Hello,
Really it depends on what caused the diarrhea in the river water. If it is a bacteria you run a chance of an infection or the dogs body might be able to fight it off. No way to tell until the dog has gone on for a few days and then the dog might be in real trouble.
Pumpkin is a great do all vacatable. It helps dogs with diarrhea and constipation, but does not take care of parasites.
The other problem may be Giardia is a protozoa, or a small, single-celled creature that infests the digestive systems of dogs. It concentrates in the intestines, sticking to the walls and floating around in the goop. In most dogs infested with giardia, it causes a disease called Giardiasis. Some dogs, however, don't show any negative effects at all from the infestation.
In dogs that have symptoms, they will show general digestive problems. These include diarrhea, blood in the dog's stool, weight loss and lack of appetite, and generally seeming like the dog is doing poorly. The feces of the dog can also start to look and smell abnormal. It may look white or light colored.
It is transmitted between animals that already have it. It can be transmitted either because animals are living in very close quarters with each other or through food and water. Contaminated water is the biggest cause - often dogs will get the parasites by drinking standing water that has been infested with them. If you take your dog hiking or wandering around near any rivers, creeks, or lakes, it is a bad idea to let them wander off, and you should always bring clean water with you for the dog to drink.
In the home environment, giardia leave the animals through their feces, so your dog could get it by using the restroom in a park, yard, or other area where a contaminated dog has been. Dogs can easily get it on their paws and then ingest it. Dogs in kennels can be at risk if one of the dogs has it, as it is very easy to transmit in that environment. Likewise, breeders face a big risk of an outbreak among their animals.
The drugs used to treat it in dogs include Metronidazole, Quinacrine, and Furazolidone. Your vet will decide on one and will also do several fecal tests to make sure that this is the cause of the dog's symptoms - many other diseases can cause the same vague symptoms and you need to be sure. Generally dogs recover well from it, but puppies are more at risk because a puppy does not have a well-developed immune system. Similarly, dogs that have had other medical issues that result in suppressed immune systems are more at risk. The biggest concern is dehydration as a consequence of the diarrhea, so you need to make sure your dog is drinking plenty of water. If the dog does not seem to be drinking, the vet may want to put them on an IV to keep its fluid levels high.
For more info on Western diagnosis see
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