Reduction of Lameness in Poultry: Could Probiotics Have an Impact?

New research from the University of Arkansas reveal that the prophylactic feeding of a probiotic to broilers reduced significantly the incidence of lameness, according to Michaela Mohnl, product manager for probiotics at Biomin Holding GmbH.

6 January 2012

4 minute read

Lameness is a growing problem in modern poultry. It affects mobility of the animal and is usually related with pain. Lameness will cause animals to suffer and limit their natural movements probably reducing feed and water intake.

Leg disorders and lameness adversely affect the performance and wellbeing of poultry and increase morbidity and mortality. Lameness has several causes in poultry including viral infections of soft tissues, bacterial infections of skeletal and soft tissues and skeletal deformities.

Most common cause of lameness in commercial broilers is bacterial chondronecrosis with osteomyelitis (BCO) formerly known as femoral head necrosis. The term BCO encompasses necrotic degeneration and microbial infection primarily within the proximal heads of the femur and tibia.

Femoral head necrosis/BCO is caused by bacteria that reach the joints via the blood vessels that penetrate the bone to nourish the bone and the cartilage. Bacteria can be transmitted from breeder parents, contaminated egg shells or hatchery sources or enter via the respiratory system or gastrointestinal tract.

How could probiotics have an impact on the incidence of lameness? Enteric bacteria can translocate from the intestine and migrate into the systemic circulation. Once these bacteria reach the circulation they can reach capillaries that irrigate the bone. Probiotics theoretically might interfere with the development of osteomyelitis by attenuating intestinal populations of pathogenic bacteria improving gut health to reduce bacterial leakage (translocation) across the gut wall and priming the immune system to better eliminate translocated bacteria.

Intestinal protection by means of probiotic supplementation could lead to fewer bacteria reaching the articular surface reducing the incidence of femoral head necrosis. In order to study the development of lameness a wire flooring model for inducing lameness in broilers was developed by a group of researchers under the direction of Professor Wideman at the Department of Poultry Science, University of Arkansas.

Growing broilers on wire flooring provides an excellent experimental model for reproducibly triggering significant levels of clinical lameness attributable to osteochondrosis and osteomyelitis of the proximal femur and tibia. Leg disorders and lameness are commonplace when broilers are reared in cages with wire flooring due to high stocking density and lack of exercise.

A series of 4 independent experiments was carried out at the Poultry Research Farm. The objective of these studies was to evaluate the efficacy of a host-specific multi-species probiotic (PoultryStar®, Biomin GmbH) as a prophylactic feed additive for preventing the onset of lameness in broilers by using the wire flooring model for inducing lameness in broilers.

Overall, the multi-species probiotic apparently delayed the progressive deterioration of early lesions into the grossly degenerative abscesses that are associated with terminal lameness in broilers. Theoretically the probiotic reduces the development of clinical lameness by interfering with bacterial translocation into sub-clinically damaged voids or clefts in the proximal femoral and tibial epiphyseal plates.

Adding the multi-species probiotic PoultryStar to the diet consistently reduced the incidence of lameness for broilers reared on wire flooring in four statistically significant experiments. These experiments indicate that bacterial translocation from the gastrointestinal tract is likely to be a significant route contributing to hematogenous infection. The multi-species probiotic administered prophylactically can provide a plausible alternative to antibiotics for reducing the incidence of BCO.