Watersprout, I must admit I haven't read the entire thread, but the following might help you..
Rat poison, Snail poison and arsenic are all substances that are easy to obtain and will get your dog killed. Look for pellets on the ground in your garden. The poison pellets are brightly colored.
Dog's can't handle chocolate. You probably already knew that, but just in case you didn't, don't feed her any chocolate. Your neighbor might be throwing chocolate over the fence. Chocolate can build up over time so the dog can be slowly poisoned over an extended period of time before any symptoms appear.
If I were you, I would not let my dog out in the garden again for many months. Your neighbor might spray fluid pesticides into your garden, which you can't see. Some pesticides are absorbed through the skin. Snail poison can stick to the paws of your dog, and your dog will get it in by licking her paws. And maybe even keep the windows closed when I wasn't in the same room as the dog.
Many poisons such as arsenic can build up in the body over time and are only slowly degraded. The more often your dog gets poisoned, the more serious it will get. Maybe you need to send her over to your parents for a longer time. Poison like arsenic is also very hard to trace when administered in small doses, so the vet has probably no way of detecting it unless it was given in a single big dose.
Arsenic is sometimes used in heart-worm drugs for dogs. Antiflea products (shampoo, collar, etc.) can also sometimes have adverse effect on dogs because of the pyrethroids they contain.
Unfortunately the symptoms for all these poison are all very much alike but here is a list. Maybe you can find out which is being used by your neighbor. Of course she might even use more than one poison.
These are the symptoms for snail poison in dogs:
- apprehension and an increased excited mood
- excessive drooling
- muscle tremors
- fast heart rate
- respiratory failure
These are the symptoms for rat poison
- reject food
- saliva is mixed with blood
- internal bleeding from gums, lung
- external bleeding from nose (epistaxis), rectum (hematochezia)
- bright green stool which is caused by eating rat bait pellets
- bloody urine (hematuria) or stool (melena)
- blood coagulation
- uncoordinated gait
- muscle tremors
- inability to stand
- mild cough
- lung problems
- breathing difficulty
- mental depression
- extensive bruising
- hair loss
Symptoms of arsenic poisoning in dogs:
- Abdominal pain
- Fresh bright red blood in feces
- Lying down with extreme exhaustion
- Body may feel unusually cold especially at extremities including ear, and limb extremities
- Loss of consciousness
- In chronic (long-term) exposure symptoms may be subtle like poor appetite and weight loss
You can recognize that your dog has eaten a toxic dose of chocolate from the symptoms. Within the first few hours, the evidence includes vomiting, diarrhea or hyperactivity. As time passes and there's increased absorption of the toxic substance, you'll see an increase in the dog's heart rate, which can cause arrhythmia, restlessness, hyperactivity, muscle twitching, increased urination or excessive panting.
This can lead to hyperthermia, muscle tremors, seizures, coma and even death.