Abstract
Like most scientific disciplines, pharmacology is replete with subspecialties. Certainly most scientists recognize the value of animal studies in drug development for human pharmaceuticals. However, animals as the target species also represent a major focus of investigation. According to recent estimates, in the United States for the year 2000, 98.1 million cattle, 59.8 million pigs, and 1.5 billion chickens existed. Added to that estimate were companion animals, including 4 million horses, 59 million cats, and 52.9 million dogs. The estimate does not include the so-called "minor" species, such as 7 million sheep and 320,000 acres of freshwater fish production. In most respects, the medical needs of these animals are addressed in a manner parallel to that of human medicine. One such parallel, with certain distinct differences from its human counterpart, is veterinary clinical pharmacology.