Allometric Growth and Body Compositions Flashcards
Name which reaches maturity from earliest to latest: bone, nervous tissue, fat, daily feed intake, and muscle.
Earliest: 1) nervous tissue
2) bone
3) muscle
4) fat
Latest: 5) daily feed intake
True or False: There is not a priority of body development in animals
FALSE - There IS a priority of body development in animals.
How do body components develop at certain times?
Body components that are physiologically more important develop earlier.
Name from earliest to latest as to when these body components develop based on physiological importance: head, hands, neck, thorax, loin, feet, tibia, pelvis, and femur.
Head, Hands, Feet > Neck, Tibia > Thorax, Femur > Loin, Pelvis
Name from earliest to latest as to when these body components develop based on physiological importance: bone, fat, muscle, and brain
Brain > Bone > Muscle > Fat
What is allometry?
Allometry = growth of one component in relation to the whole
What is allometric growth the study of?
It is the study of how body parts change in size as an animal develops
Regarding allometric growth, what body parts are included?
Body parts include tissues, organs, and body components (head, limbs, thorax, etc.)
In the allometric growth theory, it discovered that if the natural logarithm of the claw weight was plotted against the natural logarithm of the weight of the body minus the claw, the resulting relationship was virtually a straight line.
How could this line be described by a formula? What does each component stand for?
Formula: y = ax^b
Y = log weight of carcass or animal
a = constant
x = log weight of tissue or component
b = growth coefficient of tissue or component (slope of line)
What are the basic principles of allometric growth theory?
1) There is a constant relationship that exists between each tissue and the whole body
2) b dictates the slope of the line reflecting the positive or negative relation of tissue or component growth with the whole
When b >1, what does that tell us regarding growth rate (tissue vs whole), growth impetus (similar to growth rate), and time of development? Provide an example.
- Growth rate (Tissue vs Whole) = Faster
- Growth Impetus = High
- Time of Development = Late
- Example = Fat
When b =1, what does that tell us regarding growth rate (tissue vs whole), growth impetus (similar to growth rate), and time of development? Provide an example.
- Growth rate (Tissue vs Whole) = Similar
- Growth Impetus = Average
- Time of Development = Middle
- Example = Total muscle
When b <1, what does that tell us regarding growth rate (tissue vs whole), growth impetus (similar to growth rate), and time of development? Provide an example.
- Growth rate (Tissue vs Whole) = Slower
- Growth Impetus = Low
- Time of Development = Early
- Example = Bone
Allometric growth curves identify the time when ________ develops.
Muscle
What is the value of b in early-developing muscles?
b < 1
What is the value of b regarding late-developing muscles? What does that tell you?
- b>1
- Tells me they develop late and faster
What is the value of b regarding average-developing muscles?
b values are closer to 1
True or False: Direction of allometric muscle growth varies between species.
True!
What is the measurement of body weight?
A measurement that involves withholding feed and water for 24 hours prior to slaughter to secure shrunken weights.
What is the measurement of empty body weight?
A measurement that’s accomplished by flushing the contents of the digestive tract and weighing the body.
What is the measurement of carcass weight?
A measurement that contains primarily muscle, bone, and fat.
What is the measurement of dressing percentage?
A measurement that involves the removal of all internal organs but the carcass, then dividing that by the live weight.
What is the measurement of carcass length?
A measurement involving the distance between the most anterior portion of the aitch bone and the first ribs
What is the measurement of longissimus muscle?
- For the cross-section area, it’s measured by the loin eye area (LEA) or ribeye area (REA).
- For diameter, it’s measured by loin depth.
