Friend, when we see blood in the stool it is a sign of inflammation in the colon (large intestines). The diarrhea is a consequence of the inflammation. The sounds you are hearing are common when the intestines are over active.
Bloody diarrhea can be caused by many different conditions. It will be difficult for me to determine the exact underlying cause without a hands on examination and some testing. But, common causes are: Dietary indiscretion, ingestion of a foreign body, infections, or even part of a systemic disease to name a few causes. As far as the cough this can be a completely different problem a very common cause is a respiratory infection. Other possible causes are: A collapsing trachea, underlying heart disease, etc.
In this case, I would recommend a hands on examination with family veterinarian to determine the exact underlying cause for the bloody stool. And, to listen to his heart and lungs. He may need oral antibiotics. In the meantime this is what you can do:
1- Do not give things like Pepto Bismol or imodium. You can start him on Robitussin DM (cough) 1/2 teaspoon every 6-8 hours. You can buy Robitussin over the counter in any pharmacy.
2- No food or water for 8-10 hours, need to give his gastrointestinal tract time to rest. Then, offer small amount of water followed by a diet of rice (75%) and boiled boneless chicken or ground beef (25%) until the stool is back to normal then wean him back into his regular diet.
3- Supplement with a probiotic (fortiflora), these are friendly bacteria that help with regularity. You can buy this over the counter in any pet store.
4- Follow up with your family veterinarian for a hands on examination.
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