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 jacksales1234@gmail.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. _________
Last Question: Did you think this
course was worthwhile? How would you
suggest that this course be improved or changed for the better? Thank you for
your input. Dr. Sales