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Listed below are some of the more commonly performed reproductive surgeries. The notes are a compilation of some of the techniques that the authors use and are not intended as an exhausting, heavily referenced treatise of all available techniques. No attempt has been made to discuss all reproductive techniques or conditions requiring intervention.
In cyclic mares, the uterine environment can easily disturbed due to inflammatory processes that occur secondary to microbial invasion. Different aerobic and anaerobic bacteria can enter the uterus during natural mating, artificial insemination, reproductive examination or parturition. The postpartum period is a critical phase since due to relaxation of the uterus and cervix may favor recurrent infections air intake pneumovagina or urine collection in mares with poor perineal conformation.
The mucus formed in the equine cervix during pregnancy cervical mucus plug — CMP is believed to play a critical role as a barrier to microbial entry into the pregnant uterus. The CMP may provide an additional physical and physiological barrier protecting the uterus from infiltration of bacteria during pregnancy Lee et al. In women, the CMP has been shown to be important in both the adaptive and innate immune systems. The CMP is able to inhibit a wide range of both gram-negative and gram-positive bacteria in vitroincluding Streptococcus spp.
Many responsible stallion owners require a "clean uterine culture" from a mare prior to breeding her live cover or shipping semen. The results of an endometrial swab culture alone are not a reliable indicator of uterine pathogenicity since it may reflect contamination of the sample. A cytology smear of the sample can be taken in conjunction with the culture to identify mares with active infection increased inflammatory cells: neutrophils, lymphocytes, plasma cells, eosinophils, macrophages, and mast cells.
People who have bred many mares soon realize that each mare is an individual and there may be many variations in the reproductive cycle length between mares. There is, however, a basic cyclic pattern that "most" mares will follow. Typically, during the breeding season, a mare will have a day estrous cycle the interval from one ovulation to the next.
Most non-pregnant mares pass into anoestrus a non-cycling stage during winter at which time they cannot become pregnant. Many of these factors can be manipulated to encourage the mare to become reproductively active at non-favourable times of the year. This is particularly important when carrying out artificial insemination and embryo transfer.
Three mares were treated for vaginal evisceration of a portion of the small intestine. Evisceration occurred in 2 mares shortly after breeding accidents in which the stallion's penis penetrated the vaginal fornix dorsal to the cervix. The affected bowel was replaced through the laceration, and the vaginal defects were sutured with the mares standing, utilizing epidural anesthesia. One mare recovered without complications, was subsequently bred, and delivered a foal with no difficulty.
Foaling injuries involving the vestibulum and vulvar lips are fairly common, especially in maiden mares where the tissues are less distensible than in older animals. The injuries sustained by these mares usually occur when the front hooves of the foal penetrate the dorsal vaginal wall during the second stage of parturition. This is most common when the foal is in a foot-nape posture as shown below.
Horse breeding is reproduction in horsesand particularly the human-directed process of selective breeding of animals, particularly purebred horses of a given breed. Planned matings can be used to produce specifically desired characteristics in domesticated horses. Furthermore, modern breeding management and technologies can increase the rate of conception, a healthy pregnancy, and successful foaling. The male parent of a horse, a stallionis commonly known as the sire and the female parent, the mareis called the dam.