What's wrong with the grass and birds pulling thin

The grassable sparrows are usually because they eat unclean foods, and they may also be cold.For foods that are not clean, they usually need to replace the feed appropriately. Check it on a regular basis to see if there is a deterioration.For the dilutes caused by cooling, you need to keep warm to prevent the birds from being blown by the wind. At the same time, let it be exposed after taking a bath so that the water on the body can volatilize as soon as possible.