Polled (Hornless) – – occurs naturally but now can be achieved by GM (Genetic Modification)

Likely (Hoard’s Dairyman) and unlikely (The Wall Street Journal, Mother Jones and the MIT Technology Review) sources made the topic of polled (hornless) dairy cattle a hot topic recently. A good starting point in discussing polled is this…

Polled is a dominant trait (genetically controlled much like coat color in cattle) that is naturally quite prevalent in some dairy and beef breeds. The Norwegian Red has the highest prevalence of polled among dairy breeds (40% to 50% of calves born are polled) and the Angus breed is the best known of all-polled beef breeds.

Why is polled in the news?
The buzz is a new gene editing capability, CRISPR, that find and cuts out (with a protein) the bovine genetic code for horned and then replaces it with new bovine DNA that codes for polled.

Corry Geiger in April 26, 2016 Hoard’s Dairyman Intel highlights FDA’s approval of the genetically modified organisms (GMO) faster-growing AquaBounty Salmon and reduced-bruising Innate Russet Burbank potato. He then mentions that GMO polled cattle may be coming. Those cattle would be created by the company Recombinetics using CRISPR technology outlined in Kirk Sattazahn’s April 10, 2015, Hoard’s Dairyman article “How genetic editing will impact your future.”

David Fahrenkrug, the CEO of Recombinetics, likens CRISPR, a precise gene editing procedure, to replace horned with polled to word-processing where a single word can be changed in a sentence without interfering with the structure of a document. CRISPR, he says, is less likely than previous GM techniques to produce undesired effects such as accidentally turning off a useful gene or creating a new toxic or allergenic protein.

However, environmental groups have already filed a lawsuit against the U.S. FDA, challenging the agency’s authority to approve genetically modified animals used for food (The Wall Street Journal, Lawsuit Challenges FDA’s Right to Approve Genetically Modified Animals, March 31, 2016).

Why polled?
• Dehorning is a necessary management practice for human and animal safety
• Dehorning (or disbudding) is an unpleasant procedure for calves and workers (pain-alleviating drugs should be used with caustic paste, hot irons or clippers)
• Elimination of dehorning through the use of polled sires is a cost effective and animal welfare appropriate practice

Norwegian Red Saur (11572) is homozygous polled

A majority of dairy cattle genetic companies recognize the need and increasing demand for polled for all of the above reasons. Thus, they are increasing their offerings of heterozygous and homozygous bulls that will produce 50% or 100% polled offspring, respectively, when bred to horned cows.

Polled plus crossbreeding is best?
There is no other modern, competitive dairy breed that compares with the Norwegian Red in percentage of polled, both in elite sires and in the general dairy cattle population. Currently, Norwegian Red semen is exported to more than 30 countries worldwide and sales are growing especially in the US.

Growing sales is partially due to polled, but is increasingly from this breed’s unique, long-term combination of competitive production, moderate size (increased feed efficiency), unsurpassed fertility and resistance to important diseases. Therefore, crossbreeding with Norwegian Red increases animal welfare and profit per cow and refutes what some say – – a majority of polled bulls are not of high enough quality or that crossbreeding is slow and unpredictable.

Polled will continue to increase globally…
Polled sire numbers are increasing as breeding companies see and are attempting to meet the demand for polled sires from their customers. More polled Holstein and Jersey sires are becoming available, but more and more commercial dairymen are also taking a critical look at the fertility, health and stature these bulls will transmit to their daughters. The Norwegian Red has and will continue to have polled plus other important welfare traits as integral parts of its breeding program.

Ultimately, producers and breeding companies may not have the final say about whether the new gene editing procedure to insert polled genes takes off. “It’s important to note that GMO polled cattle could be years from reaching the marketplace and being raised on mainstream dairy farms”,” says Corey Geiger of Hoard’s Dairyman. “That’s because consumers or judges may reject the entire GMO food premise.”

Additional resources:

18 APR 2016 Cosmos Magazine, What is CRISPR and what does it mean for genetics?

18 December 2015 YouTube video at Ilar Roundtable, Species-Specific Use of Gene Editing Technologies: Polled Cattle (Scott Fahrenkrug).  Speaks about CRISPR as a technology to make polled cattle at 28-34 minutes.

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