The School Science Fair

It's important to expand your knowledge about your 4-H projects.  I killed two birds with one stone by using my own dairy animals as subjects in my research and observations for the school science fair.

I did a short field study on the effects of temperature on how fast a dairy heifer eats.

Then I also did some research to see what formal studies have been done on the subject.  WOW!  I found some that backed up my hypothesis!

Here's most of the formal stuff:

ABSTRACT

This experiment was performed to determine how temperature affected the rate at which a dairy heifer ate.  The hypothesis was that the hotter the temperature, the slower the animal would eat. 

Formal research has shown that when a dairy animal experiences  temperatures above 25 degrees Celsius (77 degrees Fahrenheit) voluntary feeding decreases (Wadsworth).  Other published research shows that when a dairy animal’s body  temperature goes up, milk production goes down (Johnson).  This same reaction to heat can be seen at livestock shows and fairs where dairy animals are on display (Jennings, A.).       

The procedure included selecting a two year old Holstein dairy heifer from the herd for observation.  She was fed two gallons of a custom mixed, high protein dairy grain daily while chained at her feed trough.  The length of time and the air temperature were recorded.  The colder the air temperature, the faster the animal ate. 

INTRODUCTION

This study “Food: Hot/Cold” focuses on the effects of temperature on the grain consumption rate of a dairy heifer.  Grain is an important part of a heifer’s daily diet.  Grain contains protein which helps the body to grow.  The custom high protein dairy mixture consists of corn, rolled oats and barley pellets, soybean meal, cottonseed hulls, limestone, and possibly molasses and trace minerals.

Like all food, this grain mixture has a certain amount of vitamins and minerals.  Healthy food helps ensure a healthy animal.  Healthy dairy animals produce healthy milk after they have calved.  Grain is an important part of a dairy animal’s diet to get them in the best condition possible to be good milk producers.  It is cheaper to take care of one cow that can make a lot of milk than to take care of two cows that produce a little milk.  

If If milk production can be speeded up by lowering the air temperature, then milk could be produced faster and cheaper.  If milk is produced cheaper, the savings will show in the price people have to pay for milk at the store.   

PROBLEM STATEMENT

Will temperature affect how quickly a dairy heifer eats?

HYPOTHESIS

I hypothesize that the hotter the temperature, the slower the heifer will eat.  That means that the opposite is true, the cooler the temperature, the faster the animal will eat.

MATERIALS

A dairy heifer

A nylon halter with a ring to attach a chain

A chain attached to the animal’s pen

A bucket

2 gallons of high protein dairy mix grain feed

A cell phone with a stopwatch timer option

A built-in thermometer in the truck

An assistant to start the stopwatch

Paper / pencil to record data 

PROCEDURE

1.    A two year old Holstein dairy heifer was chosen from the herd.

2.    The heifer was fitted with a nylon halter in order to     limit her movements while eating.

3.    A chain was attached to the pen panel and hooked     onto the nylon halter just before feeding time (as     shown to me by Miss Jennings, my 4-H leader).

4.    Two gallons of custom mixed high protein grain was     measured out and held in a bucket until poured into     the heifer’s feed trough.

5.    The assistant started the stopwatch timer at the     moment the grain was poured.

6.    The air temperature was recorded from the readout     on the dashboard of the truck.

7.    The heifer was observed while eating. 

8.    When the animal backed away from the trough, the     trough was inspected for any remaining grain.

9.    When the grain dust (finely ground meal) was all     licked clean, the timer was stopped, the time was     recorded, and the animal was released from the     chain.

DATA

On day one, the temperature was 76 degrees.  It took 24:35 for the heifer to complete her serving of grain.  On day two, the temperature was 82 degrees.  It took 29:18 to complete the serving.  Day three was 75 degrees, and it took 21:18 to finish the grain.  On day four the it 52 degrees.  It took 15:29 for the heifer to eat.  On day five it was 57 degrees and it took 17:44 to completely finish the two gallon portion of grain.

SUMMARY

The data collected demonstrates that when the temperature goes up, she eats slower.  When the temperature goes down, she eats faster.  (See Chart 1)

 

 (Chart 1)

CONCLUSION

As stated in my hypothesis, I believe that the higher the temperature, the slower a dairy animal will eat, and that the lower the temperature, the faster a dairy animal will eat.  The experimental data that was collected supported my hypothesis, indicating a direct relation between temperature and rate of grain consumption.  The warmer the temperature, the slower my research subject ate.  The cooler the temperature, the faster my subject ate.  The experiment confirmed that temperature slows or speeds the rate at which a dairy animal eats.

Through my research and my experience, I discovered that in addition to the temperature, the type of weather also fluctuated.  I experienced days that were sunny, cloudy, still, windy, and even a day of light mist.  An idea for a future experiment would be to also note weather conditions in addition to temperature.

BIBLIOGRAPHY...