Time to play ! : the answer
To review the original article and video, click HERE.
Thanks for sharing your thoughts on Facebook or here. We love it :-). And congratulations to those that had it right! The cat indeed ingested a long elastic band that served to hold the bag on the bottom of its litter box. These rads were taken after the ultrasound was done. The mineral opacity was probably attributed to the coating of the elastic band. The other curvilinear mineral opacity on the ventral aspect of the abdomen is due to residual ultrasound gel.
The cat went to surgery and here is the picture of what was removed from the stomach and from the duodenum! The cat is doing fine today. Thanks to the elasticity of his stomach ;-).