Welcome To BYCAny update on this post? I have a hen with a solid mass in her abdomen. She frequently passes little white lumps in her poo. They do look different that a lash egg as the lash eggs I've seen tend to be flesh coloured. The vet thinks she should be put down and wouldn't administer antibiotics for her. Gor what reason would a hen body expel something like this? Does this signify that there is infection going on? I can't bring myself yo have the hen put down without knowing I've done all I can. Should I try get a dose of antibiotic for her?
This thread is from 2021 so unlikely to get an update from the OP.
In your photos, it does look like Lash Material. Salpingitis is inflammation of the Oviduct. You can try treating with an antibiotic to see if the hen improves for a period of time. Most folks administer Amoxicillin or Baytril.
https://the-chicken-chick.com/salpingitis-lash-eggs-in-backyard/
https://the-chicken-chick.com/causes-of-lash-eggs-salpingitis-by/