[SteveHants]

I view EBV's with a good deal of scepticism - thought I'd try a ram with good all round scores for the first time this year and his lambs have been no better, or worse, than those of any other ram I've picked by eye off farm, except he's thrown 55% ram lambs in the Southdowns and 90% in the Badger Face Xs, instead of the usual 45% ish!  If I select a ram lamb to grow on for breeding it's always a twin that's been healthy, vigorous and has excellent conformation.  Since I only keep ewes that are also that way and lamb without assistance and are excellent, milky and long-lived mothers, I have to assume that these traits, generation on generation, will become increasingly fixed in the flock.

Of course - they are not a magic bullet, they just give an insight on how an animal might perform and give you more to go on that judging by eye could. Things like muscle depth become more important if you are selling deadweight etc - The buying off-farm is very important in ram selection too. The 'other' important (some might say most important) use of EBVs is improving your own maternal flock. It does seem to be said wherever you read it though that those breeds who do performance record have seen rapid genetic gains - For the ultimate example of this, talk to a Kiwi involved in Romneys etc.

[landroverroy]

So for a terminal sire the animal should be a good size and shape, and I'm sorry Steve but a poorly finished animal that has not had sufficient food to show its potential is not going to impress anybody.

Yes, but this food should consist of the same food that I am going to feed its progeny - ie grass. This is why I buy off-farm.___ End quote. . .
 
 
With all due respect, if you get fat on biscuits that does not stop you also getting fat on chips, steak, rice or anything else you happen to eat. Your body doesn't then become programmed to only fatten on biscuits! The idea of feeding up a show ram is to indicate the potential of how much weight and shape he will achieve without having to wait for the same end result off grass alone.
The fact the sire has been fattened mainly on concentrates in order to show off his potential is not carried over in his genes to his offspring. The resultant lambs will still fatten on grass or whatever combination of fibre and concentrates you choose. Do not mix breeding with feeding. 

[feldar]

I think this subject may rumble on for some time!
But as correctly said by others the phenotype, what the ram looks like will not always indicate his genetics and progeny. which is why so much work has gone into EBVs and genetic performance.
We have completely turned the Hampshires around from being a fat overstuffed waddling breed into a terminal sire of impact with fast finishing lambs with good food conversion.
Talking of food conversion. I feel this is the most important aspect if your lambs don't have the genetics behind them to convert the food they are given you are on an uphill battle right from the start.
 
Showing from my point of view is more to show other breeders what i can produce. yes they are fed more, a skeleton will win me no prizes but niether will a fatty, it is a balance.
My word of warning is remember that a show winner may just be a one off.
I know a ram that has won a lot this year already but if you went to visit the flock the rest of the sheep don't reflect this ram, they are very inconsistant. A commercial man is looking for consistancy not the occasional fast finishing lamb, that's why it's figures are important, they should reflect his abilities accross the whole flock. It is a science and a question of picking the right ram to match what type of ewes you have, with a bit of good luck thrown in as well