Laparoscopic Ovariectomy in Standing Mule Mares

Mules are hybrids bred from the mating of a jack donkey and a horse mare, known for their strength and resistance and still used to work in agriculture. Although they have been for long considered sterile, evidence of estrus cycle has been demonstrated together with abnormal behavior related to ovarian activity. In this study, a bilateral standing laparoscopic ovariectomy technique using the LigaSure technology was applied in 10 mare mules for treating unwanted behavioral patterns. The technique was effectively performed on these animals avoiding the risk of general anesthesia, and the use of the LigaSure technology allowed good hemostasis and reduced surgical time. Owners declared to be satisfied with the resolution of the behavior.     

Evaluation of Single-Incision Laparoscopic Ovariectomy in Standing Mares

Our objective was to compare the invasiveness of single-incision laparoscopic surgery (SILS) and multiport laparoscopic surgery (MLS) for ovariectomy in 5 standing healthy adult Thoroughbred mares. First, laparoscopic ovariectomy was performed by SILS or by MLS on the right paralumbar fossa region in a standing mare. One month after surgery, ovariectomy by the other method was performed on the left side. For surgery evaluation, the surgical time, length of incision, and amount of lidocaine used were recorded and compared between SILS and MLS. Physical examination (body temperature, heart rate, and respiration rate) and hematology (number of leukocytes and hematocrit) were performed before surgery and every day for 7 days after surgery. Similarly, the degrees of swelling, heat, pain, and incisional wound healing were evaluated (grades1-4). The length of incision and amount of local anesthetic for SILS were significantly less than those for MLS. Moreover, the scores for swelling, heat, and pain in the SILS group tended to be lower than those in the MLS group for several days after surgery. We concluded that SILS was less invasive than MLS and is therefore useful for ovariectomy in mares.     

Clients' Perspectives on the Effects of Laparoscopic Ovariectomy on Equine Behavior and Medical Problems

Because laparoscopic surgery eliminates the side effects of general anesthesia, the success and therefore the use of laparoscopic surgery continues to broaden. Laparoscopic ovariectomy, once only used to treat medical problems such as granulosa cell tumors, is now being expanded to treat behavioral problems in mares. Thirty-five mares with behavioral or medical problems were treated with ovariectomies, and their owners were later contacted and questioned concerning the effect of ovariectomy on their mares.Behavioral improvement was seen in 83% (19/23) of mares treated for behavior-related problems. Aggression problems improved in 86% (12/14) of cases, general disagreeable demeanor improved in 81% (17/21), and excitability improved in 75% (12/16) of cases in which these behaviors were previously observed. Kicking and biting improved in 73% (8/11), problems in training improved in 72% (13/18), and frequent urination and problems with other horses improved in 64% (7/11 and 9/14, respectively) of cases.Owners with nonovariectomized mares also were contacted to compare the normal progression of mare behavior over time with the behavioral change in ovariectomized mares. A statistically significant change in behavior of ovariectomized mares over nonovariectomized mares was seen in the categories of decreased aggression (P < .01), decreased training problems (P < .025), decreased frequency of problem behaviors (P < .001), and improved overall behavior (P < .01).In cases in which medical problems such as granulosa cell tumors, ovarian cysts, and cycle-related colic were treated with ovariectomy, all of the clients were very satisfied with the treatment, whereas clients attempting to treat cycle-related laminitis were dissatisfied.     

Surgical Management of Enterocutaneous Fistula in a Mare

Enterocutaneous fistulas are reported to be sequelae of congenital umbilical hernia or penetrating trauma to the equine patient's abdomen. An enterocutaneous fistula is considered to be the least common clinical presentation in a horse with incarcinated umbilical hernia, and may be life-threatening if not managed timely. This case report describes an enterocutaneous fistula in a mare as a sequela to congenital umblical hernia. The mare had an uneventful recovery after surgical repair and delivered a healthy foal on subsequent follow-up. The report highlights the need to repair congenital umbilical hernias (regardless of the size), if they do not resolve by the age of 6 to 12 months.     

Absence of Any Specific Diurnal Pattern in the Time of Ovulation in the Mare

This study investigates a long-held belief that mares tend to ovulate during the night. If this were so, a strategic examination regimen might replace multiple daily examinations when the time of ovulation needs to be known to within a few hours. Over 500 mares were examined at least three times daily to determine the time, to within ±4.25 hours, of 896 ovulations. The time of ovulation was determined as midway between the pre-ovulatory and post-ovulatory examinations. Three broad peaks of incidence of ovulation occurred at 5:00 am, 2:00 pm, and 10:00 pm. The interval between peaks was 9, 8, and 7 hours. during which 34.2% (5:00 am to 2:00 pm), 44.3% (2:00 pm to 10:00 pm), and 21.3% (10:00 pm to 5:00 am) of ovulations occurred. The percentage of ovulations occurring in the period 2:00 pm to 10:00 pm was significantly higher (P < .001) than in the period 10:00 pm to 5:00 am and significantly higher (P < .01) than in the period 5:00 am to 2:00 pm. The data showed that mares ovulated at all times of the day and night, with some increased incidence between 2:00 pm and 10:00 pm. Therefore, no strategic examination regimen was possible.     

A Modified Viborg's Triangle Approach for Surgical Drainage of Guttural Pouches Empyema Through Placement of a Fenestrated Tube in a Mare

A 7-year-old mare was brought to the clinic with a history of falling 1 month earlier and bilateral mucosanguinous nasal discharge, respiratory distress, and bilateral swelling caudal to the posterior margin of vertical rami of mandibles for 3 weeks. Lateral radiography of the neck region revealed gas-filled soft tissue density caudal to the mandibles. Empyema of the guttural pouches was diagnosed and surgical drainage was planned by placement of a fenestrated tube. A skin incision was made at the dependent part of the swelling in Viborg's triangle on both sides; guttural pouches were exposed and mucosanguinous contents drained by lancing the pouches. Fenestrated tubes, prepared from the tubing of a urine collection bag, were fixed into the guttural pouches by anchoring to the wall of the pouches and skin. Postoperatively, 5 g of streptomycin plus 4 million IU of penicillin and 75 mg of meloxicam were administered intramuscularly for 7 days and 5 days, respectively. Guttural pouches were lavaged daily with 0.1% potassium permanganate solution (KMnO₄) and 5% topical povidone iodine diluted with normal saline solution to 1%. Tubes from both sides were removed on the 14th postoperative day, and wounds healed by second intention. The animal recovered uneventfully.     

Follicular Fluid Prolactin and the Periovulatory Prolactin Surge in the Mare

Prolactin may play multiple roles in equine reproduction. Prolactin appears to be associated with seasonal reproduction, and fluctuating prolactin levels during the estrous cycle suggest that it may play a role in estrous cyclicity as well. The purpose of this research was to investigate the activity of prolactin during the follicular phase of the estrous cycle. In experiment 1, prolactin concentrations were determined from plasma samples collected at least every other day throughout the estrous cycle. Periovulatory (ovulation ± 1 day) prolactin concentrations were compared with concentrations during early diestrus (days 2−10 postovulation). In experiment 2, prolactin concentrations were measured in follicular fluid collected from 74 follicles of various sizes. Follicles were grouped into small (≤20 mm), medium (21−35 mm), and large (>35 mm) size categories. Prolactin concentrations increased during the periovulatory period in cycling mares. This periovulatory surge was superimposed on baseline prolactin concentrations that varied with season. Prolactin was present in significant quantities in the follicular fluid. Follicular fluid prolactin concentrations were lowest in small follicles and increased in medium and large follicles. Concentrations did not differ between medium and large follicles. Follicular fluid prolactin concentrations were lower in autumnal follicles compared with summer follicles of comparable size. It is possible that the short-term surge in circulating prolactin around ovulation could be linked to the significant levels of prolactin in follicular fluid. Ovulation releases a relatively large volume of fluid into the peritoneum. The prolactin in this fluid could be a contributor to the periovulatory prolactin surge.     

Effect of Follicle Size and Follicle-Stimulating Hormone on Ovulation Induction and Embryo Recovery in the Mare

The timing of ovulation is an important component to many equine breeding strategies. The action of luteinizing hormone on ovulation induction has been recognized; however, potential effects of follicle-stimulating hormone (FSH) have been less defined. Objectives of this study were to determine whether (1) mares could be induced to ovulate follicles ≤30 mm; (2) equine FSH (eFSH) has a positive effect on ovulation induction, and (3) ovulation of small follicles would affect embryo recovery. Light-horse mares (n = 12) between 4 and 10 years of age were assigned to treatments when they had a dominant growing follicle with a mean diameter of 24, 28, or 35 ± 2 mm and endometrial edema. Treatments were (1) H35, human chorionic gonadotropin (hCG) at 35 ± 2 mm; (2) F35, eFSH at 35 ± 2 mm; (3) H28, hCG at 28 ± 2 mm; (4) FH28, eFSH and hCG at 28 ± 2 mm; (5) D28, deslorelin (gonadotropin-releasing hormone [GnRH] analog) at 28 ± 2 mm; (6) FH24/H24, hCG or eFSH and hCG at 24 ± 2 mm. Mares’ reproductive tracts were scanned at 24 ± 2-hour intervals after treatment to detect ovulation. Mares were inseminated, and embryos were collected. Numbers of mares that ovulated within 48 ± 2 hours after treatment were: H35, 8/8 (100%); F35, 8/14 (57%); H28, 7/12 (58%); FH28, 9/12 (75%); D28, 3/7 (43%) and FH/H24, 4/14 (29%). The number of mares that ovulated in 48 ± 2 hours for H35 was not different from that for FH28 but was higher (P < .05) than all other groups. Embryo recovery rates, diameters, developmental stages, and morphology scores were not different for mares ovulating 48 hours or less versus more than 48 hours after treatment or among treatment groups. Results of this study demonstrate that follicles ≤30 mm can be induced to ovulate with no effect on embryo recovery or quality, as assessed by stereomicroscopy.     

The Effect of Sulpiride Treatment During the Periovulatory Period on Prolactin Concentration and Ovulation in the Mare

Sixteen estrous cycles from 10 cyclic mares were randomly assigned to a control or sulpiride group (n = 8 each). All mares received 1,500 IU of human chorionic gonadotropin (hCG) (hour 0) during estrus with a follicular diameter ≥32 mm. Mares were scanned every 12 hours until ovulation. In the treatment group, beginning at hour 0, each mare received 1.5 mg/kg of sulpiride every 12 hours intra-muscularly until ovulation or formation of a luteinized unruptured follicle (LUF). Concentrations of luteinizing hormone (LH) and prolactin (PRL) were measured by radioimmunoassay. In each group, there were 10 preovulatory follicles for the eight cycles. The ovulation rate (9/10, 90%) was similar in the control and sulpiride groups. Two mares formed an LUF, which was first detected at hours 48 and 72 for the sulpiride and control mares, respectively. The interval from hCG to ovulation was 49.5 ± 11.1 and 43.5 ± 5.8 hours, for the control and sulpiride groups, respectively (P > .5). LH followed the typical preovulatory surge pattern, with no difference between groups (P > .5). Sulpiride administration increased PRL concentration in treated mares at 24 (P < .1), 36, and 48 hours (P < .05) after treatment. In conclusion, sulpiride administration every 12 hours increased PRL concentration in treated mares after 24 hours of the beginning of treatment. However, at this time window and concentration, PRL did not have any effect on ovulation. The control mare that developed an LUF had a PRL concentration similar to other ovulatory control mares (always ≤10 ng/mL).     

The Effect of Manual Removal of Placenta Immediately after Foaling on Subsequent Fertility Parameters in the Mare

Retained placenta is considered to be a common problem in postpartum mares. The incidence varies from 6% to 54% depending on the breed, with higher incidence in heavy draught mares than in light-weight mares. Retained placenta has been linked to lower postpartum oxytocin concentration, impaired uterine involution, and dystocia. The objective of this study was to assess the effect of early manual removal of placenta immediately postpartum on subsequent fertility parameters (development of free intrauterine fluid, inflammatory status of endometrium, and on pregnancy rates) and to compare them with mares with spontaneous expulsion of placenta. A total of 29 mares, mainly Irish draught, were closely monitored during foaling by closed circuit television and allocated to two groups: (1) mares that expelled the placenta spontaneously within 3 hours of foaling; and (2) mares that were cleansed manually immediately after foal delivery. All mares were examined and scanned 5 and 9 days postpartum, and free intrauterine fluid was recorded; endometrial swabs were taken 9 days postpartum for endometrial cytology and culture. None of the fertility parameters analyzed showed statistical difference between groups 1 and 2. Therefore, it can be concluded that early manual removal of placenta has no detrimental effects on subsequent fertility of mares and, therefore, can be recommended when a veterinarian attends a foaling.     

虎斑颈槽蛇消化、呼吸和生殖系统的解剖

虎斑颈槽蛇（Ｒｈａｂｄｏｐｈｉｓｔｉｇｒｉｎａ）是分布比较广泛的爬行动物。本文主要对其消化、呼吸、生殖系统的形态结构特征进行了较详细报道。     

去势对白来航母鸡垂体和肾上腺的影响

垂体和肾上腺在摘除卵巢的雌性动物性激素合成过程中起到重要作用。为研究去势对白来航母鸡垂体和肾上腺的影响,实验对6只9周龄白来航母鸡进行卵巢摘除手术,饲养至97周龄时,检测去势白来航母鸡与同周龄未去势母鸡的血清性激素水平、冠高和距长,比较分析垂体重、肾上腺重差异,并检测垂体发育相关基因GREB1的表达量。结果显示:去势母鸡雌二醇浓度(P<0.05)、肾上腺重量(P<0.01)以及GREB1相对表达量(P<0.05)低于未去势母鸡;冠高、距长和垂体重量高于未去势母鸡(P<0.05)。可见,摘除母鸡卵巢可抑制肾上腺发育,促进垂体发育。     

Effect of Dose of Cloprostenol on the Interval to Ovulation in the Diestrous Mare: A Retrospective Study

Although the ovulatory effects of prostaglandins are well documented in several domestic species including horses, there has been little attention paid to the use of this ovulatory effect for clinical purposes. Mares often grow large follicles during the luteal phase that may or may not ovulate before progesterone levels decline. Clinical observations of administering prostaglandins in diestrous mares with large follicles suggest that there may be a negative correlation between follicular diameter and interval from treatment to ovulation. The objectives of this study were twofold: to investigate the cloprostenol dose rate effect on interval to ovulation and to confirm the negative correlation between follicular diameter and interval to ovulation. The hypothesis tested was that high doses of cloprostenol given in diestrus to mares with larger follicles would induce ovulation more rapidly than in mares given lower doses or with smaller follicles. To test the hypothesis, a total of 1,234 estrous cycles were induced with different doses of cloprostenol (ranging from 8.75 to 625 μg). All mares had at least one follicle of 28 mm or larger. Dominant follicles were followed by transrectal ultrasound examinations every other day until ovulation was detected. There was a significant effect of dose (P < .000) and follicular diameter (P < .000) on the interval from treatment to ovulation. The shortest mean interval (2.4 days) was observed after administration of 625 μg in mares with follicles 36 mm or larger, whereas the longest (4.9 days) occurred after 8.75 μg in follicles of 28 to 31 mm.     

Corpus Luteum Vascularization and Progesterone Production in Autumn and Winter Cycles of the Mare: Relationship Between Ultrasonographic Characteristics of Corpora Lutea and Plasma Progesterone Concentration in the Last Cycles Before Anestrus

In 20 estrus cycles of 15 mares, Color Doppler ultrasound of corpora lutea and plasma progesterone concentration (P4) was analyzed on days 6, 10, 14, 16, and 18 after ovulation. Progesterone concentration was positively correlated with corpora lutea cross-sectional area (CSA), vascularized area (VA), and index of vascularization (IV = VA/CSA) (P < .0001). Cross-sectional area, VA, and IV in corpora lutea of mares with P4 < 1 ng/mL were significantly lower than in corpora lutea of mares with P4 > 1 ng/mL. Mares with CSA < 3,473 pixels, VA < 25.5 pixels, and IV < 7.6% were prone to express P4 < 1 ng/mL 25.4, 7.9, and 7.6 times more than mares with higher values, respectively. Corpus luteums analyzed parameters differed significantly between last cycles (LCs) of the breeding season and previous cycles until day 14 after ovulation (P < .05). No significant differences were found in P4 between LCs and previous ones.     

《动物病理解剖学》课程多媒体教学的优势与不足

《动物病理解剖学》是动物医学专业必修的一门基础课程,同时也是基础动物医学向临床动物医学过渡的桥梁课程．其主要内容是通过组织形态结构的变化来阐述疾病的发生机理。因此,图文并茂的多媒体教学方式在该课程教学中被广泛应用。针对多媒体教学在《动物病理解剖学》课程中的优势与不足进行剖析,并提出改善方案,从而进一步提高《动物病理解剖学》课程的教学效果。