Dairy Cattle Flashcards
does all dairy come from cattle?
no, it can also come from goats and sheep and all sorts of animals around the world
what is the main product of dairy cows?
> 90% fluid milk
where are most dairy farms found in the US?
up north and in CA
what is the average dairy herd size?
115 milking cows
what is the herd size of 74% of dairy farms though?
fewer than 100 milking cows
how much milk is produced by the dairies with over 100 cows?
85% of total milk production
which state has the most diary herds?
Wisconsin
why has milk production increased with fewer cows over time?
more efficient cattle, better nutrition
how is milk quantity measured?
in pounds (lbs)
what are the products from dairy cows?
fluid milk 45%
fermented/frozen products 55%
what does homogenized milk mean?
homogenizing is a mechanical process of breaking down fat
list 3 fluid milk products
low fat
half and half
whipping cream
has milk consumption increased or decreased over time?
decreased
list 3 fermented milk products
cheese
butter
yogurt
list 3 frozen milk products
frozen yogurt
ice cream
ice milk
what does lactic acid do for milk preservation?
lower pH
what is rennet?
an enzyme, comes from abomasum of calves or thistle, aids in coagulation of milk
what is the first step in cheese production?
raw milk is pasteurized to get rid of unwanted bacteria
what happens in standardization, filtration, and coagulation of cheese production?
pasteurized milk is further filtered to clean, rennet is added for coagulation, fermenting organisms are added, and milk is curdled into curds and whey
what happens to curds and whey in cheese production?
they cut, stirred, and cooked, and then whey is drained out and processed into protein powder
what happens to the curds after the whey is drained out in cheese production?
they are milled and salted, and fresh (cottage and cream) cheese is separated out
what happens after fresh cheese is sorted out?
the rest of the cheese is poured into molds, pressed, ripened, and matured
how much has cheese production increased over the last 30 years?
it has doubled as cheese consumption is increasing
what do the fermenting organisms that are added to cheese do?
convert lactate to lactic acid, which lowers pH, aiding in preservation and the tangy taste of cheese
what are the 3 main components of cheese?
water, fat, proteins
what are the 7 common goat cheese?
cottage, pot cheese, Neufchatel, cream cheese, Romano, Provolone, Blue cheese
what are the 4 common sheep cheeses?
Feta, Manchego, Romano, Roquefort
what common cheese is produced by both sheep and goats?
Romano
how much more cheese is produced per pound of sheep milk than cow milk?
twice as much per lb of sheep milk than cow milk
how much more does sheep milk cost than cow milk?
4 times as much
what country is the top butter consumer?
France
what is the “good” bacteria in yogurt?
streptococcus lactus
what country is the top ice cream consumer?
America
what is the milk fat percentage of humans?
3.7%
what is the milk fat percentage of cows?
4.0%
what is the milk fat percentage of mares?
1.3%
what is the milk fat percentage of sows?
5.3%
what is the milk fat percentage of cats?
3.3%
what is the milk fat percentage of dogs?
8.3%
what is the milk fat percentage of sheep?
5.4%
what is the milk fat percentage of goats?
4.1%
what is the milk fat percentage of elephants?
15.8%
what is the milk fat percentage of reindeer?
18.7%
what is the milk fat percentage of seals?
30-40%
what is the milk fat percentage of whales?
25-50%
how many pounds of milk does one cow produce per 305 day lactation?
24,000 “oof”
how many GALLONS of milk does one cow produce per 305 day lactation?
2730
how many gallons of milk does one cow produce per day?
8.9
what are the 5 most common dairy breeds?
Aryshire, Brown Swiss, Guernsey, Holstein, Jersey
where are Aryshire cows from and what is their nickname?
Scotland, “aristocrats of dairy”
what are Aryshire cows known for?
being very hardy and adaptable, and pretty :)
what color are Aryshire cows?
red/brown and white
what was done as marketing for Aryshire cows?
they were walked from Vermont to Missouri, calving and milking along the way
where are Brown Swiss cows from?
Switzerland
what are Brown Swiss cows known for?
being very docile, they are believed to be the oldest breed
what is special about Brown Swiss cow milk?
it has a high protein to fat ratio, so it’s good for making cheese (Swiss cheese! anyone? anyone?)
how big are adult Brown Swiss cows?
about avg. 1,000lbs
where are Guernsey cows from, and what is their nickname and why?
Isle of Guernsey in the English Channel, and “Golden Guernsey” for their milk
what color is Guernsey milk and why?
golden, from all the beta ceratine and vitamin A in their milk
what doe Guernsey cows look like?
larger, red and white
where are Holstein cows from and what is their importance in the US?
the Netherlands, and they are the most prominent dairy breed in the US
what is special about Holstein milk production?
they have the highest milk volume/production of all the dairy breeds
what size are Holsteins?
BIG,
avg adult is 1200-1500lbs
where are Jersey cows from?
the English Channel
what is special about Jersey milk and why is that important?
it has a high fat and protein content, good for butter
how big are Jerseys?
small :)
avg adult is 800-1200lbs
how has breed variety in the dairy industry changed over time?
there were many popular and prominent breeds in 1935, but moving toward 2012 and 2014, other breeds have dropped out as Holsteins dominated the industry
why are there so few dairy breeds compared to beef cattle breeds?
there are not as many benefits from crossbreeding in the dairy industry as in the beef industry
why is the dairy industry made up predominantly of Holstein and some Jersey milk today?
Holsteins have HIGH production, so you can get more milk with fewer cows
Jersey milk is good for cheese, butter, and ice cream
how does Dairy production work?
lots of small farms belong to Co-Ops, like Land O Lakes
how is milk quality measured?
in grades and classe
what is Grade A milk used for, and what are the SCC and bacteria levels?
fluid or manufacturing
SCC <100,000- likely not an infection
<1,000,000 bacteria/mL
what is Grade B milk used for and what are the SCC and bacteria levels?
manufacturing only, must be processed further
SCC >250,000
>1,000,000 bacteria/mL
what are the 4 milk classes?
I: fluid milk (50%)
II: soft products- yogurts, ice cream, sour cream (14%)
III: cheese (42%)
IV: butter (14%)
what are the two components of milk processing?
pasteurizing and homogenization
what is pasteurizing?
heating and cooling of milk to get rid of unwanted bacteria
4 –> 72 –> 4 degrees Celcius
what is homogenization?
the mechanical process of breaking down fat
what are the components of milk and where do they come from in the cow?
energy: Rumen (VFA’s) and Liver (glucose)
Fatty Acids and Amino Acids: intestinal wall
Water, vitamins, minerals: intestinal wall
lactose: liver
Fatty Acids: also come from body fat
protein: diet, microbes
what is the composition and percentages of milk?
water: 87%
lactose: 5%
fat: 3.5%
casein (protein): 2.8%
minerals: 0.7%
albumin (protein): 0.5%
list 10 animals that have mammary glands
- cows
- mares
- sows
- ewe
- dog
- cat
- deer
- elephant
- whale
- giraffe
list the 8 main structures of the mammary gland
- alveoli (alveolus)
- lobule
- lobe
- duct system
- gland cistern
- cricoid fold
- teat cistern
- streak canal
describe the alveoli
look like a cluster of grapes, lined with epithelial cells and surrounded by myoepithelial cells and blood capillaries
what do the epithelial cells lining the alveoli do?
they are milk making units, they synthesize milk and release it into the lumen for storage
what do the myoepithelial cells do?
contract to eject milk into the duct system
what do the blood capillaries surrounding the alveoli do?
transport hormones, like oxytocin, that stimulate the myoepithelial cells to contract
where does milk production take place?
epithelial cells of alveoli
what is milk made of?
lactose (galactose+glucose)
proteins (casein)
triglycerides
when does the duct system come into play?
during milking
in what order does milk travel through the duct system?
gland cistern to teat cistern to teat sphincter
what does post dip do to the teat sphincter and why?
adds a sealant barrier bc it stays open for a little while after milking
how is the udder separated?
into quarters by fine membranes
how is the left and right side of the udder separated?
by the central suspension ligament
why does the vascular system play a large role in milk production?
hormones!
is every animal’s lactation cycle the same?
no
when is Holstein peak lactation and how much is she producing?
at 40ish days at 75ish lbs
how long is a Holstein in milk?
around 305 days, and production drops off as time goes on
why is the calving interval important?
a cow must calve in to produce milk
list the cycle of events in the calving interval
parturition rebreeding gestation dry period parturition
what hormone plays a key role in milk let down?
oxytocin!
what stimuli can trigger the release of oxytocin?
sound of the milking machine, the sight of a calf, touching udder skin
how does oxytocin trigger milk let down?
acts on myoepithelial cells, which contract to force milk through the duct system and out
list the 4 parlor types?
- parallel/Bali style
- swingover
- herringbone
- rotary
how many cows can the parallel/bali style parlor milk and what are potential drawbacks?
50 cows/hr, but you have to wait until all cows are done milking and let them all out at once
how many cows can the swingover parlor milk and what are potential drawbacks?
60 cows/hr, but can be awkward with the tubing
how many cows can the herringbone parlor milk and what familiar dairy uses this style?
75 cows/hr, Berry dairy!
how many cows can the rotary parlor milk and what is it like?
250 cows/hr, like a carousel!
how many milking shifts do dairies usually do a day and how many hours between?
2-3
2 milking shifts: every 12 hrs, smaller dairies
3 milking shifts: every 8 hrs
what is mastitis?
an inflammation of the mammary glands
what happens with mastitis due to the quarters of the udder being separated?
it is possible to contain the mastitis to one quarter if no cross contamination occurs, and it is also possible to have different mastitis infections in separate quarters!
what is clinical mastitis?
symptomatic: inflammation, redness, milk discoloration and texture change, looks like a chunky strawberry milkshake
what is subclinical mastitis?
not symptomatic: SCC is high though
use CMT to diagnose, can send samples to a lab to identify the strain to treat more specifically
how does a CMT work?
milk into 4 trays and add a reagant
what are sire summaries?
they contain information about the sire that semen comes from, are a prediction of genetic merit with different traits listed to choose from, can even choose sexed semen
what are the 2 most common milk additives?
bST and rbST
bovine somatotropin and recombinant bovine somatotropin
naturally occurring and made in the lab
what is bST also called?
bGH, bovine growth hormone
what is bST?
a major regulator of milk production
how is bST given?
SQ injection because its polypeptide bonds would break down in the digestive system, that’s why it has no effect on humans
how many cows received bST in 2005 and what were the effects?
17.2% received, led to a 6-8% increase in feed intake and a 10-20% increase in milk production
how does bST work?
increases metabolic rate and lipolysis
what must also occur when bST or rbST is injected?
adequate additional nutrition must be provided, which leads to an increase in IGF-I, which increases milk production
what is IGF-I?
insulin growth factor, which increases milk production
how has social pressure affected the use of added bST?
no bST was used in 2017
is there any detectable difference in milk composition or influence on mastitis when adding bST?
no
list the 3 ways that the dairy industry has improved?
- Dairy Herd Improvement Association: record system, research utilized dairy animals bc record system
- limited number or traits selected for: milk production, led to more efficient cows
- Adaptation of technology
list 6 technology adaptations that have improved the dairy industry
- health programs
- nutrition
- facilities
- equipment
- AI**
- automated milking systems
