A bird with good resistance may not show symptoms or only mild . I have seen birds that had mycoplasma have a very light rattle when breathing . Others have runny eyes and swelling of the facial sinus cavities when first infected .You should do BBS nails to match your darling little chickies.
Oh gosh those are darling!
Woooo, now I understand the (+) following certain symbols, thank you! Is a symbols capitalization have anything to do with its dominance? Lower case meas recessive and Capitol mean dominant right? does that mean that if it contains an upp and lower case, like Bl for blue that it is incomplete dominant?
Does this include birds that get sick after being seriously stressed? Can't birds still be carriers without ever showing symptoms or do they always show symptoms when they become infected for the first time?
Think of carriers like chicken pox in people . When you get it as a child and recover your body has suppressed the virus . It hides in ganglion nerve centers and goes dormant . It is called shingles when it reappears later in life . Often in older people who have weakened immune systems . Stress can also weaken your immune system . So you are a carrier but the virus is dormant . You are infectious when it reappears .
I noticed years ago that birds that recovered from coryza would often get it again in the winter ( stressed by very cold temps ) . They would then infect other birds .