Preparation And Effect On Immune Efficacy Of Coccidium Vaccine Diluent

In order to change the increasing vaccine cost and the poor immune efficacy caused by double dose and inhomogeneity of Immunization in the drinking water, we experimented with the followings:(1) By means of the study of suspension liquid suspension mechanism, coccidium immunomechanism, adjuvant effect mechanism and the static settling experiment, we selected out the suspending agent which could make coccidium well-distributed suspension in the water.(2) By means of the orthogonal experiment of first immunization and secomd immunization, we selected out the coccidium vaccine adjuvant which could shortening the period of immunity.(3) By means of a series of experiments of coccidium vaccine diluent dissolution, we developed the lowcost, convenient and dissolving instantly coccidium vaccine diluent. The results show that:(1) The screening of coccidium vaccine suspending agentThe efficacy of suspending was better and the liquidity of suspending was poorer with the increasing of the concentration of carbomer and hydroxypropyl (HPMC). In the orthogonal experiment of2levels and4factors, the range of carbomer was93.34and the range of HPMC was29.59. The results show that carbomer is more efficient to the efficacy of suspending. Synthesizing the efficacy of suspending, the wall deposition and the cost, the level and factor of A3B4conforms to the pharmacopoeia of China, and it is the most cost-effective which can make the coccidiosis settling3.33%for6h and has1.61%the wall deposition rate.(2) The screening of coccidium vaccine adjuvantIn the first-immunization and challenge-infection experiment, the relative weight gain rate, the reduction of lesion scores (RLS) and the oocyst decrement rate of the adjuvant (astragalus polysaccharide, chitosan, glucose)-immunization group were higher and its average lesion score was lower than the immunization group’s. Astragalus polysaccharide was the most effective to the relative weight gain rate and its range R was3.25%. The range R of chitosan was2.23%and glucose’s was0.16%. Astragalus polysaccharide was the most effective to the oocyst decrement rate and its range R was17.31%. The range R of glucose was7.91%and chitosan’s was2.13%. Astragalus polysaccharide also was the most effective to lesion score and its range R was0.4%. The range R of chitosan was0.16%and glucose’s was0.04%. Discovered through comparative analysis, the level and factor of A2B2C2was the best.(3) In the drinking-water for4h experiment, the coccidium vaccine adjuvant group had no effect to chicken on drinking water and its relative drinking water volume was105.89%of the drinking water control group.(4) The effect of the vaccine adjuvant on the immune appearing stage of the coccidium vaccineIn the immune appearing stage of first immunization experiment, the adjuvant group is better than the immunization group, and its relative weight gain rate was77.9%, the average lesion score was1.2, the oocyst decrement rate was69.5%and RLS was66.7%, whereas the immunization group’s relative weight gain rate was74.9%, the average lesion score was1.6, the oocyst decrement rate was65.1%and RLS was55.6%on the8th day after first immunization. The adjuvant group is better than the immunization group, and its relative weight gain rate was78.2%, the average lesion score was1.1, the oocyst decrement rate was72.8%and RLS was68.4%, whereas the immunization group’s relative weight gain rate was76.2%, the average lesion score was1.5, the oocyst decrement rate was68.7%and RLS was58.3%on the9th day after first immunization. All data of the adjuvant group were significantly lower than the immunization group (P<0.01), showing it had good efficacy on megadose challenge infection. However, it failed to the standard cause its average lesion score was>1and relative weight gain rate didn’t attain to80%.In the immune appearing stage of second immunization experiment, the relative weight gain rate was85.0%, the average lesion score was1.0, RLS was71.4%and the oocyst decrement rate was83.4%on6th day and the relative weight gain rate was89.2%, the average lesion score was1.0, RLS was77.8%and the oocyst decrement rate was88.7%on7th day after second immunization in the adjuvant group, showing it attain to good immune efficacy and shorten the immune appearing stage when adding the adjuvant.(5) It shortened the dissolving time to4min when adding the surfactant20%poloxamer188in the coccidium vaccine adjuvant. Meanwhile, the sedimentation rate of coccidiosis was3.33%in6h. When used10%,20%and30%water to dilute, the coccidium vaccine adjuvant could dissolve in5to7min and present pasty. With the more water add, the liquidity was better. When used40%,50%and100%water to dilute, the coccidium vaccine adjuvant was could dissolve in4to7min and present transparent and light brown. With the more water add, the liquidity was better. When used20%water or more to dissolve, the adjuvant could dissolve in5min and had good liquidity. The best water temperature is17to31℃and the dissolving time is5to6min for the coccidium vaccine adjuvant.