October 29, 2009

The Evolution of the Dairy Cow


Once again, cartoons have confused science for me. In the cartoon world, dairy cows need to be milked constantly or else they'll explode. But, this implies that before their domestication by humans, dairy cows could not have existed. So, do dairy cows only keep producing milk because machines keep suckling it, so their bodies think that they're still nursing?

10 comments:

Meghan said...

I think it's the same as with humans - supply and demand. If no one milked the cows then they would just stop producing milk. Plus the cows of today are probably given extra hormones to up production...

Anonymous said...

think of wet nurses

Eric Olsen said...

i'm not aware of the physics there, how does that work? if you never stop nursing, you'll never stop?

Anonymous said...

I am reminded of a quote from Malcolm in the Middle: "Women are the cows of people!"

Brilliant. But just offensive enough for me to log this under anonymous.

:)

Meghan said...

Now I'm wondering who the last anon poster is! haha

Yes Eric, if a woman keeps nursing she will keep producing milk. I just spoke with my MD friend and he gave me a detailed explanation: the sucking action of the baby (excuse that if it's too graphic) sends a signal to 1) increase the release of oxytocin, which is a potent vaso-constrictor. This serves to eject the milk. and 2) keep levels of prolactin high; this hormone makes the alveolar cells in the mammary gland produce milk. The key is the sucking (whether by a baby or by a machine, i.e. breast pump). This reflex needs to be done about every 4 hours or the process will stop. That's why women I work with pump every 4 hours during the day and dump it out. OK - TMI right??? :)

Eric Olsen said...

wasted breast milk?? i think i just figured out a new eBay Business.

but, seriously, why can't they pump into a bottle and bring it home?

and even if the kid's sleeping through the night by 9 months, but you're still breastfeeding, you have to wake up every 4 hours?

Meghan said...

yeah great business plan :)

I think the problem is they don't want to have to refrigerate the milk all day and remember to bring it home. Plus some of us might freak out if there was breast milk next to our lunches in the shared mini-fridges :) I doubt they have to get up in the middle of the night, probably once before bed and first thing in the morning is fine, but I don't know for sure. The 4 hour thing was told to my a doctor so it's probably an estimate based on averages.

Eric Olsen said...

Tired of sneaking into the bathroom at work to pump, and grossing out your co-workers?

Well, those days are over!

Introducing, the Uddervest! A comfortable, and fashionable vest with built in pumps to let you milk and work at the same time!

Becky Johnson said...

Oh Eric, just wait 'til you have kids, then you'll learn a lot about this whole milk production thing.

Eric Olsen said...

i'm already planning on saving a gallon a week, Becky.