A cleft palate is an abnormal opening in the roof of the mouth. It is the result of failure of the two sides of the palate (roof of the mouth) to come together and fuse during embryonic development. A cleft palate results in an opening between the nasal passages and the mouth. Symptoms expected with a cleft palate include: runny nose, coughing, aspiration pneumonia (pneumonia caused by milk and food contents entering the cleft and infecting the lungs), respiratory difficulty (caused by aspiration pneumonia), difficulty sucking and nursing (for puppies), slow growth, weight loss, lack of appetite. Cleft palates can be inherited, and also have non-inherited causes, such as environmental effects - i.e. vitamin deficencies.