I seldom see chickens with scissor beaks and messed up feet at hatch. When I do it comes in spurts with incubator hatched chicks. More than once I have had this where the same mating gives quality chicks time and again then one batch is 3 funky chicks out 12 that normally dispatched on the spot and putting the parents at risk of being culled themselves. A batch hatch at school gave three cretins. One American Dominique pullet has a really crappy looking beak, but she is in good weight and just came into lay. She was allowed to stay owing to interest of students. I am going to hatch chicks from her line-bred back to her father to see what pops out.