Research on oligochitosan production by gamma radiation degradation techniques in pilot scale for application in disease control and growth performance of chickens

Degradation of chitosan to prepare the low molecular weight chitosan has been carried out by gamma irradiation of chitosan in H₂O₂ solution. The effects of radiation dose, dose rate, ratio of CTS:H₂O and H₂O₂ concentration to the degrading efficiency of chitosan have been investigated. The obtained results showed the chitosan molecular weight reduced with the increase of radiation dose. Chitosan was irradiated at radiation dose 10 kGy in the presence of H₂O₂ 1% its molecular weight achieved 45 kDa. The effect of irradiated chitosan on the growth development and the survival ratio of breeding chickens in the process were also studied. The results shown that low molecular weight chitosan supplement in diets had positive effect of the resistant ability, growth performance and reduced chick mortality. With supplement ratio of 100 mg/kg diets, chitosan 45 kDa had positive affect on growth performance of chicks, the weight of chickens increased 6% and survival ratio was 94.8% while the normal survival ratio was only 92.6%. (author)