Q

qualitative traits - Those in which there is a sharp distinction between phenotypes (e.g., red or black color).  Usually, only one or two gene pairs are involved.

quality - Quality is something special about an object that makes it what it is; a characteristic, attribute, excellence.  Quality is the composite or attribute of an animal or product that has economic or aesthetic value to the user; meeting or exceeding each customer’s expectations at a cost that represents value to the customer every time.

quality grades - Grades such as Prime, Choice, and Select that group slaughter cattle and carcasses into value- and palatability-based categories.  Grades are determined primarily by marbling and age of animal.

quantitative traits - Those in which there is no sharp distinction between phenotypes, with a gradual variation from one phenotype to another (such as weaning weight).  Usually, many gene pairs are involved, as well as environmental influences.