Questions about this hen herself
Start with the bird in your hands. Ask whether her age and breed make a pause in laying expected: many hens lay strongly for their first seasons and then taper, and some breeds were never bred to lay through the year. Ask the vet to judge her body condition, whether she feels too thin across the breastbone or heavy with internal fat, both of which stop laying by different routes. Ask about the physical checks: whether her vent looks like a laying bird's, whether the crop empties properly overnight, and whether the abdomen feels normal, because a hen can stop laying for reasons ranging from a retained egg to changes you can only find by handling her. Ask, too, whether the pause fits a moult, and how to tell the difference between a hen resting and a hen in trouble.
Questions about parasites and hidden illness
A hen can be quietly unwell for a long time before she looks ill, and stopping laying is often the first sign she offers. Ask whether worms or external parasites such as red mite could be draining her, and what evidence the vet would want, a droppings sample, a look at the coop after dark, before treating. Ask which illnesses commonly present this way in backyard flocks and which of them matter for the rest of your birds, because that answer decides whether this is one hen's problem or a flock problem. If the vet finds something, ask what it means for eggs already collected, for the other hens, and for any plans to add birds.
Questions about the flock's pattern
Bring the flock's evidence with you and ask the vet to read it. If every hen has slowed together, the cause usually sits in shared circumstances; if one hen has stopped while her sisters lay on, the cause is more likely inside that bird. Ask what the pattern suggests about laying cycles, about older hens masking a general drop, and about whether a recent stress, a predator scare, a new bird, a moved coop, could explain a group pause. Questions framed on the pattern save the vet from guessing and save you from treating a healthy flock for one bird's problem.
Questions about feed, light and housing to review
Some of the most useful questions send you home to your own management. Ask whether the current feed gives laying hens what egg production demands, particularly protein and calcium, and whether treats, scraps or free-ranging on poor ground could be diluting it. Ask about daylight: hens respond to day length, and a drop into shorter days switches many birds off lay without anything being wrong. Ask about water, because a drinker problem stops laying faster than almost anything, and about the nest boxes and coop, since a hen being bullied away from feed or frightened at night rarely lays well. Write the answers down, because the changes are usually yours to make.
Questions about what happens next
Finish with the forward-looking questions. Ask what you should monitor over the next few weeks, which eggs, droppings or behaviours to note, and what change means come back now rather than wait: straining, a swollen abdomen, discharge, weight loss, or other hens developing the same picture. Ask when laying should reasonably resume if the cause is seasonal or a moult, so you are not worrying on the wrong timescale. Arriving with a few weeks of simple records, kept in KinsLe's Pet Passport with the flock's health notes, means the vet answers from your hens' real history instead of from a guess about a typical flock.