Animal breeding and genetics

Since animals were first domesticated, animal breeders have been using selective breeding to determine which animals will become parents of the next generation. Initially, this decision was based on the animals’ appearances. For example, when domesticating the wolf to generate the different dog breeds, parents were selected based on temperament. Different temperaments are helpful for herding dogs vs. guard dogs. Appearance is another important trait because some dogs are large and some are small. As scientific understanding of genetics improved, it became clear that animals inherit traits from their parents. Traits are passed on through genes, which are small bits of information in your cells.

Modern animal breeders use a lot of information to select which animals will become parents of the next generation. They consider the records they have kept for their animals. They might want to increase dairy cow milk production or wool production in sheep. The goal of their breeding program then becomes to produce animals that have these good traits.

Once an animal is born with a good trait, that trait can be passed to the next generation. Over time, more animals in the herd will be born with that good trait. This helps producers achieve their breeding goal. The process of selecting animals based on their genetics has helped advance agricultural productivity over the past 50 years.

A good example of genetic improvement is in poultry breeding. Between 1957 and 2001, poultry breeders selected traits to increase the body weight of broiler (meat) chickens. Due in large part to genetic selection, broiler body weight at eight-weeks of age has increased from 1.8 pounds to 6.9 pounds.

Improvements in poultry breeding have generated chickens that produce more meat for human consumption. Because today’s chickens grow faster and more efficiently, poultry producers can produce more chicken, using less feed and in a shorter amount of time. More productive chickens means more meat in the supermarket.