In the member survey, the majority was not utilizing crossbreeding in their dairy operations; however, just over a quarter of the group was dabbling with the approach by crossbreeding up to 20% of the herd. The most common reason given for crossbreeding was calving ease, with 27% of the responses. Equally influential was the producer’s desire to improve fat and protein components of the milk. Perhaps a little surprising was that over 20% of the time, the reason given for crossbreeding was use of a different breed to improve service sire conception rates. Table 1 provides a summary of the Genex member survey on crossbreeding.

Let’s address the issues of why dairymen are looking at crossbreeding. Our survey of mostly Holstein dairymen indicates their cows have too many calving problems, poor cow fertility, fat test is too low, cell count is too high, feet are trimmed too often, cows do not last as long as they should… Have I covered most of them? For the commercial milk producer with Holsteins who has a well-managed dairy, excellent facilities and high-quality feed and has used high-ranking A.I. service sires for many years, he has reaped the benefits of very high-producing cows. When everything on the farm is moving like a well-oiled machine, a manager begins to look for the next 10 pounds of milk per cow, and solving one or more of the aforementioned problems are a good way to start.Enter the suggestion of crossbreeding to solve what ills the Holstein cow with her “too-high” genetic potential for milk and her perceived inability to stay healthy.

There are some things we can expect when crossbreeding the Holstein cow to a service sire from one of the other dairy breeds:
1. Production potential of the offspring will be slightly higher than the average genetic levels of the two parents. Table 2 shows average production levels of various dairy breeds.
2. Jerseys crossed with any other dairy breed will likely result in fewer calving difficulties.
3. The offspring will likely have an advantage in reproductive efficiency.
The benefits of improved reproductive efficiency could come from a number of sources, including less stress from calving, less stress from more moderate milk production, etc. There may be some additional (but unproven) benefits from crossbreeding that are specific to the breeds of the parents. We have seen many of these advantages reported in various dairy publications, mostly in the way of advertising. The research cited in support of the advertising is a good start in evaluating effects of crossbreeding. This research is on-going and really only preliminary in analysis.
I think if we asked a dairyman who was crossbreeding to describe the perfect A.I. service sire, he will list the following factors in no particular order:
• Maintains adequate production levels
• Improves udder and feet and legs
• Daughters breed back easily
• Low somatic cell scores and few cases of clinical mastitis
• Reduced calving problems
• Daughters stay in the herd longerSounds familiar, doesn’t it? The same traits or events are included in Lifetime Net Merit, allowing a dairyman to focus simultaneously on the many genetic components of cow profitability. The inclusion of the fitness traits of Daughter Pregnancy Rate, Daughter Calving Ease, and Service Sire Calving Ease into the Lifetime Net Merit index, in addition to the already present traits of Productive Life and Somatic Cell Score, provides an all-in-one package approach to breeding for healthier cows, as compared to previous selection indexes available to Holstein producers. By using high LNM$ sires, a dairyman will breed a herd of cows with optimal production levels from healthy, medium-sized cows with correct udders and feet and legs. As a group, his cows will calve easily and breed back quickly; therefore, not limiting the number of resulting replacement heifers and enhancing overall cow longevity. Current selection for Lifetime Net Merit may better address the concerns that are steering a dairyman to consider crossbreeding.

Traits Included in Lifetime New Merit

For the producer who has determined crossbreeding is the desired approach, what options are available? The producer’s decision should be based on what issue he is trying to address. For calving ease concerns, all data available indicates the Jersey breed has very little, if any, calving difficulty. In a recent USDA-AIPL review of calving reports for Jersey and Brown Swiss service sires, it was found nearly all Jersey bulls have a 1% or 2% estimated difficult birth in heifers (%EDBH). There was greater variation for Brown Swiss, and starting in February 2005, calving ease evaluations were made available for Brown Swiss sires. Much of this data has been generated by evaluating calving ease reports of Brown Swiss x Holstein crosses.
For producers wanting to improve cow fertility by crossbreeding, again the Jersey breed appears to have the genetic advantage of approximately 5% greater pregnancy rates than Holsteins. Based on breed phenotypic averages, the other major U.S. dairy breeds are about equal to Holsteins. You might ask, how do the European Red breeds compare with Holsteins for genetic levels of calving ease and pregnancy rate? Well, we do not know yet. Best estimates to date show it is likely better than Holsteins, but not as good as Jerseys. The cow’s ability to breed back easily should not be confused with the ability of the semen to achieve conception. Our member survey suggests there is a perception among dairy producers that problem-breeder cows may settle more easily by using a sire of a different breed as a service sire. Yet, recent university research does not confirm this and suggests it may be myth more than fact. There are, however, Estimated Relative Conception Rate (ERCR) rankings available for Holstein and Jersey sires to rank a bull’s effectiveness at achieving pregnancies.It is also important to remember all breeds are not genetically equal. Even more confusing is estimating the genetic levels of European dairy breeds when there are not genetic summaries for those breeds in the U.S. Instead, the European Red breeds are summarized using the Ayrshire genetic base in the U.S. Table 3 shows Lifetime NM$ values for each breed relative to Holsteins using estimations done by USDA-AIPL staff.

Utilizing the Holstein breed as a base of zero, an Ayrshire bull is $510 lower in Lifetime NM$. For example, an Ayrshire or Scandinavian Red bull with a Lifetime Net Merit index of $600 is likely equivalent to only a $90 LNM Holstein sire. The Scandinavian Red breeds should not be confused with Red & White sires originating from countries like The Netherlands and Germany whose bulls are summarized on a U.S. Holstein genetic base. Dutch and German Red and White genetic programs focus on many of the same selection principles used by other European Red dairy breeds but tend to have a high percentage of Holstein-Friesian ancestry.
When crossbreeding, it is key to remember mating two unrelated breeds or populations together maximizes the effects of heterosis. Some traits show greater heterosis than others. Interestingly, USDA has not found much heterosis effect on somatic cell score so far. Use of today’s high-ranking Lifetime NM$ Holstein bulls can help you cut somatic cell by 50%, reduce days open 3% and increase longevity by one-half lactation. The additive genetic effects will continue to be passed on to subsequent generations unlike heterosis, which is maximized in the first cross. I am not sure about the magnitude of benefits that may be gained from crossbreeding strategies. If I was in the situation, I would make sure I gained as much benefit as possible from heterosis while minimizing production differences between the parent breeds.
There are a lot of different ways to be a profitable dairyman, and producers have varying genetic goals. Bottom line – a dairyman should choose his approach wisely. Selection of a service sire is a long-term investment affecting more than one generation of cows in the herd. Crossbreeding has some short-term advantages and disadvantages. To date, it has not proven to be the magic pill to improve cow profitability for all dairymen. Remember, offspring are limited by the combined genetic potential of both parents. Long-term generational effects of crossbreeding in dairy cattle are not well documented or understood. Whether choosing a Holstein sire or a sire of another dairy breed, selection should come primarily from high-ranking sires for Lifetime Net Merit to optimize farm profitability.