J.J.  Zuo, A.H.  Guo, X.Y.  Yan, M.  Xu, W.G.  Xia, D.Y.  Feng, 
    Supplementation of β-Mannanase in Diet with Energy Adjustmenton Affect Performance, Intestinal Morphology and Tight Junction Proteins mRNA Expression in Broiler Chickens,
    Journal of Animal and Veterinary Advances,
    Volume 13,Issue 3,
    2014,
    Pages 144-151,
    ISSN 1680-5593,
    javaa.2014.144.151,
    (https://makhillpublications.co/view-article.php?doi=javaa.2014.144.151)
    Abstract: The objective of this study was to assess the effects of commercial 
  β-mannanase enzyme supplementation in low-energy corn-soybean meal diets 
  on performance, intestinal morphology and mRNA expression of intestinal tight 
  junction proteins in 1-21 days broiler chickens. The 1800, 1 day old broiler 
  chicks were divided into 5 treatment groups, 6 pens in each treatment. The study 
  was performed in a randomised complete block design. The 5 treatments were Positive 
  diet Group (PG) with basal energy level, Negative diet Group (NG) with lower 
  energy of 502.08 kJ kg<SUP>-1</SUP> and other groups supplemented with 150, 
  300 and 450 mg kg<SUP>-1</SUP> &#946;-mannanase based on NG. Decrease of energy 
  in NG resulted in loss of the Average Daily Gain (ADG) (p&lt;0.05) and Feed 
  Conversion Ratio (FCR) (p&lt;0.05). Based on the NG, supplementation with &#946;-mannanase 
  in diet significantly improved the Average Daily Gain (ADG) (p&lt;0.05) and 
  Feed Conversion Ratio (FCR) (p&lt;0.05) of birds. ADG of groups with enzyme 
  and lower energy reached to the level of PG. Supplementation with 300 g ton<SUP>-1</SUP> 
  &#946;-mannanase increased the villus height of the small intestine (p&lt;0.05) 
  and 450 g ton<SUP>-1</SUP> &#946;-mannanase significantly decreased the crypt 
  depth (p&lt;0.01). The addition of &#946;-mannanase at 150, 300 and 450 g ton<SUP>-1</SUP> 
  to the diets increased the ratio of crypt depth to villus height of the duodenum 
  and jejunum in birds (p&lt;0.01). The ratio of crypt depth to villus height 
  of the ileum was also increased with 300 and 450 g ton<SUP>-1</SUP> &#946;-mannanase 
  supplementation compared to the low-energy diet group (p&lt;0.01). Chicks fed 
  diet with the &#946;-mannanase showed an increased mRNA expression of ZO-1 in 
  the duodenum compared with the low energy diet (p&lt;0.05). Supplementation 
  with 300 and 450 g ton<SUP>-1</SUP> &#946;-mannanase to the diets enhanced the 
  mRNA expression of Occludin and ZO-1 in the jejunum (p&lt;0.05) and 300 g ton<SUP>-1</SUP> 
  &#946;-mannanase increased enhanced the mRNA expression of Occludin and ZO-1 
  in the ileum (p&lt;0.05). Thus, the addition of &#946;-mannanase to low energy 
  diets improved the performance, gut morphology and mRNA expression of intestinal 
  tight junction proteins.
    Keywords: B-mannanase;performance;intestinal morphology;intestinal tight junction protein;broiler