Preparation Of Functional Egg Yolk Powder And Effect On Growth Performance Of Piglets

The experiments were conducted to investigate whether or not egg yolk antibodies (egg yolk immunoglobulins, IgY) can be used as a functional feed preparation for the prevention and treatment of enteric infection.The specific egg yolk antibodies (IgY) were prepared from eggs of the laying hens immunized with the porcine pathogenic Escherichia coli (ETEC) as antigen. The components, characteristics, and storage stability of the functional egg yolk powder and the effects on the growth performance of mouse and piglet were studied on the basis of the research functional egg yolk antibody powder preparation and spray drying process parameters. The major results were as follows:1. Preparation of IgYIt began to collected the eggs for producing the functional egg yolk powder when the IgY titer was over 1:12800 after the laying hens were the first immunized 40d. Eggs with high antibody titer can be obtained in succession when strengthen the immune every 60d after thefirst immunized 40d.2. Selection of the spray drying process parameters of Functional egg yolk powderOptimum parameters of spray drying for the functional egg yolk powder were selected by the main evaluating indicator such as antibody titer, product yield and sensory properties. The results showed that the temperature of spray-dry tower should be controlled between 140℃~160℃inlet and 78℃~83℃outlet,and clean up the spray drying powder timely. The functional egg yolk powder can be ensured with higher antibody titer and production efficiency, lesser production costs in this way.3. The stability test of functional egg yolk antibody powderFunctional egg yolk powder comply with GB 2749-2003 egg products hygiene standards, which with 1.5% average moisture, total bacterial count 156 CFU/g and E. coli 0 CFU/g. The results indicated that the egg yolk antibody titer was not affected during 5 days of storage under 60℃-dry-heat environment, the antibody titer began to degenerate after 2 days of storage in the hygrothermal and open environment, it can maintain high antibody titer during one year in a room temperature and airtight environment. The shelf life of functional egg yolk powder was one year under atmospheric temperature, dry and closed environment.4. Mouse feeding experimentThe results of mice feeding experiment showed that the specific egg yolk antibodies were effected on the ETEC significant inhibition by in vitro experiments; the functional egg yolk powder can promote the growth performance and immunity regulating of the mice, and play importment role in prevention and treatment the mice enteric infection induced by pathogenic E. coli. The mortality of mice in the experimental group was significantly lower by 52.3% than that of mice in the control group (P<0.05).5. Piglets feeding experimentA 28d-feeding experiment was conducted to determine the effect of functional egg yolk powder on the growth performance and health of weaned piglets.90 weaned piglets(32±2-day-old, after weaning 5d) were selected and randomly divided into three groups, each group was runing in triplicate and 10 each. The control group was fed the basal diet, trial groupⅠandⅡwere fed the diets with basal diet added 0.1% or 0.2% functional egg yolk powder respectively. The results showed that the average daily weight gain(ADWG) of piglets in trial groupⅠandⅡwere significantly higher than that of piglets in control group(P<0.05), raised by 14.4% and 15.3% respectivly; the average daily feed intake(ADFI) of piglets in trial groupⅠandⅡwere higher than that of piglets in control group, increased by 11.70%and 6.86% respectively,and the ratio of feed and weight gain of trial groupⅠandⅡwere lower than that of control group, decreased by 5.55% and 6.50% respectively; the diarrhea rates of piglets in trial groupⅠandⅡwere significantly lower than that of piglets in control group(P<0.01), decreased by 54.8% and 84.3% respectively, and reduced piglet mortality and total fecal Escherichia coli; the cardiac index of piglets in trial groupⅡwas significantly higher by 29%than that of piglets the control group (P<0.05); the blood biochemical parameters and morphology of intestinal villi of the piglets in different groups were not significant difference, but intestinal villi of the piglets in the experimental groups was on the rise trend; the economic efficiency of per piglet in trial groups were significant higher by 67.76% and 86.42%than that of piglets in control group(P<0.01). The finding from this study Show that the functional egg yolk powder can effectively improve the growth performance of piglets, and be prepared to prevent and treat infection the disease of the piglets caused by ETEC, improve the breeding pigs economic and ecological benefits, and has broad application prospects as a feed preparation.