How often are you checking the tightness? I emailed the manufacturer for recommendations on how often to check because he's still so young, but they haven't responded.
Are you putting the collar at the base of his neck?
At what age would it be safe to use? My welsummer is only 11 weeks, but has been crowing for a month. Can I use the collar now, or do I risk cutting off airflow because he's still growing? If I can use it now, would I adjust it weekly as he grows? I'd really love to keep him but, he's crowing...