A Novel Presentation of Clostridium perfringens in Young Broilers.

Necrotic enteritis (NE) is an important intestinal disease of commercial poultry associated with poor performance, high mortality, and significant economic loss. In this case report, a novel presentation of NE is described in young broilers. Initially, affected farms presented with a moderate increase in mortality at or before 19 days of age. Farms experiencing the disease syndrome belonged to two complexes of the same company. However, all farms sourced chicks from the same hatchery. Farm postmortem examinations revealed moderate to severe enteritis of the upper small intestine characterized by multifocal, irregular, plaque-like, mucosal ulcerations. Additionally, thinning of the intestinal wall with consequential distension and ballooning and a necrotic, pseudomembranous layer covering the mucosa were observed in some birds. Clinically affected birds were submitted to the Poultry Research and Diagnostic Laboratory at Mississippi State University for further evaluation. Birds were between 5 and 11 days of age and presented with similar gross lesions. Anaerobic culture was performed, and Clostridium perfringens was isolated from affected intestinal sections. Environmental sampling at the hatchery was also performed to evaluate the presence and load of clostridial organisms. Clostridium perfringens was isolated from samples collected in the egg room, hatchers/hatch halls, separator room, processing room, and transport trucks. Furthermore, VITEK® mass spectrometry matrix-assisted laser desorption ionization time-of-flight results indicated a 99.9% genetic relatedness between hatchery and live bird isolates, demonstrating an epidemiologic link between clinically affected birds and the hatchery as a point source. This novel presentation of C. perfringens in young broilers warrants attention because proper development of the gastrointestinal tract in the first weeks of life is critical for competitive production in the modern broiler.

Reporte de caso- Nueva presentación de Clostridium perfringens en pollos de engorde jóvenes. La enteritis necrótica es una enfermedad intestinal importante de las aves comerciales asociada con un bajo rendimiento, alta mortalidad y pérdidas económicas significativas. En este reporte de caso, se describe una presentación nueva de enteritis necrótica en pollos de engorde jóvenes. Inicialmente, las granjas afectadas presentaron un aumento moderado en la mortalidad a los 19 días de edad o antes. Las granjas que presentaban el síndrome de la enfermedad pertenecían a dos complejos de la misma empresa. Sin embargo, todas las granjas obtuvieron pollitos de la misma incubadora. Los exámenes post mortem de la granja revelaron una enteritis de moderada a severa en la parte superior del intestino delgado caracterizada por ulceraciones de la mucosa multifocales, irregulares y similares a placas. Además, en algunas aves se observó adelgazamiento de la pared intestinal con la consiguiente distensión e hinchazón y una capa pseudomembranosa necrótica que cubría la mucosa. Las aves clínicamente afectadas se enviaron al Laboratorio de Investigación y Diagnóstico Avícola de la Universidad Estatal de Mississippi para una evaluación adicional. Las aves tenían entre cinco y once días de edad y presentaban lesiones macroscópicas similares. Se realizó cultivo de anaerobios y se aisló Clostridium perfringens de las secciones intestinales afectadas. También se realizaron muestreos ambientales en la incubadora para evaluar la presencia y carga de organismos clostridiales. Se aisló Clostridium perfringens de muestras recolectadas en la sala de huevos, incubadoras/salones de incubación, sala de separación, sala de procesamiento y camiones de transporte. Además, los resultados de la espectrometría de masas MALDI-TOF de VITEK® indicaron una relación genética del 99.9 % entre los aislados de la incubadora y de aves vivas, lo que demuestra un vínculo epidemiológico entre las aves clínicamente afectadas y la incubadora como fuente de infección común. Esta nueva presentación de C. perfringens en pollos de engorde jóvenes merece atención porque el desarrollo adecuado del tracto gastrointestinal en las primeras semanas de vida es fundamental para la producción competitiva en el pollo de engorde moderno.

Protection following simultaneous vaccination with three or four different attenuated live vaccine types against infectious bronchitis virus.

Two or more different live attenuated infectious bronchitis virus (IBV) vaccine types are often given to broilers to induce homologous protection as well as to broaden protection against other IBV types in the field. However, the ability of broilers to respond to three or four different antigenic types of IBV vaccine has not been examined experimentally. In this study, we vaccinated one-day-old broiler chicks by eyedrop with three or four different IBV vaccine types simultaneously. The presence and relative amount of each vaccine was examined in all of the birds by IBV type-specific real-time RT-PCR at 5 days post-vaccination and each vaccine was detected in all of the birds given that vaccine. The birds were challenged at 28 days of age and protection was measured by clinical signs, virus detection and by ciliostasis. Birds vaccinated with three different IBV types (Ark, Mass and GA98) were protected against challenge with each of those IBV types and were partially protected against challenge with the GA08 virus. Birds vaccinated with four different IBV types (Ark, Mass, GA98 and GA08) were protected against challenge with each of those IBV types with the exception of Mass challenged birds which clearly had 3/11 birds not protected based on individual ciliostasis scores, but had an average ciliostasis score of >50% which is considered protected. The results are important for the control of IBV because they indicate that simultaneous vaccination with up to four different IBV vaccine types can provide adequate protection against challenge for each type.