3. The X Factor - for cows, pigs, sheep

Todays learning: (WALT)

  • Recognise that living things produce offspring of the same kind, but normally offspring vary and are not identical to their parents
  • Identify how animals and plants are adapted to suit their environment in different ways and that adaptation may lead to evolution.

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 areĀ  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

Resources:

  • Video: 'The X Factor - for cows, pigs, sheep'
  • Pupils work book 'Can Sheep read numbers?'

Outcomes: (WILF)

  • Explain how even animals with same parents are not exactly the same and will have different characteristics

Teaching notes:

.

Last modified: Monday, 25 November 2013, 7:22 PM