Alternatives to crossbreeding – Dr. Nate Zwald
I would like to start out by saying I appreciate being asked to respond to this discussion. Similar to Dr. Hansen, I am quite passionate about this topic, and also am confident that I have both the practical knowledge (being raised on the 600-cow Bomaz Farms in Wisconsin) and the academic knowledge and experience to provide a response to the points made.
I agree with many of the points made by Dr. Hansen about the ideal Holstein cow. Dairy Cattle Judging has been a huge part of my life, and is something that I am proud of my accomplishments in, however the conformation that is considered “ideal” is not the most “functional”. Part of this is cow size, and part of it is dairy strength being confused with angularity. Dr. Hansen has done a good job of explaining the reasons for a different “ideal”, because clearly the fertility and longevity of the Holstein can be improved, and I do not need to revisit those statements. We have good longevity information, and instead of telling the cows how they should look, we can make significantly more progress if we simply listen to the cows tell us how they need to look to be the most profitable and longest lasting! The moderate sized cows with shallow udders that are not extremely dairy last the longest – now we need to make sure this type of cow is rewarded in classification programs. Classification programs are useless if they are not an indicator of longevity, and currently only the linear traits, and their combination into UDC and FLC are the only indicators of longevity, while final score has almost no impact on overall longevity.
My solution to the problem varies substantially from Dr. Hansen”’’s solution of crossbreeding. Why do we need to crossbreed to change the Holstein cow? Over the last 50 years we have made Holsteins that are genetically capable of producing more than 8,000 lbs more milk per lactation than they were in 1960. We also have changed the way cows look substantially, so we have proven we can change the cow through genetics. We now know that our perception of the way cows should look had flaws and needs to be corrected. Do we need to crossbreed to do this? I don””t think that is the only answer. We can also create the correct “ideal” cow and strive to get there.
Furthermore, most people interested in crossbreeding are interested in improving the fertility and longevity of their herd. This is a message that I advocate to everyone – we must pay attention to PL and DPR in selection programs. We will be increasing the weight on these important characteristics by a combined 5 percentage points in the upcoming change to the TPI formula, which will reward those sires that have highly fertile, long lasting daughters. Furthermore, if a certain producer wants to put more or less weight on PL, DPR, SCS, or Daughter Stillbirth (DSB), they certainly can do that in their own breeding program.
The real question is, must we crossbreed to change the fertility and/or longevity within our breed (or within our herd), and the answer is absolutely not. Is crossbreeding one way to improve those important traits? Yes, but it will have negative effects on production. If we analyze the paper that Dr. Hansen refers to, we find that tables 4, 5, and 6 provide some very interesting information that cannot be forgotten in this discussion. The fact is that the pure Holsteins out produced both the Swedish Red X Holstein crosses and the Montbeliard X Holstein crosses by about 2,000 lbs of milk, 45 lbs of fat, and 40 lbs of protein per lactation! This is substantial! The equivalent is similar to using a Holstein sire that is -2000 PTAM, -45 PTAF, and -40 PTAP. Would any of you be willing to use a sire with these kinds of numbers?
To be fair, the study does state that only 61% of Holstein cows calved back in a second time within 17 months after first calving, while significantly larger numbers of crossbred cows calved back in (average 76%) in the same time frame. While this is an impressive difference, I have data from one of our Alta Advantage® herds with 1600 cows that shows daughters of high PL sires (n=116) return for a second lactation 78% of the time, while daughters of low PL sires (n=91) return for a second lactation only 52% of the time, therefore proving that effective sire selection for this trait can have even more impact in a single generation than crossbreeding.
Likewise, the study states that the days open of the Holstein cows is 14 days longer than the Scandinavian Red. Again an impressive difference that is equivalent to the expected difference from using a Holstein sire that is 3.5 for DPR. There are Holstein sires that are nearly this high, and again more “real world” data shows that within another Alta Advantage® dairy that 75 daughters by one of the highest DPR bulls in the breed – KCK Bardale Blastoff (DPR=3.0) – have an average of 26 less days open than the rest of the herd, again showing that as much or more progress can be made in this important trait in a single generation than what can be made through crossbreeding. Equally as impressive is that production was not sacrificed, as these daughters are producing as much as their contemporaries.
I””m passionate that we can change the Holstein breed effectively through proper sire selection WITHIN the breed. Focusing more on traits like PL, SCS, and DPR will help facilitate this change while not losing the production that is proven in the California trials. When these traits are accurately evaluated in progressive dairies, like those sires tested through the Alta Advantage® program, we can be confident in the evaluations. We can””t be scared of these relatively new traits that can help our breed – instead we need to embrace them and use them to our advantage!
Respectfully submitted,
Dr. Nate Zwald
Alta Genetics
