Page 47 - New Mexico Horse Breeders 2019 Stallion Register

The cytology provides an up close and personal look at the uterine environment and can identify problems that may not be identified otherwise. To create a cytology the culture swab is rolled onto a microscope slide, the slide is stained to highlight red and white blood cells and bacteria, and then the slide is viewed under a microscope.
a culture is of paramount importance. To perform a uterine culture, the mare’s tail is wrapped and her perineum cleaned well. The guarded culture swab is then introduced as cleanly as possible through the cervix and into the uterus itself. This can be accomplished if the mare is out of heat, however more useful information is gained if she is in heat, as the cervix is open and thus potentially more prone to infection. The culture can be then sent
off or plated and read in house. If bacterial colonies are grown, an antibiotic sensitivity test should be performed. The purpose of the sensitivity test is to determine the appropriate uterine antibiotic treatment which eliminates the “shotgun” therapy approach. The so-called shotgun approach involves use of multiple antibiotics to blindly treat the uterus. This approach is rarely effective and can be very detrimental in the long run as it predisposes the mare to developing both resistant bacterial infections and/or yeast. While maiden mares typically do not necessitate a culture, maiden mares bred through 2 estrous cycles without conception should be cultured.
An incredibly valuable, and often under- performed test that can be procured with
the culture is uterine cytology. The cytology provides an up close and personal look at the uterine environment and can identify prob- lems that may not be identified otherwise. To create a cytology the culture swab is rolled onto a microscope slide, the slide is stained
to highlight red and white blood cells and bacteria, and then the slide is viewed under a microscope. It is not uncommon to identify significant amounts of white blood cells and bacteria on a cytology and have no growth
on the corresponding culture. Conversely, if bacterial colonies form on the culture media, the cytology helps characterize the significance of the bacterial growth. If there is bacterial
growth without corresponding presence of white blood cells, it can be concluded that the bacteria grown on the plate is likely due to con- tamination. If a culture fails to grow bacterial colonies, but the cytology identifies bacteria and white blood cells, treatment still should be implemented. If we were to rely on the culture alone, we could miss treating a dirty mare, or miss addressing those more subtle problems that can also affect fertility.
Depending on the history and number of years a mare has been open, a uterine biopsy should be considered. The biopsy provides information about the degree of scarring and inflammation in the uterus as well as infec- tion. The lab the biopsy is sent to will grade the biopsy which gives a range of the likelihood a mare will get in foal and carry to term. This information can be hugely helpful in the prepa- ration process of a “problem” mare. Depending on the grade of the biopsy the decision can be made prior to breeding season how aggressive treatment needs to be and if treatment will likely result in a live foal.
So you’ve done all this work in the fall to get your mare ready for the breeding season, but we are still months away from her coming into heat naturally. To “trick” the mare’s body into coming into heat in February versus mid to late spring, a lighting program should be implemented. The days are short in the fall, and mares are long day breeders by nature,
so we need the mare’s brain to think spring
is starting when it’s still mid fall. Starting in mid-November the mare should be provided 16 hours of light, both normal daylight, and artificial light to prolong the perception of daylight. The artificial lighting program needs to be continued for 60 days, which
places us squarely in the middle of February, and breeding season.
Chemical manipulation, in the form of progesterone and estradiol, can also be started in the weeks prior to the breeding shed opening. This chemical manipulation works in tandem with the lighting program and allows the veteri- narian and breeding staff to take over control of the timing of the estrous cycle and consequently reliably dictate when the mare will ovulate
for the first time that breeding season. This tends to be a more important necessity for our Quarter Horse performance mares as shipped semen is the most common breeding method, however for our Thoroughbred mares booked to high demand stallions, we may only have 1 day available to take her to the breeding shed. Knowing precisely when the mare’s estrous cycle will start for the breeding season makes setting up these shed appointments much simpler and certainly increases the likelihood of that desired early pregnancy.
Unfortunately, even following this protocol is still no guarantee of success. As I remind my clients (and Bryan and myself with our own mares) the swimmers still have to get to the egg, and fertilization still has to occur, and realisti- cally we have VERY little control over that part of the process. Yet, in doing the leg work in the fall, and having our mares programmed via lighting and chemical manipulation, we give ourselves the greatest chance of getting the mare in foal early and thus having an early baby. Even if she doesn’t “take” on the first cover, we are still miles ahead of where we would be if we waited for her to come into heat on her own, get bred a few times, and then realize she has
a uterine infection or some other issue that is preventing her from conceiving.
To “trick” the mare’s body into coming into heat, a lighting program is typically used. The artificial lighting program needs to be continued for 60 days, which places us squarely in the middle of February, and breeding season.
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