An environmental cause can include a drug, alcohol or a disease the mother has that can increase the chance for the baby to be born with a birth defect. An agent that can cause a birth defect is known as a teratogen. Multifactorial birth defects are caused by a combination of genes and environmental exposures.
National Rescues. Lyme Disease May Cause Sudden Aggression in Dogs Written by Betsy Sommers of. Peppertree Rescue, Albany, NY, USA. 28th May 2004: We recently had a very strange event that I think we should share around the rescue community. A Young (~2 years) Lab mix, male, came into our program with a questionable background.
In some cases, the development of a neurological problem through illness or injury can affect the dog's judgment and behavior. Hydrocephalus, head trauma, encephalitis, epilepsy and brain tumors can all cause aggression and strange behavior in dogs. Hydrocephalus is the most common of these conditions to cause sudden aggressive behavior.