Equine Reproduction Laboratory, Colorado State University, USA
Introduction
Antisperm antibodies (ASAs) have been suggested to be a cause of infertility in both males and females of a number of species, including mice, rabbits, cattle, horses, humans, and other species. IgG, IgA, and IgM antibodies directed against sperm antigens have been detected in various fluids and tissues.
Published studies have reported that 13–77% of women with unexplained infertility have ASAs detected in their serum. Mechanical or chemical disruption of the mucosal layer of the female genital tract has been proposed as the mechanism by which exposure to the “foreign” sperm antigen occurs. An immune response subsequently develops following exposure to sperm antigens.
Potential mechanisms by which ASAs may adversely affect fertility in the female of various species include:
Prevention of sperm from undergoing capacitation.
Prevention of sperm binding to the oocyte.
Prevention of sperm from undergoing the acrosome reaction.
Prevention of sperm from penetration of the zona pellucida.
Interference with early embryonic development.
Interference with maintenance of the pregnancy.
Technique
Assays for ASAs in various species include immunobead assays, mixed antiglobulin reaction tests, enzyme‐linked immunosorbant assays, immunofluorescence tests, tube‐slide agglutination tests, tray agglutination tests, flow cytometry, and radiolabeled agglutination tests. Pitfalls and false‐positive results have apparently been associated with all of the diagnostic tests for ASAs.
There are currently no diagnostic laboratories offering tests to determine the presence or absence of ASAs in equine serum or seminal plasma.
Additional Comments
In the horse, two case reports have associated the presence of ASAs in subfertile stallions that experienced testicular trauma. One study evaluated the prevalence of ASAs in a population of mares and reported that 10.2% of horses had ASAs in their serum. A pair of studies evaluated the immune response of mares actively immunized against stallion sperm cells. The authors concluded that IgG antibodies, and to a lesser extent IgA antibodies, against sperm cells increased following immunization, but there was no apparent decrease in fertility. A recent study reported that the percentage of IgG antibody bound spermatozoa were higher in non‐satisfactory breeder stallions than in satisfactory breeder stallions.
Clearly, additional studies are needed to determine the incidence of ASAs in mares with a history of subfertility or infertility. Furthermore, the relationship (if any) between the presence of ASAs and failure to conceive or failure to remain pregnant needs further investigation.
Further Reading
1 Day MJ. 1996. Detection of equine antisperm antibodies by indirect immunofluorescence and the tube‐slide agglutination test. Eq Vet J 28: 494–6.
2 Ferrer MS, George A, Miller LMJ, et al. 2014. Diagnosis of sperm‐bound anti‐sperm antibodies by flow cytometry and their association with semen quality. J Eq Vet Sci 34: 57.
3 Lee C, Nie GJ, Joo HS, Momont H. 1993. An enzyme‐linked immunosorbent assay (ELISA) for the detection of antisperm antibodies in horse serum. Theriogenology 40: 1117–26.
4 Mazumdar S, Levine AS. 1998. Antisperm antibodies: etiology, pathogenesis, diagnosis, and treatment. Fertil Steril 70: 799–810.
5 Nie GJ, Lee C, Momont HW, Joo HS. 1993. Equine antisperm antibodies (EASA): preliminary study of the clinical response following breeding in immunized mares. Theriogenology 40: 1107–16.
6 Papa FO, Alvarenga MA, Lopes MD, Campos Filho EP. 1990. Infertility of autoimmune origin in a stallion. Eq Vet J 22: 145–6.
7 Risvanli A, Cetin H, Apaydin AM, Kkorkmaz O, Atli MO, Timurkan H. 2005. Prevalence of anti‐sperm antibodies in mares in the south‐eastern Anatolian of Turkey. Bull Vet Inst Pulawy 49: 45–8.
8 Zhang J, Ricketts SW, Tanner SJ. 1990. Antisperm antibodies in the semen of a stallion following testicular trauma. Eq Vet J 22: 138‐41.
27 Starch Granule Test for the Evaluation of Oviductal Patency
Sofie Sitters1 and John J. Dascanio2
1 Amsterdam, The Netherlands
2 School of Veterinary Medicine, Texas Tech University, USA
Introduction
The oviduct plays a critical role during fertilization and early embryonic development. Consequently, pathologic conditions of the oviduct such as salpingitis, hydrosalpinx, and occlusion can adversely affect fertility of mares.
Blockage of the oviducts by masses of collagen, fibroblast cells, and other cellular and non‐cellular debris has been described. These oviductal masses can become a physical obstruction to both the upward passage of sperm and the downward passage of an embryo after fertilization. Diagnosis, however, of a blocked oviduct may be difficult and is sometimes suspected after exclusion of other possibilities for infertility in a mare.
This chapter describes the starch granule test for the diagnosis of oviductal patency. The starch granule test involves the deposition of a starch suspension onto the ovarian surface (through a transabdominal approach with a long needle) and the subsequent recovery of starch from the uterus or cervix. One oviduct can be tested at a time.
Equipment and Supplies
Surgical scrub, clippers, sterile soluble starch powder (1 g), sterile water (10 ml), sterile saline, 2% lidocaine, 2% Lugol’s iodine, microscope slides, coverslips, microscope, 14 gauge 5 cm (2 inch) needle, 18 gauge 12.5 cm (5 inch) spinal needle, syringes, obstetrical sleeve, obstetrical lubricant, sterile lavage tubing (optional).
Technique
The mare should be in diestrus for the procedure. Estrual mares may have a delay in oviductal transport.
A suspension of starch granules is made by mixing 1 g of sterile soluble starch powder in 10 ml of sterile water.
The flank of the mare is clipped and a sterile prep performed.
5 ml of 2% lidocaine is infiltrated subcutaneously and into deeper muscle layers in the flank area corresponding to the needle puncture for starch deposition.
As an optional procedure, one can create a puncture hole through the skin with either a small scalpel blade or a 14 gauge needle.
The ovary is held per rectum against the ipsilateral flank and a percutaneous needle puncture is made through the skin, or the previous puncture hole, with an 18 gauge 12.5 cm (5 inch) spinal needle to deposit 5 ml of starch solution on the ovarian surface.
The external cervical os and vagina are flushed with 10 ml of sterile saline beginning 24 hours after application of the starch solution (original description of the test). The fluid is recovered by aspiration back into the syringe.
Alternatively, the uterus of the mare could be lavaged with sterile saline through a catheter and inflatable cuff. The recovered fluid is allowed to sediment or is centrifuged.
An aliquot of the recovered fluid is placed