Our prior research demonstrated a 20% to 25% reduction in bacterial chondronecrosis with osteomyelitis (BCO) lameness in broilers with organic Zn, Mn, and Cu (Availa^® ZMC) supplementation. Expanding on this, we investigated the optimal timing for Availa^® ZMC feeding to mitigate BCO lameness and reduce feed additive costs in the poultry industry. In this study, we compared the application of 0.15% Availa^® ZMC for 56 days, the first 28 days, and the last 28 days. The experimental design was a randomized block design involving 1560 one-day-old chicks distributed across two wire-floor pens as BCO source infection and four treatment groups with six replicates. The source of BCO infection exhibited a cumulative lameness incidence of 83%, whereas the negative control group showed a 77% cumulative incidence of lameness (p = 0.125). Administering 0.15% of Availa^® ZMC during the initial 28 d resulted in a 41.3% reduction in BCO incidence, significantly different from the supplementation during the last 28 d (p < 0.05). However, this reduction did not differ substantially (p > 0.05) from the 56d application period. Hence, administering 0.15% Availa^® ZMC during the first four weeks emerges as the optimal timing protocol, providing a defense against lameness comparable to the continuous supplementation throughout the complete production duration. Implementing this feeding approach reduces the cost of feed additive, promotes the health of skeletal bones, and effectively protects against BCO lameness in broilers, offering a valuable consideration for producers seeking optimal outcomes in the poultry industry.

This review provides an overview of electron beam (eBeam) technology and its applications across a wide variety of disciplines. More importantly, it discusses this technology’s advantages and its benefits in developing inactivated vaccines. eBeam technology is currently being used all around the world for a variety of industrial applications, extending from food pasteurization to the cross-linking of polymers in the wire and cable industries. It is a successful emerging alternative for developing vaccines against bacterial, protozoan, and viral pathogens. This review includes a descriptive account of the mechanism of action of eBeam and how this technology achieves the complete inactivation of pathogens while retaining the integrity of their surface epitopes. This unique advantage is crucial for the production of efficacious vaccines. This review provides a detailed account of the usage of eBeam technology for developing vaccines to protect a multitude of hosts against a wide range of pathogens. eBeam-inactivated vaccines are advantageous over live vaccines, RNA/subunit vaccines, and chemically inactivated vaccines mainly due to the complete inactivation of pathogens, and the presence of intact, highly antigenic epitopes. To conclude, this article descriptively highlights eBeam technology’s advantages over other means of vaccine development.

Broiler chicken lameness caused by bacterial chondronecrosis with osteomyelitis (BCO) is presently amongst the most important economic and animal welfare issues faced by the poultry industry, and the estimated economic loss is around USD 150 million. BCO lameness is associated with multiple opportunistic bacterial pathogens inhabiting the respiratory and gastrointestinal tracts. In cases of immune deficiency resulting from stress, injury, or inflammation of the tissue, opportunistic pathogens, mainly Staphylococcus spp., can infiltrate the respiratory or gastrointestinal mucosa and migrate through the bloodstream to eventually colonize the growth plates of long bones, causing necrosis that leads to lameness. This is the first report of developing a Staphylococcus vaccine against BCO lameness disease in broiler chickens. Electron beam (eBeam) technology causes irreparable DNA damage, preventing bacterial multiplication, while keeping the epitopes of the cell membrane intact, helping the immune system generate a more effective response. Our results show a 50% reduction of lameness incidence in the eBeam-vaccinated chicken group compared to the control. Additionally, the eBeam-vaccinated chickens present higher titer of anti-Staphylococcus IgA, signifying the development of an efficient and more specific humoral immune response. Our data establish the eBeam-killed Staphylococcus vaccine as an effective approach to reducing the incidence of lameness in broiler chickens.

Bacterial chondronecrosis with osteomyelitis (BCO) lameness is a major welfare issue for broiler production worldwide affecting approximately 1.5% of broilers over 42 days old. Excessive body weight gain causes mechanical stress on long bones, leading to micro-fractures. This condition induces a bacterial infection of fractures, resulting in bone necrosis and eventual BCO lameness. Increasing gut integrity and supporting Calcium metabolism contribute to the optimal bone structure and subsequently reduce BCO lameness. Probiotics thus provide an excellent strategy for alleviating BCO due to the improvement of intestinal integrity and barrier function. Accordingly, the present study investigated the lameness reduction through the feed supplementation of a selected probiotic. Broiler chickens were assigned to three treatments, including a control litter group (FL), a PoultryStar^®Bro probiotic fed group (BRO), and a control wire-flooring group (CW) designed to induce BCO lameness. The probiotic significantly decreased lameness by 46% compared to the control group (p < 0.05). The most predominant bacteria identified from the BCO lesions were Staphylococcus cohnii and Staphylococcus lentus. Moreover, significant increments of tight junction gene expression in jejunum and ileum, plus numerical improvements of body weight gain (BW; +360 g) and feed conversion ratio (FCR; −12 pts) were observed in BRO-supplemented birds.

Bacterial chondronecrosis with osteomyelitis (BCO) is caused by several bacteria, including Salmonella, Staphylococcus spp., Escherichia coli, Enterococcus spp., and Mycoplasma spp., and BCO is a significant animal health and welfare issue in broiler production, causing 1–2% of bird condemnation at marketing age and resulting in annual losses of tens of millions of dollars. This study evaluated the efficacy of a probiotic program alone and combined with a multivalent electron beam (eBeam)-inactivated vaccine in reducing BCO lameness. The probiotic program included an Enterococcus faecium spray (E. faecium 669, at 2 × 10⁹ CFU/bird) at hatch and a triple-strain Bacillus-based product (B. subtilis 597, B. subtilis 600, and B. amyloliquefaciens 516 at 1 × 10⁹ CFU/bird/day) in drinking water from day 1 to day 56. An aerosol transmission challenge model simulated commercial bacterial exposure. Birds were divided into five groups: a positive control (PC) group (T1) and a negative control (NC) group (T2) receiving no treatment and three treatment groups receiving the probiotic program (T3), the multivalent vaccine (T4), or both the probiotic program and the multivalent vaccine (T5). Data analyzed via ANOVA (p < 0.05) showed T3, T4, and T5 had significantly lower lameness (43.7%, 40.3%, and 40.7%) than T2 (71.0%) and T1 (83.0%). T5 resulted in reductions comparable to T4, indicating no significant synergistic effect. These findings show that probiotics alone or with a vaccine effectively mitigate BCO lameness, enhance broiler welfare, and reduce economic losses.

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.