Last week, my neighbour had the environmental health people round to investigate  rats in her garden.  The EH officer was very nice and warned me to keep my dogs away from the connected fence area where the rat hole was.
I've made sure the dogs were never left unattended in the garden and kept them away from that side of it.
This morning I found a dead rat on the lawn. It was so early in the morning and still dark. I'd let them off the lead when we came back to the garden and was picking up some poo when I realised that one of them was sniffing something. On going over to check, I realised it was a rat.
I've been to the vet and the dog's been given the antidote to the poison used. The EH inspector has been back and picked up the body. He also went round my garden and its clear of any sign of rats - apart from what he thinks is a 'trail' from the neighbour on one side to the neighbour on my other side. One feeds the birds a lot (twice a day, lots of bread and stuff) and he says the dogs stop the rats living in my garden.
He also assured me the poison won't affect the dogs at all unless they are eating lots of dead rats.
What I'd like to know from the experience of people here is:

1 Does large of amounts of vitimin K have any adverse affects?
2 What happens to the fleas that rats carry when they get poisoned - will the fleas get poisoned too? (this is just me being curious)?
3 If there has been one rat, will there be more? Will I have to permanantly check for rat bodies every day?
4) I know rats carry diseases and dogs are vacinated against them, but 2 of my dogs are rescues - the oldest is 13 and has not had any vaccinations since being a pup. I've only had him a few months - should I have him vaccinated now? Initially my vet wasn't keen as he was so old, but if I have rats about, is it now a better idea?

The EH inspector also said he understood why people feed birds, but wishes that they'd feed them wild bird seed and not bread, as its the bread that encourages the rats. And generally, the birds don't need it till winter, so all that they are doing is feeding pigeons, magpies, seagulls and rooks.
Also - if you put out peanuts for birds, its got large amounts of vit. K in it, so its possible that rats will survive a poison attempt due to eating the birds peanuts.
Now I have to gently tell my neighbours that they are encouraging rats, and I know how upset they will be!

I can't answer a lot of your questions, but a couple of points:

What kills the rats is internal bleeding, as the poison stops the blood from clotting and thins it -it is in fact the same drug (Warfarin) given to people that need to have their blood thinned due to heart attacks, blood clots, strokes etc -I've been on it myself. I doubt this would kill the fleas on the rats.

I don't really see the point about people should feed the birds seed instead, because it's quite common among peple who breed fancy rats to feed them on wild bird seed mixes?? So they will defintiely eat seed. It's definitely a problem hard to solve. :(

I hope somebody else can help with your questions.

Sorry I cant answer your questions either, but would just like to say re this line

>>and he says the dogs stop the rats living in my garden.

Not true. I had a german shepherd and wolfhound X which pretty much used to live in my back garden access all areas. Upon finding rat poo one day in the dogs stone kennel area, I did a very thorough search of the garden and found a whole nest of rats living inside a compost heap at the bottom of my garden. :(

I was in a similar situation a few years ago.  Dogs don't stop rats - I had 4 dogs!!  And feeding seed only wouldn't stop them either.  The poison is coated seed - that's exactly what the rats go for or they'd coat bread!

I had the problem because neighbours both sides fed the birds and kept compost heaps.

But I was told by the Council Ratman that animals have to eat their body weight.  I was still concerned because he used a big tub of the stuff every time that he came, every week for 18 months.  I thought that the neighbours would start talking, and not about the rats! ;)  I had really lovely neighbours but they refused to stop feeding the poor birds and of course wanted to be environmentally friendly with their compost heaps. 

I hated putting poison down.  I don't like to kill anything but also wasn't happy watching the rats using my garden as a picnic area.  I moved!

Hi, the stuff poisioning the rats is warfarin and  Vit Kis given to reverse it. Its unlikely that your dogs would have got enough warfarin from a rat corpse to cause them any harm but your vet has given them Vit K which reverses the effects of warfarin to be on the safe side. A single big dose of Vit K should not have any side effects.

Sorry to say but in my experience where you've had one rat you'll probably have more :(

Rats carry leptospirosis. The anti-viral dog vaccines against parvo etc almost certainly last longer than a year and may (no one really knows) last life long but leptospirosis is caused by a bacteria and the protection given by the vaccine lasts less than one year. So in ideal circumstances it should be given every year in the spring when the risk of leptospirosis starts to rise. Of all the vaccines given to a dog the lepto vaccine has the highest risk of causing adverse side-effects but the proportion of dogs having problems with it is still low. If you have any stagnant water in your garden that the dogs can drink after the rats have urinated in it that will increase the risk of leptospirosis. The risk also varies with area and your vet is the best person to know about this. My own area is high risk for lepto and my dogs, including the oldies, have always been vaccinated for it in the spring and I've never had an adverse reaction in any of them. But the best person to advise you is your vet and it sounds as if in your area and in your circumstances (s)he doesn't think there is a serious risk of your dogs getting leptospirosis.

My old lab ate a whole bag of Rat poison (the small scatter packs) and was put on Konakion tabs Vit K she was on these for a month with no adverse affects.

Mine hunt rats all day and chase them them dispose of them but very rarely eat them!!