NUTR 3000 - Patterns of Growth

In production animals, the endpoint for growth is at

maturity

There are internal and external factors to growth such as

Internal: genetics

External: diet, environment

Growth definition

an increase in body mass over a period of time at a rate that is is characteristic for a particular species that has a set endpoint for that species

Typically, a growth curve is a _____________________ shape

sigmoidal

How does the rate of growth change with an S curve

growth starts slow after birth, then rapidly accelerates, then slows again as the animal reaches maturity

In aquatic species, the growth curve can be

exponential

What is the point of inflection in the growth curve

the junction of the early phase of increasing growth rate and the later phase of decreasing growth rate (where the animal reaches its maximal rate of gain)

At the point of inflection, there will be

puberty

slowed growth

increased fat depo

meat and bone growth rate decrease

the best time economically to eat your animal would be at the

point of inflection

If you want marbled meat, you should

wait to slaughter after maturity/point of inflection

Isometric growth

all tissues grow at the same rate

ex: fish (little fish looks the same as big fish)

Allometric growth

different art of the body grow at different rates

ex: horses (foals are all legs)

Growth impetus

the order of development of different tissues in the body

Low growth impetus

develops early in life, early maturing, with slow postnatal (particularly bone) growth

Animal with low growth impetus

chicken

High growth impetus

late maturing, reaching full development later in life, particularly fat

Animal with high growth impetus

cow

Tissue growth impetusses order

Low to high:

bone

fat

muscle

carcass

ie bone growths before fat

At an early age, most of an animals body weight gain is

protein and water

at a mature age, most body weight gain is

fat

as an animal grows, ___________ and ___________ increase rapidly.

______________ increases moderately.

__________ changes little

water and fat

protein

ash

Compensatory growth

increased growth rate to compensate for previous undernourishment (so long as maturity hasn't yet been reached, you can make up for malnutrition)

Give an example of compensatory growth in fish and how this can be economical for us.

Fish can be fed low EPA and DHAA then fed lots right before maturity and they compensate and then they have good EPA and DHA ammounts for human consumption. This saves the ammount of EPA DHA we have to feed