Here are a few of the most easy to spot signs that a pigeon may be unwell.
‘Going light’ is commonly used to describe progressive weight loss in pigeons
Essentially, the bird continues to lose weight, in some instances they will retain fairly tight feathers and white wattles giving the outward appearance of good health. In other cases the bird will ‘blow’ it’s feathers, and tend to huddle or hunch it’s back. Also, at times the droppings will become sloppy and tinted green with bile as you’d see with diarrhoea.
Going light is a general symptom for a range of ailments and diseases but primarily coccidiosis, polyneuritis, and bacterial infections such as E. Coli.
Loss of plumage tightness
The feathers stick out away from the body as the pigeon tries to cool its temperature resulting from fever. It lifts the feathers to allow cool air onto the skin.Feathers of a sick pigeon are dry and coarse, appearing to be brittle to the touch, whereas a healthy pigeon has satin smooth, almost ‘greasy’ feathers.
A poor posture, i.e. hunching with shoulders up and head drooping may be an indication of bad health.
Wishy-washy, dull, and vacant eyes often accompanied by the irregular movement of the nictitating membrane, which, instead of flicking across the eye with speed, crawls across it, as if tired and without energy.
Droppings are one of the best indicators of a pigeon’s health. If you suspect a pigeon is unhealthy it is of paramount importance that you took a closer look at the droppings.
If you witness a sudden change in the form or colour of the droppings there is usually something wrong, especially if you haven’t altered the feed or given them any kind of medication.A good dropping is usually perfectly formed, quite small, and will have a little white cap and a down feather on it.
This is a great article on dropping interpretation.