Coccidiosis in domestic chickens: a review of prevention and control strategies

Abstract

Avian coccidiosis is one of the most important and persistent challenges facing the global poultry industry, resulting in reduced productivity due to intestinal damage caused by the intracellular apicomplexan protozoan Eimeria. The life cycle of Eimeria is complex, characterised by intra- and extracellular stages. The intracellular stage induces an inflammatory response partly responsible for tissue damage, haemorrhagic diarrhoea, poor growth, increased susceptibility to other pathogens and, in some severe cases (E. tenella and E. necatrix) high mortality. Good sanitary management is essential to prevent coccidiosis in chickens. The administration of anticoccidials in feed can also effectively reduce the intensity of Eimeria infection. However, their widespread and long-term use has led to the development of resistance to these additives worldwide. Although live non-attenuated and attenuated vaccines have been developed, they have certain limitations. In addition to the traditional methods of prevention and control, phytogenic products are emerging as an alternative and complementary approach to try to control avian coccidiosis. Moreover, the ongoing research on genetic selection and development of recombinant and subunit vaccines against avian coccidiosis is promising for prevention, but their efficacy and adoption in the poultry industry is yet to be proven. In addition, as alternatives to coccidiostats, the use of natural extracts is more accepted by consumers and increasingly being studied. This article therefore presents an overview of the economic impact of coccidiosis in chickens on production and discusses the integrated health strategies for controlling coccidiosis in chickens.