Vertebral Osteomyelitis in Broilers: A Review

ABSTRACT 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.

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.

PERMEABILIDADE INTESTINAL, TRANSLOCAÇÃO BACTERIANA E OCORRÊNCIA DE OSTEOMIELITE VERTEBRAL EM FRANGOS SUBMETIDOS AO ESTRESSE ENTÉRICO

A osteomielite vertebral é uma doença emergente na avicultura mundial, caracterizada por imobilidade e mortalidade de frangos e matrizes de corte devido ao processo infeccioso na quarta vértebra torácica (T4). Assim, objetivou-se desenvolver um modelo experimental induzidopelo estresse entéricopara o melhor entendimento da patogênese de osteomielite vertebral, além de investigar o papel do estresse entérico na permeabilidade intestinal e translocação bacteriana para fígado, baço e coluna vertebral de frangos de corte. As cepas de Enterococcus cecorum(11 TXs e 11 TXb) que apresentavam os fatores de virulência: polissacarídeo capsular I e II, antígeno de polissacarídeo enterocócico M e P, proteína lipoato sintase e proteína de superfície LPTXG3 foram inoculadas após estresse entérico induzido pela utilização de dexametasona por sete dias na ração (DEX), grãos secos de destilaria com solúveis- DDGS (30%) na dieta e a restrição alimentar (RA) de 24 horas. Os achados macroscópicos de lesões responsáveis pela claudicação afetaram 19,37% (186/960) das aves submetidas ao estresse entérico e 9,06% (87/960) apresentaram osteomielite vertebral. O grupo que apresentou inflamação entérica induzida porDDGS na dieta apresentou aumento (p<0,05)na ocorrência de osteomielite vertebral e claudicação.A permeabilidade intestinal, avaliada pelos níveis séricos de FITC-d, aumentou(p<0,05) significativamentenos tratamentosDEX aos 16, 23 e 30 dias de idade e RA aos 30 dias de idade. Após inoculação de E. cecorum, houve aumento (p<0,05) da contagem de bactérias microaerófilas no fígado e baço no grupo DEX aos 20 dias. Da mesma forma, foi verificado um aumento dessas bactérias na T4 no grupo RA aos 27 dias de idade e no grupo DEX aos 34 dias.Por meio de isolamento bacteriano, identificou-se uma diversidade de bactérias como espécies de Enterococcus, Streptococcus, Staphylococcus, Lactobacillus, bem como Escherichia colina T4, sugerindo que outros agentes microbianos, além de E. cecorum, podem estar envolvidos nas lesões de osteomielite vertebral.Portanto, o modelo de reprodução experimental de osteomielite vertebral induzido pelo estresse entérico em frangos de corte possibilita o estudo de lesões da osteomielite vertebral, o que favorece sua utilização na pesquisa aplicada de estratégias preventivas e terapêuticas para essa doença. Além disso, conclui-se que o estresse entérico aumenta a permeabilidade intestinal e propicia a translocação de bactérias oportunistas para o fígado, baço e coluna vertebral de frangos de corte podendo levar o desenvolvimento de osteomielite vertebral em frangos de corte.

Vertebral osteomyelitis is an emerging disease in the world poultry industry, characterized by immobility and mortality of broilers andbreeders chicken due to the infectious process in the fourth thoracic vertebra (T4). The aim of this study was to develop an experimental model induced by enteric stress to better understand the pathogenesis of vertebral osteomyelitis, as well as to investigate the role of enteric stress in intestinal permeability and bacterial translocation to liver, spleen and vertebral column of broiler chickens. Enterococcus cecorum strains (11 TXs and 11 TXb) that presented the virulence genes virulence factors: capsular polysaccharide I and II, enterococcal polysaccharide antigen M and P, protein lipoate synthase and surface protein LPTXG3 were inoculated after enteric stress induced by the use of dexamethasone for seven days in the diet (DEX), dried distilled grain with solubles - DDGS (30%) in the diet and the 24-hour food restriction (RA). The macroscopic findings of lesions responsible for claudication affected 19.37% (186/960) of the birds submitted to enteric stress and 9.06% (87/960) had vertebral osteomyelitis.The group that presented enteric inflammation induced by DDGS in the diet had an increase (p<0.05) in the incidence of vertebral osteomyelitis and lameness. The intestinal permeability, as assessed by serum FITC-d levels, increased (p<0.05) inDEX at 16, 23 e 30 days of age and RA at30 days of age. After inoculation of E. cecorum, there was an increase (p<0.05) in microaerophilic bacteria in the liver and spleen in the DEX group at 20 days.Likewise, an increase of these bacteria was observed in T4 in the RA group at 27 days of age and in the DEX group at 34 days.Bacterial isolation identified a diversity of bacteria as species of Enterococcus, Streptococcus, Staphylococcus, Lactobacillus, as well as Escherichia coli in T4,suggesting that other microbial agents besides E. cecorum may be involved in vertebral osteomyelitis lesions. Therefore, the experimental reproduction model of vertebral osteomyelitis induced by enteric stress in broilers makes it possible to study vertebral osteomyelitis lesions, which favors its use in the applied research of preventive and therapeutic strategies for this disease. In addition, it is concluded that enteric stress increases intestinal permeability and promotes the translocation of opportunistic bacteria to the liver, spleen and spine of broiler chickens, which may lead to the development of vertebral osteomyelitis in broilers.