Cow College explores benefits of genomic sire selection, cross-breeding with beef bulls

CLINTONVILLE – Dairy producers from Outagamie, Shawano and Waupaca counties, along with other industry professionals, attended the opening session of the 56th Annual UW-Extension Cow College Jan. 9 at the Fox Valley Technical College Regional Center.

“Cow College is a series of three education programs offered each January to help northeast Wisconsin dairy producers become more proficient in the farming operation,” said Waupaca County UW-Extension Agricultural Educator Greg Blonde.

The opening session featured Dr. Kent Weigel, head of the UW-Madison Dairy Science Department, and dairy specialist Dr. Victor Cabrera.

Weigel reported on recent studies that examined the benefits of using genomic (DNA) analysis as a tool to improve dairy herd health and productivity.

To successfully utilize genomic selection requires building a large reference population that includes thousands of bulls with progeny data and tens of thousands of cows with performance records, according to Weigel. “Essentially we are using inherited genetic markers to build a better pedigree,” he said.

Genomic testing and benefits

He explained that calves can be tested shortly after birth by collecting samples of hair, tissue or blood unless the calf is a twin. “Cost for this low-density test of about $45 per animal,” Weigel related.

“Genomic test results flow from the laboratory to the Council on Dairy Cattle Breeding, the parentage is verified or discovered, genotypes are imputed to higher density and preliminary prediction so computed weekly,” he noted.

Regarding the accuracy of genomic predictions, Weigel said, “It enables us to make the right decisions more frequently, but not always.” He added that genome-guided culling aids in repurposing calves of low genetic merit. 

Combining genetic information with the use of sexed semen can provide additional benefits to dairy producers. “This can help producers improve profits by propagating more heifers of higher genetic merit,” he explained.

IVF and embryo purchases

Weigel also addressed the economics of routine In Vitro Fertilization (IVF). “Net present value (NPV) of an IVF calf is often positive, but it can become a negative if future generations are ignored,” he said.

He also suggested the NPV improves with the higher reliability of genomic prediction, and is especially important with high selection intensity. “NPV also improves with the high genetic merit of IVF bulls,” Weigel said.

Fine tuning of IVF protocols can also improve the net present value of calves according to Weigel. “Higher conception rates, higher embryos per collection, combined with lower veterinary fees and lower embryonic loss help reduce the cost of IVF calves,” he said.

In analyzing benefits of purchased embryos, Weigel said the NPV of $200 embryos is generally positive if 70 percent are implanted into heifers, achieving a 55 percent conception rate and 8 percent pregnancy loss in heifers, and a 40 percent conception rate with a 17 percent pregnancy loss in cows.

Weigel noted that genomics and IVF can create high-value calves to market as breeding stock. “But it’s a high-risk, high-reward venture,” he added.

“Genomics is great for sorting heifers into high, middle and low groups, but predicting the productivity of individual animals is less certain,” he explained. “There are many synergies between genomics, sexed semen and IVF and this allows flexibility in optimizing the next generation of replacement heifers.”

In summarizing his presentation, Weigel pointed out that while high genetic merit herd can make rapid progress with genomics and IVF, the technologies are costly and reproductive performance may be compromised.

“The average genetic-merit herds should start by developing a solid foundation of females with aggressive use of genomic young sires and sexed semen,” he advised.

Beef semen

Dairy producers looking to generate additional income might want to consider cross-breeding low potential heifers and low-producing cows to beef bulls with superior carcass traits, suggested Dr. Victor Cabrera.

Cabrera has developed a series of scientific-based dairy farm management decision support tools that are user-friendly and interactive. One of those is the Premium Beef Option available at: http://www.dairymgt.info/tools.php

He suggested that producers consider beef semen as an option in addition to conventional semen and sexed semen.

“The tools will help you strike a balance between price and performance,” he said. “You’ll need to consider if you have a market to sell excess heifer calves if you use sexed semen, and the availability and price of needed replacement heifers when using beef semen.”

The program will enable producers to analyze the costs and benefits of different scenarios for animals with low, medium and high fertility rates, using conventional, sexed and beef semen. “It will help you determine the highest income from calves over semen cost,” Cabrera said.

The program features default conditions, but also allows producers to plug in their own numbers related to semen cost, cost of replacement heifers and selling prices for heifers and beef calves.

“Farms with high reproducing animals are more sensitive to calf prices, while farms with lower fertility animals are generally more sensitive to semen prices, while sexed semen use is limited more by price than performance,” he said.

Cabrera concluded by suggesting the beef semen can be a profitable alternative when beef prices are high and the cost of beef semen is low, when herd genetics are low, and when it is used in conjunction with sexed semen.