瘤胃保护葡萄糖的制备及在奶牛围产后期的应用研究

发布时间：2018-12-15 05:40

【摘要】：本研究采用流化床包衣技术,研制出在瘤胃内保护率高的葡萄糖微胶囊产品,并将其添加到围产后期奶牛日粮中进行饲养试验。旨在探究日粮中添加葡萄糖对围产后期奶牛体重、生产性能、血液生化指标和营养物质表观消化率的影响。研究分为如下三个部分进行:试验一、壁材及适宜浓度的筛选选取乙基纤维素、聚丙烯酸树脂IV和壳聚糖三种对p H敏感的材料作为壁材,采用相同的制作工艺及制作条件,通过感官指标评定其不同浓度下包衣制粒效果,从而确定各类壁材的最佳浓度。研究表明,乙基纤维素、丙烯酸树脂IV和壳聚糖可在最适浓度下制备出的瘤胃保护葡萄糖微胶囊,颗粒较均匀,包衣完整,样品干燥不易发生粘连。试验二、瘤胃保护葡萄糖微胶囊的制备及其保护效果评定将葡萄糖做为芯材,适宜浓度的乙基纤维素、聚丙烯酸树脂IV和壳聚糖三种对p H材料作为壁材,利用FLP-3流化床制粒干燥机,采用喷雾干燥法制备出三种瘤胃保护性葡萄糖微胶囊,乙基纤维素-M、聚丙烯酸树脂IV-M和壳聚糖微-M。通过体外试验和体内试验,检测三种瘤胃保护性葡萄糖微胶囊在瘤胃中的稳定性。结果表明:在体外培养试验中,乙基纤维素-M微胶囊在人工唾液及p H为6.6的缓冲液中培养2h~24h时,释放率分别为9.5%~15.52%和11.82%~35.69%,极显著低于聚丙烯酸树脂IV-M微胶囊和壳聚糖微-M胶囊(P0.01)。用尼龙袋法进行瘤胃降解率测定,随着时间延长,三种产品的降解率均逐渐升高,但乙基纤维素微胶囊在2h~24h内的释放率仍最低,即乙基纤维素-M微胶囊释放率聚丙烯酸树脂IV-M微胶囊壳聚糖-M微胶囊(P0.01)。在瘤胃中的释放率为26.68%~48.62%,有效保护率达57.42%(k=0.03)。可见在本试验条件下,用乙基纤维素作为壁材,可以得到稳定性较好的瘤胃保护葡萄糖微胶囊产品。试验三、日粮中添加瘤胃保护葡萄糖对围产后期奶牛体重、生产性能、血液生化指标和营养表观消化率的影响采用单因素随机区组试验设计,将产前21天健康和体况相近的头胎荷斯坦奶牛28头,随机分为4组,每组7头,日粮及饲养管理一致。其中,I组、II组、III组奶牛自分娩后第一天开始分别在基础饲粮中每天每头添加200 g、300 g和400 g瘤胃保护葡萄糖微胶囊,IV组为对照组,饲喂基础日粮。试验期28 d。结果表明:(1)I组、II组、III组和IV组产后体重分别减少61.99 kg、43.2 kg、42.83 kg和62.66 kg,与IV组体重减少量相比,II组、III组差异极显著(P0.01)。(2)II组、III组产奶量为26.68 kg·d-1·cow-1、26.84 kg·d-1·cow-1,极显著高于IV组24.49 kg·d-1·cow-1(P0.01),I组产奶量为25.66 kg·d-1·cow-1和IV组差异不显著(P0.05)。(3)试验组提高乳蛋白和乳糖含量,但各组差异不显著(P0.05)。(4)与对照组相比,试验组在产后7d极显著提高了血清葡萄糖浓度,降低了血清中非酯化脂肪酸和β-羟丁酸浓度,尤其III组与对照组比较,数值分别降低了18.45%和52.11%,差异极显著(P0.01)。(5)日粮中添加瘤胃保护葡萄糖微胶囊对日粮中各营养物质的表观消化率无影响。综上所述:本试验利用乙基纤维素作为壁材,通过喷雾干燥法制备出了一种新型的瘤胃保护葡萄糖微胶囊产品,过瘤胃率达到57.42%。将其添加到围产后期的奶牛日粮中,可有效减缓奶牛产后体重损失,提高产奶量,提高血清中葡萄糖浓度,降低血清中非酯化脂肪酸和β-羟丁酸浓度。建议围产后期奶牛日粮中瘤胃保护葡萄糖的适宜添加量为每天每头300g~400g。
[Abstract]:In this study, a high-rate glucose microcapsule product was developed in the rumen by a fluidized-bed coating technique, and it was added to the dairy cow's daily ration in the post-production period. The purpose of this study was to explore the effect of adding glucose to the body weight, production performance, blood biochemical index and apparent digestibility of nutrients in post-production dairy cows. The research is divided into three parts: test one, wall material and suitable concentration, select ethyl cellulose, polyacrylic resin IV and chitosan three p-H-sensitive materials as wall materials, adopt the same manufacturing process and production conditions, The best concentration of all kinds of wall materials was determined by the sensory index to evaluate the effect of coating granulation at different concentrations. The results indicated that ethyl cellulose, acrylic resin IV and chitosan can be used to protect the glucose microcapsule at the optimum concentration, the particles are more uniform, the coating is complete, and the sample drying is not easy to adhere. the preparation of the rumen-protected glucose microcapsule and the protective effect evaluation of the test 2 and the rumen protect the glucose as the core material, and the proper concentration of ethyl cellulose, polyacrylic resin IV and chitosan are used as the wall material, and the FLP-3 fluidized bed granulator is used, Three kinds of rumen protective glucose microcapsules, ethyl cellulose-M, polyacrylic resin IV-M and chitosan micro-M were prepared by spray drying. The stability of three kinds of rumen protective glucose microcapsules in the rumen was tested by in vitro and in vivo experiments. The results showed that in vitro culture, the release rate of ethyl cellulose-M microcapsules was 9. 5% ~ 15. 52% and 11. 82% ~ 35. 69%, which was significantly lower than that of polyacrylic resin IV-M microcapsule and chitosan micro-M capsule (P0.01). The degradation rate of the rumen was determined by the nylon bag method, and the degradation rate of the three products increased gradually as the time was prolonged, but the release rate of the ethyl cellulose microcapsules in the 2h-24h was still the lowest. namely, the ethyl cellulose-M microcapsule release rate polyacrylic resin IV-M microcapsule chitosan-M microcapsule (P0.01). The release rate in the rumen was 26. 68% ~ 48. 62%, and the effective protection rate was 57. 42% (k = 0.03). It can be seen that, under the condition of this test, using ethyl cellulose as the wall material, the rumen-protected glucose microcapsule product with better stability can be obtained. The effects of the addition of the rumen-protecting glucose on the body weight, the production performance, the blood biochemical index and the apparent digestibility of the dairy cows in the later stage of the experiment were designed by the single-factor random-zone group. The four groups were randomly divided into 4 groups, 7 in each group, and the daily ration and the feeding management were the same. in that group I, group II and group III, 200 g, 300 g and 400 g of the rumen-protected glucose microcapsule were respectively added to each of the first day after the first day of the delivery, and the IV group was the control group and the basal diet was fed. The results showed that (1) the post-natal weight of group I, group II, group III and group IV decreased by 61.99 kg, 43.2 kg, 42. 83 kg and 62. 66 kg, respectively, and the difference in group II and group III was very significant (P0.01). (2) The milk yield of group II and group III was 26. 68 kg 路 d-1 路 cow-1, 26. 84kg 路 d-1 路 cow-1, which was significantly higher than that of group IV. The milk yield of group I was 25.66 kg 路 d-1 路 cow-1 (P0.01). The difference between group I and group IV was not significant (P0.05). (3) The content of milk protein and lactose was increased in the test group, but the difference between the groups was not significant (P0.05). (4) Compared with the control group, the concentration of serum glucose was significantly increased in the test group at postnatal day 7d, and the concentration of non-esterified fatty acid and p-hydroxybutyric acid in serum was reduced. In particular group III and control group, the values of serum glucose decreased by 18. 45% and 52. 11%, respectively (P0.01). (5) There was no effect on the apparent digestibility of the nutrients in daily ration by adding the rumen-protective glucose microcapsule to the daily ration. To sum up, using ethyl cellulose as the wall material, a new type of rumen-protected glucose microcapsule product was prepared by spray-drying method, and the rumen rate was 57. 42%. The method can effectively slow the loss of the postpartum body weight of the milk cow, improve the milk yield, improve the glucose concentration in the serum, and reduce the concentration of the non-esterified fatty acid and the HCO3-hydroxybutyric acid in the serum. It is suggested that the appropriate amount of the rumen-protecting glucose in the dairy cows in the post-production period is 300g-400g per head per day.
【学位授予单位】：河北农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S823.5

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