植酸酶預(yù)處理對尼羅羅非魚生長及磷代謝的影響.pdf

1、華中農(nóng)業(yè)大學(xué)碩士學(xué)位論文植酸酶預(yù)處理對尼羅羅非魚生長及磷代謝的影響姓名：曹玲申請學(xué)位級別：碩士專業(yè)：水產(chǎn)養(yǎng)殖指導(dǎo)教師：王衛(wèi)民楊毅20070601華中農(nóng)業(yè)大學(xué)2007屆碩士學(xué)位論文Fourpretreatmenttrialswereconductedtotreatsoybeanmealwheatmeal，cornglutenmealandmixedplantmeal(soybcallmeal，wheatmealandcornglutenm

2、ixture)withphytasetodeterminetheoptimaldoseofphytaseForthefirstthreemealsthegradedadditiondosagesofphytasewereallat0，500，750，1000，and1500U／kgrespectivelyForthemixturemeal，thegradedadditiondosagesofphytasewereat0，500，750，

3、1000and3000U／kgrespectivelyResultsshowedthattheavailablephosphorouslevelsincreasedsignificantlywiththeincreaseddosesofphytaseinfourexperimentalmeals，andrevealedthatthedoseof1，0∞U／kgwasmostefficientamongallsupplementaldos

4、agesBased011thepretreatmenttrials，allplantdietswereformulatedbytreatingplantingredientsusingphytaseat1000U／l【gThetreatmentdietsweresupplementedwithmonocalciumphosphate(MCP)at25％(Diet3)，‘1875％plet4)，125％①iet5)，0625％(Dict6

5、)andO％(Dict7)forNiletilapia硒experimentaltreatmentsInaddition，therewerethreecontrols：onephytasecontrolwithoutphytasepretreatmentnorinorganicphosphoroussupplement(Diet1)；OIlCinorganicphosphorouscontrolwithoutphytasepretrea

6、tmentbut州th25％MCPsupplement(Diet2)；andonepretreatmentcontrol∞ict8)withoutphytasepretreatmentnorMCPsupplementbutaddingphytasedirectlytofeedingredientsatadoseof1000U／kgbydissolvingphytaseindistilledwamrbeforepelletingAllex

7、perimentaldiets(bothtreatmentandcontroldiets)wereformulatedtocontainapproximately364％crudeproteinTheresultsshowedthatthedietspretreatedwithphytase(Dict37)gavebettergrowthperformance，feedconversionratioandproteinefficienc

8、yratioofNiletilapiathanphytasecontroldietpiet1)(P(005)Therewasnosignificantdifferenceamongthedietspretreatedwithphytaseatdosesof25％1875％and125％ofrequiredavailablephosphorus(P005)，whichresultedinsignificantlybeHerperforma

9、ncethanthoseatdosesofO625％and0％(P005)AdigestibilitytrialwasconductedattheendofthegrowthtrialApparentdigestibilitycoefficient(ADC)ofphosphorouswasimprovedsignificantlybythephytasepretreatment(P005)Nosignificantdi矗erenccwa

10、sdetected011ADCofcrudeproteinamongallexperimentaldiets(D帕05)Itc粗beconcludedfromthepresentstudythatphytase啪beusedtoefficientlypretreatallplantbaseddietsatadoseof1000U／kgwhileinorganicphosphoruscanbesupplementedat125％ofMCP

11、toensurethattheadequatcamountofphosphorusisavailabletojuvenileNiletilapiameanwhiletoimprovetheirfeedefficiencyfishqualityandchemicalcompositionandthusenhancephosphorousutilizationandphosphorousretentionKeywords：Microbial