Study Of The Effects Of Different Iron Sources And Levels On Iron Nutrition Of Weaned Piglets

The experiment mainly studyed the effects of iron glycine chelate (Fe-Gly) and ferrous sulphate monohydrate (FeSO4·H2O) in combination on growth performance, blood physiological biochemical indices, the apparent digestibility of trace element, iron absorption transport related gene expression in weaned piglets in order to determine the optimal combination model of organic and inorganic iron and then provide iron preparations' scientific applications with theory basis.A total of two hundred and forty weaned piglets (Duroc X Landrace X Largewhite,35 day-old) with an average of (9.04±0.40) kg were randomly allotted to six groups with 4 replicates in each group and 10 piglets per replicate. Treatments:I) Positive control (basal diet+80 mg Fe/kg diet from FeSO4-H2O), ?) 60 mg Fe/kg diet from FeSO4·H2O+12 mg Fe/kg diet from Fe-Gly, ?) 40 mg Fe/kg diet from FeSO4·H2O+24 mg Fe/kg diet from Fe-Gly, ?) 20 mg Fe/kg diet from FeSO4·H2O+36 mg Fe/kg diet from Fe-Gly, V) 48 mg Fe/kg diet from Fe-Gly, ?) Negative control (basal diet only, no Fe supplementation). Trial test period was 7 days, test period was 28 days.The results showed that:1) Compared with negative control group, adding iron source could significantly improve average daily gain (ADG), red blood cell (RBC), hemoglobin (HGB), hematocrit (HCT), alkaline phosphatase (ALP), succinate dehydrogenase (SDH), ferritin (Fn), blood urea nitrogen (BUN), serum sugar (GLU), total protein (TP), albumin (ALB), immunoglobulin G (IgG), serum iron, transferrin saturation (TSAT), the iron content of liver, heart, kidneys, spleen, muscle and waste, iron apparent digestibility, liver and duodenum and jejunum hepcidin mRNA expression and duodenum PepTl mRNA expression (P<0.05); adding iron source could significantly reduce feed/gain ratio (F/G), serum total iron binding force (TIBC), transferrin (Tf), liver TF mRNA expression and duodenum and jejunum DMT1 mRNA expression of weaned piglets (P< 0.05), the iron nutrition level of weaned piglets was improved significantly.2) Compared with the positive control group, the dietary with Fe-Gly and FeSO4·H2O in combination could significantly increase TSAT, liver iron content, iron and zinc apparent digestibility, liver hepcidin mRNA expression and duodenum and jejunum PepTl mRNA expression (P< 0.05) as well as could significantly decrease iron, zinc content of waste in weaned piglets (P< 0.05). What's more, weaned piglets whose diets supplemented with 36 mg/kg Fe-Gly and 20 mg/kg FeSO4·H2O in combination behaved best.3) With the added level of Fe-Gly increasing, ADG, RBC, HGB, HCT, ALP, Fn, BUN, GLU, TP, SI, TSAT, the iron content of liver, kidneys, spleen and muscle, iron apparent digestibility, liver and duodenum and jejunum hepcidin mRNA expression, duodenum and jejunum PepTl mRNA expression of weaned piglets increased linearly or quadratically (P< 0.05); and meanwhile F/G, TIBC, liver TF mRNA expression and duodenum and jejunum DMT1 mRNA expression of weaned piglets decreased linearly or quadratically (P< 0.05).In conclusion, there were significant effects of adding iron preparation on weaned piglets'iron nutrition levels compared with no iron source supplementation. What's more, organic iron and inorganic iron in combination not only had better effect on iron supplemented than used inorganic iron singly and could reduce significantly the feces's trace element excretion in weaned piglets'diets. Taking all the indicators into consideration, weaned piglets whose diets supplemented with 36 mg/kg Fe-Gly and 20 mg/kg FeSO4-H2O in combination achieve the best results.