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Summary to the cow digestion?

I don't really follow how they explain it in the book, can someone summaries it for me or is there a web site wait a summary, if so could i have the address? Thanks.

Reply 1

Pumpkinfoodle

go search it on the web, its really easy. if we all just type a load of text its just gonna be so monotonous :smile:

Reply 2

Ramaya

I don't know if this will help but i wrote up these notes on my website:

http://www.freewebs.com/biologynotes/nutrition.htm

its towards the middle of the page.

Reply 3

DivineComedy

Ok here goes, bit of revision for me too...

Don't know if you wanted bit about teeth but you know lower incisirs point forward and crop grass against 'horny pad', large area of no teeth or 'diastemma' for good tongue action to pull on grass, 'open rooted' teeth, so continually growing as continually been worn away, and jaw muscles allow side to side action for better grass chewing.

Carbohydrates

Cow needs to digest tough polysaccharide cellulose so lots of amylase in saliva, swallows down to rumen & reticulum where can be regurgitated to 'chew the cud.' A community of anaerobic bacteria live in these two stomachs and produce the enzymes to break down cellulose ---> cellobiose ---> glucose which is then transfered to fatty acids and absorbed (main respiratory substrate for cows).

Proteins

Bit more involved, cow doesn't get much protein from diet so has its own 'internal nitrogen cycle!' The cows saliva (about 100dm3 a day!!!) has loads of urea in it. This gets swallowed into rumen and reticulum again. This urea has loads of nitrogen in it so the little microorganisms use it to make their own protein. The cow takes advantage of this and digests these guys in the abomasum stomach to amino acids. These amino acids are used to make cow proteins and left over ones are deaminated in the liver to make......UREA! which makes its may to the cows saliva, nice little circuit.

Hope this helps! Let me know if you understand it, or whether I've made you even more confused!...

Ali

xxxx

Reply 4

MJ_23