subject: genome sequencing

Ancient DNA Provides the Clue to Modern Cattle

Ancient DNA Provides the Clue to Modern Cattle

Modern dairy cows are as elite as Olympic athletes. They are champion milk producers and enable humans to turn fodder into dairy food with incredible efficiency. Underlying this performance is thousands of years of selection and improved management practices. Initially, the selection process was farmer driven and resulted in the development of many cattle breeds, but since the mid 20th century, when coordinated efforts by farmer groups and the dairy industry focused attention on the best methods to achieve improvements in production, the gain in efficiency through genetic selection has been remarkable. Read More...

Dairy Farmers Prefer Healthy Manageable Cows

Dairy Farmers Prefer Healthy Manageable Cows

Reaping the rewards of the genomic revolution in selective breeding in of dairy cows requires an informed and engaged dairy farmer response. A study published in December 2016 from a Danish group of dairy scientists reports that farmers rank health and management qualities above production traits in their cows. However, this ranking differs depending on whether the farmer is classified as organic or conventional. Read More...

The Bacterial Diversity in Raw Cow Milk During Its Transport and Storage

The Bacterial Diversity in Raw Cow Milk During Its Transport and Storage

Pasteurization helps make raw cow milk safe for human consumption, but it doesn’t get rid of all bacteria. These remaining bacteria can cause spoilage, thus affecting the shelf life and quality of milk products and leading to wastage. Knowing what bacteria are present in milk before and during milk processing could help identify sources of spoilage and find ways to get rid of them. Read More...

Genomic Selection Accelerates Improvements in Health and Productivity of Dairy Cows

Genomic Selection Accelerates Improvements in Health and Productivity of Dairy Cows

The introduction of genomic selection into dairy cattle selective breeding programs has been greatly anticipated and is a remarkable example of the benefits of genomic technology. Made possible because the systems for selective breeding were already well developed in dairy, and the widespread use of artificial insemination meant that new developments could be delivered quickly. First introduced in the USA in 2008, there has now been sufficient time to generate enough data to assess its impact. Read More...

Ancient Aurochs Genome Contains the DNA Blueprint for Modern Cattle

Ancient Aurochs Genome Contains the DNA Blueprint for Modern Cattle

A preserved specimen of aurochs bone was discovered deep beneath the Derbyshire Dales in the UK in the 1990s. Aurochs are an ancient cattle breed domesticated around 10,000 years ago somewhere around modern day Iran. In Europe, the last of these animals were still found on a Polish royal reserve as recently as the 17th century. Park et al., have now extracted enough DNA from the ancient bone specimen to sequence the aurochs genome. When they compared the aurochs sequence to the DNA of cattle breeds we know and use in domestic agriculture today, they found a surprisingly high level in common with British and Irish cattle. Read More...

Accounting for Lactase Mutants

Accounting for Lactase Mutants

Back in the 50s and 60s, work on lactose intolerance was often published under cringeworthy and blunt racial titles. A Nature article from 1969 sums it up with ‘Can Asians Digest Milk?’ It was also probably a subliminal non-accident that ‘lactose intolerance’—which is the typical condition for adult humans—became common parlance for a trait for which those with northern European ancestry are the real mutants. Many decades on, the genetic basis of the ability to digest lactose has been largely pinned down. As it turns out, there are different genetic reasons for the mutants’ lactose tolerance in the various populations that drink milk without intestinal incident, and the gene that confers mutant power in Europeans is only part of the story. That research history is discussed below, along with recent work that has extended the field’s reach beyond genetics. Investigations of the transcontinental basis of lactose tolerance are now providing insights into mankind’s cultural, as well as biological evolution. Read More...

Making Sense of Dairy Biosystems

Making Sense of Dairy Biosystems

We live in an information-rich world. Each of us is capable of downloading gigabytes of data on our mobile or desktop devices each day. The upswing in data generation is also true of dairy science, which has moved into the big data realm. My students can create more data in an afternoon than I created in an entire PhD project when I was a student. Needless to say, capturing and analyzing this data is both challenging and rewarding. Since genomic data became more accessible, a number of approaches have been developed to bring the data together in useful ways. Gradually these approaches have become more sophisticated and insightful. A recent study by Widmann et al. provides a great example of how integrating different sources of large-scale genomic data can shed light on how dairy cows convert their feed into milk. Read More...

Predicting Performance in Dairy Cows of the Future

Predicting Performance in Dairy Cows of the Future

Selective breeding of dairy cows is a major part of modern dairy farming. Farmers can select the bulls that they want to use to produce animals for their herd. One bull may sire thousands of daughter cows via highly developed systems for artificial insemination. The availability of lots of stored semen from bulls that have been shown to produce cows with excellent production and health traits has been a backbone of improving efficiency and production in dairy farms for several decades. There has been a continuous effort to build on the methods and procedures that contribute to selective breeding, most recently with the advent of genomic tools. Read More...

Towards Individualized Genomes for Dairy Cows

Towards Individualized Genomes for Dairy Cows

International cooperation between scientists has really taken off in genomic sciences, and now, in a program that has grown out of dairy genetic research, one thousand bulls are set to be immortalized by having their DNA sequenced. The so-called 1000 Bulls Genome Project is an international collaboration between scientists in Europe, USA, and Australia. The project began in 2010, when scientists were looking for a way to share the huge cost of sequencing many entire genomes. The result was the 1000 Bulls Genome Project, which spreads the costs and shares the resources to help geneticists apply their collective knowledge of cattle to improve the productivity of cattle herds. Read More...