Poorly 19month old pup

sorry this is long but needed to give full context! I have a 10 month old puppy that started with diarreah 15th July eve and has been either loose or watery since. Sunday 16th July stopped eating. Offered normal food on the 17th July didn’t eat. 18th July ate normally on the evening. Didn’t eat again on the 19th, offered wet food on the 20th and within an hour brought it all back up. Took to the vets on the 20th given promax and anti sickness injection and give bits of chicken or fish 21st ate chicken - kept it down, Diarreah persists 22nd vomited again in the morning and very lethargic, took back to the vets, extended promax - took bloods (all ok) 22nd sat afternoon and Sunday he seemed to pick up - ate a bit of kibble Sunday morning and had a soft but formed poo. mon 24th would only eat kibble with wet food in the afternoon Tuesday 25th watery diarreah and back to not eating anything other than chicken Wednesday - sleepy / only eating chicken Thursday (today) sleepy, won’t eat kibble, very small amounts of poo that are clay like from the promax - Temp is 39.08 - it has been 38.2 ish till today! vet is saying to collect a 3 day fecal sample to test. He is drinking, mm refill is fine, definitely loosing weight but not really playing and sleeping all day. this is a puppy who would be jumping round and generally be hard work morning till bed time with so much energy, usually would need a morning walk and a good long walk in the evening plus playtime or he would be bouncing round the house on the evening! now he gets up, goes to the toilet and lies down and sleeps most of the day, he will walk but tires quickly, same with playing - tires very quickly I feel like the vet thinks there’s nothing wrong as clinically apart from Diarreah he is ok, thinks a bug that will pass but I’m not convinced?  

Title is meant to say 10 month old

Hello - does your vet know about the recent lethargy? - as they may want to check your dog again.   Of course there are multiple possibile causes of diarrhoea of varying severity, but new or worsening symptoms should always be reported straight back to the vet in charge of the case or their emergency out of hours team.  At some stage, ongoing diarrhoea will cause dehydration and if this may be occuring, it could become an emergency.  Diarrhoea is a symptoms and treatment can often be symptomatic eg bland diet.  However if the symptoms worsen to include dehydration, more vigorous symptomatic treatment - or even further investigation of the cause - may become necessary.

Sending love and best wishes to your pup at this time.

Hi, yes they do. I called before I wrote this out. He ended up in for the day on fluids on Friday but no answers yet. they also tested for Addisons (but unlikely as bloods were fine) there’s plan to scope depending on Addisons results. He is better after fluids and metaclop but not 100% stools still soft, formed initially then cow pat like but not water. dropping off fecal samples tomorrow, my gut feeling is giardia/ some sort of gut infection :(

All the best with this case and please do let us know how your baby's getting on.