Demo Jersey Calves

Hello, and welcome to the Colostrum Monte Carlo Knowledge Base.

In this CMC demo, we’ll take a look at how to incorporate multiple breeds, or more generally, two different calf populations, into a simulation. So, let’s get started.

Assuming that you already have CMC running, go to the Equations menu on the menu bar at the top of the screen. Click Equations, and then select AEA Adjustments.

Here, you’ll see three different sections that allow us to adjust the simulation. One of these is Breed.

By checking the box and entering the percentage of the herd represented by Jerseys, or by another group of calves, we can tell CMC to include two different calf populations in the simulation.

For this example, I’ll select Use to Adjust Birth Weight and enter 50 percent of the herd as Jerseys. Then I’ll click OK.

Now, notice that the calf information table contains a second row for birth body weight. This second population could represent Jersey calves, Holstein-Angus crosses, or another group of calves with a different birth-weight distribution.

It’s important to understand that CMC does not calculate AEA differently for Holsteins and Jerseys. The breed option is simply a way to include two different calf populations in the simulation, each with its own birth-weight distribution, mean, and standard deviation.

The default values for Jerseys are a mean birth weight of 27.5 kilograms and a standard deviation of 3.5 kilograms. We’ll use those values and assume a normal distribution.

With 10,000 iterations selected, we’ll click Run.

Now, let’s look at the results.

The average body weight of our simulated calf population is 34.3 kilograms, with a standard deviation of 7.9 kilograms. The 5th and 95th percentiles are 23.1 and 47.2 kilograms. As expected, including two different populations creates considerably more variation in birth weight.

If we select the Body Weight row in the Monte Carlo Results table, the input distribution chart at the lower right shows two distinct distributions. One is centered at about 28 kilograms, representing the Jersey population, and the other is centered between about 40 and 42 kilograms, representing the Holstein population.

On the left, under Herd Information, we can also see that of the 10,000 calves simulated, 4,970 were assigned to the Jersey population. Because this is a Monte Carlo simulation, the exact number will vary slightly from one run to another.

In this way, CMC allows us to represent two different calf populations within the same herd. Differences in birth weight affect estimated plasma volume and, ultimately, the predicted serum IgG concentration.

That’ll do it for this demonstration. Be sure to visit the other CMC Knowledge Base articles to learn more about getting the most from Colostrum Monte Carlo.

Thanks for watching.