If a Guinea Pig is a good feeder and still does not grow, if he looks unhealthy and his coat is not glossy he may have worms. Give a half teaspoonful of any kind of worm medicine such as children use. Feed lightly and not at all until the medicine has taken effect.
Going Light.
Sometimes in spite of all you can do a Guinea Pig goes light. If the treatment for worms has no effect it may be tuberculosis. Separate at once from the others. Give special diet of milk and bread or bran and oats. If it does not get better destroy it as it does not pay to have such stock around.
Colds, Pneumonia.
When they have pneumonia there is usually no help for them. Cold, damp and drafty quarters are usually the cause. About the only thing to do is to move them to warmer quarters, give warm milk and a few drops of any good cold remedy that you may have in the house. As an ounce of prevention is worth a pound of cure you should use every care to see that they do not catch cold.
Lice.
Use any good insect powder or any poultry lice killer. Clean out the hutches or pens and disinfect with any good disinfectant. They are not often bothered if kept in good condition.
Wounds.
Males sometimes hurt each other in fights. Cleanse the wound with warm water, remove the hair around it with sharp scissors and apply any good healing salve.