Thanks for the info on Taurine Michelle
It's probably way off the mark Sue but when Purdey had lungworm, initial test pointed to heart problems as her heart was enlarged. She also had a high temperature due to pneumonia. I'm sure your vets know what they are doing but just wanted to say, as Purdeys condition was misdiognosed for over 8 months.
Praying they find the cause of Daisy's illness & can make her better soon. Hope she has a comfortable night & send you both caring 
's
thinking of you & please let us know how she is doing 
Lindsey ...thanks for that
, have just googled and Drontal Plus does'nt cover Lungworm
We have lots of slugs and snails in the garden and also foxes around so definately worth mentioning to vet, will do that.
Thank you all sooo much for your kind support. Daisy has been ok overnight and her temperature ok since 1am, but heart rate still a bit high. She has not yet eaten or drunk ..which is unusual, but is probably because she is away from home. The vet wants to keep her today so she will go to my vets for monitoring and back to him tonight so that he can check on her when he is back on duty. If she is ok he will let her come home and he will be on duty overnight in case I need him. She will then need an ultrasound next week to see exactly what the heart condition is. Will let you know how she is later x
