Quiz 7 Flashcards
energy requirements
- body size.
- breed
- Activity
- diurnal rhythm
- environmental temperature
- diet
- level of production
- feather coverage
body size
larger birds have lower energy requirement
breed
purpose of the breed effects energy requirement
activity
birds with access to more space have higher energy requirements
diurnal rhythm
the longer the dark period the less active the birds is
environmental temperature
the cold- a greater energy requirement to produce heat
the heat- higher energy requirement to dispel heat
diet
composition of diet affects energy needed to utilize other nutrients
level of production
higher producing birds will lead to higher production requirments
feather coverage
less feathers= higher energy requirements
calorie
amount of energy needed to raise 1 g of 1 degree
gross energy
total combustible energy in a feedstuff
- measured by a bomb calorimeter
digestible energy
the portion of gross energy not found in the feces
- not used in poultry
metabolizable energy
the portion of gross energy not lost in feces, gases, and urine.
- gas production is negligible in poultry
- most commonly used in poultry
net energy
the energy that is available for maintenance and production
- takes heat losses into account
true vs apparent metabolizable energy
true ME take into account endogenous energy losses in the feces and urine while apparent ME does not.
dietary carbs
- glucose is the primary source of energy in diets as starch. birds cannot breakdown cellulose and hemicellulose
dietary lipids
2.25 times as much energy as carbs per unit when oxidated
- derived from rendering, restaurant greases, vegetable oil industry
essential fatty acids
needed for specific functions
- linoleic and arachidonic acid
if missing dietary lipids from the diet birds exhibit…
- poor growth
- fatty livers
- reduced egg size
- reduced hatchability
Protein
crude protein- measures the amount of nitrogen present.
CP= Nx6.25
essential amino acids
have to be in the diet because the body cannot produce them.
conditionally essential amino acids
amino acids that can be synthesized by the body but may become essential depending on the condition
nonessential amino acids
can be synthesized by the body at a high rate for their need
- if provided enough N in the diet
Important essential amino acids in poultry
Threonine, tryptophan, methionine, lysine
factors affecting amino acids requirements
- more intensive production
- rate of growth/ intensity of egg production
- amino acid relationships
amino acid relationships
-phenylalanine is needed for tyrosine synthesis
- methionine is needed for cysteine synthesis
- glycine and serine can be interconverted
Antagonisms
adding extra of one amino acid can increase the requirement of another
inbalances
if supplementing individuals amino acids you must know which amino acid is most limiting, second most, etc…
Available
digestibility/ ability to be abosorbed
borderline protein deficiency symptoms
- poor growth, poor feathering, reduced egg size, poor egg production, poor feed efficiency
severe protein deficiency symptoms
- stop eating, stop egg production, loss of body weight, stasis of digestive tract, death
macrominerals
required in relatively large amounts in diets
trace minerals
required in relatively small amounts in diet
calcium deficiency
reduced growth, reduced egg production, soft-shell eggs, reduced bone mineralization.
phosphorus deficiency
weakened bones, leg problems
Calcium: Phosphorus ratio
broilers/replacement pullets- 2:1
laying hens= 8-12:1
sodium deficiency
reduced blood pressure, reduced blood pressure, reduced cardiac output
chloride deficiency
lack of controlled mov’t , nervousness
potassium deficiency
muscle weakness, heart and respiratory problems, intestinal distension
magnessium deficiency
slow growth, lethargy, panting, gasping
copper deficiency
anemia, weakened bones, lameness, aortic rupture (turkeys)
iodine deficiency
reduced growth, reduced egg production, increased fat deposition ( obesity)
iron deficiency
anemia
manganese deficiency
perosis( slipped tendon), reduced egg production, reduced shell fitness, reduced hatchability of fertilized eggs
selenium deficiency
ruffled feathers, unthriftiness, frequent bruising, edema, exudative diathesis, white gizzard disease ( turkeys)
zinc deficiency
slower growth, shorter leg bones, enlarged hock joints, scaly skin, poor feathering, loss of appetite
vitamins
organic compounds required in diet in small amounts for life.
vitamin A deficiency
disruption of mucous membranes with white pustules, slower growth, emaciation, weakness, conjunctivitis, staggered gait
vitamin D deficency
decrease egg production and shell quality, bone weakness with increased breakage, reduced hatchability
