos negativos e que o exame histopatológico se demostrou eficaz, tornando fundamental a associação de diferentes técnicas para o correto diagnóstico de Eimeria spp. em frangos de corte.

Comparison of macroscopy, histopathology and PCR for diagnosing Eimeria spp. in broiler chickens / Comparação da macroscopia, histopatologia e PCR para o diagnóstico de Eimeria spp. em frangos de corte

Coccidiosis is a disease of great importance in industrial poultry. The correct diagnosis directs the poultry industry to its best treatment and control. Thus, a survey of Eimeria spp. was carried out in intestines of 64 broiler flocks, with an average age of 29 days. Eight broilers from each flock were randomly removed from the slaughter line, in a total of 512 samples. Macroscopic and histopathological lesions in the intestine were classified into Scores 0 to 4. Polymerase chain reaction (PCR) was used to research the oocysts from the seven species of Eimeria spp. in the intestinal content. The macroscopic evaluations showed that 59.4% (38/64) of the flocks were positive for E. acervulina, 32.8% (21/64) for E. maxima, 29.7% (19/64) for E. tenella, and 34.4% (22/64) for E. brunetti. The histopathological evaluation showed that 87.5% (56/64) of the flocks had at least one broiler with parasitic structures compatible with Eimeria spp. in the duodenum, 70.3% (45/64) in the jejunum, 18.8% (12/64) in the ileum, 46.9% (30/64) in the cecum, and 4.7% (3/64) in the colon. In PCR, 21.9% (14/64) of the flocks were positive for E. acervulina, 12.5% (8/64) for E. maxima, 3.1% (2/64) for E. mitis, and 32.8% (21/64) for E. tenella. The Kappa Cohen test between macroscopy, histopathology, and PCR demonstrated concordance ranging from weak to moderate with the exception of histopathology and PCR of the cecum, which was strong. In the comparison between macroscopy and histopathology, there were significative differences between Scores 0 and 1 (apart from the cecum). For Score 3, there were significative differences in duodenum, jejunum and cecum (p<0.05). In conclusion, the macroscopic diagnosis and PCR can generate false-negative results, and the histopathological exam proved to be effective, making it essential to associate different techniques for the correct diagnosis of Eimeria spp. in broiler chickens.(AU)

A coccidiose é uma doença de grande importância na avicultura industrial. O diagnóstico correto direciona a indústria avícola ao seu melhor tratamento e controle. Desta forma, realizou-se a pesquisa de Eimeria spp. em intestinos de 64 lotes de frangos de corte, com idade média de 29 dias. Em cada lote foram retirados aleatoriamente oito frangos da linha de abate, totalizando 512. Os intestinos foram classificados na macroscopia e na histopatologia em Grau de 0 a 4. No conteúdo intestinal pesquisou-se por reação em cadeia da polimerase (PCR) oocistos das sete espécies de Eimeria. As avaliações macroscópicas demonstraram que 59,4% (38/64) dos lotes foram positivos para E. acervulina, 32,8% (21/64) para E. maxima, 29,7% (19/64) para E. tenella e 34,4% (22/64) para E. brunetti. Na avaliação histopatológica, 87,5% (56/64) dos lotes apresentaram pelo menos um frango com estruturas parasitárias compatíveis com Eimeria spp. no duodeno, 70,3% (45/64) no jejuno, 18,8% (12/64) no íleo, 46,9% (30/64) no ceco e 4,7% (3/64) no cólon. Na PCR 21,9% (14/64) dos lotes foram positivos para E. acervulina, 12,5% (8/64) para E. maxima, 3,1% (2/64) para E. mitis e 32,8% (21/64) para E. tenella. O teste de concordância de Kappa Cohen entre macroscopia, histopatologia e PCR demonstrou concordância variando de fraca a moderada com exceção da histopatologia e PCR do ceco que foi forte. Na comparação dos graus de macroscopia e histopatologia, foram encontradas diferenças significativas entre o Grau 0 e 1 (exceto no ceco) e no Grau 3 houve diferença para duodeno, jejuno e cecos (p<0,05). Conclui-se que o diagnóstico macroscópico e a PCR podem gerar resultados falsos negativos e que o exame histopatológico se demostrou eficaz, tornando fundamental a associação de diferentes técnicas para o correto diagnóstico de Eimeria spp. em frangos de corte.(AU)

Avaliação anatomopatológica de testículos de bovinos(Bos taurus) superprecoces submetidos a imunocastração / Anatomopathological evaluation of young bulls (Bos taurus) testicles submitted to immunocastration

Background: Immunocastration is a less invasive and painless procedure compared to surgical castration, which causesgreater stress to animals, especially when performed improperly. Immunocastration stimulates the production of antibodiesagainst Gonadotropin-Releasing Hormone (GnRH), temporarily blocking the hormone production by the male gonads.Anatomopathological evaluation of animals submitted to immunocastration with the establishment of different degrees oftesticular degeneration helps to evaluate the efficacy of the different dose ranges used for this procedure. Because of thescarcity of information about this procedure in young bulls, the study aimed to compare the immunocastrated and noncastrated animals.Materials, Methods & Results: Eighteen Angus-Limousin bulls were used from weaning (7±1 months) to slaughtering(15±1 months) with the establishment of two groups composed of nine non-castrated (NC) and nine immunocastrated (IC)animals. In the IC group, three doses of GnRH synthesis inhibitor vaccine (Bopriva®) were applied on days 0 (weaning),87 and 223. At slaughter, scrotal circumference, weight (kg), width (cm), length (cm) and total size (width x length) of thetesticles were obtained, then were routinely processed for histopathological analysis. Four degrees of testicular degeneration was established: grade 0 (no changes), grade 1 (mild), grade 2 (moderate) and grade 3 (severe). Statistical analysiswas performed using Student’s t-test to compare the means of macroscopic variables. The scrotal circumference startedto decrease in the IC animals on day 132, with a certain growth from day 194. There was a significant difference betweenthe two groups for width (P = 0.001), length (P = 0.004), total size (P = 0.003) and scrotal circumference (P = 0.04).Testicles of the IC group tended to be lighter (P = 0.06)...

Surto de Pasteurelose por Pasteurella multocida tipo A em coelhos (Oryctolagus cuniculus) / Pasteurellosis outbreak due to Pasteurella multocida type A in rabbits (Oryctolagus cuniculus)

Background: Pasteurellosis is a common disease of cattle, pigs, and poultry, which rarely affects humans. In rabbits, therespiratory presentation of the disease is frequently reported. Clinical signs related to bronchopneumonia include sneezing, lung stertors, oculonasal discharge, dyspnea and cyanosis. Infection may lead to otitis, conjunctivitis, abscesses andsepsis. Furthermore, Pasteurella multocida infection may lead to sudden death without clinical manifestations. Reports ofpasteurellosis in rabbits are scarce in Brazil. Therefore, the objective of this article is to describe an outbreak of pasteurellosis with high mortality in a rabbity in the State of Santa Catarina, Brazil.Cases: Two adult rabbits were submitted for necropsy at the Veterinary Pathology Laboratory of the Instituto Federal Catarinense- Campus Concórdia, within an interval of twenty days. Herd was represented by 40 animals, of which six fattening rabbits andthree breeders died. Animals were kept in suspended cages with slatted floor. Clinical signs were represented by prostration,sneezing, and mucopurulent nasal discharge. In addition, wounds were observed in the distal portion of the limbs. Death occurredup to two days after the onset of clinical signs. Necropsies were performed and tissue samples were collected for histopathologic,immunohistochemical and microbiologic (bacterial culture and antibiogram) exams. At the necropsy, severe diffuse fibrinousexudate covering the pericardium sac, visceral and parietal pleural surfaces was noted, as well as multiple diaphragm adhesions.In addition, the lungs presented diffuse red coloration and showed multiple abscesses ranging from 0.3 to 1cm in diameter. Thenasal sinus and the tracheal mucosa showed diffuse reddening (rabbits 1 and 2). Abscesses up to 2 cm in diameter were observedin the mammary glands (rabbit 1), heart and kidneys (rabbit 2). The urinary bladder...

Surto de Pasteurelose por Pasteurella multocida tipo A em coelhos (Oryctolagus cuniculus) / Pasteurellosis outbreak due to Pasteurella multocida type A in rabbits (Oryctolagus cuniculus)

Background: Pasteurellosis is a common disease of cattle, pigs, and poultry, which rarely affects humans. In rabbits, therespiratory presentation of the disease is frequently reported. Clinical signs related to bronchopneumonia include sneezing, lung stertors, oculonasal discharge, dyspnea and cyanosis. Infection may lead to otitis, conjunctivitis, abscesses andsepsis. Furthermore, Pasteurella multocida infection may lead to sudden death without clinical manifestations. Reports ofpasteurellosis in rabbits are scarce in Brazil. Therefore, the objective of this article is to describe an outbreak of pasteurellosis with high mortality in a rabbity in the State of Santa Catarina, Brazil.Cases: Two adult rabbits were submitted for necropsy at the Veterinary Pathology Laboratory of the Instituto Federal Catarinense- Campus Concórdia, within an interval of twenty days. Herd was represented by 40 animals, of which six fattening rabbits andthree breeders died. Animals were kept in suspended cages with slatted floor. Clinical signs were represented by prostration,sneezing, and mucopurulent nasal discharge. In addition, wounds were observed in the distal portion of the limbs. Death occurredup to two days after the onset of clinical signs. Necropsies were performed and tissue samples were collected for histopathologic,immunohistochemical and microbiologic (bacterial culture and antibiogram) exams. At the necropsy, severe diffuse fibrinousexudate covering the pericardium sac, visceral and parietal pleural surfaces was noted, as well as multiple diaphragm adhesions.In addition, the lungs presented diffuse red coloration and showed multiple abscesses ranging from 0.3 to 1cm in diameter. Thenasal sinus and the tracheal mucosa showed diffuse reddening (rabbits 1 and 2). Abscesses up to 2 cm in diameter were observedin the mammary glands (rabbit 1), heart and kidneys (rabbit 2). The urinary bladder...(AU)

Avaliação anatomopatológica de testículos de bovinos(Bos taurus) superprecoces submetidos a imunocastração / Anatomopathological evaluation of young bulls (Bos taurus) testicles submitted to immunocastration

Background: Immunocastration is a less invasive and painless procedure compared to surgical castration, which causesgreater stress to animals, especially when performed improperly. Immunocastration stimulates the production of antibodiesagainst Gonadotropin-Releasing Hormone (GnRH), temporarily blocking the hormone production by the male gonads.Anatomopathological evaluation of animals submitted to immunocastration with the establishment of different degrees oftesticular degeneration helps to evaluate the efficacy of the different dose ranges used for this procedure. Because of thescarcity of information about this procedure in young bulls, the study aimed to compare the immunocastrated and noncastrated animals.Materials, Methods & Results: Eighteen Angus-Limousin bulls were used from weaning (7±1 months) to slaughtering(15±1 months) with the establishment of two groups composed of nine non-castrated (NC) and nine immunocastrated (IC)animals. In the IC group, three doses of GnRH synthesis inhibitor vaccine (Bopriva®) were applied on days 0 (weaning),87 and 223. At slaughter, scrotal circumference, weight (kg), width (cm), length (cm) and total size (width x length) of thetesticles were obtained, then were routinely processed for histopathological analysis. Four degrees of testicular degeneration was established: grade 0 (no changes), grade 1 (mild), grade 2 (moderate) and grade 3 (severe). Statistical analysiswas performed using Students t-test to compare the means of macroscopic variables. The scrotal circumference startedto decrease in the IC animals on day 132, with a certain growth from day 194. There was a significant difference betweenthe two groups for width (P = 0.001), length (P = 0.004), total size (P = 0.003) and scrotal circumference (P = 0.04).Testicles of the IC group tended to be lighter (P = 0.06)...(AU)