Crossbreeding dairy cows to improve sustainability
The ideal dairy cow should:
- Produce high fat and protein.
- Produce a calf regularly without any trouble.
- Maintain superior fertility.
- Have functional udder, feet and legs.
- Be resistant to health problems and mastitis.
If a cow has these traits, she should have a long productive life. Trouble-free cows are often unrecognized by producers because they are never in the sick pen.
The University of Minnesota researches crossbreeding in dairy cattle and explores alternative ways for producers to improve calving ease, fertility, health and survival of cows.
When compared to purebred Holsteins, studies have found that crossbreds are superior for fertility, survival and productive life. However, we need high quality purebreds to have high quality crossbreds.
The use of a specific breed depends on each producer's management system, but regardless of breeds, the ideal dairy cow should have a good productive life if she has high fat and protein, excellent fertility and the ability to produce a calf regularly, functional udder, feet and legs, and low prevalence of health problems.
Sustainability and profitability need to be highly considered. To achieve this, the future ideal dairy cow will also need to have a smaller body size and more efficient conversion of feed to milk.
Crossbreeding has been applied in other species such as swine and poultry to increase vigor. In these species, improvements have been made to decrease mortality and increase feed efficiency and meat and carcass quality traits to improve overall profitability.
Sires of higher genetic merit retain the best traits of the parent breeds. In dairy cattle, breeding Holstein heifers and cows to Jersey bulls has been a popular method of crossbreeding in the U.S. and makes up a high percentage of the current population of lactating crossbreds.
Geneticists at the University of Minnesota have been crossbreeding with Montbéliarde and Viking Red sires at the University’s two dairy research herds since the early 2000s.
The first dairy herd is located on the U's St. Paul campus where 110 milking cows are maintained in a tie-stall barn and compost bedded pack barn year round. This herd consists of purebred Holsteins and ProCROSS crossbreds.
Procross is a three-breed rotational mating system using the Montbeliarde, Viking Red and Holstein breeds. Frozen semen of A.I. bulls from the three breeds is used in rotation for generations with ProCROSS© and the mating system is simple and tidy without concerns about the inbreeding of embryos or calves.
The second dairy is located in Morris, Minnesota at the West Central Research and Outreach Center. There are 150 organic cows and 150 low-input conventional cows.
Both herds include purebred Holsteins, ProCROSS crossbreds and a three-breed cross of Normande x Jersey x Viking Red.
- During the summer grazing season (May to October) organic cows are on pasture and supplemented daily with six pounds of corn per cow, and low-input cows are fed a total mixed ration in an outdoor confinement dry-lot.
- During the winter season (November to April) all cows were fed a total mixed ration consisting of corn silage, alfalfa haylage, corn, soybean meal and minerals in an outwintering lot and a compost barn.
- Because cattle in this herd consume pasture, Normande and Jersey breeds are utilized in this herd, but not in the St. Paul herd. Normande and Jersey cattle can consume forages and still produce adequate amounts of milk with high fat and protein.
114 purebred Holstein cows, 248 ProCross crossbreds, and 167 Normande x Jersey x Viking Red crossbreds from the Morris herd were evaluated for total average rumination time.
- HR-LD tags were used to record rumination time in total minutes per day.
- Similar rumination time was reported for all breed groups evaluated:
- Purebred Holsteins: 521 minutes per day
- Procross: 513 minutes per day
- Normande x Jersey x Viking Red: 513 minutes per day
Future projects to keep an eye out for include creating genomic predictions for crossbreds, determining the most profitable crossbred for grazing in the Midwest, and lactation curves of purebred Holsteins compared to crossbreds.
St. Paul herd research
123 first-lactation cows (63 ProCROSS© and 60 Holstein) and 80 second-lactation and third-lactation cows (43 ProCROSS© and 37 Holstein) were compared for dry matter intake, body weight, wither height, body condition score, milk volume and fat plus protein production over a three-year period.
All cows were fed the same total mixed ration twice daily in tie-stalls with partitions in the manger. Feed samples were collected twice weekly to determine dry matter content. Feed intakes were recorded only from days 4 to 150 of lactations. During the same lactational period, body weight, height and body condition score were recorded for each cow.
Fat plus protein production (lb) wasn’t different for the two genetic groups during first lactation or during second and later lactations. However, the ProCROSS© cows had higher percentages of fat and protein in their milk than the Holstein cows and, for most milk markets, milk is priced based mainly on the solids in milk and not on the fluid carrier of milk.
Fat plus protein production per pound is a better predictor of the value of milk that is milk volume per pound. The milk volume, which is mostly water, was lower for the ProCROSS© cows than the Holstein cows. However, despite equal fat plus protein production, the ProCROSS© cows had significantly lower dry matter intake than their Holstein herd mates, and the difference was 312 pounds less dry matter intake (-4.8 percent) during the 147-day study period in first lactation and 512 pounds less dry matter intake (-6.5 percent) in second and third lactations.
How were the ProCROSS© cows different from the Holstein cows?
Other than the lower feed intake with equivalent fat plus protein production, they had shorter height at the withers, carried significantly more body condition, but were not different from the Holstein cows for body weight. Smaller frame sizes of cows and more body condition of cows to enhance fertility and health should be advantages of ProCROSS© cows over Holstein cows for commercial dairying. Other studies with much larger numbers of cows have documented ProCROSS© cows have higher pregnancy rates (fewer days open and higher conception rates), reduced health treatment costs and longer herd life.
Alternative feed efficiency evaluation measures
Fat plus protein production divided by dry matter intake.
Energy-corrected milk divided by dry matter intake.
Dry matter intake divided by body weight.
Residual feed intake (which is currently used for genetic evaluation of dairy cattle).
For all four of these measures, the ProCROSS© cows were significantly more feed efficient than the Holstein cows. All of these measures of feed efficiency are defined in a very narrow sense relative to economic gain, because differences in fertility (which influences how soon cows return to peak production with a subsequent lactation), health treatment costs, and herd life of cows are ignored. Based on this research, improved feed efficiency can be added to the list of advantages of ProCROSS© cows over Holstein cows.
Reviewed in 2019