The Effect of Animal and Plant Protein-Based Diets on the Crude Protein Requirement of Cockerel Starters

Abstract

The efiect of dietary protein sources on the crude proteirz (CP) requirement of the Black Olympian cockerel starters
was studied in an experiment that lasted for5 weeks. Diet dilution technique was employed toforntulate suvnrnit
diets (SD) I and I1 based on alzimal and plant protein sources and containing CP of 280.4ghg and 281g.g on asfed
basis respectively and a low-protein (25.6flgCP) dilution mixture (DM). Both SDs and DM contained
2600kcal ME&. Each SD was serially diluted with DM to produce the treatment diets containing 180,200,220,240
nrzd 2 6 0 f l g CP. Two coniniercial dies were also included @r comparisoiz) to make a total of 12 treatment diets.
They were fed ad libitum to a total of 192 birds.
Mean daily weiglzt gain and feed conversion ratio were improved (Pc0.05) as dietanj protein level increased,
especially with the plant protein-based diets. Birds receiving diet F(18%CP plant protein-diet) had fhe poorest
(P4.05) daily weight gain and feed conversion ratio compared zoitlz diets B(anima1 protein-based) and I (plant
protcirz-based) wlziclz satisfied the protein requiremeizt of the birds for optimal performance. Feed cost per ztrzit
zl~eiglitg ain on diet B zi~lzichc oiztained 20% CP aizd diet 1 wlziclz contained 24%CP were alniost tlze sante and
clicnpcr than with any other diets. It is therefore concltided that 20 and 24CP levels in the animal and plant profeinhnscd
diets respectively zooiild sntisfij flze protein requirement of cockerel strrrters for optimal p w t l z rate at minimal
cost offceilirlgp er ~rnitgai~zV.a nation in tlze recommendeil reqzrirenzeizt values by differenta uthors is partly dtie
to the qzlnlity of dzetary protein sozirces as exenzplifieil by fish rtieal and bloodmeal versus soyabean men1 and
groz~ndniltc ake-based diets zised presently. This should be borne in tlze minds of poultn~~farrnearnsd feed millers
alikc.