The pericardium is a tough, layered sac that wraps around the heart. When the heart beats, it slides easily within the sac. Normally, only 2 to 3 tablespoons of clear-yellow pericardial fluid are present between two layers, which lubricates the heart's movements within the sac.
Biewer. The Biewer (pronounced Bee-vair), also known as the Biewer Terrier, Biewer a la Pom Pon, Biewer Yorkshire Terrier, Biewer Yorkshire, or Biewer Yorkie is a variant of the Yorkshire Terrier.
If you keep a puppy and breed this again to a true Biewer (3 generation Biewer) you will get Biewer and Yorkshire puppies. If you keep again a puppy no matter if Yorkie color or Biewer; and breed this again to a Biewer you get only Biewer puppies.. Find out more about multi-generation crosses.