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Rediscover the Value of Crossbreeding

Dan Frobose - OSU Beef Marketing Specialist

I get two questions asked of me on a regular basis. “Dan, I really like the quality grade premiums that I am getting on my cattle, but we4 are just not getting the carcass yield and growth that we were getting when we fed colored cattle” and “Why do my colored cattle leave the yard heavier and 30 days sooner?”

I work with a group of feedlot operators that supply cattle for the Ohio Signature Beef (OSB) brand. Ohio Signature Beef cattle are choice, all natural cattle that are raised in Ohio. Calves are pooled from farms here in the eastern cornbelt and finished on high grain

diets. Our producers get a nice premium for quality grade, however we still need to keep in mind that pounds pay the bills.

The past 20 years we have heard the message loud and clear that we need to select for birth weight and milk. As a result, many cow/calf producers have created herds that are primarily Angus on the cow side and are breeding them back to Angus bulls. The offspring carry

genes

that work

well

in those two

traits

along

with

marbling.

However,

in

most

cases

milk

and

muscle

are

negatively

correlated.

As feedlot operators, our goals

are to get optimum gains, efficient conversions, high carcass yields and a quality grade on choice or higher. The best tool available for helping to accomplish this goal seems to have become lost for the last several years. That, tool is Crossbreeding. Crossbreeding beef cattle offers two primary advantages relative to the use of only one breed:

A. Crossbred animals exhibit heterosis (hybrid vigor).

B. Crossbred animals combine the strengths of the various breeds used to form the cross.

Heterosis simply refers to the advantage in performance of the

crossbred animals as compared to the average of the straightbred parents.

Here’s an example to help you follow the advantages of heterosis:

The average weaning weights of

straightbred calves was 450 pounds for breed A and 535 pounds for breed B, so the average of the straightbred parents is 492 pounds. If we cross the two breeds, the calves avertage weaning weight is 525 pounds, heterosis would be calculated as (525-492) x 100=6.7%. This 6.7% increase or 38 pounds is the resulting heterosis.

Dr. Scott Grenier, from VA Tech provides the following explanation:

The amount of heterosis expressed for a given trait is inversely related to the heritability of the trait. Heritability is the proportion of the measurable differnce observed tetween animals for a given trait that is due to genetics (and can be passed to the next generation). Reproductive traits are generally low in heritability (less than 10%), and therefore respond very slowly to selection pressure since a very small percentage of the difference observed between animals is due to genetic differences (a large proportion is due to environmental factors). The amount of heterosis

is largest for these tgraits that have low heritabilities. This has significance for commercial breeding systems, as crossbreeding can be used to enhance reproductive effieiency. To date, the ability to select for reproduction is limited (ie. There are no EPDs for reproduction). Traits that are moderate in their heritabilities (20 to 30%) such as growth rate are also moderate in the degree of heterosis expressed (around 5%). Highly heritable traits (30 to 50%) such as carcass traits exhibit the lowest levels of heterosis.

Traits

Units

%

Calving rate, %

3.2

4.4

Survival to Weaning, %

1.4

1.9

Birth Weight, lb.

1.7

2.4

Weaning Weight, lb.

16.3

3.9

ADG, LB./d

.08

2.6

Yearling Weight, lb.

29.1

3.8

INDIVIDUAL HETEROSIS

: Advantage

of the Crossbred Calf

Traits

Units

%

Calving rate, %

3.5

3.7

Survival to Weaning, %

.8

1.5

Birth Weight, lb.

1.6

1.8

Weaning Weight, lb.

18.0

3.9

Longevity, yr.

1.36

16.2

MATERNAL HETEROSIS:

Advantage of the Crossbred Cow

Cow Lifetime Production No. Calves Cumulative Wean. Wt., lb.

.97

17.0

600

25.3

Adapted from Cundiff and Gregory, 1999

The other important advantage to crossbreeding is the ability to take advantage of the strengths of two or more breeds to produce offspring that have optimjum levels of performance in several traits. As example, British breeds generally excel in marbling potential whereas Continental breeds typically are superior for red meat yield (cutability). Combining the breed types results in offspring that have desirable levels of both quality

grade (yield

(marbling) and retail

grade).

Similarly,

yield milk

production and growth rate may be most effectively optimized by crossing two or more breeds. The result of this crossbreeding is reflected in higher valued feeder/fat cattle. Maternal heterosis is often the forgotten factor of crossbreeding system. Remember reproduction and conception is the start of achieving premiums. An open cow isn’t profitable to anybody in the beef industry.

In short, a well-designed corssbreeding program can improve the productivity of the

commercial cow-calf operation. Through the benefits of heterosis, crossbreeding may effectively improve the most economically important tgraits to the beef enterprise-reproduction and growth. Additionally by combining the attributes of the various breeds available, crossbreeding programs allow for the matching of genetics with the environment, feed resources, and end product specifications.

Different levels of heterosis can be achieved by the number of

breeds that are involved. Good recordkeeping is a must to assure that your cowherd is achieving the sedired results that come with an effective crossbreeding system. Work closely with your seedstock producer in selecting the purebred or composite bulls that are needed to reach your desired goals. Study the EPDs that are provided and keep a balanced objective for all the traits that effect the bottom line for your herd and for the feedlot operations who are finishing out your cattle.

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