STALLION MANAGEMENT

Lesson Twelve

Breeding Farm Stallion Record Keeping

 

          In this lesson you will review a variety of record keeping techniques that have been proven to greatly increase the effectiveness of breeding farm management. Good records can alert the management to possible problems that might otherwise be overlooked.

          A big part of the effectiveness of good breeding records is the ability and regular scheduling of record analysis.

          The following outline will serve as a study guide and overview of the important aspects of the most commonly kept records.

 

Permanent Records

1.  Individual Stallion Records

a.  Daily breeding reports – a must for all breeding facilities.

b.  Routine semen evaluations. This is done every other day on many artificial insemination farms, but may not be done often enough on a live cover operation. It is vital to be up to date on the semen quality of all your stallions during the breeding season.

c.  Routine veterinary medications or reports.

d.  Notes on stallion behavior.

 

2.  Stallion Service Reservation List

a.  Daily breeding report

 

Evaluation of Breeding Records

1.  Seasonal Pregnancy rate is the number of pregnant mares divided by the number of mares bred times 100 (the number of mares pregnant on a specific day divided by the number of individual mares bred to that date multiplied by 100 gives the correct percentage).

a.  For the farm, for the year or season

b.  To a certain date

c.  By types of mares

1. Barren

2. Foaling

3. Maiden

 

          Example: for the breeding season 2003 let’s say on July 30 it was determined that of the 20 individual mares bred during that season, 17 were found to be pregnant .

          The seasonal pregnancy rate as of July 30, 2003 is:  17 divided by 20 equals .85 x 100 = 85%

          If these same 20 mares were checked for pregnancy again on November 30 and 15 were found to be pregnant the seasonal pregnancy rate for the 2003 breeding season would change as of that date to: seasonal pregnancy rate as of November 30, 2003 is: 15/20 =.75 x 100 = 75%

          The abortion rate from July 30 to November 30 would be figured as:  2 divided by 17 = .117X100 =11.7%

 

2. Cycles /pregnancy is found by the total number of cycles divided by the total number of pregnant mares. This calculation is a very important indication of the fertility or efficiency of the individual stallion.

          Example: if on April 5, it is determined that a single stallion was bred to 25 mares to that date that have been called “in foal”, and of those 25 mares, 20 conceived after only one cycle, 3 conceived after having been bred through 2 cycles, and 2 conceived after having to be bred through 3 cycles, then divide the number of  total cycles it took to get these 25 mares in foal---- (20x1) + (3x2) + (2x3) = 32 total cycles divided by the total number of mares in foal (25); or 32/25 = 1.28 cycles per pregnancy.

 

 

3. Pregnancy rate per cycle shows what percentage of mares became pregnant after the first estrous cycle, after the second, after the third when bred for the season to a particular stallion,

          Example: at the end of a breeding season it was determined the stallion bred 30 mares, of which 10 became pregnant on their first cycle, and it took two breeding cycles for 10 more to get pregnant.  Five mares became pregnant after being bred over 3 cycles, and the final 5 mares required 4 cycles before becoming pregnant.  For that stallion then the pregnancy rate for this group of mares, after the first cycle was 10/30 = .33x100 = 33%

          The pregnancy rate for this group of mares after the second cycle was 10/30 = .33x100 = 33%

          The pregnancy rate for this group of mares after the third cycle was 5/30 =  .165x100 = 16.5%

          And the pregnancy rate for this group of mares after the 4th cycle was also 16.5%

          Since this group of mares was bred to only one stallion, then these figures would be valid for evaluating this stallion in regards to his fertility if we considered these to be average mares.

          If a second stallion had been bred to 30 different mares during the same season and it was determined that after the first cycle 20 of these mares had become pregnant, and after the second cycle 9 mares were found to be pregnant, and the 30th mare was bred 4 more cycles and stayed barren through the entire season, then:

          The pregnancy rate for this group of mares after the first cycle was 20/30 =  67x100 = 67%

          The pregnancy rate for this group of mares after the second cycle was 9/30 = .30x100 = 30%.

          So in the case of the second stallion, his fertility appears to be much superior to the first stallion.  It could be concluded that the second stallion could handle a much larger book of mares per season than the first stallion.

 

4. Foaling rate –The percent of mating that produces a live foal is determined by dividing the number of live foals by the number of mares bred the previous season. This can be figured for a particular stallion or an entire operation, and is usually figured both ways. Foaling rate provides an overall ratio of efficiency, but it does not determine what most influenced the overall ratio. More specific ratios, such as pregnancy loss rate, embryo loss rate, fetal loss rate and stillbirth fetal loss rate, can be used to identify differences at specific times of gestation.

 

 

Effects of Breeding Frequency on Stallion Fertility

          This parameter is very individualistic. Some stallions are more fertile than others

          The pregnancy rate per cycle can be helpful in determining stallion fertility, but you cannot determine a stallion’s individual threshold at which breeding efficiency declines without analyzing the records closely. This is important information to be able to predict the overall fertility of a particular stallion and his breeding potential. (How many mares to book to this stallion for good success).

          Effects of breeding frequency is determined by the number of mares bred in one week compared to the percentage of mares bred during that week that were pronounced in foal at 14 to 18 days after that breeding. When this rate begins to decline, the stallion has begun to reach his threshold of mares that can be bred to that particular stallion and still expect good pregnancy rates.

          Any number of mares over that amount would cause a lowering of that stallion’s sperm output and his pregnancy rate would go down. This is very important to a Thoroughbred farm where A. I. is not allowed.

 

ASSIGNMENT (No Quiz)

          Please answer each question as completely as possible. Resources other than the written text are encouraged as well as personal experiences. Please site your resources – include the link if you used the internet; book title and author if you used hard copy.

          Send your report to Dr. Sales at    jsales@horsecoursesonline.com

          Include your full name and email address on the document. 

 

1. What breeding farm records can be helpful in determining or keeping track of the overall health, well being, and breeding efficiency of the individual breeding stallion?

 

2.  Math Questions:

Stallion’s breeding record

Total # of maiden mares bred in season – 8   Total # of maiden mares in foal - 6

Total # of barren mares bred in season – 18   Total # of Barren mares in foal – 12

Total # of foaling mares bred in season – 40   Total # of foaling mare that got back in foal – 38

 

Based on the above record, report:

1.       What was the seasonal pregnancy rate for the maiden group of mares _________.

2.       What was the seasonal pregnancy rate for the barren group of mares ______.

3.       What was the seasonal pregnancy rate for the group of foaling mares _______.

4.       What was the overall seasonal pregnancy rate for the stallion    _____________.

5.       If the maiden mares that became pregnant were bred a total of 9 cycles, what was the cycle per pregnancy. _________