Screening Of Zinc-rich Microorganisms And Its Biological Efficiency For Chicken

Zinc is an important essential trace element in the body,and it has the ability to promote animal growth,improve immunity and fertility.Zinc-rich probiotics have the dual effects of organic zinc and probiotics,such as low toxicity,high absorption and utilization,anti-oxidation,small environmental pollution,etc.Therefore,the discovery of probiotics that can efficiently convert inorganic zinc into organic zinc is currently the focus of research..In this study,a strain of Saccharomyces cerevisiae that can efficiently transform inorganic zinc was screened out,and the optimal culture conditions for transforming inorganic zinc were optimized using inorganic zinc concentration,culture temperature,culture time,and inoculum volume of bacterial culture.The best combination of parameters was determined.In addition,the biological titers of the preferred brewer's yeast zinc-fed chickens were also assessed.Experiment 1.Selection of Zinc-enriched Microorganisms and Optimization of Their Culture ConditionsThe purpose of this experiment is to screen out a microorganism capable of efficiently converting inorganic zinc into organic zinc,and study the optimal conditions for the conversion of inorganic zinc into microbial organic zinc.First of all,16 strains of existing feed microorganisms in the laboratory were screened for high conversion rates of inorganic zinc,and then single factor experiments were used to design inorganic zinc concentrations,incubation temperatures,and cultures that affect the transformation of inorganic zinc by microorganisms.The factors such as time and inoculum volume were optimized,and orthogonal optimization was performed on this basis to screen the best combination parameters of inorganic zinc concentration,culture temperature,culture time,and inoculum volume of the bacteria solution.The results showed that the No.58 Saccharomyces cerevisiae had the highest conversion efficiency of inorganic zinc to organic zinc,with inorganic zinc concentration of 2mg/L,bacterial liquid inoculation of 4%,and cultivation at 28°C for 66 hours.The Saccharomyces cerevisiae transformed inorganic zinc.The best effect is up to 98.01%.This shows that No.58 Saccharomyces cerevisiae has good prospects for the development of microbial organic zinc.Experiment 2.Bioavailability of Zinc-enriched Yeasts in Breeding of RoostersIn order to evaluate the effect of yeast zinc produced in this experiment in animals,1.8 kg of healthy adult cocks were selected as experimental animals and divided into two groups,a control group and a test group,in which the control components were two groups(1 and 2).The test group were two groups(1 and 2)with 5 chickens in each group for a total of 20 chickens.The control group 1 was fed with a zinc content of 60 mg/kg,and the control group 2 was fed with a zinc content of 90 mg/kg;the test group 1 was fed with yeast zinc 60 mg/kg,and the test group 2 was fed with yeast zinc 90 mg/kg.Feed for 10 days,with a prefeed period of 5 days and a formal period of 5 days.From the official period,fecal urine was continuously collected for 5 days,and each chicken was collected separately.The results showed that the apparent metabolizability of dry matter in the organic zinc-zinc group at the same zinc level was significantly higher(P<0.05)than that in the inorganic zinc group,and the apparent metabolic rate of crude protein was significantly(P<0.01)higher than that of inorganic zinc.In the diets with a zinc level of 60 mg/kg,the apparent apparent metabolic rate of the organic zinc group was significantly higher(P<0.05)than that of the inorganic zinc group;when the zinc level was 90 mg/kg,the organic yeast was The crude fat and energy metabolism rate of the zinc group was significantly higher than that of the inorganic zinc group(P<0.01).The organic yeast zinc group had no significant effect on the metabolic rate of crude ash(P>0.05),and 60 mg/kg organic zinc yeast had no significant effect on the apparent metabolic rate of energy(P>0.05).The relative bio-value of zinc in zinc-rich yeast relative to zinc in inorganic zinc sulfate is 114.83%.The results indicate that zinc-rich yeast can be used as an organic zinc additive for chicken diets.