The open nucleus breeding system proposed by Cunningham in 1979 involves a central herd of 200 cows where detailed records are kept and bull selection is based on pedigree and performance. The central herd is supported by a base village herd that provides 10% of cows to the central herd annually through a selection process involving visual judgment of traits. Selected bulls from the central herd come from the best cows based on growth and dam's milk yield, and the lowest 10% of cows in the central herd are replaced with animals from the village herd which are then recorded and evaluated.

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.  Irish animal breeder Cunningham (1979) has proposed open
nucleus breeding system for developing countries;
 The plan operates around a central herd which should be preferably
under government control & carried out proper recording & breeding
practice;
 The supporting base population in the village herd which provides
cows to replace about 10% of the cows in the central herd annually;
 Selection procedure in village herd involves judgment by eyes,
milking ability, size, conformation and condition etc;
ONBS:

4.  Selected bulls comes from central herd produced from best
cows based on own growth rate & dam’s milk yield & the best
are chosen as sires;
 The lowest performing 10% animals in the central herd
replaced with new animals coming from village herd;
 The later animals are recorded during the following years with
remainder of the central herd & revaluated;
 Culled bulls & cows are given to the village people so that they
can get good animals .
ONBS: