Effects And Mechanisms Of Ultrafine Powder Of Senecio Scandenson Growth Performance In Piglet

In the present paper, Senecio scandens Buch.-Ham was selected to investigate the effects of ultrafine pulverization on size distribution and morphological characterization and to determine the content of total flavonoids of ultrafine powder of S. scandens as well as to study the effects of the ultrafine powder of S. scandens on growth performance in piglets. The ultrafine powder of S. scandens at different doses was added into the feed.Ninety pigs(Duroc × Landrace × Yorkshire) were selected with an initial body weight about 10 kg according to the randomized block design and the principle of male and female in half. The piglets were divided into 5 groups, each group contained 3 pens and each pen contained 6 piglets. The piglets in groupⅠ were fed with basic diet. 75 mg/kg chlortetracycline and 20 mg/kg colistin sulfate were added in basic diet for group Ⅱ, and 0.4%, 0.8%, 1.2% of ultrafine powder of S. scandens were supplemented in basic diet for group Ⅲ, group Ⅳ and group Ⅴ, respectively. The piglets were raised for 30 days to study the effects of the ultrafine powder of S. scandens on growth performance, diarrhea incidence, serum biochemical indices, fecal microorganism, digestibility of nutrients and the expression of IGF-I mRNA. The results were as follows:1. The volume median diameter(d0.5) value of the ultrafine powders were 8.88 μm, while the diameters of 90% of the ultrafine powder were equal or lesser than 23.37 μm, which showed the diameter accorded with the requirement of the ultrafine pulverization. The images of scanning electron microscopy showed that the ultrafine powder has no unbroken structures, and the ultrafine powder was narrower and more uniform size than the ordinary powder.2. After validation, the relative deviation was small and the method was suited to detect the total flavonids of the ultrafine powder of S. scandens. The standard curve of hyperoside was y=0.0534x-0.051, and the linear correlation of hyperoside was good in the range of 3.2~16 μg/m L(R2=0.9975). The total flavonoids of ultrafine powder of S. scandens were 2.72%.3. Adding ultrafine powder of S. scandens into the feed of piglets increased the average daily gain and the average daily feed intake, while the ratio of feed and meat was reduced, among which the addition of 0.8% of the ultrafine powder significantly increased the average daily gain and decreased the ratio of feed and meat, without difference between group Ⅱ and group Ⅳ. Adding the ultrafine powder of S. scandens reduced the diarrhea incidence in all groups of piglets. And adding 0.8%, 1.2%, like adding antibiotics, significantly reduced the diarrhea incidence. Adding the ultrafine powder of S. scandens improved the levels of serum GLU, TG, T3, T4, IGF-I and reduced the level of serum BUN, among which adding 0.8% of the ultrafine powder significantly increased the levels of serum T3 and IGF-I, and significantly reduced the concentration of serum BUN.4. A significant reduction in the number of Escherichia coli was observed when the antibiotics were added in the feed. Adding the ultrafine powder reduced the number of E. coliin different extents, i.e., at day 30 of the experimentation, the significant reduction of E. coli was observed in the groups with 0.8%, 1.2% of the ultrafine powder addition, respectively. The number of lactic acid bacteria in the test groups was higher than that in the blank control group but no significantly different was observed. Adding the ultrafine powder improved the apparent digestibility of nutrients in different extents, among which the apparent digestibility of nutrients in the group added 0.8% of the ultrafine powder was the best.5. With the increase of addition of theultrafine powder, the relative expression of IGF-I mRNA in blood of the piglets showed an increasing trend. In comparison with the blank control group, the relative expression of IGF-I mRNA in blood of the group Ⅲ, Ⅳ, Ⅴwere increased by 11.07%, 16.61%, 39.85%. The relative expression of the group Ⅲ, Ⅳ, Ⅴ were higher than that in group Ⅱ. No significant reduction was observed among the five groups.In conclusion, adding the ultrafine powder of S. scandens in dietary of piglet decreased the diarrhea incidence, regulated the structure of intestinal microflora, improved the intestinal environment, increased the digestion and absorption abilities of the piglets, regulated the expression of IGF-I mRNA, perfected the blood biochemistry targets, and improved the growth performance of the piglet, in which the addition of 0.8% of the ultrafine powder was the best. The possible mechanisms of the ultrafine powder ofS. scandensimproving growth performance of the piglets could be: the medical components of S. scandens(such as flavonoids) inhibited proliferation of the harmful bacteria, improved the growth of beneficial bacteria in the gut and the intestinal microbes environment, and reduced the diarrhea incidence as well as made the digestibility of nutrients in piglets improved. Meanwhile, the S. scandens played the role of nutrition, which could regulate the expression of IGF-I mRNA and the secretion of T3, T4, IGF-I, and then affect the metabolism of carbohydrates, fats and proteins. So the ultrafine powder of S. scandens played a dual role of pharmacological efficacy and nutrition, promoting the improvement of the growth performance of piglets.