cao, ling and james diana university of michigan wang weimin huazhong agricultural university
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Effects of pretreatment in all-plant feedstuff with microbial phytase on phosphorous utilization and growth performance of Nile tilapia. Cao, Ling and James Diana University of Michigan Wang Weimin Huazhong Agricultural University Wuhan China Yang Yi Shanghai Ocean University - PowerPoint PPT PresentationTRANSCRIPT
Effects of pretreatment in all-plant feedstuff wiEffects of pretreatment in all-plant feedstuff with microbial phytaseth microbial phytase
on phosphorous utilization and growth perforon phosphorous utilization and growth performance of Nile tilapiamance of Nile tilapia
Cao, Ling and James DianaCao, Ling and James Diana
University of MichiganUniversity of Michigan
Wang WeiminWang Weimin
Huazhong Agricultural UniversityHuazhong Agricultural University
Wuhan ChinaWuhan China
Yang YiYang Yi
Shanghai Ocean UniversityShanghai Ocean University
Shanghai ChinaShanghai China
AquaFish CRSPAquaFish CRSPUSAIDUSAID
Travel funding for this presentation was provideTravel funding for this presentation was provide
d byd by AquaFish AquaFish
Collaborative Research SuCollaborative Research Support Programpport Program
The Aquaculture CRSP is funded in part by United States Agency for The Aquaculture CRSP is funded in part by United States Agency for International International
Development (USAID) Grant No. EPP-A-00-06-00012-00.Development (USAID) Grant No. EPP-A-00-06-00012-00.
The opinions expressed herein are those of the authors and do not The opinions expressed herein are those of the authors and do not necessarily reflect the views of the US Agency for International necessarily reflect the views of the US Agency for International
Development.Development.
OutlineOutline
BackgroundBackground Experimental designExperimental design ResultsResults ConclusionsConclusions AcknowledgementAcknowledgement
1. Background1. Background
Decrease of annual fishmeal productionFishmeal substitution by plant proteinsHigh concentration of phytate in plant proteins
Phytate and phytase enzymePhytate and phytase enzyme
Phytate = phytin = phytic acid
Up to 80% of the total P content in plants may be present in the form of phytate and is practically not available for monogastric or agastric aquatic animals.
Table 1. Phytate contents in plants or plant products (NRC, 1993)
Phytase: Phytase: An enzyme specific to hydrolyze phytate, naturAn enzyme specific to hydrolyze phytate, natur
ally found in animals, plants and microorganisally found in animals, plants and microorganismsms
Figure 1. Action of phytase (Baruah et al. 2004)
Table 3. Commercial information of microbial phytase Table 3. Commercial information of microbial phytase (Cao (Cao et alet al. 2007). 2007)
Table 4. Optimum dose of phytase addition in diets of different fish species (Cao et al. 2007)
2. Experimental design2. Experimental design
2.1 Pretreatment trial2.1 Pretreatment trial
Objectives:Objectives:
** Find out the most efficient phytase dose for trFind out the most efficient phytase dose for treating plant ingredientseating plant ingredients
Citric acid bufferCitric acid bufferPhytase (5000 U/g)Phytase (5000 U/g)
pH pH 5.55.5
Enzyme solution Enzyme solution (10 U/ml)(10 U/ml)
Mix with plaMix with plant ingrediennt ingredients (W:V=1:1)ts (W:V=1:1)
Oven 55 Oven 55 ℃℃ 55 ~~ 6 h6 h
SamplinSampling g
Chlorine anion 100-200 mesh AGChlorine anion 100-200 mesh AG1-X4 1-X4 (( Bio-Rad Laboratory, USBio-Rad Laboratory, USAA ))
2.2 Growth trial2.2 Growth trial
Objectives: Objectives:
** Find out the optimum addition dosage for groFind out the optimum addition dosage for growth performance of tilapia juveniles. wth performance of tilapia juveniles.
** Determine the best replacing amount for inorDetermine the best replacing amount for inorganic phosphorous by phytase.ganic phosphorous by phytase.
3. Results 3. Results
3.1 Pretreatment3.1 Pretreatment
Soybean mealSoybean mealMix plant ingredientsMix plant ingredients
3.2 Growth performance3.2 Growth performance
4. Conclusion4. Conclusion
The optimal dose of phytase for the pretreatment of plant ingredients is 1,000 U kg -1, which can efficiently convert phytate P to available P and replace 50% of the inorganic P supplementation to the diets for Nile tilapia juveniles without affecting their growth performance, apparent digestibility coefficients of both crude protein and phosphorous.
The addition of phytase in the diets can reduce the use of inorganic P, enhance the utilization of P in plant ingredients, and thus minimize the P discharge to the environment.