Hi, I'm Dr Steve
From your description of the symptoms, one possibility that is consistent with their symptoms is TGE.
TGEis Transmissable Gastroenteritis and is a viral infection that can affect sows as well as piglets. It causes diarrhea and vomiting. Since it is a virus , there is no good medicine to kill the TGE virus. In most cases when a pig ets TGE, it also has additional bactrial problems like E.coli or Salmonella. These can be treated with antibiotics.
Unfortunately in my experience pen-strep is not very effective against the bacteria that cause diarrhea. I have had better results with Nu-Flor, and oral gentamycin. These are licensed for use in pigs in the US. I am not sure if their status in the UK. You will have to talk to a vet in your area to findi out if these are available. In the US they are only available from a vet and this may also be the case in the UK.
What happens with TGE is that the pigs bcome affected and they vomit and have diarrhea . THis causes dehydration andelectrolyte loss. The treatment is aimed at controlling the bacteria that I mentioned. THis leaves the TGE virus to be controlled by the pig's immune system. There is no effective vaccine for this so the pig has to let it run its course, like the human cold.
The other thign that you can do to help the pig get through this is to put an electrolyte solution in the water to prevent dehydration and replace electolyte loss. There are many electrolyte solutions availabel everywhere and they are typcally all effective.
Usually the sow is able to handle the stress of this disease since she is more mature, so I typically dont treat the sow, I just let the disease run its course. Unfortunately some pigs have a case that is too severe and they don't make it. The only thign to do is try and hope.
There are some other disease that can cause diarrhea in pigs like PRRS ( porcine respiratry and reproductive syndrome), Circovirus, Rota virus, to name a few. Since these are all viruses the management is the same as for TGE. The reason I am mentioning these is that if it is one of these other virues, they can be more severe and can cause sow death and often are more damaging to piglets. One good option would be to discuss this specific case with your vet. He may be able to tell you if there is one of these virus infections going around your area and can offer some diagnostic testing to help determine exactly which if these is the problem.
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