I've had only a few within three years that's developed a tilting head and they were all females. I've no clue as to what caused it but I allowed one to live, instead of feeding it off, as an experiment and it seemed to have lived a healthy, normal life other than the head tilt.
Thinking in human terms, sometimes when I get a respiratory infection or something of that nature my inner ears get clogged up as well. Could be hereditary, where an RI may not cause head tilt in one rat but will in another if the genetics allow it.
Could it be possible to eliminate it by feeding off the infected & their offspring? I don't know. Maybe, maybe not.
Take care!
HH
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Due to political correctness run amuck,
this ol' hillbilly is now referred to as an:
Appalachian American