Nocardioform placentitis in a sample population of mares foaling in southeastern Pennsylvania and northeastern Maryland in 2020.

Nocardioform placentitis (NP) has been associated with mid to late pregnancy loss in mares. To date, disease outbreaks have been described only in central Kentucky, although sporadic, isolated cases have been reported globally. This study describes a series of cases of NP that occurred in a sample population of 299 mares foaling in southeastern Pennsylvania and northeastern Maryland in 2020. These cases coincided with an outbreak of NP that occurred in Kentucky that same year. On farms that reported information on both normal and abnormal foalings, nocardioform organisms/DNA were isolated from 6.3% of placental samples based on aerobic culture and/or PCR. In cases with characteristic gross lesions of the chorion, 41% of cases were positive on aerobic culture and/or PCR. NP was confirmed in 16 mares that had not resided in Kentucky for breeding or any part of gestation. Characteristics of mares confirmed positive for NP, including age, gestation length, and problems during gestation are described. Standardbred mares bred by artificial insemination were less likely to be affected than Thoroughbred mares bred by natural cover. Affected mares had prolonged Stage III labor compared with normal mares. These findings suggest that regional increases in NP may occur outside of Kentucky, potentially in parallel with Kentucky outbreaks.

Comparison of ticarcillin and piperacillin in Kenney's semen extender.

Ticarcillin and piperacillin were compared to determine their effect on sperm motility and bacterial growth of equine semen samples diluted in Kenney's glucose skim milk semen extender. Each ejaculate (n=11) was divided into three portions and glucose skim milk semen extender solution was added. The control semen extender solution contained extended semen and no antibiotic, whereas ticarcillin and piperacillin solutions contained extended semen plus 1.0mg/mL of ticarcillin or piperacillin, respectively. An aliquot was removed (1h after collection) to evaluate sperm motility and microbial concentration. All three solutions were stored at 4 degrees C and aliquots were obtained at 24 and 48 h to determine sperm motility and microbial concentration. Mean percentages of motile and progressively motile sperm did not differ significantly among control and antibiotic-containing solutions after storage. Control-extended semen samples from ejaculates of stallions (n=11) were contaminated with aerobic gram-positive and gram-negative bacteria. In solutions that contained either antibiotic, growth of these microbes was inhibited after 1, 24, and 48 h at 4 degrees C. Semen samples from stallions (n=5) were extended with Kenney's glucose skim milk extender containing no antibiotic, ticarcillin or piperacillin and then inoculated with approximately 5 x 10(2)CFU/mL Klebsiella pneumoniae or Pseudomonas aeruginosa; there was no significant difference between antibiotics in the inhibition of microbial growth. In conclusion, piperacillin was an appropriate alternative to ticarcillin in extenders for equine semen.

Retrospective study of dystocia in mares at a referral hospital.

REASONS FOR PERFORMING STUDY: The period between the onset of dystocia and its resolution has an important bearing on fetal outcome. There are few published data on which to base decisions regarding optimum management of cases in practice. OBJECTIVES: To evaluate and compare the effects of a coordinated dystocia management protocol (CDMP) with that of a previous protocol of random management on time to resolution and outcome in both an emergency dystocia referral population of mares (referred emergency cases: EM) and in a population of mares residing in hospital due to high risk pregnancy (HRP) concerns that then experience dystocia at parturition. METHODS: Retrospective study performed at a university hospital referral centre of cases presenting from 1991-2004 divided into Group 1 (pre-CDMP) and Group 2 (CDMP). RESULTS: Medical records of 71 cases with dystocia were retrieved and data recorded. For referred emergency cases (EM), time from hospital presentation to resolution decreased significantly by 32 min (P = 0.03) after institution of CDMP. Survival rate of mares at discharge was 86%. Survival of EM foals was low, with 10% in Group 1 and 13% in Group 2, surviving to discharge. For EM foals delivered alive, survival to discharge was 30% and 43% in Groups 1 and 2, respectively. Median Stage II was significantly (P < 0.001) different at 71 and 282 min for EM foals delivered alive vs. those not alive at delivery, respectively. Median duration of Stage II was also significantly (P < 0.001) different between EM foals surviving and not surviving to discharge, at 44 and 249 min, respectively. Survival of HRP dystocia foals to discharge was 79%. CONCLUSIONS: Although CDMP reduced the time from presentation at the hospital to resolution significantly for EM, total duration of Stage II for EM was unchanged, as was foal outcome. POTENTIAL RELEVANCE: Very early referral of mares with dystocia to referral centres with dystocia management protocols may improve fetal outcome as increased duration of Stage II in the horse affects fetal outcome negatively.

The impact of low-volume uterine lavage on endometrial biopsy classification.

In the mare, the low-volume uterine lavage technique allows for bacterial sampling of the entire uterine lumen and is usually performed after obtaining the traditional double-guarded endometrial swab for aerobic culture and cytology and before procurement of an endometrial biopsy sample during a breeding soundness examination. The purpose of this study was to explore the potential effects of the low-volume lavage on the endometrial biopsy classification and polymorphonuclear cell (PMNs) infiltration in the context of a breeding soundness examination. Fourteen light horse mares of mixed breed, age 7 to 21 years, with known reproductive history, were included in the study, matched by age and reproductive history, and then divided into treatment and control groups. Transrectal palpation and ultrasonography, endometrial swabbing, and the first endometrial biopsy were performed in all mares. Low-volume uterine lavage was performed in the treatment group but not the control group. After either the lavage or a 15-minute rest, a second endometrial biopsy was obtained from both the control and treatment groups. Endometrial swabs and effluent from the low-volume lavages were submitted for aerobic culture and sensitivity. Biopsy samples were fixed in Bouin's solution for 24 hours, processed, stained with hematoxylin and eosin, and then viewed under bright light microscopy. Additional staining with anti-neutrophil elastase antibody (ab68672) was performed for indirect immunohistochemistry. All samples were interpreted by a blinded observer. When the first (pre-uterine lavage) and second (post-uterine lavage) biopsies were compared using a mixed-effects logistic regression, there was no difference in endometrial biopsy classification (P = 0.74), presence of PMNs in blood vessels (P = 0.728), or infiltration of PMNs in the tissue (P = 0.934) between the treatment and control groups. In this study, the low-volume uterine lavage did not affect the endometrial biopsy classification.

Concentrations of arachidonate metabolites, steroids and histamine in preovulatory horse follicles after administration of human chorionic gonadotrophin and the effect of intrafollicular injection of indomethacin.

This study investigated the sequence of hormonal changes within the preovulatory follicles of mares. Mares were injected i.v. with 2500 IU human chorionic gonadotrophin (hCG) when a preovulatory follicle of 35 mm in diameter was detected. Fluid was aspirated from preovulatory follicles before (0 h), and 12, 24 and 36 h after administration of hCG. Concentrations of progesterone, prostaglandin (PG) E2, PGF, 6-keto-PGF1 alpha and thromboxane B2 in follicular fluid increased significantly (P less than 0.01) between 0 and 36 h. At 36 h, PGE2 was present in highest concentrations, followed by PGF and 6-keto-PGF1 alpha; thromboxane B2 was present at lower concentrations than other prostanoids. Concentrations of 13,14-dihydro-15-keto-PGF2 alpha increased significantly (P less than 0.05) between 24 and 36 h. Leukotriene B4, leukotriene C4 and histamine were present in follicular fluid at all sampling periods and did not change significantly over time. In another experiment, buffered saline or indomethacin (either 100 or 500 micrograms) was injected into preovulatory follicles on the day that they reached 35 mm in diameter to determine whether blocking intrafollicular PG synthesis would affect ovulation. The interval between intrafollicular injection and ultrasonographic detection of luteinization was significantly longer (P less than 0.05) in mares treated with 500 micrograms indomethacin. Plasma progesterone concentrations were significantly (P less than 0.05) lower in indomethacin-treated mares than in control mares on the first 5 days after injection. These results indicate that intrafollicular concentrations of PGs increase significantly before ovulation in mares and may be involved in the ovulatory process.

Use of altrenogest to prepare ovariectomized mares as embryo transfer recipients.

Altrenogest was administered to ovariectomized mares to determine if treatment would enable establishment and maintenance of pregnancy after transfer of a 7-d embryo. Three different treatment regimens were used: Group A received 22 mg altrenogest daily starting 5 d before transfer, Group B received 66 mg altrenogest daily starting 6 days before transfer, Group C received 300 mg progesterone in oil intramuscularly daily starting 5 d before transfer. Intact, ovulation-synchronized recipients were used as controls for transfer technique. Pregnancy rates were 1 6 , 2 6 , 2 5 , and 13 19 for Group A, Group B, Group C, and controls, respectively. The pregnancy rate in Group A was significantly different from controls and Group A mares had poor uterine and cervical tone. These results show that ovariectomized mares treated with altrenogest are capable of establishing pregnancy after embryo transfer. Treatment with 22 mg altrenogest appears to be insufficient for optimal pregnancy rates after transfer in ovariectomized recipients.

Use of an immediate, qualitative progesterone assay for determination of day of ovulation in an equine embryo transfer program.

An immediate, qualitative enzyme-linked immunosorbent assay (ELISA) for progesterone was evaluated for use in determining the day of ovulation in an equine embryo transfer program. Plasma samples were collected from 27 mares from the third day of estrus to the second day of diestrus for 50 cycles. Ovulation was detected by ultrasound examination per rectum. Plasma progesterone concentrations were estimated using the qualitative assay to detect the time of the rise in progesterone after ovulation. Qualitative scores were compared to progesterone concentrations for the same samples as measured by a quantitative ELISA; the correlation between the two methods, expressed as a contingency coefficient, was 0.56. The accuracy of determining day of ovulation using qualitative progesterone results was compared to that achieved using the quantitative assay or detection of the first day of diestrus by teasing. Accuracy in determining day of ovulation +/- 1 d using the three methods was qualitative, 36/50 (72%); quantitative, 44/50 (88%); and teasing, 43/50 (86%). There was a significant difference in accuracy between the qualitative and quantitative progesterone assays (P<0.05).

Periparturient events in ovariectomized embryo transfer recipient mares.

Ovariectomized mares treated with progesterone have established and maintained pregnancy after embryo transfer. This study evaluated the ability of ovariectomized embryo transfer recipients to successfully undergo parturition, raise a foal, and return to a useful reproductive status. Periparturient events in three ovariectomized embryo transfer recipient mares and three intact mares were compared. All mares foaled normally. Mammary scores were similar for both groups and all mares produced sufficient colostrum and milk to allow normal growth of healthy foals. Plasma progesterone levels decreased to < 5 ng/ml by Day 4 post partum in both groups. Progesterone concentrations continued to decrease and remained at <1 ng/ml in ovariectomized mares, but increased after the first postpartum ovulation (Day 9 to 15) in intact mares. Endometrial involution as determined by histological evaluation was complete in ovariectomized mares by Day 10 post partum and in intact mares by Day 11 post partum. As assessed by palpation per rectum and clearance of bacteria from the uterus, uterine involution was similar in all mares. The three ovariectomized mares subsequently received embryos by transcervical transfer and two of them established pregnancy. These results indicate that normal parturition, lactation, maternal behavior and uterine involution are independent of ovarian function.

Ovarian follicular response of mares to GnRH agonist (leuprolide acetate) treatment after pituitary suppression.

Follicular growth and ovulation were monitored in 18 horse mares during a control cycle and during a cycle in which the mares received a GnRH agonist, leuprolide acetate (LA; 200 or 400 mug), twice daily until ovulation. Prior to both of these cycles, follicular growth was suppressed using a 10-day estrogen-progesterone treatment regimen, with prostaglandin F-2alpha (10 mg) administered on Day 10. Four of the mares treated with LA remained anovulatory for at least 3 weeks after the end of treatment and were excluded from statistical analysis. The dosage of LA did not affect response. Treatment with LA significantly (P=0.0375) increased the percentage of large follicles per ovulation (i.e., follicles greater than 30 mm in diameter on the day on which the largest follicle reached 35 mm) and also increased (P=0.0539) the diameter of the second largest follicle. However LA did not significantly alter the number of ovulations. Mean daily concentrations of luteinizing hormone (LH) were not significantly different during treatment and control cycles. The LH in blood samples collected repeatedly on Day 19 after the start of estrogen-progesterone treatment did not show a difference in frequency or amplitude of pulses between treatment and control cycles. Mares were artificially inseminated during estrus and the embryos were recovered. Fewer embryos were recovered per ovulation from mares after treatment with LA (26%) than during the control cycle (64%). Results indicate that treatment with LA either suppressed follicular activity or induced multiple follicular growth.

24-Hour cooled storage of equine embryos.

Equine embryos were collected by transcervical uterine flush 7 d after ovulation. The flush solution was Dulbecco's phosphate buffered saline (PBS) with 1% newborn calf serum and penicillin-streptomycin. Each embryo was washed in modified Dulbecco's PBS with 1% newborn calf serum and 0.4% bovine serum albumin, and placed in 4-ml polystyrene test tube containing this same medium. Embryos were packaged in a commercial semen transport container which cooled (-0.3 degrees C/min) and maintained the embryo at 4 to 6 degrees C. After 24 h, 16 embryos were transcervically transferred into recipient mares. Of the 16 embryos, six were detected as vesicles by ultrasonography at 14 d of pregnancy, of which three were carried to term and resulted in live, normal foals. Sixteen control embryos were directly transferred without prior storage and resulted in five foals.

Caesarean section and other methods for assisted delivery: comparison of effects on mare mortality and complications.

Data from 116 mares that had caesarean section or vaginal delivery at 2 university hospitals were analysed in 5 groups, as follows: dystocia corrected by caesarean section, Group DCS (n = 48); elective caesarean section, Group ECS (n = 10); caesarean section concurrently with colic surgery, Group CCS (n = 8); assisted vaginal delivery, Group AVD (n = 22); and controlled vaginal delivery under general anaesthesia, Group CVD (n = 28). Survival rate in all mares that had caesarean section, excluding Group CCS, was 88% (51/58). All mares in Group ECS survived and Group CCS had the lowest survival rate (38%). In 98 mares with dystocia, Groups DCS (15%) and AVD (14%) had significantly lower (P<0.05) mortality rates than Group CVD (29%). There were no differences between groups for duration of dystocia. The placenta was retained in 75 (65%) of 116 mares, and for a longer period following elective caesarean section than following assisted vaginal delivery. Multiple complications (> or = 3) were recorded in 6 mares in Group CVD but not in the other groups. Of the 102 foals delivered from 98 mares with dystocia, 11 (11%) were alive at delivery and 5 (5%) survived to discharge. Survival rate for foals was 38% in Group CCS, and 90% in Group ECS. Under conditions similar to those in this study, it is calculated that caesarean section is preferable to CVD if dystocia is protracted and great difficulty and trauma is involved, even if CVD allows delivery of the foal.

Detection of chemotactic factors in preovulatory follicular fluid from mares.

Ovulation has been likened to an inflammatory process. Inflammatory cells accumulate in the ovulating follicle, presumably because of chemotactic factors. Chemotactic activity was measured in fluid aspirated from follicles of estrous mares 0, 12, 24, and 36 hours after ultrasonographic detection of a 35-mm follicle and IV treatment with 2,500 IU of human chorionic gonadotropin. Chemotaxis was assessed by measuring directional migration of equine neutrophils under agarose. Follicular fluid acted as a chemoattractant for neutrophils, but there was no significant difference in chemotactic activity among different time intervals after administration of human chorionic gonadotropin. On the basis of results of various treatments, chemotactic properties of serum and follicular fluid were similar. Chemotactic activity was significantly reduced by heating (56 C for 30 minutes) and by trypsinization and was virtually removed by charcoal treatment. Dialyzing the follicular fluid (3,500 and 8,000 molecular weight cut-off) significantly reduced the chemotactic activity of follicular fluid and serum. The importance of chemotactic factors in the process of ovulation in the mare is yet to be established.

Transcervical embryo transfer in performance mares.

Pregnancy was established by transcervical transfer of embryos from performance mares into recipient mares. Estrus was synchronized between donor (n = 17) and recipient (n = 43) mares. After a greater than or equal to 25-mm follicle was detected, donor mares were bred artificially daily until ovulation. Day of ovulation was recorded. Uterine flushes (n = 111) were performed on donor mares 7 days after ovulation, and recovered embryos were transferred transcervically to recipient mares within 2 hours. Embryos were recovered from 40.5% of uterine flushes. Of transferred single embryos, 65.7% resulted in pregnancy, detectable by ultrasonographic examination 23 days after transfer. Only 35.3% of twin embryos resulted in pregnancy. Results over a 4-year period were as follows: uteri were flushed on 14, 44, 31 and 22 occasions, and 8, 21, 15, and 11 embryos were recovered (1 embryo was not transferred), with 6, 11, 4, and 6 resulting in 30-day pregnancy in years 1 to 4, respectively.

Plasma concentrations of 13,14-dihydro-15-ketoprostaglandin F2 alpha in mares during uterine involution.

Twelve mares were allowed to foal naturally, after which they were monitored to study uterine involution. Starting on day 3 after parturition, the internal genital tract was examined per rectum manually and ultrasonographically every other day for changes in uterine characteristics and ovarian activity. By day 5, gravid and nongravid uterine horns were similar in size, and by day 7, uterine fluid was absent. On day 7 after parturition, endometrial biopsy samples were obtained for histologic evaluation, and uterine swab specimens were obtained for microbiologic culture. Uterine swab specimens from 10 of 12 mares had slight bacterial growth. The uteri of 8 of the 12 mares were histologically involuted by day 7. All mares ovulated 7 to 12 days after parturition. Concentrations of 13,14-dihydro-15-keto-PGF2 alpha (PGFM) were measured in jugular plasma samples obtained daily for 21 days after parturition. Concentrations of PGFM were low by the day after parturition, and there was no significant correlation between uterine involution and PGFM concentrations in these mares. All 12 mares were bred at the first estrus after parturition, and 9 became pregnant.

Effect of repeated collection of multiple endometrial biopsy specimens on subsequent pregnancy in mares.

Endometrial biopsy specimens (4 or 5 on each occasion) were collected from 7 mares 2, 3, or 4 times over a 50-day period prior to breeding. Four of the collection days were within 6 days of breeding. Six of the 7 mares were diagnosed as pregnant by use of ultrasonography at day 14 after ovulation. This pregnancy rate was the same as that achieved by these mares when they were bred at estrus before the start of the study. It appeared that repeated collection of multiple endometrial biopsy specimens from genitally normal mares did not adversely affect pregnancy rate.

Clinical significance of aerobic bacterial flora of the uterus, vagina, vestibule, and clitoral fossa of clinically normal mares.

Swab specimens for bacterial culture were obtained from the uterus, vagina, vestibule, and clitoral fossa of 48 mares that had normal reproductive tracts, no history of reproductive problems, and no inflammation on evaluation of endometrial biopsy. The mares were predominantly Thoroughbred and Standardbred. Swab specimens of the vagina were obtained through a sterile speculum; swab specimens of the uterus were obtained by use of a double-guarded, occluded culture instrument. Fifteen (31%) of the uterine swab specimens and 20 (42%) of the vaginal swab specimens yielded growth on aerobic culture; however, only 2 (4%) of the uterine swab specimens and 4 (8%) of the vaginal swab specimens yielded growth of more than 10 colonies. In contrast, 21 (44%) of the vestibular swab specimens and 45 (94%) of the clitoral fossa swab specimens had moderate (greater than 10 colonies in 1 quadrant) to heavy (colonies in 2 or 3 quadrants) growth of organisms on culture. Of organisms considered to be potential pathogens, Streptococcus zooepidemicus and Escherichia coli were found on bacteriologic culture of several clitoral fossa swab specimens and of some vestibular swab specimens. We did not isolate any potential pathogens from uterine or vaginal swab specimens. It appears that 1 to 10 colonies of nonpathogenic organisms could be recovered from the uterus in a substantial number of clinically normal mares even when double-guarded swabbing techniques are used, and we suggest that prebreeding culture requirements be modified to reflect this. Also, our findings indicate that the vulvovaginal fold, rather than the cervix, might be the major barrier to ascending bacterial contamination of the reproductive tract.(ABSTRACT TRUNCATED AT 250 WORDS)

Hydrops amnii in a mare.

A multiparous pregnant Welsh Pony mare was examined because of anorexia, dyspnea, and a large abdomen. Ultrasonography of the uterus revealed an excessive amount of amniotic fluid surrounding the fetus. Transabdominal ultrasonography permitted differentiation of hydrops amnii from hydrops allantois. The mare aborted a 7-month-old fetus with brachygnathia and a large, edematous umbilical cord. Hydrops amnii, an excessive accumulation of amniotic fluid in the amniotic cavity, is most commonly reported in cattle and sheep.

Medical management of urinary calculi in a stallion with breeding dysfunction.

A 9-year-old Thoroughbred stallion was examined because of breeding dysfunction and possible urethritis. The stallion had good libido and readily obtained an erection, mounted, and intromitted but did not thrust and ejaculate. After mounting the mare, the stallion would squeal and dismount. Endoscopic examination of the urethra and bladder revealed irregular, spiculate yellow crystals (< 1 cm in size) and sabulous deposits; numerous calculi were embedded in the mucosa of the bladder. Because the horse was at the start of a breeding season, the owner would not give permission for general anesthesia. Medical management was attempted, because postoperative convalescence after surgical removal of calculi might have curtailed breeding activities, and the calculi were small. Every 1 to 3 days, the bladder was lavaged with saline solution containing acetic acid, and anti-inflammatory and antimicrobial drugs were administered. The stallion was able to return to breeding mares, and sperm numbers and semen quality were good. However, urine contamination of the ejaculate was detected, suggesting that the stallion may have had a primary neurologic deficit affecting bladder control and function that was causing calculi to form secondarily because of delay in movement of urine through the urinary tract.

Mid-gestation pregnancy is not disrupted by a 5-day gastrointestinal mucosal cytoprotectant oral regimen of misoprostol.

REASONS FOR PERFORMING STUDY: To investigate effects of a 5-day oral misoprostol regimen recommended for use in horses as a gastrointestinal mucosal cytoprotectant during colic on mid-gestation pregnancies. OBJECTIVES: To monitor cervical tone, ultrasonographic characteristics of the uterus, cervix and conceptus, as well as serum progesterone and oestrone sulphate concentrations, and observations of general health, behaviour and comfort of mid-gestation mares given a 5-day course of misoprostol or control treatment. METHODS: Eleven light horse and pony mares with known breeding dates were administered 5 µg/kg bwt misoprostol orally, twice daily for 5 days. General health and pregnancy status were monitored daily during treatment via general physical examination, as well as palpation and ultrasonography per rectum of the uterus, cervix and conceptus. Jugular serum was obtained during and for 5 days following treatment for assay of progesterone and oestrone sulphate concentrations. Additionally, daily 12 h video samples of the mares were obtained to evaluate behaviour and comfort. RESULTS: All findings, including cervical tone, ultrasonographic characteristics of the uterus, cervix and conceptus, as well as progesterone and oestrone sulphate concentrations, and observations of general health, behaviour and comfort, were similar during misoprostol and control treatment. CONCLUSIONS: Treatment of pregnant mares with a gastrointestinal mucosal cytoprotectant regimen of oral misoprostol for 5 days did not disrupt pregnancy, nor adversely affect the general health and comfort of these mares. Additional investigation of treatment at earlier and later stages of gestation, for longer-term treatment, as well as evaluating neonates for developmental disturbances, would add further information on safety of misoprostol during gestation. POTENTIAL RELEVANCE: These results provide some assurance of safety of a 5-day gastrointestinal mucosal cytopretectant regimen of oral misprostol in mid-gestation pregnant mares.

Sperm ultrastructure, morphometry, and abnormal morphology in American black bears (Ursus americanus).

The objective of this study was to describe sperm ultrastructure, morphometry, and abnormal morphology in American black bears. Electroejaculation was successful in 53.8% (7/13) of the attempts, but urine contamination was common. Epididymal sperm samples were also obtained from five bears. Sperm had a paddle-like head shape and the ultrastructure was similar to that of most other mammals. The most striking particularity of black bear sperm ultrastructure was a tightening of the nucleus in the equatorial region. Although the differences were not significant in all bears, the overall decrease in sperm nucleus dimensions during transport from the caput epididymis to the cauda suggested increasing compaction of the nucleus during maturation. For ejaculated sperm, nucleus length, width, and base width were 4.9, 3.7, and 1.8 µm, respectively, whereas sperm head length, width, and base width were 6.6, 4.8, and 2.3 µm, and midpiece, tail (including midpiece), and total sperm lengths were 9.8, 68.8, and 75.3 µm. Evaluation of sperm cytoplasmic droplets in the epididymis revealed that proximal droplets start migrating toward a distal position in the caput epididymis and that the process was mostly completed by the time sperm reached the cauda epididymis. The proportion of morphologically normal sperm in the ejaculate was 35.6%; the most prevalent sperm defects were distal cytoplasmic droplets and bent/coiled tails. The morphology of abnormal sperm and the underlying ultrastructural defects were similar to that in other large domestic animals thus suggesting similar underlying pathogenesis of specific sperm defects and similar effects on fertility.