Welcome to the board.
Just one correction, sheep are in 'flocks' not herds.
Cows are in 'herds'
Which leads to an ad that we have been seeing lately where a townie says to the farmer..
"nice flock of cows"
The farmer replies "Herd of cows"
The offended townie retorts "Sure I've heard of cows, have you heard of chickens?"
[Edited on 8-6-2003 by Netchicken]