In descending order, by date published.
The yak (Bos grunniens) is a unique domestic animal. These animals were developed in the extreme environment of the Himalayas, where food resources can be extremely limiting. The yak provides food (meat and milk), fiber (hair), and are beasts of burden (used for pack, transportation, plowing, etc.) for the local populations. The number of yaks in the world is limited, creating a need to understand and control reproduction in the yak to improve genetic diversity.
The yak (bos grunniens) is a member of the bovine family and plays a vital role in the life of the people of the Himalayan region (China, Mongolia, India, Nepal, etc). The Himalayas is an especially harsh region with long, cold winters and sparse vegetation for most of the year. As with all bovine, nutrient availability, both quality and quantity of available foodstuffs, and current status of body reserves or degree of fat stored in the body dictate the ability of the cow to conceive during a breeding season. Even though conception rate (probability of conception at a single estrus event), is high (70+%), pregnancy rate (probability of conception at the end of a breeding season) is typically only 40%-60% in their natural environments because a high proportion of female yaks fail to have an estrus during the breeding window. Understanding the major factor reducing pregnancy rate is important to creating and implementing management protocols to improve the reproductive ability of female yaks.
The domesticated yak (Bos grunniens) arrived in North America in the late 1890s. A few animals were imported into Canada and North American zoos and became the foundation of the North American genetic pool. Research was conducted in Alaska hybridizing them with Highland cattle in the early 1900s. A handful of yaks were imported into the United States in the early 1900s and again later in the 1980s. However, the genetic diversity of the North American yak is limited, necessitating a need to manage breeding programs to reduce inbreeding.