Effects Of Adsorbent And Aflatoxin B₁ On Growth Performance,Intestinal And Immune Function Of White Feather Broilers

The effects of smectite clay on growth performance and immunological function in broilers fed with aflatoxin B₁?AFB₁?-contaminated feed were investigated.A total of 576 one-day-old AA male broilers were randomly distributed to 6 treatments with 8 replicates and 12 broilers per replicate.The birds were fed diets containing 0,60 or 120 ppb of AFB₁ and 0 or 2.5 kg smectites clay per tonne as a 3 × 2 factorial study design.The experiment lasted for 42 days with two feeding phases?1²1 d and 22⁴2 d?.On d 7 and 14,all broilers were vaccinated against Newcastle disease vaccine.On d 14 and 28 one bird was randomly chosen from every replicate for serum sample analysis,and the Newcastle Disease Antibody titer were determined.At the end of each phase,one bird was randomly chosen from every replicate for sample analysis.The growth performance,organ index,serum indicators,intestinal morphology,s Ig A of jejunal mucosa,liver and spleen sample were determined.The results as followed:1)AFB₁ – treated diets significantly decreased feed intake at the early phase?P < 0.05?,but did not significantly affect the other performance?P > 0.05?,and significantly increased the serum ALP activity at 21 days?P < 0.05?,and had a tended to decreased UA of broilers on d 21?0.05 < P < 0.10?.Adsorbent addition tended to increased average daily gain in the last phase and the thymus index on d 42 of broilers?0.05 < P < 0.10?.The serum T-Bil concentration on d 21 and the serum ALT activity on d 42 were significantly reduced in broilers fed with adsorbent?P < 0.05?.The interaction between AFB₁ and adsorbent on growth performance,immune organ index and serum biochemical index of broilers did not reach a significant level?P > 0.05?.2)In the AFB₁ treatment group,the VH/CD values in ileal was significantly increased,the CD in ileum and s Ig A concentrations in jejunum mucosa were significantly decreased on d 21?P<0.05?.There had a increasing tendcy observed for the expression of occluding m RNA on d 21 and the expression of ZO-1 m RNA in jejunum on d 42,and had a decreasing tendcy observed for the VH/CD in jejunum on d 42 of broilers?0.05 < P < 0.10?.Compared with no-added group,the CD of duodenum,VH and CD of jejunum of broilers of adsorbent-added groups were significantly increased on d 21,and the VH,CD,VH / CD of duodenum,s Ig A concentration and the expression of Bax and ZO-1 m RNA of jejunal mucosa were significantly increased and the expression of Bcl-2,claudin-1 m RNA and Bcl-2/Bax value of jejunal mucosa were significantly decreased of broilers of adsorbent-added groups on d 42?P < 0.05?.There had a increasing tendcy observed for the Bcl-2/Bax value in jejunal of broilers of adsorbent-added groups on d 21?0.05 < P < 0.10?.The interaction of AFB₁ and adsorbent on ileal VH,VH / CD value on d 21 and the exression of ZO-1 m RNA of jejunal on d 42 reached a significant level?P < 0.05?.There was a tendency of interaction of AFB₁ and adsorbent on s Ig A of jejunal mucosa on d 21 and CD of ileal on d 42?0.05 < P < 0.10?.3)The levels of Ig A and Ig M in serum,T-AOC and the expression of IL-1? m RNA in liver,and the expression of IFN-?,TGF-?1 and TLR-4 m RNA in spleen of AFB₁-treated groups were significantly increased of broilers on d 21;the level of serum Ig G and the expression of the IL-6 m RNA in liver of broilers were significantly increased?P < 0.05?.There had a increasing tendcy observed for the exression of liver TGF-?1and spleen IL-1? m RNA on d 21 and the levels of a1-AGP in jejunal of broilers of adsorbent-added groups on d 42?0.05 < P < 0.10?.The liver is damaged by AFB₁ and inflammatory cell leaching and cavitation phenomenon.After adding the adsorbent,the levels of Ig A and SAA in serum,the expression of IFN-?,IL-1? m RNA in liver and the expression of IFN-?,TLR-4,TNF-? and IL-1? m RNA in spleen on d 21 of broilers were significantly decreased,the Ig M in serum and liver T-AOC was significantly increased?P <0.05?.The level of serum Ig A and Ig M and the expression of IL-6 and TNF-? m RNA in the liver were significantly decreased on d 42?P <0.05?.There had a increasing tendcy observed for the liver T-AOC and the expression of TGF-?1 m RNA of broilers by supplementation of adsorbent on d 21?0.05 < P < 0.10?.Damage to the liver by AFB₁ can be ameliorated by adsorbents and reduce the leaching of inflammatory cells and cavitation phenomenon.The interaction of AFB₁ and adsorbent was observed for the levels of Ig A in serum,the expression of IFN-? m RNA in liver on d 21 and 42,the Ig M in serum and T-AOC in liver and the expression of IFN-? m RNA in spleen on d 21?P <0.05?.The interaction trends of AFB₁ and adsorbent was observed for the liver T-SOD and the expression of spleen IL-6 m RNA on d 21 and the levels of Ig G,SAA and a1-AGP in serum on d 42 of broilers?0.05 < P < 0.10?.In conclusion,60,120 ppb AFB₁-treated diets have adverse effects on growth performance of broilers,while injury to intestinal health and immune function of broilers.Supplementation of adsorbent to the diet can alleviate the negative effects induced by AFB₁.