9Ac(6)
Rare breeds
The farm animals that are now popular have been created from older breeds by the process of
selective breeding. The older breeds no longer have all the characteristics that farmers want but to
stop them from becoming extinct they are kept in rare breeds farms. For example, large work
horses (shire horses) were used to pull ploughs and heavy carts. They are not needed now
because we have tractors and other machinery to do their work.
The animals on rare breeds farms are involved in breeding programmes so that there will always
be some of these rare breeds living. It is important that their genes are not lost in case their
characteristics become popular again. Around the UK there are about 19 rare breeds farms.
Animals are said to be rare if there are only a few hundred existing. English longhorn cattle and
phoenix chickens are rare breeds.
The English longhorn was bred in the middle of the eighteenth century by Robert Bakewell who
lived in Lancashire. He was the first person to selectively breed cattle specifically for farmers. The
characteristics he selected were quick growth and large rear end (where some of the best meat is).
English longhorns were the most widely used cattle in Britain and Ireland until the early nineteenth
century. At this time the shorthorn breed became more popular.
An English longhorn cow.
Each breed of animal has a certain set of
characteristics. A breed is only a breed if all
the offspring produced have the same set of
characteristics. A breed is established by
existing for six generations or more over 75
years. If a breed has not existed this long then
it is not a proper breed and may be allowed to
die out.
A phoenix cockerel.
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9Ac(6) Rare breeds (continued)
1 How are new breeds of farm animal created?
2 a Where are old breeds kept to stop them from becoming extinct?
b Why do we keep rare breeds and not allow them to become extinct?
3 Why are shire horses no longer needed?
4 a How long does one breed have to exist for before it is properly defined as a breed?
b A farmer has some chickens which he thinks are a new breed. How would you find out if
the chickens actually are a breed?
5 a Name two characteristics that were selected for when English longhorn cattle were bred.
b Why were these characteristics useful to the farmer?
c Suggest why the shorthorn breed became more popular than the longhorn.
6 In the middle of the nineteenth century, farmers liked to show off by having a few members
of an interesting looking breed of chicken roaming around the farm. It did not matter if these
chickens were not very useful for much else.
a Which feature has been selectively bred in the phoenix breed?
b Why do you think farmers no longer bother having interesting looking chickens roaming
around?
7 Some people have suggested that the numbers of rare breeds could be increased by
cloning.
a Make a copy of the diagram below. Complete it and add labels to explain how an English
longhorn cow could be cloned.
b Suggest an advantage of cloning over traditional breeding.
c Suggest a disadvantage.
I CAN... ••
describe how and why animals are selectively bred
explain why it is important to keep them
• describe how mammals can be cloned.
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