Cloning, expression and purification of Eimeria maxima gametocyte antigen-EmGam56 for control of poultry coccidiosis.

Poultry coccidiosis is an important devitalizing enteric protozoan disease caused by a group of obligatory intracellular apicomplexan parasites of the Genus Eimeria contributing to major economic loss in commercial poultry worldwide. As the current method of chemotherapeutic control using ionophores in feed had led to development of drug resistant isolates, the need for development of prophylactic vaccines is the most viable alternate and eco-friendly control strategy as on date. Of the several candidate vaccines, the EmGam 56 is one of the most promising candidates which protect the birds against E. maxima, E. tenella and E. acervulina, the three most pathogenic coccidian species infecting commercial chicken. EmGam56 is a major wall forming component of macrogametocyte of E. maxima and a candidate with high immunogenicity and low virulence. The present study was planned and carried out for the generation of E.coli expressed recombinant gametocyte antigen-EmGam56 using pET 28(a+) as cloning vector and BL21 DE3 (pLysS) as prokaryotic expression system in a Bio-fermentor (New Brunswick™ Scientific BioFlo 310). The recombinant protein was purified by conventional (Ammonium sulphate precipitation) and by automatic purification system (AKTA prime) in Ni-NTA column for a planned immunization trial with experimental chickens.

Site-specific delivery of green tea coated aluminium magnesium silicate beads and studies on their effect against chicken coccidiosis.

In this report, the site-specific co-delivery of green tea/aluminium magnesium silicate (AMS) was reported and the specific target delivery was achieved orally. The new co-precipitation process was developed to synthesis the green tea/AMS hybrid complex and using energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy and Raman confirmed its successful synthesis. The blood biocompatibility of the green tea/AMS was tested using chicken blood, and the compound is safe up to 500 mg/ml. After mixed with hydroxypropyl methylcellulose phthalate, the oral beads were synthesised using a linking agent. The oral beads underwent different pH-based dissolution studies and the results indicated that the beads specifically dissolved in gastric pH (6.5). The pharmaco kinetic studies were performed to estimate the delivery kinetics. The results revealed that the beads underwent as per the Higuchi model. The anticoccidial effects of the beads were tested using chicken. The animal studies were performed in two different modes such as prophylactic treatment and active treatment after Eimeria species challenge. The results indicated that the prophylactic treatment with beads 100% protected the chicken and the active treatment with beads after the Eimeria challenge significantly protected against the intestinal damage and it also enhanced the anticoccidial effect.