Nicolle, I missed your 2nd post before posting myself.  From what I read at the time, some horses with anaplasmosis develop a fever which doesn’t last long.  The fever was the most obvious sign with our pony.  Those ticks carry all sorts of nasty diseases.  When I looked up which ticks carry Lyme, I saw that the Ixodes pacificus is one of them.  Here, it is Ixodes scapularis which seems to carry all these.  The same drug will treat all these things so best to just get started to see if that helps.  My daughter seemed to recall that the Ixodes pacificus isn’t as likely to be a Lyme carrier as an anaplasmosis carrier.  We are literally infested with ticks here and my husband was very sick in the hospital with Lyme just as Covid began to fill the hospital ERs so we are highly tuned into avoiding them as best we can.
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