Screening The Proportion Of Compound Acidifier And The Affect On Gastrointestinal Digestion Sludge Of Weaned Piglets In Vitro

This test is composed of three small experiment. The purpose of this test is to find the reasonable proportion of acidifier to offer help and provided a scientific basis to alternative antibiotics, through this test to reaveal the mechanism of acidulant in piglets.On the basis of this to make recommendations on normative development of acidifier and guide the production practice.Test one:The screening of best compound acidifiers. The test use lactate(phosphate), citric acid (fumarate) and benzoic acid by 3 x 3 factorial design are configured to lactate mixed compound acidifier (lactate-citric acid-benzene; lactate-fumarate-benzene) and phosphate mixed (phosphate-citric acid-benzene; phosphate-fumarate-benzene) compound acidifier to study the features of compound acidifier research, under the condition of different ratio of piglet diet after adding compound acidifier of pH and the change of the acid binding force, choose the optimal combination.The determination of the optimal compound acidifier buffering capacity, slow-release ability, and diet to join compound electrolyte balance after acidifying agentTest two:The bacteriostatic test in vitro of compound acidifier.Through the plate punching method measuring the minimum bacteriostasis diameter,96 orifice plate to measure the minimum bacteriostasis concentration to study the compound acidifier in e. coli, salmonella, and the inhibitory effect of staphylococcus aureus.Test three: Experiment in vitro digestion. With adding different acidulants piglet diet in set specific pH simulation pig gastric juice and intestinal juice, according to the requirement of the different stages of weaning day-old test set different digestion conditions.Determation of the pH value of the gastric chyme after digestion and the small intestine chymus of dry matter, crude protein digestibility and the content of volatile fatty acid butyrate. The experimental results showed that:1. The best adding proportion of lactate-citric acid-benzene is (50%,20%,50%); lactate-fumarate -benzene (50%,20%,10%); phosphate-citric acid-benzene is (50%,10%, 50%); phosphate-fumarate-benzene is (50%, 10%, 50%). Four kinds of compound acidifier buffer capacity, slow-release ability difference was not significant (p>0.05). Diet electrolyte balance with the increase of concentration of compound acidifier add a decline (P＜0.05), with 0.1%phosphate-fumarate-benzene,0.3%lactate-fumarate-benzene,0.5%phosphate-fumarate-be nzene has the most obvious reduce the effect of diet electrolyte balance (P<0.05), but for the electrolyte balance of the lower level in line with the scope of weaned piglets growth needs, will pose no damage to normal electrolyte balance diet.2. The four kinds of compound acidifier on common bacteria all have better inhibition effect. The lactate-citric acid-benzene and lactate-fumarate-benzene compound acidifier bacteriostatic effect on e. coli is the most obvious (P＜0.05); phosphate-citric acid-benzene compound acidifier bacteriostatic effect on staphylococcus aureus has a best effect (P<0.05); phosphate-fumarate-benzene compound acidifier on e. coli and salmonella has a best inhibition effect (P<0.05). lactate-citric acid-benzene and lactate-fumarate -benzene acidulant minimal inhibitory concentrations (mic) to e. coli were 6.25 mg/mL,12.5 mg/mL; phosphate-citric acid-benzene compound acidifier of staphylococcus aureus minimum bacteriostatic concentration of 6.25 mg/mL, bacteriostatic concentration of e. coli were 12.5 mg/mL; phosphate-fumarate-benzene compound acidifier of e. coli minimum bacteriostatic concentration of 12.5 mg/mL, four kinds of compound acidifier were highly sensitive to three common and harmful bacterium.3. With the increase of concentration of compound acidifier, gastrointestinal digestive residue in the pH value decreased obviously (P<0.05).Adding 0.5% phosphorus rich benzenoid acidulant on different day age after weaning piglets digestion in the stomach residue better effects of lower pH (P<0.01), adding 0.5% phosphate-citric acid-benzene; acidulant for 1 day, 5 days after weaning of small intestine digestive residue low pH have a significant effect (P<0.05).4. The compound is added in the piglet feed acidulant, can significantly improve piglets intestinal digestion rate of dry matter in sludge digestion (p<0.05), and with the increase of concentration of added, in the digestion rate of dry matter (P＜0.05).1 days after weaning, adding 0.5% lactate-citric acid-benzene acidifying agent can significantly improve piglets intestinal digestion rate of dry matter in sludge digestion (P＜0.05), and the effect is better than in 5,12,19 days to add compound acidifier.5. Compound acidification agent is added in the weaned piglets material can significantly improve piglet intestine digestive residue in the crude protein digestibility (P＜0.05), and with the increase of concentration of added, the crude protein digestibility increased(P< 0.05).Adding 0.5% phosphate-fumarate-benzene acidulant on different day age after weaning piglets intestine digestive residue in the crude protein digestibility is significantly increased (P <0.05), and the effect of 1 days after weaning is most obvious (P＜0.05).6. Compound acidifying agent can significantly improve piglets intestinal digestion butyric acid content in the residue (P＜0.05), and with the increase of concentration of added have a rising trend (P<0.05), but with the increase of weaning age, butyric acid content showed a trend of gradual decline (P<0.05).Add 0.5% lactate-citric acid-benzene acidification agent can significantly increase 1 day, 5 days after weaning of butyric acid content in the small intestine digestive residue (P<0.05).