Experiment solutions

1. The variable that was changed?

Source of protein used.

2. The variable that was measured?

Liveweight gain.

3. The variables that were kept the same?

Same energy content and 18% protein.

4. Why do pregnant ewes require extra concentrate feeding in the last two months of gestation?

  • Steaming up.
  • 75% foetal growth occurs in the last six to eight weeks of gestation.
  • Prevent twin lamb disease (pregnancy toxaemia).
  • Short questions

    Q1 Name a ration ingredient used to add protein to the ration and state why this is a particularly useful source of protein

  • Soya bean meal - high energy.
  • Protein helps repair and grow cells.
  • Soya meal is a good source of essential amino acids such as lysine.
  • Q2 Why is maize an excellent source of energy in a ration?

    Maize is carbohydrate, a source of starch and therefore an excellent source of energy with a low risk of causing acidosis.

    Q3 Feed company on farm

    Multiple different examples.

    Structured questions

    Q1 Using Table 1, rank the top three ingredients used in concentrates in order of protein content (starting with the highest)?

  • Soya bean meal.
  • Rapeseed meal.
  • Maize distillers.
  • Q2 Why are wheat and barley rolled before inclusion in ration formulations?

    These cereals are rolled to crack and break the grain kernel to allow easier access to the nutrient rich centre of the grain by microbes in the ruminants digestive system.

    Q3 Name the type of animal and the target energy density figure that each of the following

    UFL: Suckler/Dairy cows - Target energy: 0.94UFL

    UFV: Finishing bulls/steers/heifers - Target energy: 1UFV

    Q4 Using table 1, suggest which ingredient is an outlier and justify your answer with reference to data from the table.

    Outlier: molasses - lower DM% than other ingredients, low crude protein and no fibre.

    Synoptic questions

    Considering the price of maize is 30 to 40% more than barley, comment referring to the energy values in Table 1.

    Comment to the value of these in:

    (i) a growing animals diet:

    From Table 1, the UFL value is higher in maize grain 1.05 and maize distillers 1.03 when compared with barley which has a 1UFL value. Maize distillers is a good source of protein 26.6% which is important in a growing animal’s diet.

    (ii) a finisher diet:

    From Table 1, the UFV of 1 for barley and maize distillers. A slightly higher UFV of 1.04 which leads to better LWG. Again maize distillers is a good source of protein which is important in a finishers diet as excess carbohydrate can lead to fat being laid down on the carcase.

    (iii) a milking cows diet:

    From Table 1, the UFL value is higher in maize grain 1.05 and maize distillers 1.03 when compared with barley which has a 1UFL value. Maize distillers is a good source of protein 26.6% which is important in a lactating animals diet as protein content in the diet will produce higher protein content in milk.