@TropicalChickies has given you thoroughly good advice.
My take on this hen is that she's likely been suffering from shock since the dog attack, and she may have an internal injury, as well. All else has been led by this.
Bugs show up when the chicken's immune system is being tasked, but parasites aren't the immediate issue. Shock is. Always treat for shock first thing after an attack. Give her one teaspoon of sugar in one cup of tepid water and add a pinch of salt and baking soda.
Give the water as her only water for the next 24 hours. You should see some improvement in her behavior. But if this has triggered Marek's symptoms, the die is cast.
My take on this hen is that she's likely been suffering from shock since the dog attack, and she may have an internal injury, as well. All else has been led by this.
Bugs show up when the chicken's immune system is being tasked, but parasites aren't the immediate issue. Shock is. Always treat for shock first thing after an attack. Give her one teaspoon of sugar in one cup of tepid water and add a pinch of salt and baking soda.
Give the water as her only water for the next 24 hours. You should see some improvement in her behavior. But if this has triggered Marek's symptoms, the die is cast.