Open Nucleus Breeding System (ONBS)

Open Nucleus Breeding Scheme (Cunningham, 1979)

1. Open Nucleus Breeding
System/ Strategy

2. Nucleus Herd
200 cows
Detailed record kept
Bull selection based
on pedigree &
performance
10%
culled
Recording
& AI
scheme
involved
20
selected
cows
Bulls
AI
NS
VH
VH
VH
VH
Open Nucleus Breeding
Scheme (Cunningham, 1979)
Proper recording , genetic evaluation, breeding design,
replacement , culling should be practiced in the central herd
Simple record
keeping practiced in
the village herd

3. IrishanimalbreederCunningham(1979)hasproposedopen
nucleusbreedingsystemfordevelopingcountries;
Theplanoperatesaroundacentralherdwhichshouldbepreferably
undergovernmentcontrol&carriedoutproperrecording&breeding
practice;
Thesupportingbasepopulationinthevillageherdwhichprovides
cowstoreplaceabout10%ofthecowsinthecentralherdannually;
Selectionprocedureinvillageherdinvolvesjudgmentbyeyes,
milkingability,size,conformationandconditionetc;
ONBS:

4. Selectedbullscomesfromcentralherdproducedfrombest
cowsbasedonowngrowthrate&dam’smilkyield&thebest
arechosenassires;
Thelowestperforming10%animalsinthecentralherd
replacedwithnewanimalscomingfromvillageherd;
Thelateranimalsarerecordedduringthefollowingyearswith
remainderofthecentralherd&revaluated;
Culledbulls&cowsaregiventothevillagepeoplesothatthey
cangetgoodanimals.
ONBS: