Study Of β-carotene Digestion And Uptake In Rumen And Intestinal Of Goats And Its Anti-oxidative Effect

In this paper, in vitro fermentation, catheters of blood vessel and everted gut sac technology were used to estimate the effect ofβ-carotene on ruminal fermentation, the stability ofβ-carotene in rumen and its uptake and conversion in the small intestinal, and the effect ofβ-carotene on anti-oxidative indices of serum were also studied. The results showed that:1. Different levels ofβ-carotene (10, 50, 100, 200, 500mg/L) were added as five treatment groups to find whether it affected the rumen fermentation in vitro and a blank was used as control. The results showed that: NH₃-N concentration of 50,100,200mg/L group were significantly lower than the blank(P<0.01); MCP concentration in allβ-carotene added groups were higher than the blank, and 200,500mg/L group were significantly higher(P<0.01); TVFA seemed not affected byβ-carotene (P>0.05). The conclusion is thatβ-carotene enhanced the use of NH₃-N and stimulated the growth of ruminal microorganism.2. Three ruminally fistulated Xu-huai white goats were used as donors of rumen fluid, substrates of different roughage to concentrate ratio (contain 50%, 80%, 100% roughage respectively) were incubated with buffered ruminal fluid in vitro for 24hs.β-carotene (10mg/L) was added to find its stability in the rumen fermentation in vitro. The results showed that: The roughage to concentrate ratio didn't affect the stability ofβ-carotene in rumen fermentation in vitro and in the condition of this experiment, the disappearance ratio ofβ-carotene between 3-24h incubation was about 6%-20%.3. Superior vena cava and carotid artery catheters were used to study the uptake and conversion of two different level ofβ-carotene(27.5 and 55mg/d) in the small intestinal in vivo. The results showed that: The concentration ofβ-carotene in the serum of goats were not detected in both 27.5mg/d and 55mg/d groups in this experiment; The concentration of vitamin A in the serum of goats were improved in both groups after feeding. The maximum vitamin A level of 55mg/d group was about 1.5 times than the 27.5mg/d group after the first day feeding; The vitamin A level of 27.5mg/d and 55mg/d groups reached 0.547 and 1.396ug/ml respectively after feeding for 1 week, and didn't reached steady-state in the experimental period.4. The everted gut sac method was used to estimate the uptake and conversion ability ofβ-carotene in different site of small intestinal(duodenum, forepart, middle part and behind part of jejunum, ileum). The results showed that: The conversion ability of small intestinal was duodenum> behind part of jejunum> forepart of jejunum> middle part of jejunum> ileum; The main uptake site of small intestinal of Xu-huai white goat was the forepart of jejunum.5. Four Xu-huai white goats were used as experiment animals, a 4×4 Latin Square experiment was carried out to study the effects of four doseβ-carotene on anti-oxidative indices and Maleic Dialdehyde in serum. The results showed that: T-AOC of group D was significantly higher than group A,B and C (P<0.01), group C was higher than group B(P<0.05) and significantly higher than group A,B and C (P<0.01), group A and B showed no significant (P>0.05). GSH-Px of group C and D was significantly higher than group A and B (P<0.01), while group A and B showed no significance; The activity of CAT in group D was much higher than that in group A and B (P<0.01), and there was significant difference between group C and D (P<0.05); the activity of SOD had great difference among group A, C and D (P<0.01), compared with group B, group C was higher (P<0.05), and group D was the highest (P<0.01); The content of MDA decreased with the increase ofβ-carotene.