Background: Bacterial Chondronecrosis with Osteomyelitis (BCO) is a significant issue affecting the welfare and economy of the broiler industry, causing substantial revenue losses annually. This disease is frequently associated with Staphylococcus spp. and Enterococcus spp. infections and necrosis of leg and vertebral bones. The typical annual lameness incidence of approximately 3–5% may increase to 30% during outbreaks. Neither the etiology or pathogenesis of the disease has been comprehended, nor have effective preventative measures been identified. Electron beam (eBeam) technology is renowned for producing efficient whole-cell vaccines by preventing bacterial multiplication through irreversible DNA shredding while preserving the integrity of membrane proteins (immunogenic epitopes). This study aims to reduce BCO-induced lameness in broiler chickens via in ovo immunization using eBeam-inactivated multi-strain Staphylococcus. Methods: A total 1080 birds were assigned to four vaccination groups: eBeam-inactivated, formalin-inactivated, combination of eBeam- and formalin-inactivated, and sham (vehicle). The birds were directly exposed to aerosolized, natural BCO challenge until 56 days of age. Results: Birds vaccinated with the eBeam-inactivated Staphylococcus vaccine showed a significant reduction (>50%) in daily cumulative lameness compared to other groups and a decrease in Staphylococcus colonization was observed in the leg joints of treated birds. Conclusions: the eBeam-inactivated Staphylococcus vaccine successfully prevented BCO lameness in broiler chickens.

Bacterial Chondronecrosis with Osteomyelitis (BCO) is a significant issue affecting the animal welfare and economy of the commercial broiler industry, resulting in revenue losses of hundreds of millions of dollars annually. This metabolic disease is frequently associated with Staphylococcus spp. and Enterococcus spp. infections and necrosis of leg and vertebral bones. The typical annual lameness incidence of approximately 3-5% may increase to 30% during outbreaks. Neither the complete etiology and pathogenesis of the disease has been fully understood, nor have effective, commercially available measures of total prevention been identified. Electron beam (eBeam) technology is renowned for producing efficient whole-cell vaccines by preventing bacterial multiplication through irreversible DNA shredding while preserving the integrity of membrane proteins (immunogenic epitopes). This study aims to reduce BCO-induced lameness in broiler chickens via in ovo immunization using an eBeam-inactivated multi-strain Staphylococcus vaccine. 1080 birds were assigned to four vaccination groups: eBeam-inactivated, formalin-inactivated, combination of eBeam and formalin-inactivated, and sham (vehicle). Birds were directly exposed to aerosolized, natural BCO challenge until 56 days of age. Birds vaccinated with the eBeam-inactivated Staphylococcus vaccine showed significant reduction (>50%) in daily cumulative lameness compared to other groups and a decrease of Staphylococcus colonization in the leg-joints of treated birds.

Kappa Casein Gene Polymorphism in Local Tunisian Goats