Darcelina,
A couple of things..
1. as far as the heifers go, you cant ever guess a weight based on comparing it to other animal, I have weighed hundreds of steers/heifers in that range and there is always some in every group that you say hmm, cant believe he weighed xxx he looks bigger/smaller than his brother.. muscle, fill, etc just make too much of a difference.
2. The steer- he probably didnt lose any weight in 12 days but the trip to/from the fair could have knocked him off schedule. any kind of stress like that could have an effect. We have had steers that have come back from a show and gain 7 lbs in a week and some that gain 50 lbs..
3. How far of a haul did they make to the processing facility? Shrink could be a difference maker here.
4. Did the processor weigh the heifer/steer with the liver in or out? That is 15lbs makes about 1% difference on the steer.
5. Could the scales at the fair be off? I would bet the processor scales are certified but maybe not.
We haul our freezer beefs 90 miles one way to the processor and usually end up with dressing percentages in the 55% - 62% range pretty regularly heifers will normally be 55-58% steers are sometimes 55 but normally 57-62%.
The other thing if you have to question your processor you must have some facts to back it up.. or find one you trust..