Thank you for your patience. Your boy's symptoms are definitely very concerning - particularly given his age and the fact he has only had his first vaccintion. We have to consider everything from simple colitis (from the food change and deworming tablet), to an infectious haemorrhagic gastroenteritis due to something like Parvo virus, or a bacterial issue. Because of his age and susceptibility to parvo virus, we are safest to keep parvo virus in the front of our minds here. While some soft stool with a small amount of blood can be due to a sudden diet change or deworming medication causing inflammation of the colon (colitis), generally we see that the stool is pretty normal, with a little more mucus and blood on it, rather than the entire stool being completely liquid with blood.
The key worry here is that your boy will become dehydrated quite quickly with this type of liquid diarrhea, and the amount of blood being lost could also quickly cause an anaemia. If you can get him seen this morning by a local vet or after hours vet, I would definitely recommend that. For now, make sure he has plenty of water available and continue to offer him the food you changed him over to on Friday (assuming it is a good quality puppy food). Please keep a close eye on his mucus membranes, capillary refill time and respiratory rate today as follows:
Mucus membranes - flip his lip and look at the color of his gums. They should maintain a nice salmon pink color. Get him to the vet or emergency vet today if they appear white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on his gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the vet.
Respiratory Rate - if he is continuously panting throughout the night, this is a sign of shock and or pain and a signal for a trip to the vet or emergency vet.
Because he is so young and has such bad, liquid and bloody diarrhea, we really have to be worried about both parvo virus and other infectious causes of haemorrhagic diarrhoea. If you can get him seen this morning, that would be the best way forward. As he is so small, it is quite possible that he is becoming dehydrated, and possibly even anemic within the short space of time that these symptoms started. If there has only been very small amounts of blood on top of 'normal' looking poo, then this is more likely to be 'colitis' due to the deworming meds and change in diet, however it is better to play it safe in this situation given his age and history. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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