Effects of Dietary Zinc Deficiency on Growth Performance,Small Intestinal Morphology,Barrier Function and mRNA Expression of Tight Junction Proteins in Jejunum of Broilers during 22 to 42 Days of Age
This experiment was conducted to study the effects of dietary zinc deficiency on growth perform-ance,small intestinal morphology,barrier function and mRNA expression of tight junction proteins in jejunum of broilers during 22 to 42 days of age.A total of 140 one-day-old male Arbor Acres broilers were fed the ex-perimental diet with normal addition of zinc sulfate heptahydrate(ZnSO4·7H2O)during 1 to 21 days of age;at 22 days of age,a total of 112 broilers with similar body weight were selected and randomly divided into 2 groups(7 replicates in each group and 8 broilers in each replicate)according to a completely randomized de-sign,broilers in the control group were fed the experimental diet which meet the zinc requirements of broilers(added 40 mg/kg zinc to the basal diet,and the measured zinc content was 64.36 mg/kg),and broilers in the zinc deficient group were fed the experimental diet without zinc addition(not added zinc to the basal diet,and the measured zinc content was 22.23 mg/kg).The experiment lasted for 42 days.The results showed that com-pared with the control group:1)the feed to gain ratio of broilers during 22 to 42 days of age of zinc deficient group was significantly increased(P＜0.05);2)the crypt depth in duodenum and jejunum of broilers at 42 days of age of zinc deficient group was significantly increased(P＜0.05),and the villus height/crypt depth ra-tio in duodenum,jejunum and ileum and villus height and villus surface area in jejunum of broilers at 42 days of age were significantly decreased(P＜0.05);3)the diamine oxidase activity and fluorescein isothiocyanate-dextran content in wing vein and hepatic portal vein serum of broilers at 42 days of age of zinc deficient group were significantly increased(P＜0.05);4)the mRNA expression levels of Claudin-1 in jejunum of broilers at 42 days of age of zinc deficient group was significantly decreased(P＜0.05).In conclusion,dietary zinc defi-ciency can impair the intestinal mucosal integrity and barrier function of broilers possibly by decreasing the mR-NA expression of Claudin-1,and thus decrease the feed conversion efficiency of broilers.[Chinese Journal of Animal Nutrition,2024,36(1):235-244]
zinc deficiencybroilersgrowth performanceintestinal barrier functiontight junction protein
万方数据
维普
