Lesson Activities / Tasks

• VIDEO: 'The X Factor - for cows, pigs, sheep'
• Video Dialog

• So what characteristics of cows, pigs or sheep do you think gives them the X Factor for farmers?

• Well farmers want lots of meat if the cows are kept for meat

• Or lots of milk if the cow is kept for milking.

• Just like calves with brown parents are  not quite all the same brown colour

• or piglets in the same litter with the same parents are not all the same

• Not all cows produce the same amount of milk.

• Not all pigs grow at the same rate or reach the best weight to slaughter for bacon on the same day.

• Some will grow faster and reach the weight quicker eating less food.

• The calves from the cow which produces more milk will usually also produce more milk

• The piglets from the sow which grew quickest will also grow quicker

• Cows, pigs and sheep like all animals eventually get to old to produce young so the farmer must keep some animals as replacements for those that get too old

• So when a farmer has to pick which of his animals he will use for replacement breeding animals which do you think he should choose?

• Well the farmer selects the animals that produced the most milk or reached slaughter weight the quickest

• 20 year ago cows used to produce around 13 litres of milk each day.....

• By only keeping calves from cows who produce the most milk farmers have breed cows that can produce 20 litres of milk in a day - that's this many cartons of milk in 1 day!!!

• This is called selective breeding or artificial selection, artificial because the farmer selects which animals can do the breeding and have young.

• This use of artificial selection has helped farmers produce more food and at a lower cost.

• Complete relevant section of pupil workbook.

• Plenary

• Do quiz for first section answers