| Lactic acid bacteria are a type of gram-positive bacteria that can produce lactic acid by using fermentable carbohydrates.They are widely present in the intestinal tract of animals.At present,many lactic acid bacteria have been used in studies of monogastric animals.The lactic acid bacteria in the intestinal Metabolites such as hydrogen,lactic acid,and organic acids.Reduce intestinal p H,adjust the balance of intestinal flora,achieve the effect of improving the body’s health and improving growth performance.Research on the application of lactic acid bacteria in ruminants is mainly focused on the regulation of rumen flora.There are few direct studies on the effect of lactic acid bacteria on the posterior intestine of ruminants,in order to explore whether the lactic acid bacteria in the posterior intestine of ruminants can function like monogastric animals..The laboratory-coated Lactobacillus plantarum(LP-115)micro-capsules were fed to perinatal dairy cows,and their effects on the digestibility,production performance and serum biochemical indexes of dairy cows were explored.This test adopts a single factor test design.The entire test period is 42 days.It was carried out on a large modern intensive dairy farm in eastern Heilongjiang Province.The expected delivery date(21±3d),health,body condition,and parity were the same(first parity).)8 Holstein cows were randomly divided into test group and control group,each group had 4 replicates,and each replicate had 1 cow.During the experiment,the cows were fed freely,freely drinking water,and reared in a loose pen.Each cow in the experimental group was fed 3g of coated lactic acid bacteria(the number of viable bacteria was 3.4×10~9CFU/g)per day,and the control group was fed the same amount of coating material.The dairy cows were fed with lactic acid bacteria by gavage every morning at 6:00.Feeding starts from 21 days before delivery to 21 days after delivery.Milk and serum samples were collected at 1 d,7 d,14 d,and 21 d after delivery,and milk and serum samples were collected before morning feeding,and feed samples and feces were collected in the last week of the experiment.Determine feed apparent digestibility,milk composition and serum biochemical indicators.At the same time,the milk production of the experimental cows was recorded.The experimental results are as follows:Rumen bypassed lactic acid bacteria micro-capsule preparations significantly improved the apparent digestibility of CP and crude fat in diets(P<0.05),which increased by 6.83%and 4.27%,respectively.However,it had no significant effect on the apparent digestibility of NDF,ADF and crude ash in the diet(P>0.05).Feeding lactic acid bacteria preparations significantly increased the milk production of dairy cows(P<0.05),and significantly increased the total milk solids content of dairy cows on the 14th day after delivery(P<0.05),increasing by 2.09%and 1.27%respectively.At 14 days postpartum,the milk somatic cells of dairy cows in the rumen-fed lactic acid bacteria microcapsule group decreased significantly(P<0.05),and the number of somatic cells decreased from 503,300 cells/ml to 380,000 cells/ml.In the rest of the time,the test indicators were not significantly affected(P>0.05).On the day of cow production,there was no significant difference in blood biochemical indicators between the rumen-fed lactic acid bacteria micro-capsule group and the control group;on the 21st day after delivery,the rumen-fed lactic acid bacteria preparation significantly increased the blood total protein and globulin content(P<0.05)),which increased by 8.63IU/L and 6.75IU/L respectively.Reduced the level of urea nitrogen(P<0.05),from 6.94mmol/L to 5.94mmol/L.There was no significant difference in other indicators(P>0.05).To sum up,feeding the rumen lactic acid bacteria preparations to dairy cows significantly improves the apparent digestibility of crude fat and CP in the diet;significantly increases the milk production and total solids content of the perinatal dairy cows,and improves the milk to a certain extent.Quality,reducing the number of milk somatic cells.Increase the content of serum TP and GLB in perinatal dairy cows and reduce the content of BUN. |
