 a BREED of blood-sucking ticks normally found in continental Europe has been discovered in Britain for the first time.  Researchers from the University of Bristol also found that the number of dogs infested with all species of the parasite was far higher than previously thought.  They raised fears that there is an increased risk of disease carried by the ticks, including some brought in for the first time by the foreign tick, Dermacentor reticulatus, thought to have arrived here because of climate change.  Dog ticks can be infected with diseases that, if left untreated, can damage the heart and nervous system of humans. The research, published in the journal Medical and Veterinary Entomology, studied 3,500 dogs. It found that at any one time 14.9 per cent of dogs were infested with ticks.