Genomic Selection Has Changed Dairy Sire Selection


Take Home Messages

  • Use of genomic markers has reduced the generation interval, defined as the average age of parents when their offspring are born.
  • The generation interval of sires of bulls has decreased from approximately 7 to 2.5 years, while dams of bulls has decreased from 4 to 2.5 years.
  • Genomic selection has increased the rate of improvement in economically important traits such as daughter pregnancy rate, productive life, and somatic cell score.
  • Progeny-tested sires remain in demand and continue

Genomics and Reproductive Performance

Curious Jersey Cows

Where We Are Coming From: The Problem

For decades dairy production systems have faced the challenge of attaining adequate fertility levels. Insufficient reproductive performance will result on reductions on the proportion of cows at their peak production period, increments in insemination costs, and delayed genetic progress. Moreover, impaired fertility is one of the most frequent reasons for culling and increased days open are associated with a greater risk of death or culling in the subsequent lactation.

An historical trend for …

The Big Picture: Genomics, Humans, and Animals

Various breeds of cattle

Take Home Messages

  • The completion of the Human Genome Project, along with DNA sequencing of numerous other species has facilitated a flurry of genomic research.
  • Scientists are currently investigating how SNPs are associated with disease in humans and animals, along with production traits and fertility in livestock.
  • Genomic testing has been embraced by people to study their own health traits and ancestry, and to select for cattle that best fit the herd management strategy.

Please check this link first if

Dairy Reproduction Featured Videos

Reproductive success is vital to the profitability and sustainability of any dairy farm. Good management practices are an important component of running an effective reproduction program, and these five videos can help improve management and decision-making. From economic tools to troubleshooting, learn more with DAIReXNET.

Don’t want to miss new videos? Head over to our YouTube channel and subscribe!


Dairy Reproduction: Identifying Problems and Solutions for Your Herd

Many dairies experience difficulty in their reproduction programs, and a wide range …

Maneje el Semen Sexado con Cuidado para Maximar le Fertilidad de las Novillas

In English: Handle Sexed Semen with Care to Maximize Heifer Fertility

Los productores lecheros, encargados del hato, veterinarios y consultores monitorean datos de producción, eventos de salud y el cumplimiento de los protocolos de reproducción en forma regular; sin embargo, muy poco tiempo se utiliza en evaluar el almacenamiento y manejo del semen. Desafortunadamente, este puede ser un descuido crítico dado que cada programa de Inseminación Artificial (IA) comienza con un manejo de semen adecuado.

Si usted está interesado en

Genética y Genómica: Una Introducción

¿Cuál es la diferencia entre “Genética”, “Genómica”, y “Genoma”?”

La genética es una rama de biología enfocada en la herencia y la variación de los organismos. En términos más simples, la genética se centra en las características o rasgos que se transmiten de padres a hijos, de una generación a otra.

La genómica es una disciplina científica enfocada en el mapeo genético, la secuenciación de ADN, y el análisis del genoma completo de un organismo, incluyendo organizar los resultados en …

Assessment of an Activity Monitoring System for Detection of Estrus and Timing of Artificial Insemination in Lactating Dairy Cows


Despite the widespread adoption of hormonal synchronization protocols that allow for timed artificial insemination (TAI), detection of behavioral estrus continues to play an important role in the overall reproductive management program on most dairies in the United States (Caraviello et al., 2006; Miller et al., 2007).

Several challenges for estrous detection on farms include attenuation of the duration of estrous behavior associated with increased milk production near the time of estrus resulting in shorter periods of time …

Evaluating the Economic Value of Changing the Reproductive Management Program for a Specific Dairy Farm


Dairy farm profitability depends on a herd’s reproductive performance, but this relationship is complex. Farmers and consultants can easily assess reproductive performance by benchmarking pregnancy rate (i.e., 21-d pregnancy rate) or other reproductive metrics, but they find it difficult to measure the economic impact (e.g., profitability) of changes in reproductive outcomes, alternative reproductive management programs, or reproductive management decisions that affect individual cows. This paper presents a decision support tool that may assist dairy farm managers in making better …

Handle Sexed Semen with Care to Maximize Heifer Fertility

en Español: Maneje el Semen Sexado con Cuidado para Maximar le Fertilidad de las Novillas


Dairy producers, herd managers, veterinarians, and consultants monitor production data, health events, and reproductive protocol compliance regularly; however, little time is spent evaluating semen storage and handling. Unfortunately, this can be a critical oversight, as every successful artificial insemination (AI) program begins with proper semen handling.

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

Sexed Semen

Checklist for Nutritional Aspects for Improving Reproductive Efficiency

En Español: Lista de Chequeo de Aspectos Nutricionales para Mejorar la Eficiencia Reproductiva


This article is part of our series of original articles on emerging featured topics. Please check here to see other articles in this series.


Almost all dairy farmers would like to improve the reproductive efficiency of their dairy herd, but they must manage many aspects to achieve this goal, including the nutritional program. The feeding program during the dry period, for the fresh cows, and throughout …