Coccidiosis: Recent Progress in Host Immunity and Alternatives to Antibiotic Strategies

Abstract

Coccidiosis is an avian intestinal disease caused by several distinct species of Eimeria parasites that damage the host’s intestinal system, resulting in poor nutrition absorption, reduced growth, and often death. Increasing evidence from recent studies indicates that immune-based strategies such as the use of recombinant vaccines and various dietary immunomodulating feed additives can improve host defense against intracellular parasitism and reduce intestinal damage due to inflammatory responses induced by parasites. Therefore, a comprehensive understanding of the complex interactions between the host immune system, gut microbiota, enteroendocrine system, and parasites that contribute to the outcome of coccidiosis is necessary to develop logical strategies to control coccidiosis in the post-antibiotic era. Most important for vaccine development is the need to understand the protective role of the local intestinal immune response and the identification of various effector molecules which mediate anti-coccidial activity against intracellular parasites. This review summarizes the current understanding of the host immune response to coccidiosis in poultry and discusses various non-antibiotic strategies which are being developed for coccidiosis control. A better understanding of the basic immunobiology of pertinent host–parasite interactions in avian coccidiosis will facilitate the development of effective anti-Eimeria strategies to mitigate the negative effects of coccidiosis.

Effects of phytase and coccidial vaccine on growth performance, nutrient digestibility, bone mineralization, and intestinal gene expression of broilers

“…Coccidial vaccines can mitigate negative effects of coccidiosis by enhancing immunity of the birds with low dose exposure of Eimeria oocysts ( Chapman et al, 2002 ; Chapman, 2014 ). However, they may lead to sub-clinical infection and potential growth reduction in early period (2 wk following vaccination), which is often associated with mild intestinal inflammation and oxidative stress as a result of damage to bird intestinal epithelium ( Li et al, 2005 ; Cervantes, 2015 ), resulting in nutrient malabsorption, enhanced immune response and decrease in the expression of brush-border membrane nutrient transporters ( Paris and Wong, 2013 ; Su et al, 2014 ; Lee et al, 2022 ). Moreover, the coccidial vaccination is reported to induce the incidence of bacterial enteritis ( Williams, 2002 ).…”

Inhibitory effect of morin on aldolase 2 from Eimeria tenella

“…Coccidiosis is one of the most critical diseases in chickens ( Blake et al, 2020 ; El-Shall et al, 2022 ; Lee et al, 2022 ) caused by the coccidian parasites Eimeria species infecting the intestinal epithelial cells of chickens. Eimeria species have a worldwide distribution and seriously harm the chicken industry, resulting in substantial economic losses (El- Liu et al, 2020 ).…”

CircDCLRE1C Regulated Lipopolysaccharide-Induced Inflammatory Response and Apoptosis by Regulating miR-214b-3p/STAT3 Pathway in Macrophages

“…Eimeria is parasitic protozoa that cause chickens’ intestinal tissue to become inflamed and bleed easily after invasion, inducing the host’s innate and adaptive immunity [ 23 , 24 , 25 ]. Macrophages can be activated by a variety of stimuli, such as parasites, lipoproteins, viruses, and other microorganisms, and are known for their key roles in the immune response [ 26 ].…”