Actually Feeding Animals Flashcards
Diet formulation: what four things do we need to know?
- Nutrient requirements of the animal (knowledge of physiological state/body weight).
- Chemical composition of available feedstuffs.
- Appetite (voluntary food intake/ dry matter intake)
- Feedcosts
Define ‘ad libitum’.
Animals fed as much as they like; generally in production systems.
What can influence an animals appetite?
- Palatability
- Fibre content
- Season
- Age
- Production level
- Abdominal space
- Food choice
- Feed preparation
- Physiological mechanisms
Estimating appetite: rules of thumb.
~3% of body weight as DM
How do you use Pearson’s square?
- Put the desired value in the centre of the square
- Place the values for each of the 2 feeds in the left hand corners.
- Subtract the smaller value from the larger and put this figure in the diagonal right hand corner (the calculated figures on the right are called parts).
- Add the individual parts to determine the total parts.
- Change the individual parts to percentages of the final (total) mix (individual food parts/ total parts) x 100 = % of that food in total ration.
What is Pearson’s Square method used for?
- It is a method for balancing a nutrient requirement with two available feed ingredients.
- Used to formulate animal feed to meet specific nutrient percentages.
A poultry unit manager wishes to fill the feed hopper for the weekend using ground wheat & fishmeal
The laying hens need 200 kg of feed DM with an overall CP of 15%.
Ground wheat has a CP of 12.4% & is 86% DM
Fishmeal has a CP of 72%
& is 92% DM
222.4 kg FW
9.48 kg FW
Recall the water requirements rule of thumb.
Maintenance fluid requirements of adult animal = 50 ml / kg / day
What management fact influence ration consumed in practice?
Human errors
Practical issues
Preparation (mixed correctly)
Foreign objects
Contamination of feeds (mouldy, toxins etc)
Quality of feeds
Truly “ad lib”?
Trough design
Feed space and building design (bullying)
