Please check this link first if you are interested in organic or specialty dairy production.

 

SNP Evaluation Systems (continued)

Limitations of SNP Selection

The main limitation of SNP selection is having good phenotypic information from a large number of animals in the population of interest (Hayes et al. 2009). For example, accuracy improved markedly when the number of progeny-tested American Holstein bulls increased from 1,151 to 3,576 (VanRaden et al. 2009). Very few populations of cattle have thousands of …

Please check this link first if you are interested in organic or specialty dairy production.

 

SNP Evaluation Systems (continued)

Refinements of SNP Selection and Future Aspects

SNP technology will not replace current methods of selecting breeding cattle but will be used in addition to them. We will use all the pedigree information (including the new SNP information on parents) in decision making, as well as the individual’s phenotype (e.g., birth weight). The term “genomic enhanced EPDs” already has been …

Author Information

G.E. Seidel, Jr.
Animal Reproduction and Biotechnology Laboratory
Colorado State University

Abstract

Genomic selection using SNPs (single nucleotide polymorphisms) is a powerful new tool for genetic selection. Current SNP profiles for individual animals are generated using a small plastic chip that is diagnostic for up to 50,000 SNPs spaced throughout the bovine genome. Phenotypes, usually averaged over offspring of bulls, are matched with SNP profiles of bulls mathematically so that animals can be ranked for siring desirable phenotypes …

Contents 1 What’s All the Fuss? 2 A Little Basic Biology 3 How the SNP Data Help Predict Genetic Merit 4 Genomic Data and Genetic Evaluations 5 Plans for Genetic Evaluations Using Genomic Data 6 Prospects for Using SNP Chips in Commercial Herds 7 The Future 8 Author Information

What’s All the Fuss?

Major changes in genetic evaluations of dairy cows don’t come along every day. Producers …

Introduction

Improvement of dairy herd genetics can affect herd health, longevity, reproductive traits, and many other vital aspects of dairy cattle production. It can also lead to increased milk production, milk quality, and overall animal performance. Efficient sire selection is the primary avenue for an immediate impact on genetics in a dairy cattle operation.

Genetics Videos

 

• Complete and Accurate Recording of Calving Ease and Stillbirth Data is Key
• Dairy Cattle Inbreeding
• Dairy Crossbreeding: Results from New Research and Information Still

…

Contents 1 Introduction 2 More than 30 Traits to Consider 3 Consider Corrective Mating 4 Author Information

Introduction

It happens around the middle of February, and then again in May and August. Maybe you’ll see bull lists in magazines, or maybe your semen salesmen show up with an armload of new promotional materials. Either way you’ll know – it’s sire summary time again.

Data for important traits …

Contents 1 Introduction 2 Genetic Improvement – An Historical Perspective 3 Health and Fitness Traits 4 Productive Life (PL) 5 Somatic Cell Score (SCS) 6 Type Composites 6.1 Udder composite: 6.2 Feet/legs composite: 6.3 Size composite: 7 Daughter Pregnancy Rate (DPR) 8 Calving Ability 9 Genetic Relationships between Health and Fitness Traits and Other Traits 10 Using Genetic Evaluations for Fitness Traits 11 Author Information

Introduction

Dairy …

Contents 1 Introduction 2 Within-Country Differences in Herd Management 3 Between-Country Differences in Herd Management 4 Implications for Sire Selection 5 References 6 Author Information

Introduction

Genetic improvement programs for dairy cattle are typically carried out on a national or international basis. However, differences in management practices and/or climate conditions exist between countries, as well as between individual farms within a country. Differences in the economic value …

Contents 1 Results from New Research 2 California Commercial Herd Results 3 Holstein-Jersey Crosses at Kentucky and Virginia Tech 4 Analysis of Dystocia and Stillbirths Using Odds Ratios 5 Minnesota Holstein-Jersey Results 6 Performance of Backcrosses to Holstein in Wisconsin 7 Crossbreeding Systems in the United States 8 The Bottom Line for Crossbreed Programs 9 References 10 Author Information

Results from New Research

Three crossbreeding projects are …

Introduction

Several questions commonly come up among dairy producers who practice management intensive rotational grazing when the topic of sire selection arises:

Should I use bulls that were tested under confinement feeding conditions?

Should I use bulls from countries where grazing is common, such as New Zealand?

Should I consider crossbreeding? If so, which breeds should I choose?

Hundreds of bulls from a dozen different breeds are at your disposal, and each has predicted transmitting abilities (PTA) for traits such …