Incidence of Bacterial Chondronecrosis with Osteomyelitis Lameness in Commercial Duck Flocks in Mojokerto, Indonesia.

Bacterial Chondronecrosis with Osteomyelitis (BCO) lameness is an infection of opportunistic bacteria in the structural skeletal bones impacting multiple animal species, particularly poultry species. BCO lameness results in significant financial losses to industrial poultry production and increases the risk of foodborne illnesses, posing a major threat to consumers' food safety. As BCO lameness is an inherent risk of fast body weight gain in poultry species, especially broiler chickens, abundant studies have been conducted in broilers and turkeys. Nevertheless, BCO lameness incidence in ducks remains elusive. Thus, this is the first survey investigating the prevalence of BCO lameness cases in ducks. The survey was conducted in commercial duck farms in Indonesia, the fourth biggest duck-producing country globally. Two hundred birds from four commercial duck farms in Mojokerto, East Java, Indonesia, were necropsied to examine their lameness lesions in the femoral head and proximal tibia. Of the 44% birds showing BCO lameness lesions, 3% were evidently clinically lame birds, particularly exhibiting limping gait. Femoral head separation (FHS) and tibial head necrosis (THN) are the most frequently observed lesions in ducks, representing a mild-to-moderate BCO lameness state. Based on the results of this study, intervention measures to boost the immune system and skeletal bone integrity of ducks are urgently required.