Effects Of Infusion Lipopolysaccharide Into The External Pudendal Artery On Immunity And Ions’ Concentrations Of Blood In Lactating Dairy Cows

This study is composed by three defferent experiments. The fist experiment is to observe the clinlcal symptom、White blood cells and T cell subset after lipopolysaccharide (0.01μg LPS/kg BW) infusion. The second experiment is conducted to evaluate the cytokines’changing pattern after LPS infusion. The third experiment is to observe some related ions concentrations’changing pattern after LPS infusion.EXPERIMENT1:Six multiparous Holstein cows(DIM=185.67±30.11d), closed body weight (576.33±36.67kg) were choosen, and divede into two groups randomly. The6cows were administered the2treatments in a crossover design, After a1-wk preliminary period in which cows were infused only with water,3cows received the control sterile saline (0.9%NaCl,10mL) infusion and the other3cows received the LPS(Escherichia coli O111:B4,0.01μg LPS/kg BW,10mL) infusion. The infusion site is in the right external pudendal artery. Our experiment1was to observe the effect of infusion LPS onWBC and T cell subset.Results suggest that infusion with low dose(0.01μg LPS/kg BW) LPS increased the breathing rate significantly(P<0.01), and it reached the peak value after3h of infusion, the pulse rate increase significantly(P<0.01), and it reached the peak value6h of infusion, it has no significant influence on rectal temperature(P>0.05); The WBC concentration changed significantly(P<0.01), it decreased to the lowest value after6h of infusion, and increased to the peak value after48h of infusion, WBC’differential counting did not change significantly; after the LPS infusion, the CD4+T cell propotion and CD4+/CD8+ratio increased significantly(P<0.05).EXPERIMENT2:The experiment design is same with experiment1,Our experiment2was to observe the effect of infusion LPS on the concentration of TNF-α、 SAA、INF-γ in blood.Results suggest that infusion with low dose(0.01μg LPS/kg BW) LPS changed the cytokines’concentrations, the TNF-α concentration changed significantly(P<0.01), it was increasing after LPS infuison, and it reached the peak value after6h of infusion, then it decreased, after36h of infusion, it return to normal value; the SAA concentration changed significantly(P<0.01), it was increasing after LPS infuison, and it reached the peak value after48h of infusion, after about144h of infusion, it will return to normal value; the INF-γ concentration changed significantly(P<0.01), it was increasing after LPS infuison, and it reached the peak value after3h of infusion, after72h of infusion, it return to normal value。EXPERIMENT3:The experiment design is same with experiment1,Our experiment3was to observe the effect of infusion LPS on concentration of ferric ion、 calcium ion、potassium ion、sodium ion、chloride ion in blood.Results suggest that infusion with low dose(0.01μg LPS/kg BW) LPS changed the cows’concentration of some related ions, The ferric ion concentration changed significantly(P<0.05), it increased from106.170μg/mL (0h) to125.138μg/mL (6h), and it was decreasing between6and24h, increasing between24and72h, then it return to the normal value after120h infusion; calcium ion concentration increase from8.50mg/dL(0h) to8.58mg/dL(6h), it decrease after6h of infusion, and it return to the normal value after12h of infusion, it’s change was not significantly; The potassium ion increased from5.04mmol/L(0h) to4.73mmol/L(12h), it was increasing between12-24h, it was decreasing slowly between24～120h, and it’s value is lower than normal value till120h of infusion, it’s changes is significantly(P<0.05); the sodium ion increased from139.95mmol/L(0h) to142.65mmol/L(12h), and it was decreasing between12～72h, it return to the normal value after72h of infusion, and it’s changes is not significantly; chloride ion increased from104.43mmol/L(0h) to106.65mmol/L(6h), and it was decreasing between6～72h, it returned to the normal value after72h of infusion, and it’s change is not significantly.