Effects Of Noni Fruit Polysaccharide On Rumen Fermentation,Nutrient Digestion,Immunity And Antioxidation In Cashmere Goats

Noni fruit has a wide range of sources and has a high nutritional value.Noni and its polysaccharides both have biological activities such as antibacterial and antitumor.In this paper,the in vitro batch culture method was used to select the appropriate dosage of noni(Morinda citrigolia L.)fruit raw powder(NFD)and its polysaccharide(NFP)in the diet of cashmere goats in vivo,and the animal experiment was conducted to explore the effects of NFP on rumen fermentation,nutrient digestion,immunity and antioxidation of cashmere goats.The results of the study are of great significance for rational use of Noni resources and the development of a new green feed additive market that can replace antibiotics.This paper mainly includes three experiments.In the first experiment,the in vitro batch culture method combined with multiple forages associative effect indicator(MFAEI)was used to select the appropriate dose of NFD or NFP in the diet of cashmere goats by detecting the relevant indicators of rumen fermentation at each culture time.The NFP was obtained from water extraction and alcohol precipitation.The extraction rate was 11.02%,and polysaccharide content was 64.91%.The single-factor completely randomized trial design was used.The test consisted of 9 treatment groups with 6 replicates per treatment.Among the treatments,the fermentation substrate of the control group contained neither NFD nor NFP(CON,0 dose group).The other 8 groups were the experimental groups.And 4 of them were NFD groups in which corn were replaced with 1.00%(D1 group),2.00%(D2 group),3.50%(D3 group)and 5.00%(D4 group)NFD on the basis of dry matter in the fermentation substrate,respectively.The rest were NFP groups which were added 0.10%(P1 group),0.20%(P2 group),0.40%(P3 group),and 0.55%(P4 group)NFP to their fermentation substrate.The polysaccharide doses in the P1 to P4 group were equal to those in the D1 to D4 group.Samples of each group were collected at 3h.6h,9h,12h and 24h.The results showed that different doses of NFD or NFP in vitro could significantly reduce the number of protozoa,the ammonia nitrogen(NH3-N)concentration and the pH value,and could significantly increase the concentration of bacterial protein(BCP),volatile fatty acids(VFA),and gas production(P<0.05).Combined with the results of MFAEI,the promotion on rumen fermentation was better when the doses of NFD and NFP were 3.50%and 0.40%respectively.And the promotion from NFP was better than NFD.The second and the third experiments were carried out on the basis of the appropriate dose of NFP screened in vitro.Cross-test design was used.Twelve healthy wethers with a similar body weight(44.72±3.54kg)and age of 2.5 years were selected as test animals.They were randomly divided into two groups,each group of 6 goats.The CON group was fed the basal diet,and the NFP group was fed with the diet which was supplemented with 0.40%NFP in the basal diet.The test was conducted in two phases with 28d per phase.In every phase,the trial period is 21 days and the transition period is 7 days.Samples were taken for measurement at the last week of the trial period.In the second phase,the test animals in the CON group were interchanged with the NFP group,and the treatment method was the same as the first phase.The second experiment mainly studied the effects of adding 0.40%NFP in the diet on the rumen fermentation and nutrient digestion of cashmere goats.The results showed that the addition of 0.40%NFP in the diet could significantly reduce the number of protozoa,the NH3-N concentration and significantly increase the concentration of BCP and VFA(P<0.05),and had no significant effect on pH(P>0.10).And NFP could also obviously increase the apparent digestibility of dry matter,crude protein,neutral detergent fiber,acid detergent fiber,calcium and phosphorus(P<0.05),and tended to significantly increase the apparent digestibility of ethanol extract(P<0.10).Moreover,in this dosage,the average daily feed intake,total weight gain and average daily gain of cashmere goats(P<0.05)were significantly increased,while the feed efficiency had no striking change(P>0.10).The third experiment mainly studied the effects of adding 0.40%NFP on the immune responses and antioxidant functions of cashmere goats.The results showed that the addition of 0.40%NFP in the diet significantly increased the concentrations of interleukin-6,tumor necrosis factor-a,nitric oxide(NO)and inducible NO synthase in serum(P<0.05),while had no prominent effect on interleukin-1?(P>0.10).And the activity of catalase,glutathione peroxidase,total superoxide dismutase and thioredoxin reductase in serum was significantly increased(P<0.05)with this doseage.The concentrations of malondialdehyde and reactive oxygen species(ROS)were significantly or tended to be significantly reduced,respectively(P<0.05,P<0.10).And the total antioxidant capacity had no distinct change under this condition(P>0.10).Combining various rumen fermentation indicators and MFAEI,we can draw that the addition of noni fruit and its polysaccharide to the in vitro rumen fermentation substrate of cashmere goats can promote the rumen fermentation,and the promotion were more effective when the individual additive amounts of NFD and NFP were 3.50%and 0.40%respectively.Animal experiments showed that adding 0.40%NFP to the diet could improve the rumen fermentation function and the apparent digestibility of various nutrients in cashmere goats.Meanwhile,this addition could enhance the immune regulation function and antioxidant function.