Evaluation On The Effectiveness And Tolerance Of Organic Iron In Weaned Piglets

In this study,the effectiveness and tolerance of a new amino acid complex iron in weaned piglets were explored in order to providing the basis for the development of efficient and safe iron sources.I.Effective experiment288 weaned piglets were selected as experimental animals,and 6 treatments were designed,with 8 replicates for each treatment and 6 piglets for each replicate.The six treated diets were based diets supplemented with 0(negative control group),30(test group I),60(test group II),90(test group III)and 120(test group IV)mg Fe/kg of new iron source,and 90 mg Fe/kg ferrous sulfate(positive control group)respectively.The production performance and blood biochemical indexes of all piglets on 14 th or 42 nd days of feeding were detected and analyzed,and the organ indexes,intestinal structure and iron metabolism indexes of group III and the two groups of controls(negative and positive control groups)were tested.The test results are as follows:(1)Growth performance.In test group II,the average daily gain of 0-14 and 15-42 days,and the whole period was the highest,and the ratio of feed to gain was the lowest,but the difference was not significant(P>0.05).(2)Fur quality score.The fur quality scores of test group III and test group IV were significantly higher than those of the negative control(P<0.05).(3)Blood index.On the 14 th day of the test,the red blood cell counts of test group III and test group IV were significantly higher than those of the negative control group(P<0.05).In addition,the red blood cell counts of test group III was also significantly higher than that of the positive control group(P<0.05).On the 42 nd day,the hematocrit of test group II,test group III,test group IV and positive control group were significantly higher than that of negative control group(p < 0.05).The hemoglobin of test group III,test group IV and positive control group was significantly higher than that of negative control group(p < 0.05).The average hemoglobin content of test group IV and positive control group was significantly higher than that of negative control group(p < 0.05).The average erythrocyte volume of positive control group was significantly higher than that of negative control group(p < 0.05).The red blood cell count on the 14 th day,hematocrit,hemoglobin and average hemoglobin content on the 42 nd day of piglets were linearly correlated with the additional dose of iron addition in the test groups(P<0.05).On the 14 th day of the test,serum iron of test group IV was significantly higher than that of negative control group(P<0.05).Moreover,there was no significant difference in other serum indexes(p>0.05).(4)Organ index.There was no significant difference in heart,liver,spleen,kidney and other organ indexes among groups(P>0.05).The jejunal crypt of the positive control group was significantly deeper than that of the negative control group(P< 0.05).The content of renal iron in test group III and positive control group was significantly higher than that in negative control group(P< 0.05).The liver iron content of group ? was significantly higher than that of negative control group(P< 0.05).There was no significant difference in piglet spleen iron content among the groups(p>0.05).Fecal iron content was linearly related to iron addition in the test groups(P< 0.05).(5)Iron metabolism index.There was no significant difference in the expression level of liver iron metabolism related genes,and the content of intestinal iron absorption and transport related proteins among groups(P>0.05).II.Tolerance experiment144 weaned piglets were selected as experimental animals,and 3 treatments were designed,with 8 replicates for each treatment and 6 piglets for each replicate.The three treated diets were supplemented with 0(control group),90(effective dose group)and 900(high dose group)mg Fe/kg new iron sources respectively.The production performance,blood biochemical indexes,organ indexes,intestinal structure and iron metabolism indexes of piglets in each group after 14 or 42 days of feeding were detected and analyzed,and histopathological examination was carried out.The test results are as follows:(1)Production performance.There was no significant difference in the production performance and mortality of piglets in each stage(P>0.05).Compared with the control group,the high-dose and effective-dose groups significantly improved piglet skin redness and reduced diarrhea rate(P<0.05),while only effective-dose group significantly improved coat score(P<0.05).(2)Blood index.Compared with the control group,the high-dose group significantly increased the white blood cell count,red blood cell count,hematocrit and hemoglobin on the 14 th day of the test(P<0.05).In addition,the hemoglobin was significantly higher than that of the effective-dose group(p < 0.05).Furthermore,the high-dose group significantly increased hemoglobin,hematocrit,mean red blood cell volume and mean hemoglobin content than those of the control group on the 42 nd day(P<0.05).The mean red blood cell volume and mean hemoglobin content were significantly higher than those of the effective-dose group(P<0.05).There was no significant difference in serum indexes among the groups(P>0.05).(3)Organ index.There were no significant differences in organ indexes of liver,heart,spleen,lung and kidney,villus height,crypt depth and villus-to-crypt ratios among different groups(P>0.05).The iron content of kidney,liver and spleen of high-dose group was significantly higher than that of the control group(P<0.05),while the iron content of liver,spleen and feces was significantly higher than that of control group and effective-dose group(p<0.05)(4)Iron metabolism index.There was no significant difference in mRNA level of liver iron metabolism related genes,intestinal iron absorption and transportation related protein content among groups(P>0.05).No pathological changes were found in heart,liver,spleen,lung,kidney,pancreas,lymph nodes,stomach,bone marrow,duodenum,jejunum,ileum,rectum and other tissues in the high-dose group.III.ConclusionsSupplementing new iron sources has a tendency to improve the production performance of weaned piglets,significantly improve many iron sensitive indexes of piglets,and is significantly better than ferrous sulfate in improving red blood cell count.New iron sources has no significant effect on intestinal structure and it is an effective iron source for weaned piglets.The addition of 900 mg Fe/kg can further improve hemoglobin,iron content in organs and other indicators,and has no significant negative impact on the performance of piglets.