| Soil ingestion herbivor was very common in grazing system of the Qinghai-Tibet Plateau,and was also an important way to obtain mineral elements,meanwhile could affect mineral nutrition level,change rumen inner environment and.However,soil ingestion was affected by many factors from season,grassland vegetation,et al.The present study was carried out to research the effect of soil ingestion on intake,nutrition digestion,rumen fermentation,bacterial diversity,mineral nutrition,and productivity of Tibetan sheep.Thirty sheep with five-month age and similar bodyweight(18 Kg)were selected and divided into five groups randomly,and feeded soil with none,5%,10%,15%,and 20%proportion in its dairy for every group.These sheep raised in metabolism cages in the whole trial period with 30 days,and was feed twice a day with oat grass,free intake and drink.Nutrition digestion,rumen fermentation,and bacterial diversity for Tibetan sheep with different soil supplementation were researched conparedly,and the potential effect of soil ingestion on nutrition digestion was discussed furtherly,including the microbiological process.The main results of this research as follows:The effects of soil ingestion on the nutrient digestion and ruminal fermentation parameters of Tibetan sheep:the results were showed that NDSD and ADFD decreased greatly with soil content increase in diets,and although there were no significant group difference for DMD,EED and CPD,10%group was better relatively including daily intake and daily body weight gain.Rumen fermentation characters were showed that there was no greaterly group variation in rumen pH and NH3-N,but significant group difference in acetic acid,propionic acid,isovaleric acid and TVFA(P<0.05),and espical in 5%group.The influence of soil ingestion on serum mineral elements in Tibetan sheep:With the increase of soil in dairy,the serum elements K,Na,Ca and P showed significant changes(P<0.05),but there was no significant difference among Mg,Cl,Cu,Fe,Mn,Zn and Se(P>0.05).However,serum elements K,Na and Ca increased firstly and then decreased.The levels of plasma K,Na and Ca of Tibetan sheep with 5.26 mmol/L,].36 mmol/L,and 1.27 mmol/L,individualy in 5%group were higher than other;but serum element P gradually decreased,and the serum K,Mg,P,Cu,Fe,Mn,Zn,and Se were all higher than the critical value,while Na and Ca were lower than the critical value.Effects of soil ingestion on rumen microbial diversity of Tibetan Sheep:it was found that the dominant bacteria of rumen bacteria in Tibetan sheep were Firmicutes,Bacteroidetes and Fibrobactere with 16 SrRNA high-throughput sequencing technique,and the proportion of Firmicutes was the highest,and phylums was the most dominant and accounting for 53.56%in group 10%.Corelationship analysis was showed that there was significantly positively relation between NDFD,pH values and rumen bacteria of the Firmicutes(P<0.05),,and was a significantly positively relation between NH3-N,VFA and Fibrobacteres(P<0.05).The PICRUSt function predicts that the most important functional gene family of the Tibetan sheep is membrane transport,and the membrane transport function is the strongest in 10%group,and this is may be the reason that the strongest nutrient digestion of DMD,CPD,EED and NDSD occurred in this group.This experiment was first conducted to study the nutrient digestion,serum mineral elements,ruminal fermentation parameters,and rumen bacterial diversity of Tibetan sheep systemically.meanwhile,PICRUSt was used to fully predict the function of bacterial genes,and provided a comprehensive theoretical basis for the mineral nutrient supplement of grazing livestock on the Qinghai-Tibet Plateau,and also provided scientific guidance for livestock grazing management. |
PDF Full Text Request