Dairy pt 1 Flashcards
- milk production globally - milk production in the mammary gland - milk components production
which country produces the most milk?
the EU
how does canada rank in in milk production?
11th
what are the 3 major components of the canadian economy?
grains/cereals, red meats, milk
what’s the difference between grains and cereals?
grains = hard seeds without hulls or fruits
cereals = grass cultivated for the edible components of its grain; composed of endosperm, germ, and bran
what are the 2 major provinces that produce milk?
Quebec, Ontario (make 75% of milk in canada)
what are the 3 major milk/dairy producers?
Agropur, pharmalat, saputo
how much is produced/processed as fluid milkl?
40%
define a heifer
young cow that hasn’t yet made a calf
why does milk composition vary between mammals?
nature of the animal’s diet
why is the protein content of human milk lower than others?
immunity; adaptation; mother diet
what are the essential amino acids?
- threonine
- histidine
- isoleucine
- leucine
- lysine
- methionine
- phenylalanine
- valine
- tryptophan
what are the main components of milk?
- proteins
- CHO
- fats
- moisture
- others (vits & mins)
what hormone is required for milk production?
oxytocin
what are the small vesicles in the mammary glands called? what kind of cells are there?
alveoli; secretory cells
describe the process involving oxytocin and the production of milk
oxytocin binds to the secretory cells in the alveoli which makes them expel fluid into the lumen (alveoli cavity)
where a fat globules synthesized?
ER
what milk proteins are produced in ribosomes?
major ones: B-lactalbumin, B-lactoglobulin
what milk proteins are produced elsewhere (i.e. liver)?
minor ones: albumin, immunoglobulins
how are electrolytes transported?
via pumps or channels through lateral membranes connecting epithelial cells in the lumen
where are proteins phosphorylated/glycosylated?
golgi appartus
where is lactose synthesized?
cytosol
trying to make lactose: what happens to glucose that can’t pass through the golgi membrane?
glucose is epimerized into galactose on UDP as UDP galactose
what’s UDP galactose? where does it go? how?
the epimerized version of glucose; into the golgi lumen by active transport
what intermediate ultimately gets turned into lactose? what enzyme is responsible for this transformation?
UDP-galactose; galactose transferase
what breed of cow is the most prominent in canada for milk production? what percentage do they contribute?
Holsteins; 93%
what’s the benefit of using holsteins for milk production?
produce the most milk per cow and contribute the most volume
what substance naturally increases milk production volume?
hormone: bovine somatotropin (bST)
how is bST obtained?
take gene from cow, stick in bacteria (E. coli) and let them rapidly grow and produce the hormone
why isn’t use of bST approved everywhere?
can cause allergic reactions in humans and reduces fertility of the cows so they don’t conceive as easily in its presence
