THE EFFECT OF XYLANASE, RONOZYME WX, ON TILIPIA GROWTH WITH HIGH AND LOW FISH MEAL DIETS

Aquaculture plays a critical role in global food security, and optimizing nutrition is essential for enhancing fish health and growth performance. Arabinoxylans and xylans constitute the primary NSP fraction of cereals and their by-products. The used enzyme, an endo-1,4-β-xylanase (single enzyme product) degrades both the soluble arabinoxylans responsible for an increased viscosity, and the insoluble arabinoxylans, major cell wall constituents which entrap the proteins. Conclusions & Benefits: When adding the xylanase WX into a low fishmeal diet;

growth was restored to a level seen with the high fishmeal
FCR & Protein Efficiency were significantly improved

Objective

• To evaluate the effect of the supplementation with a fungal xylanase (RONOZYME® WX) on growth performance and nutrient utilization in juvenile Nile tilapia (Oreochromis niloticus) fed cereals, cereals by-products and plant proteins with reduced fish meal level. 

Methodology & Trial details

• Basal Diet: Wheat middling’s, SBM,  rapeseed, corn, rice bran, cottonseed meals, fishmeal (10% & 5%)
• Experimental: Initial body weight 25g, 12-week duration
• Treatments:
• 6 treatment groups combining:
• fishmeal (FM) at 10% and 5% in the diet
• RONOZYME® WX supplementation at 0, 100 and 200 ppm
• Parameters: growth (body weight, weight gain, specific growth rate (SGR), FCR, protein efficiency ratio (PER), nutrient utilization after 9 & 12 weeks of feeding

Results:

• FCR was significantly correlated with the dietary dose of xylanase.  
• Protein efficiency ratio (PER) was significantly increased with xylanase.
• No effect of the enzyme was observed on fat and energy retention.
• Protein retention was higher for FM 10% tha FM 5% one. Its increase was significantly correlated with the dietary xylanase dose.
• Nitrogen loss was reduced in relation to the enzyme dose.
• At 10% FM, the effective dose of xylanase was 100 FXU/kg feed.
• At 5% FM, most parameters were significantly increased at the dietary dose of 200 FXU/kg feed.

Conclusion:

• When xylanase was supplemented to a low fish meal diet, growth was restored to the level of the high fish meal control group.
•  FCR & protein efficiency were significantly improved by dietary xylanase supplementation.
•  Further improvement in performance and feed efficiency can be gained by supplementing a high fish meal diet with RONOZYME® WX.
•  Dietary supplementation with the xylanase RONOZYME® WX is an effective tool to improve performance and feed efficiency of tilapia.