Growth and Developement

growth

increase in body weight until mature size is reached

growth and development divided into 2 phases

prenatal & postnatal

prenatal growth

development of tissues, organs, skeletal system, etc

hyperplasia

increase in fiber number

hypertrophy

increase in fiber size

intra-abdominal fat

deposited in abdominal cavity

subcutaneous fat

deposited under skin; backfat

intermuscular fat

fat between muscles

intramuscular fat

fat within muscles; marbling

mammal bones

long, short, flat

• epiphyseal plate

avian bones

pneumatic, medullary

nutrient partitioning; systems

nervous, circulatory, respiratory, digestive, reproductive

nutrient partitioning; tissues

skeletal, muscle, adipose

nutrients first prioritized to maintenance

30-40% growing

90% mature

remaining nutrients go towards …

growth, finishing, production, work, reproduction

positive energy balance

animal has enough nutrients to meet all needs

negative energy balance

nutrient intake does not meet the needs

• weight loss

hormone modification of growth

federal law prohibits added hormones in pork and poultry production

beta agonists

not hormones

cattle, pigs, turkeys

• phased out of swine

repartition nutrients toward muscle growth

anaerobic metablism

glucose

lower ATP yield

faster

cytoplasm

products: lactic acid

aerobic metabolism

glucose and oxygen

greater ATP yield- more energy

slower

cytoplasm and mitochondria

products; CO2, water

low exercise intensity

lots of oxygen

aerobic metablism

high energy intensity

lack of oxygen

anaerobic metabolism

build up of lactic acid

steady-state training

longer duration

lower intensity

aerobic metabolism

slow-twitch muscle- increase muscle endurance

interval training

shorter duration

higher intensity

anaerobic metabolism

fast-twitch muscle- increase muscle size

muscle ATP depletion

muscle fatigue

muscle cramps