I have several orpingtons that at 9 weeks, still have no tail feathers, they are fully feathered otherwise. I've never had orps without tails and these are from eggs I bought online. could this be a male trait? no one is pulling out the feathers, they just never have had them. they have, or carry lavender and some carry brown genes but not all. editted to add: slow feathering gene- could this lack of a tail be the slow feathering gene and be an indicator of male sex? some are showing they are obviously cockerals and some I don't think are developed enough to say which sex.