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in Journal of the American Veterinary Medical Association

SUMMARY

Three ejaculates from each of 3 stallions were used to evaluate a computerized system (Hamilton-Thorn motility analyzer; htma) for measuring equine spermatozoal motility. Variance components (ejaculate-within-stallion, chamber-within-ejaculate, and microscopic field-within-chamber) were determined for each stallion after diluting ejaculates to 25 × 106 spermatozoa/ml with a skim milk-glucose seminal extender. The htma was compared with frame-by-frame playback videomicrography (video) for determining: percentage of spermatozoal motility and spermatozoal number in microscopic fields; curvilinear velocity and straight-line velocity of individual spermatozoa for 5 track types; and repeatability of those velocity measurements. The effect of spermatozoal number per microscopic field on incidence of intersecting spermatozoa and the outcome of intersecting spermatozoa also were evaluated. Greatest variability in motility measures was generally attributed to the microscopic field-within-chamber component. The htma was highly correlated with video for estimation of spermatozoal numbers per microscopic field (r = 0.99; P < 0.001) and motility (r = 0.97; P < 0.001); however over the entire range of spermatozoal numbers, the htma yielded higher spermatozoal numbers per microscopic field (P < 0.05) and higher motility (P < 0.05) than did video. The htma- and video-derived measurements of curvilinear and straight-line velocities were highly correlated for all spermatozoal track types, but both measures were higher (P < 0.05) by use of the htma than by use of video for most track types. For 3 of 5 track types, measurements of curvilinear and straight-line velocities were less variable (P < 0.05), using the htma, rather than video. Using the htma, the number of intersecting spermatozoa was highly correlated with spermatozoal numbers per microscopic field (r = 0.97; P < 0.001). The percentage of erroneous track interpretations involving intersecting spermatozoa was high (85.3 ± 2.7%). The htma was a reliable system for determining percentage of spermatozoal motility and velocity measures in video recordings of equine semen diluted to spermatozoal concentration of 25 × 106/ml prior to evaluation.

Free access
in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association

Summary

From 1980 to 1989, 8 cesarean sections were performed on an elective basis in 5 mares. Four mares had partially obstructed pelvic canals; 2 of these mares had previously lost foals because of dystocia. Cervical adhesions that might obstruct passage of the fetus through the pelvic canal was suspected in the fifth mare. Cesarean section was performed prior to mares entering the first stage of labor. Readiness for birth was estimated by development of the mare's mammary gland and the presence of colostrum in the udder. A ventral midline celiotomy provided excellent exposure and healed without complications in all instances. Eight viable foals were produced. One foal developed bacterial pneumonia and septicemia after surgery and died. Follow-up evaluation of the 7 foals discharged from the hospital failed to reveal complications associated with elective cesarean section.

All mares survived the procedure. Fetal membranes were retained for up to 72 hours following surgery; however, systemic complications secondary to retained placenta did not develop. Three mares were bred subsequent to elective cesarean sections, with each mare conceiving the year following surgery. Three foals were produced by 1 mare and 2 foals have been produced by another mare by elective cesarean sections.

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in Journal of the American Veterinary Medical Association

Summary

Plasma luteinizing hormone and progesterone concentrations, time to onset of estrus, and pregnancy rates were determined in nonlactating anestrous does given 1 of 4 treatments: subcutaneous ear implants containing 3 mg of norgestomet for 9 days (nor; n = 6); subcutaneous administration, using osmotic minipumps, of 250 ng of gonadotropin-releasing hormone (GnRH)/h for 48 hours (GnRH; n = 6); 3 mg of nor for 9 days, followed immediately by 250 ng of GnRH/h for 48 hours (nor + GnRH; n = 6); or no treatment (control; n = 6). During the 72-hour period after removal of nor or insertion of GnRH pumps, 6 of 6, 0 of 6, 6 of 6, and 3 of 6 does were observed in estrus at a mean (± se) of 49 (± 3.0), 0(± 0), 32 (± 2.0), and 35 (± 13.8) hours in groups nor, GnRH, nor + GnRH, and control, respectively. Time from end of treatment to peak concentrations of luteinizing hormone were 56 ± 4.0, 28 ± 4.7, 34 ± 4.3, and 41 ± 9.7 hours (mean ± se) for nor, GnRH, nor ± GnRH, and control, respectively. Peak concentrations of luteinizing hormone were significantly greater and occurred significantly later in does given nor. Progesterone concentrations in does that became pregnant increased to concentrations ≥ 1.0 ng/ml 3 to 5 days after breeding and remained high.

Functional corpora lutea (cl) was found in 6 does that did not become pregnant, 1 cl was associated with pseudopregnancy and 1 cl was associated with ovulation prior to placement of the GnRH pumps. Functional cl failed to form in 10 of the 12 does in groups GnRH and control. Does had either continual low concentrations of progesterone (3 does) or short-term increases in concentrations of progesterone (7 does). Conception rates for does in groups nor, GnRH, nor + GnRH, and control were 83%, 0%, 50% and 0%, respectively. Four does given GnRH and 3 control does were observed in estrus and were bred during the subsequent 2-week period. All of these does, except 1 control became pregnant subsequent to these breedings.

The treatments nor and nor + GnRH were effective in inducing a synchronized estrus in dairy goats. However, the use of bucks to detect estrus may have introduced the buck effect and enhanced the performance of nor alone, which has not been this effective in other studies with small ruminants.

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in American Journal of Veterinary Research

Abstract

Case Description—6 mares with pyometra secondary to transluminal cervical adhesions were examined.

Clinical Findings—Reasons for hospital admission included infertility (5 mares) and acute colic (1 mare). In the 6 mares, palpation per rectum of the reproductive tract revealed uterine distention, and transrectal ultrasonography confirmed the presence of echogenic fluid accumulation within the uterus. Cervical palpation during vaginal speculum examination indicated transluminal cervical adhesions. Three mares had severe distortion of the cervix as a result of diverticula and fibrosis. All 6 mares had a diagnosis of pyometra secondary to transluminal cervical adhesions.

Treatment and Outcome—Initially, the cervical adhesions were manually broken down to establish a patent cervical lumen to accommodate a uterine lavage catheter. A sample of the uterine content was obtained for bacteriologic culture and antimicrobial susceptibility testing, and the uterus was lavaged with 0.05% povidone-iodine solution to remove the mucopurulent exudate. Once the uterus was evacuated, cervical surgery was performed in standing mares following sedation and caudal epidural anesthesia. A full-thickness wedge-shaped defect was made in the dorsolateral aspect of the cervix that created a permanent opening to the uterus. Postoperative care included applying topical medication to the cervix to reduce the recurrence of adhesion formation. All 6 mares had patent cervices and resolution of pyometra following surgery.

Conclusions and Clinical Relevance—Cervical wedge resection enabled treatment of pyometra in mares with transluminal cervical adhesions, without the need for ovariohysterectomy. (J Am Vet Med Assoc 2015;246:1354–1357)

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in Journal of the American Veterinary Medical Association

Summary

Postoperative performance and behavioral patterns were investigated retrospectively in 23 client-owned mares after bilateral ovariectomy via colpotomy. The interval from surgery to postoperative inquiries ranged from 9 to 67 months. Information obtained from review of the medical record and client interviews included the reason for ovariectomy, postoperative complications, problems identified by owners after discharge of the mare from the hospital, postoperative level of athletic performance, postoperative signs of estrus, and overall owner satisfaction. Reasons given by owners for having mares ovariectomized were behavioral modification (16 mares), use as embryo-transfer recipients (3 mares), use as mount mares for collecting semen (2 mares), elimination of chronic colic during estrus (1 mare), and sterilization for registration (1 mare). Postoperative complications developed in 4% (1/23) of the mares; however, problems were noticed by the owners of 4 other mares after discharge from the hospital. Continuing signs of behavioral estrus were detected in 35% (8/23) of the mares, but in only in 9% (2/23) was the behavior judged to be objectionable by the owner. Of 12 mares used in performance events prior to bilateral ovariectomy, 10 were judged to be competing at greater than preoperative levels, 1 was judged to be competing at the same level, and 1 was judged to be competing at less than preoperative level of performance. Of 18 owners, 14 were satisfied, 2 were undecided, and 2 were dissatisfied with their mare after it had had bilateral ovariectomy.

Free access
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To describe the signalment, clinical features, and outcome for male horses with urethral rents following perineal urethrotomy (PU) or corpus spongiotomy (CS).

DESIGN Retrospective case series.

ANIMALS 33 horses.

PROCEDURES Medical records of male horses examined because of hematuria or hemospermia caused by urethral rents that underwent PU or CS at a referral hospital between 1989 and 2013 were reviewed. Data regarding signalment, clinical features, urethroscopic findings, surgical treatment, and outcome were recorded. Long-term follow-up information was obtained by telephone interviews.

RESULTS Age of the study population ranged from 3 to 18 years. Nineteen geldings and 1 stallion were examined because of hematuria, of which 13 and 7 underwent PU and CS, respectively, at a mean of 56 days after onset of clinical signs. Thirteen stallions were examined because of hemospermia, of which 7 and 6 underwent PU and CS, respectively, at a mean of 193 days after onset of clinical signs. Hematuria resolved following 1 surgical procedure in all 17 horses for which long-term information was available. Of the 12 stallions for which long-term information was available, 7 had resolution of hemospermia after 1 PU or CS and 5 developed recurrent hemospermia that required additional PUs or CSs (n = 3) or primary closure of the urethral rent (2).

CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that PU and CS were reliable treatments for resolution of hematuria in male horses with urethral rents; stallions with urethral rents may require multiple PUs or CSs or primary closure of the rent for resolution of hemospermia.

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in Journal of the American Veterinary Medical Association