Effect Of Gossypol In Diet On Water And Ion Metabolism Of Sheep

The present experiment was designed to feed 5 Kazak male sheep with gossypol of 0,984,1353 and 1722mg/d respectively during the four periods,each period last 18d, total 72d. The trial period for each sheep were collected fresh faecal samples,urine samples and determine water intake,feed intake, pH of urine and the content of water in faecal,Study on the effect of gossypol on sheep drinking, urination volumes, pH of urine and related indices(TrialⅠ).Take blood from jugular vein of sheep in Trials,preparation of serum,and urine was collected,determine the levels of related hormones in serum and the contents of ion in serum and urine,analysis the causes of gossypol effects on water metabolism in sheep(TrialⅡ).Test with 1% ferrous sulfate,1% sodium hydroxide solution and distilled water gossypol,and dried at 60℃for 48h,the use of aniline determination of free gossypol content of different processing methods and processing time on the effect of free gossypol(TrialⅢ).The results shows that the water consumption,urine output,wheat straw feed intake,faecal output, pH of urine and the moisture content of faecal of sheep without significant change(p>0.05) as the amount of gossypol increasing during the four periods(TrialⅠ).The levels of antidiuretic hormone,rennin and cortisone didn't change significantly;the level of adreno cortieotropic hormone and aldosterone were both decline at the previous three periods,but increased during the fourth period compare with the third period(p<0.05);The level of Cl-and Ca2+in serum decreased,and the level of Cl- in the third period is extremely significant lower than the first period(p<0.01).As for the Ca2+,the three period is significant lower than the first period(p<0.05),but the contents comeback to the first level in forth periods;the level of K+,Inorg-P,Mg2+ in serum didn't change significantly(p>0.05);The content of Na+and Inorg-P didn't change significantly(p>0.05);The content of Cl-was increased at the previous three periods,the third period is significant higher than the first period,but the content of Cl-in fourth period return to the level of the first period;while the content of K+,Mg+,Ca2+of the fourth period were lower than the previous three periods(p<0.05)(TrialⅡ).With the time,the content of free gossypol was not change significant by1% ferrous sulfate,1%sodium hydroxide and distilled water,we can see three methods of free gossypol treatment is independent of time,and may have related on sample pretreatment(TrialⅢ).The result can be drawn that gossypol on water intake and discharge of sheep had no obvious effect because of it had no effect on the level of antidiuretic hormone,rennin and cortisone, adreno cortieotropic hormone and aldosterone.Although free gossypol causesNa+,Cl-,Ca2+ concentration fluctuation in serum, theNa+,Cl-,Mg2+,Ca2+ concentration fluctuation in urine,but still did not cause water intake and urine output changes of sheep,then that sheep feeding cottonseed hull and other cotton by-products caused by decreased urine output,is not caused by gossypol.Adsorbed the samples of high content of water with filter paper,dried at 60℃for 48h,determination FG concentration,but the values were not accurate,so this method is not feasible.