Tibial dyschondroplasia is closely related to suppression of expression of hypoxia-inducible factors 1α, 2α, and 3α in chickens

Tibial dyschondroplasia (TD) cases has not been reported in Tibetan chickens (TBCs), but it is commonly seen in commercial broilers characterized by lameness. The underlying mechanism remains unclear. Hypoxia-inducible factors (HIFs) are important regulators of cellular adaptation to hypoxic conditions. In this study, we investigated the role of HIF-1 alpha, -2 alpha, and -3 alpha in hypoxia and thiram-induced TD and their effect on tibial growth plate development in Arbor Acres chickens (AACs) and TBCs. RNA and protein expression levels of HIF-1 alpha, -2 alpha, and -3 alpha were determined by using quantitative reverse transcriptase polymerase chain reaction and western blotting analyses, respectively. Interestingly, the results showed that HIF-1 alpha, -2 alpha, and -3 alpha expressions in the tibial growth plate of TBCs were upregulated by hypoxia and the change was more significant in TBCs than in AACs. However, these factors were downregulated in thiram-induced TD. To further clarify the effect of thiram on tibial growth plate in commercial broilers, AACs were observed to exhibit more pronounced changes in their growth plate that that in TBCs. Taken together, these results demonstrate that HIF-1 alpha, -2 alpha, and -3 alpha may be important in tibial growth plate development and in the prevention of TD. The present study contributes novel insights on a therapeutic target for poultry TD.