9. Feed Intake

Question 1

Intake regulating signals are integrated in the

Answer 1

Hypothalamus
Peripheral neural receptors: stimulate hypothalamus
receptors in liver, GI tract, skin
chemoreceptors, tension receptors, thermoreceptors
secretion od peptides / hormones that act directly on the hypothalamus
peptides from gut, adipose, brain

additive effect of these feedback mechanisms controls intake

Question 2

Feed intake regulation

Answer 2

Metabolic control of intake
-circulating nutrients
-peripheral neural receptors in liver and GI tract
-tell animal lots or little of nutrients in blood/ gut

Monogastrics: glucose most likely nutrient
Ruminants: acetate and propionate from rumen most likely
animals feel hungry when these nutrient concentrations decline

animals with high requirements strive to eat more
they eat more after starvation or excercise

Question 3

Feed intake regulation; Animals

Answer 3

lipostatic regulation of feed intake lost in many domestic animal species
desire to maintain constant body weight or fatness
wild animals rarely obese
poultry reduce intake after period of force feeding

leptin: hormone produced by adipose tissue important for lipstatic control of feed intake - the satiety factor
adipose tissue in abdomen reduces intake
fatty acids in liver disrupt peripheral neural receptor system that initiates feeding