feeding behavior Flashcards
appetitive vs consummatory behaviors
appetitive = searching for food
* learned
* stalking, scratching ground, walking btwn patches of bushes
consummatory = eating food
* manipulating, digesting
* innate
* species-specific
appetitive vs consummatory behavior influences
internal: both B involve complex biological, physiological, & neurological processes
- biological ➞ tameness
- physiological ➞ GI
- neuro ➞ pathways regulating hunger, satiety, etc
external:
- envir (food availability/accessibility)
- predators
- competition
ruminants
- herbivores:
- grazing ➞ grass
- browsing ➞ leaves & shrubs
- cycles of grazing/browsing, resting, & regurgitating
- GI can break down cellulose ➞ designed to get max amount of nutrients from tough plant material
areas’ impacts on feeding behaviors
- grazer vs browser ➞ what food source is available in the envir
- obstacles in envir
- available hiding space
- weather ➞ i.e. grazing during cool & resting during hot
- predators & how they find prey
Mendocino blacktail deer: environmental influence on feeding behavior
- lives in forests w/ lots of shrubs/leaves as food source ➞ suitable to browsing feeding behavior
- predator = puma ➞ ambush hunter that relies on vision
- puma’s appetitive B: stalking, hiding
- forests have lots of hiding places hide from pumpa so can rest & ruminate
- lowest mortality within familiar home-range ➞ deer know hiding spaces
- must be solitary to hide efficiently (groups cannot hide well in forests) ∴ browsers = solitary
elk in yellowstone: environmental influence on feeding behavior
- yellowstone has open fields with expansive grass for grazing
- large home-range, all the same resources, no one area better than other
- rotate grazing area b/c of large herds & seasonal conditions
- predators = wolves ➞ use olfactory cues & hunt in large groups
- no spaces to hide
- wolves will track regardless of hiding spaces ➞ solidarity in numbers = best strategy
- dilution effect: ↑ in group # = ↓ in chanced of being eaten
choosing where & when to eat
how long it takes to find food (appetitive)
* spatial distribution: located near or far & the principle of allocation
* temporal distribution: when the food is available
* variation in season
* ex: predators that feed on offspring must wait until birthing season
* strategy:
* diff amounts of energy depending on each food source
* prey choose based on predator strategy
* predator B based on energy: carcass vs capturing live prey
* competition influences when/where/what to eat
* knowing of competition can ↑ speed
* predation ➞ available source is less available
type of food (consummatory)
* quality ➞ energy provided by food
* ex: nuts provide more nutrients than cellery
* effort ➞ work-time/digestibility of food
domestic vs wild-type feeding behavior
- feeding B can communicate reproductive quality
- ex: wild chicken call louder & more frequently for best food source
- spatial distribution
- ex: domestic chx choose easily accessible food while wild exhibit contra-freeloading
- effects of patchiness
- separate housing in sows ➞ electronic feeders
- competition for food influences producer feeding
- electronic feeders
- separate housing
- grazing seasons: ex: sheep ➔ clovers rich in fatty acids ➞ producers alter methods
domestic vs wild-type feeding behavior
- feeding B can communicate reproductive quality
- ex: wild chicken call louder & more frequently for best food source
- spatial distribution
- ex: domestic chx choose easily accessible food while wild = contra-feeloading
- effects of patchiness for grazers
- separate housing in sows ➞ electronic feeders
- competition for food influences producer feeding
- electronic feeders
- separate housing
- grazing seasons: ex: sheep ➔ clovers rich in fatty acids ➞ producers alter methods
- predation ➞ coyotes attacking livestock ➞ roaming/grazing animals
optimal foraging theory
to maximize fitness animals must choose the feeding B strategy where benefits > costs
* costs = energy used to find, capture, & consume food
* benefits = energy content/return
* ex: shore crabs feeding on muscles
* small muscles have little energy but require opening ∴ costs > benefits
* large ones = too hard to open ∴ costs > benefits
* med size = balance between energy invested & energy gained
* ex: horses eat tall grass w/ more reward per bite ➞ tall grass has more energy
optimal foraging behavior & domestic animals
- often contradicts OFT
- ex: dogs
- if amount of energy is the same in both kibble & meat: dog should choose kibble b/c less energy spent getting it
- domestic dogs who prefer meat that is farther away than kibble show feeding B that contradict OFT
non-optimal foraging behavior
contrafreeloading: animal chooses to work for food when identical food = easy to get
* opposite relationship between hunger & contrafreeloading
* ↑ hunger = ↓ contrafreeloading
* ↓ hunger = ↑ contrafreeloading
* might show non-optimal foraging B to:
* gain info
* gain stimulation
wild-type vs domestic diets:
parrots
appetitive B: searching for nuts/seeds
consummatory B: scratching, clawing, pecking, picking, everything required to open & consume food
wild:
* long consummatory time: use claws & beaks to break open large seeds/nuts
* podomandibulation: need to use all of body to manipulate into right position
captive:
* small nutrient-rich pellets that are best for their GI
* spend <1h/d feeding easily availible small pellets
* show ABRs
* feather-plucking
* route-tracing
* prefer oversized pellets ➞ can manipulate
* nutritional costs > benefits ➞ non-optimal
* psychological benefits > energetic costs
* show contrafreeloading: will lift heavy lid to get oversized ones when small nutritionally equivalent ones available for free
feedlot cattle contrafreeloading behavior
- feedlot cattle fed low fiber diets
- concentrate = corn, grains
- can cause liver damage ➞ causes changes in rumen bacteria
- bacteria produce lactic acid ➞ rumen pH drops ➞ acidosis
- can lead to abscesses/liver damage
- select fiber or grains by sorting & picking out with tongue & mouth (seen most when cattle have acidosis)
- contrafreeloading behavior in steers:
- group A
- open feed bunk 80% concentrate 20% hay
- closed feed bunk 100% hay
- group B had 100% hay in both open & closed
-
steers from both groups open gates to access better resources
- group A much faster to open closed gate
- group B opened gate for info
- group A
appetitive behavior: walking up to feed bunk & looking
