Effects Of Maize Gelatinization Processing And Urease Inhibitor On The Utilation Of Urea Nitrogen In Goats

In order to improve the utilation efficienty of urea in ruminants, corn gelatinization techniques was selected to get the optimum corn product. Then studied the effects of gelatinized corn and hydroquinone on utilation efficienty of urea using in-vitro culture techniques and molecular biology techniques. And then confirm the effect using in-vivo experiment. The main results were listed as follows:Experiment 1. Three factors (corn particle size, reaction temperature and reaction time) and five levels for each are selected for quadratic regression orthogonal rotation test. Corn particle sizes are 6, 10, 20, 40 and 60 mesh respectively, the reaction temperatures are 75℃, 80℃, 85℃, 90℃, 95℃respectively and the reaction times are 10min, 13 min, 16 min, 19 min, 22 min respectively. When corn to water ratio was 1:7, 60 mesh corn gelatinizated for 18.13 min under 88.96℃, the corn gelatinization degree can reach maximum (51 %). The results showed that corn particle size, reaction temperature and reaction time had significant effects on gelatinization degree and the interaction effects between corn particle size and reaction temperature were also significant (P<0.05).Experiment 2. Chinensis, soybean meal, gelatinized corn, urea and hydroquinone were selected for in-vitro culture experiment. Using urea instead of 1/3 crude protein and gelatinized corn instead of common corn, we chose hydroquinone amount level at 50 mg/kg (dry matter) to study the parameters of rumen environment and the effect of gelatinized corn and hydroquinone on the amylolytic bacteria through molecular biology techniques. The results showed that gelatinized corn and hydroquinone had no siganificant effect on rumen pH and volatile fatty acids (VFA) content (P>0.05), but they had siganificant effects on reducing rumen ammonia concentration and increasing bacterial protein synthesis (P<0.05). We also found that gelatinized corn and hydroquinone had siganificant effects on promoting growth and reproduction of habitats rumen bacteria and ruminobacter amylophilus (P<0.05).Experiment 3. In order to study the effect of gelatinized corn and hydroquinone on rumen environment parameters, blood urea nitrogen and nitrogen balance, four Xuhuai goats for 4×4 Latin square experiment were selected. The goats'diets are the same as the in-vitro culture substrate. The results showed that gelatinized corn had no siganificant effect on rumen pH, VFA, rumen urea nitrogen value and blood urea nitrogen(P>0.05), but it significantly reduced ammonia concentration and increased bacteria protein synthesis(P<0.05). The metabolism experiment also confirmed that gelatinized corn and hydroquinone were helpful for nitrogen deposition and the effects were significant(P<0.05).