Mycotoxicosis and oxidative stress in poultry: pathogenesis and therapeutic insights

'Unavoidable pollutants', 'natural poisons', 'invisible thieves', and 'silent killers' are the popular names of a group of fundal metabolites, mycotoxins, and the disease caused by these toxins is referred to as mycotoxicosis. In poultry, this disease usually occurs when mycotoxins-producing fungi grow on grain and feed. Although more than 500 different mycotoxins have been identified, scientists have focussed only on mycotoxins of medical and agricultural concern, which are found to be toxic. The pathogenesis and therapeutics of mycotoxicosis in poultry production remain essential challenges. Oxidative stress is a driving force in the pathogenesis of mycotoxicosis. Oxidative stress induces cellular and nuclear damage and mitochondrial dysfunction through the overproduction of reactive oxygen species and reactive nitrogen species. Furthermore, mycotoxins induce ribosomal stress that activates multiple cellular pathways, such as nuclear transcription factor κβ and mitogen-activated protein kinase. Activation of these aberrant cellular signalling pathways and oxidative stress triggers a cascade of pro-inflammatory cytokines, which contributes to apoptosis and tissue/organ dysfunction, such as immunosuppression, hepatotoxicity, nephrotoxicity, neurotoxicity, and gastrointestinal tract toxicity. The consequences of this toxicity lead to poor feed conversion, feed refusal, poor growth rate, reduced fertility, and reduced hatchability of poultry. Therefore, optimally, a better understanding of the disease pathogenesis and oxidative stress is needed to identify specific and targeted therapeutic approaches to combat mycotoxicosis in poultry. This review describes the pathogenesis of mycotoxicosis with particular emphasis on oxidative stress in poultry. This also paves the way for preventive and therapeutic approaches aimed at limiting oxidative stress that can enhance growth, fertility, and production in poultry.