Kinky back is a complex syndrome mostly affecting broilers with some episodes in turkeys as well, defined in medical terms as Bacterial Chondronecrosis with Osteomyelitis (BCO). The rapid growth of heavy birds during the first phase of life is often accompanied by an inadequate skeleton’s development. This may result in skeletal disorders and the development of BCO lesions primarily located at the flexible thoracic vertebra (T4), the proximal head of the femora, and of the tibiae. A common symptom is a lameness, causing feed intake reduction starting at 3 weeks of age and subsequent lower body weight gain and up to 5-7% mortality.
Kinky back is not an infectious disease but commensal pathogens are commonly observed at the lesion level causing infections. The reason for these infections is the pathogenesis of the syndrome: mechanical stress causes several micro-fractures and clefts in cartilages and bones, with subsequent local ischemia and necrosis, and disruption of the endothelial lining, finally favoring blood-borne bacteria colonization, infections, and abscesses formation. The opportunistic pathogens isolated in BCO are Staphylococcus spp., E. coli, and Salmonella spp., but Enterococcus cecorum is the most frequent one.
E. cecorum is a Gram-positive, facultatively anaerobic coccus, component of the normal intestinal microbiota of mammals and birds. This pathogen is spread in the environment through the feces and birds are colonized by oral ingestion within 7 days from the hatch. Gastrointestinal functions and microbiota can be modified by heat stress, changes in the diet, immunosuppression, and infections. When intestinal inflammation occurs, epithelial tight junctions integrity is disrupted, with the alteration of gut mucosa permeability. Leaky tight junctions provide paracellular passages so that bacteria can cross the cellular monolayer and reach the bloodstream causing systemic infections. A peculiarity of E. cecorum is its predilection for cartilages and bones, resulting in abscesses and kinky back syndrome in poultry.
Antibiotic treatment is possible but, in most cases, symptoms are minimally reduced. Moreover, antibiotic resistance and pathogenicity are constantly increasing in E. cecorum strains and field-isolated, making prevention and treatment even less effective. The best approach to this pathology is a coordinated approach to prevention, which includes special attention to housing conditions, litter humidity, and environmental stress, to minimize the mechanical stress to the immature skeleton of chickens and bacterial proliferation. Also diet composition, and in particular vitamin D and minerals, play an important role in bone structure development.
The key to a new approach to kinky back might be the use of nutrition to maintain a well-balanced intestinal microflora and mucosa functionality while keeping at minimum local inflammation. AviPlus®P is a feed additive useful for this purpose: it is specially designed to exploit the synergistic effect of organic acids and nature identical compounds. As antimicrobials, AviPlus®P active ingredients have different but complementary modes of action: organic acids passively enter the bacterial cells with both bacteriostatic and bactericidal activity, while nature identical compounds create pores in the bacterial membrane with a direct bactericidal effect, facilitating the entry of organic acids. The peculiar microencapsulation technology of AviPlus®P ensures the release of its ingredients all along the intestinal tract, where the most microbial colonization occurs. Furthermore, both organic acids and nature identical compounds have anti-inflammatory properties. AviPlus®P improves animal intestinal health enhancing the mucosal barrier function and epithelial integrity, key elements to control bacterial translocation.For more information: marketing@vetagro.com