Egg size?

They are called pullet eggs and are smaller than how her eggs will be in just a couple-three months.

 

Yeah they get bigger! It usually doesn't take long.

 

I have two ee's that lay green eggs. They are about 9 months old now and both of them started much smaller than they are now, just be aware that ee,s may never lay a large egg some will stay at a large medium. I have one of those and the other lays a large egg, but either way they will eat just fine.

 

Question
Re. unexplained loss of Buff Orpington
My mixed chicken flock, hereto previously healthy, two weeks ago started "picking." Four out of 24 birds show signs of bare bottom spots. I have treated w/ a mixture of Desitin and GoldBond Med. powder, sometimes mixed w/ olive oil. One of the birds is a rooster. They continue w/ good appetite and drinking water.
New flock
New coop, 8' by 8', lino floor, good ventilaton, hanging water and food inside during winter, some food/water hanging during summer
Sliding door and ramp for coop access
Enclosed yard, 12-inch deep w/ clean sand, 25' by 35', fenced and wired perimeter and top.
Yesterday morning I found a dead Buff in a floor-level nest, head hanging over side of box. No exterior damage, no picking evident on this hen.
Constant temp in coop 30F, 4 feet above floor. All roosts well spaced 4' or more above floor.
Two months ago, I started a 'treat' program w/ some cracked corn on ground outside in the mornings; regular feed and water are always in coop only. In summer, water also hanging in fenced yard. For winter, water is set on heating pan (not hanging) in coop.
Possibilities:
Hen was stepped on inadertently by other hen in a low next box?
Disease made her weak to changing temperatures?
Coccidiosis?