Feed Intake & Behaviour Flashcards
Why is feed intake important in animal agriculture?
It directly affects the economics of production and net income for livestock producers.
What are the two main categories of feed supply in animal agriculture?
- Diet is supplied with little choice (e.g., pigs, chickens, dairy cows)
- Animal is responsible for feed selection (e.g., animals on range)
What is hunger?
A strong need or desire for food.
Define the term ‘appetite.’
An instinctive physical desire, especially one for food or drink.
What does ‘ad libitum’ mean?
‘At one’s pleasure’ or food is available at all times.
What is satiety?
The condition of being full or gratified beyond the point of satisfaction.
True or False: Orexigenic substances stimulate appetite.
True.
What is the role of the hypothalamus in feed intake control?
It is central for the ‘drive’ to eat and modulates peripheral organs.
What factors affect feed intake?
- Feed availability
- Feed quality
- Environment
- Animal integration with the CNS
- Gastrointestinal factors
- Hormones
- Metabolites
- Learning
What is the difference between short-term and long-term feed intake control?
- Short-term: Meal size and frequency of meals
- Long-term: Homeostasis and maintenance of body weight
Fill in the blank: The __________ is primarily concerned with meal size control.
hindbrain
What does ‘nutritional wisdom’ refer to?
The ability of animals to select a diet that meets their nutrient requirements.
What is the impact of stress on feed intake?
Mild stressors can stimulate feeding; extreme stress inhibits feed intake.
What is the main method for measuring food intake in animals?
Weigh feed supplied and weigh remaining feed after a pre-determined interval.
What is the primary challenge in measuring feed intake in group-housed animals?
Difficult to measure variability of individual intake.
What is the effect of increasing pen stocking density on heifers’ feeding behavior?
It decreases time spent eating but may not affect dry matter intake (DMI).
What dietary factor can limit a pig’s ability to consume sufficient amounts?
The bulkiness of the feed.
True or False: Chickens are able to accurately alter feed intake in response to dietary energy levels.
False.
What is the relationship between forage dry matter (DM) content and intake in Holstein Friesian cattle?
Increased DM content leads to greater forage intake and shorter times to ingest and ruminate.
What happens to zebra finches’ body mass when they carry a backpack?
They lose mass equivalent to the weight of the backpack while maintaining food intake.
What stimulates taste receptors in animals?
Dietary nutrients stimulate taste machinery in the tongue and act as nutrient sensors.
What are the mechanisms through which finches decrease body mass?
Unidentified mechanisms while maintaining dietary intake and reducing overall activity.
How do dietary nutrients elicit taste?
By stimulating the taste machinery in the tongue (taste buds, taste receptors, nerves) which in turn stimulate the gustatory cortex in the brain.
What is the current understanding of taste receptors in non-oral tissues?
They are acting as nutrient sensors away from the tongue, continuously surveying the nutritional status of the animal.
