Hi, sorry I am only seeing your recent posts. How often to worm depends on your climate and whether or not you have been able to get a fecal float on the droppings to know what, if any, type of worms they have. Many who live in warm tropical climates worm every 2 months, while some worm twice a year. Those who live in dry cool environments may only worm once a year. Some people never worm their chickens, but it is good to check a fecal float to see if they have worms. Those who cannot get a fecal float by a vet may go ahead and worm for any possible worms. Their is a kit available on Amazon to check for worms:
https://www.amazon.com/Reptiles-Rabbits-Turtles-Collect-Sample/dp/B000J5SOZ4
Hens can lay for many years, although some will suffer from reproductive disorders. Infectious bronchitis in the flock can increase reproductive problems. Coccidisosis and respiratory diseases may affect future laying, so keeping your flock healthy is important. I have had hens stop laying at 2 years, and I have hens laying who are 7. Breeds matter, but health is more important.
https://www.amazon.com/Reptiles-Rabbits-Turtles-Collect-Sample/dp/B000J5SOZ4
Hens can lay for many years, although some will suffer from reproductive disorders. Infectious bronchitis in the flock can increase reproductive problems. Coccidisosis and respiratory diseases may affect future laying, so keeping your flock healthy is important. I have had hens stop laying at 2 years, and I have hens laying who are 7. Breeds matter, but health is more important.