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BACKGROUND: Goats are increasingly popular as both production animals and pets. The frequency of and factors associated with periparturient reproductive complications in goats are largely unreported. OBJECTIVES: (1) To report the frequency of periparturient reproductive complications in does presented to university veterinary hospitals and (2) to identify factors associated with uterine tears in the study population. ANIMALS: A total of 198 periparturient does presented to 9 university veterinary hospitals from October 2021 to June 2022. METHODS: Multicenter, cross-sectional study, with data collected from questionnaires completed by attending veterinarians. Logistic regression was used to identify factors associated with diagnosis of uterine tears. RESULTS: Ninety-three (47%) does had at least 1 periparturient reproductive complication. Periparturient complications included retained fetal membranes (n = 38, 26%), vaginal or perineal trauma (n = 33, 19%), uterine tears (n = 32, 18%), metritis (n = 22, 13%), uterine or vaginal hemorrhage (n = 8, 5%), Cesarean section complications (n = 8, 8%), and uterine prolapse (n = 1, 0.5%). A positive interaction effect was found between small breeds (Nigerian Dwarf and Pygmy) and manipulation on the farm by a layperson upon diagnosis of uterine tears (odd ratios [OR], 5.48; 95% confidence interval [CI], 1.41, 21.25; P = .01). CONCLUSIONS AND CLINICAL IMPORTANCE: Periparturient reproductive complications were common. Small breed combined with manipulation on the farm by layperson was associated with diagnosis of uterine tears. Clients should be educated that in the event of dystocia, small breed does are at greater risk of uterine tears and prompt veterinary intervention is critical.

Abstract Background Goats are increasingly popular as both production animals and pets. The frequency of and factors associated with periparturient reproductive complications in goats are largely unreported. Objectives (1) To report the frequency of periparturient reproductive complications in does presented to university veterinary hospitals and (2) to identify factors associated with uterine tears in the study population. Animals A total of 198 periparturient does presented to 9 university veterinary hospitals from October 2021 to June 2022. Methods Multicenter, cross‐sectional study, with data collected from questionnaires completed by attending veterinarians. Logistic regression was used to identify factors associated with diagnosis of uterine tears. Results Ninety‐three (47%) does had at least 1 periparturient reproductive complication. Periparturient complications included retained fetal membranes (n = 38, 26%), vaginal or perineal trauma (n = 33, 19%), uterine tears (n = 32, 18%), metritis (n = 22, 13%), uterine or vaginal hemorrhage (n = 8, 5%), Cesarean section complications (n = 8, 8%), and uterine prolapse (n = 1, 0.5%). A positive interaction effect was found between small breeds (Nigerian Dwarf and Pygmy) and manipulation on the farm by a layperson upon diagnosis of uterine tears (odd ratios [OR], 5.48; 95% confidence interval [CI], 1.41, 21.25; P = .01). Conclusions and Clinical Importance Periparturient reproductive complications were common. Small breed combined with manipulation on the farm by layperson was associated with diagnosis of uterine tears. Clients should be educated that in the event of dystocia, small breed does are at greater risk of uterine tears and prompt veterinary intervention is critical.

OBJECTIVE The objectives of this study were to evaluate the prevalence of chronic Anaplasma marginale infection in beef bulls from eastern Kansas and compare breeding soundness parameters between A marginale-infected and uninfected bulls. We hypothesized that bulls with chronic anaplasmosis would have inferior breeding soundness exam (BSE) outcomes as a result of persistent A margina/e infection or the consequence of initial clinical disease compared to uninfected bulls. ANIMALS 535 client-owned beef bulls from eastern Kansas undergoing routine BSE. METHODS Complete BSEs were conducted by participating veterinarians according to the second edition of the Society for Theriogenology Manual for Breeding Soundness Examination of Bulls . Blood samples were collected for PCV determination and analysis of A marginale infection status via quantitative PCR and cELISA. Logistic and linear regression methods were used to evaluate factors associated with A marginaje infection status and BSE parameters. RESULTS Prevalence of chronic A marginale infection was 46 % (245 / 535) among bulls. Unsatisfactory BSE outcome was not statistically associated with chronic anaplasmosis in this study population, although more bulls with chronic anaplasmosis had unsatisfactory BSE outcomes (15.0 ± 2.4% vs 12.0 ± 2.2%) CLINICAL RELEVANCE Chronic anaplasmosis is prevalent among eastern Kansas breeding bulls; however, no negative association between chronic anaplasmosis and breeding soundness at time of BSE was observed. [ABSTRACT FROM AUTHOR]

The protozoan Tritrichomonas foetus causes early embryonic death in cattle, there are no legal options for treating this parasite in the United States, and there are few developed protocols for cleaning veterinary and obstetrical equipment that may have been contaminated with trophozoites. In this study, we evaluated bleach, ethanol, acetic acid, chlorhexidine gluconate, and hydrogen peroxide solutions for the ability to kill trophozoites in vitro. Our findings suggested that ethanol and bleach could adequately disinfect tools and equipment. Acetic acid, chlorhexidine, and hydrogen peroxide had applications as surface disinfectants in addition to potential as local topical treatments due to their past uses in veterinary theriogenology. Chlorhexidine gluconate demonstrated trophocidal effects by damaging parasite cell membranes and had the lowest effective concentration 50 (EC50) of any compound tested and was in the micromolar range. These findings, in conjunction with accepted clinical uses of chlorhexidine gluconate suggest that this is a convenient agent for disinfecting equipment. In addition, topical use of chlorhexidine is relatively common, setting the stage for further investigation of this compound as a topical therapeutic option for bovine trichomonosis.

The size of an animal's pelvis can have a substantial impact on the ease or difficulty of giving birth, which can vary depending on the breed. Radiography is a medical imaging technique that is commonly utilized in clinical cases to assess pelvic dimensions. The present retrospective, observational study was designed to evaluate pelvimetric differences in radiographic images of British Shorthair (BS) cats with dystocia and eutocia. Pelvimetric values (linear distance, angle, area, height/width) for ventrodorsal and laterolateral radiographic images were recorded in 15 BS cats with dystocia and 15 BS cats with eutocia. Statistical analysis of the obtained measurement values was performed. When the pelvimetric data were examined overall, it was seen that mean values, except the PL (pelvis length) measurement, were higher in cats with eutocia than in cats with dystocia. Vertical diameter, conjugate vera, coxal tuberosities, transversal diameter, acetabula, pelvic inclination, ischiatic arch, pelvis inlet area (PIA), and pelvic outlet area (POA) values were significantly higher in cats with eutocia than in cats with dystocia (P < 0.05). Mean PIA and POA measurement values in cats with dystocia were 22.89 ± 2.38 cm2 and 19.59 ± 1.90 cm2, respectively; in cats with eutocia, the mean was calculated as 27.16 ± 2.76 cm2 and 23.18 ± 1.88 cm2, respectively. In conclusion, the present study revealed that pelvimetric values, except the PL measurement, were higher in cats with eutocia than in cats with dystocia. Findings can be used to assist veterinarians in future clinical decision‐making for pregnant BS cats. [ABSTRACT FROM AUTHOR]

A 10-year-old female spayed mixed breed dog was evaluated for diarrhea and vomiting. Diagnostic imaging demonstrated the presence of an intracardiac mass. A modified Seldinger technique was used to access the right jugular vein, and an endomyocardial biopsy forceps was introduced through a sheath to obtain several biopsies. Histopathology and immunohistochemistry demonstrated a paraganglioma. The dog underwent 1 fraction of radiotherapy and l-asparaginase chemotherapy and was discharged. The dog developed a pulmonary thromboembolism 2 days after radiotherapy and chemotherapy, and the owner elected humane euthanasia. Although long-term assessment of treatment response was unable to be performed, this novel diagnostic option could be considered for similar cases due to success in obtaining a histopathologic diagnosis, which is essential in developing a disease-specific treatment plan. This report also describes the use of radiotherapy for primary treatment of an intracardiac neoplasm, which can be a consideration in the future.

In this study, it was aimed to detect the effects of conventional semen, sexed-semen and embryo transfer on pregnancy rates in Holstein dairy cows. In the study, a total of 139 healthy cows with the serum progesterone > 8 ng/ml were used as animal material. Estrus synchronization protocol was applied and cows were divided into three different groups as conventional semen group (G1, n=46), sexed semen group (G2, n=47), and embryo transfer group (G3, n=46) considering age, body condition score, lactation number, and body weight. Cows in G1 and G2 were inseminated with conventional semen and sexed-semen, respectively. Embryo transfer was performed to cows in Group 3 (n=46) 7th day after estrus. The embryos were transferred to recipients as freshly. Pregnancy examinations for the cows were conducted on the 30th and 60th days of gestation. The statistical analysis of the obtained results was performed. Pregnancy rates were detected as %50, %46,8 and %69,56 in G1, G2, and G3 respectively on 30th day. On 60th day, however, pregnancy rates were %45.60, %42.55 and %67.39 in G1, G2, and G3 respectively due to embryonic losses. The pregnancy rate was significantly higher in the embryo transfer group (G3) compared to the conventional semen (G1) and sexed-semen (G2) group (p<0.05) on both 30th and 60th days. There was no significant difference between G1 and G2 (p>0.05). Findings led to the conclusion that higher serum progesterone level may increase pregnancy rate in cattle. In addition, it is evident that embryo transfer has the potential for widespread use in the field of veterinary medicine in terms of genetic progress. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 07-year-old Thoroughbred mare with estrus behavior. Topics include ovulation fossa being perceptible on both ovaries where the left ovary being approximately half the size of the right ovary; and speculum examination revealing minimal bruising of the vagina and vestibule, and a contracted cervix.

The article presents a case of a 3-year-old Holstein Friesian cow which delivered a healthy heifer calf followed by the expulsion of an abnormal mass and fetal membranes to discuss the possible diagnosis or description for the abnormal mass and heifer calf. Based on histologic examination, there is a testicular tissue in the abnormal mass and a diagnosis of amorphus globosus and a freemartin heifer calf was made.

The article presents a case study of a three year-old Aberdeen-Angus bull for failure to have a straight penis during erection. It mentions that bull had a clinically normal gait with no signs of lameness, no abnormalities of the eyes or adnexal structures, and vital signs within reference limits. It discusses that apical ligament of the penis as an ex-tension of the outer longitudinal layer of the tunica albuginea.

abstract: The jaguar (Panthera onca), the largest felid in the Americas, has been classified by IUCN as ‘near-threatened’. The purpose of this review was to gather the current knowledge on jaguar reproduction. Information from over forty-five sources has been selected. Jaguars have been classified as polyestrous with generally an induced ovulation, with a moderate incidence of spontaneity. Estrus, estrous cycle and pseudopregnancy lengths varied from 4 to 17, and 22–63, and 14–67 days, respectively. Ejaculate volume is around 3.9 ml and the spermatogenic cycle takes 57.7 ± 0.07 days. In spite of its low gonadosomatic index, the whole spermatogenic process in jaguars is more efficient than that of the domestic cat. Although minor seasonal variation in most reproductive traits has been found at the studied latitudes, local rains seemed to have an effect. Gestation takes from 91 to 111 days. Females queen one to four immature cubs. As evidenced by the wide range reported for most reproductive parameters further work is still necessary to achieve fundamental knowledge that could facilitate breeding, management and conservation activities.

A case study of 3-week-old sexually intact male Brahman twin calf is presented for evaluation of an enlarged scrotum to the Food Animal Reproduction and Medicine Service, College of Veterinary Medicine, University of Florida. Topics include examines the farm reported that at birth, assistance was required as the twins were delivered vaginally and the calves were tubed with colostrum replacer initially and remained in a pasture with the dam.

A case study of a 1-year-old primiparous female Boer cross goat was presented to the J. T. Vaughn Large Animal Teaching Hospital at Auburn University College of Veterinary Medicine with a history of prolonged first-stage labor following his pregnancy. Topics include dog owner observed visceral organs protruding the emergency service for assistance; and Maternal abdominal organs can potentially exit the abdomen following a vaginal tear, with thoracic organs will be retained by the diaphragm.

The article presents a case study of a 17-year-old 506-kg multiparous American Quarter Horse mare was referred to the Louisiana State University Veterinary Teaching Hospital Theriogenology Service because of a 1-year history of infertility characterized by nymphomania, anovulatory cycles, and an enlarged right ovary. The article discusses that the mare had reportedly produced 5 or 6 foals throughout her life, with the last foal born approximately 2 years before the present examination.

The article presents a case study of a 2-year-old 54.5-kg female alpaca was evaluated at the Oregon State University Veterinary Teaching Hospital (OSU-VTH) because of a 5-day history of progressive stranguria, tenesmus, and signs of abdominal pain. The article discusses that the Transrectal ultrasonographic examination of the alpaca's reproductive tract revealed an enlarged uterus that was distended with hypoechoic fluid.

The article present case study of a 2-year-old 14.7-kg (32.3-lb) sexually intact female Australian Shepherd was referred to the Louisiana State University Veterinary Teaching Hospital (LSU VTH) Theriogenology Service for evaluation because of a 1-week history of anorexia and vomiting and a 7-week history of serosanguineous discharge from the vulva since preterm labor and delivery (50 days after mating) of 9 stillborn pups.

The article presents a case study related to 8-year-old 47-kg nulliparous sexually intact female Vietnamese potbellied pig has presented to the Michigan State University Large Animal Surgery Service for evaluation because of a 30-hour history of tissue protruding from the vulva. Topics include the small amount of tissue had protruded from the pig's vulva after estrus but had resolved uneventfully, and the pig had been vaccinated with tetanus toxoid a month before the present examination.

Historical evidence of acupuncture predates written history. It has been a component of Traditional Chinese veterinary medicine for many generations and is officially recognized in recorded history for treating equine disease in the Zhou Dynasty, circa 1050 BC. Drawing from a range of searchable databases, we present the use of veterinary acupuncture related to theriogenology. We touch on human-based medicine only as an introduction to current uses within veterinary medical acupuncture. This review is confined to the use of acupuncture encompassing dry needle, electroacupuncture, aquapuncture, and the few reports of laserpuncture. Starting with acupuncture’s influence on the master organs of reproduction, the hypothalamus and the pituitary glands, and the hypothalamic–pituitary–gonadal axis, we then review reports specific to the gonads—ovaries and testicles—and then its influences on the uterus. From there, we review reports on the influence of acupuncture on pain associated with reproductive surgery, and finally, on the use of acupuncture for maternal lactation. Based on published reports, we conclude that acupuncture has been shown to be effective in many situations as a treatment for infertility and/or reproductive tract disfunction, resulting in improvements in both female and male patients.

The article presents a case study of a 16-year-old approximately Arabian stallion was examined because of an enlarged right side of the scrotum. It mentions ultrasonography of the right side of the scrotum revealed an increased volume of anechoic fluid around the right testicle, suggestive of a hydrocele. It also mentions differential diagnoses for the epididymal mass in the stallion of the present report are neoplasia, epididymal cyst, granuloma, and epididymitis.

Artificial insemination (AI) is widely used in livestock industries to breed for desirable characteristics and increase yields. The standard practice of storing and transporting bovine semen uses liquid nitrogen (LN), a scarce commodity in many regions of the world. This study explored the feasibility of using dry ice, a more readily available alternative. We developed equipment that dispenses dry ice from widely available liquid carbon dioxide (LCO2) tanks into an easily transportable device. In vivo fertility results with a dry ice cold chain showed no statistical difference to the conventional LN method. In vitro bovine semen analyses also showed that storage under these conditions minimally affects characteristics associated with fertility. A dry ice cold chain system could leverage the global availability of LCO2 to expand the reach of AI and other cold storage applications of biological materials in low-resource settings. [ABSTRACT FROM AUTHOR]

The article presents an answer to a question about differential diagnoses for colic in a periparturient mare.

The article presents a case study of a 7-year-old 570-kg multiparous warmblood mare that was an embryo transfer recipient of an embryo recovered from a donor mare 8 days after ovulation was referred for pregnancy assessment monitoring purposes. Topics include the pregnancy had been diagnosed with transrectal ultrasonography 14 days after embryo transfer, the fetus could not be palpated during rectal examination of the mare, and no further assessments had been performed since then.

The protozoan Tritrichomonas foetus causes early embryonic death in cattle, there are no legal options for treating this parasite in the United States, and there are few developed protocols for cleaning veterinary and obstetrical equipment that may have been contaminated with trophozoites. In this study, we evaluated bleach, ethanol, acetic acid, chlorhexidine gluconate, and hydrogen peroxide solutions for the ability to kill trophozoites in vitro . Our findings suggested that ethanol and bleach could adequately disinfect tools and equipment. Acetic acid, chlorhexidine, and hydrogen peroxide had applications as surface disinfectants in addition to potential as local topical treatments due to their past uses in veterinary theriogenology. Chlorhexidine gluconate demonstrated trophocidal effects by damaging parasite cell membranes and had the lowest effective concentration 50 (EC 50 ) of any compound tested and was in the micromolar range. These findings, in conjunction with accepted clinical uses of chlorhexidine gluconate suggest that this is a convenient agent for disinfecting equipment. In addition, topical use of chlorhexidine is relatively common, setting the stage for further investigation of this compound as a topical therapeutic option for bovine trichomonosis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Martin, Kovach, Moscoso, Carreiro, Jesudoss Chelladurai and Brewer.)

The Publisher regrets that this article is an accidental duplication of an article that has already been published in Theriogenology, 126C (1 March 2019) 303-309, http://dx.doi.org/10.1016/j.theriogenology.2018.12.025. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal [ABSTRACT FROM AUTHOR]

The article presents a case study related to 22-month-old Clydesdale filly was referred to the Purdue University Veterinary Teaching Hospital because of a 3-month history of an enlarged left mammary gland. Topics include the onset of enlargement during springtime, when juvenile galactorrhea in foals and yearling mares is more common, and the enlargement of the mammary gland persisted through the spring season.

The article presents a case study of a 10-year-old pregnant pluriparous Ragusano jenny presented for reluctance to move and inappetence. It informs that clinical examination revealed that the animal was depressed but in a good nutritional state. It also informs that the jenny was treated conservatively with stallrest and flunixin meglumine.

The article presents a case study related to 3-year-old has sexually intact female Golden Retriever has presented to the University of Georgia Veterinary Teaching hospital. Topics include the single assessment of its serum progesterone concentration has performed, the animals had vaccination and deworming status on the basis of negative results for card agglutination tests being free of canine brucellosis, and the owner has reported that there had been no complications during gestation.

The article describes the case of a male alpaca with enlargement of the right testicle which could be caused by seminoma, spermatocele, Sertoli cell tumor, Leydig cell tumor and teratoma. Topics discussed include procedure for the castration of the alpaca, size of the enlarged right testicle, and explanation on the occurrence of testicular neoplasia in camelids.

Objective: The objectives of this study were to evaluate the prevalence of chronic Anaplasma marginale infection in beef bulls from eastern Kansas and compare breeding soundness parameters between A marginale-infected and uninfected bulls. We hypothesized that bulls with chronic anaplasmosis would have inferior breeding soundness exam (BSE) outcomes as a result of persistent A marginale infection or the consequence of initial clinical disease compared to uninfected bulls., Animals: 535 client-owned beef bulls from eastern Kansas undergoing routine BSE., Methods: Complete BSEs were conducted by participating veterinarians according to the second edition of the Society for Theriogenology Manual for Breeding Soundness Examination of Bulls. Blood samples were collected for PCV determination and analysis of A marginale infection status via quantitative PCR and cELISA. Logistic and linear regression methods were used to evaluate factors associated with A marginale infection status and BSE parameters., Results: Prevalence of chronic A marginale infection was 46% (245/535) among bulls. Unsatisfactory BSE outcome was not statistically associated with chronic anaplasmosis in this study population, although more bulls with chronic anaplasmosis had unsatisfactory BSE outcomes (15.0 ± 2.4% vs 12.0 ± 2.2%)., Clinical Relevance: Chronic anaplasmosis is prevalent among eastern Kansas breeding bulls; however, no negative association between chronic anaplasmosis and breeding soundness at time of BSE was observed.

The seal tapeworm Diphyllobothrium tetrapterum (von Siebold, 1848) Baer, 1932 (syn. Diplogonoporus tetrapterus) is exceptional among cestodes because it possesses two types of the strobila, one with a multiple set of genitalia per proglottid and another with a single set of reproductive organs per proglottid. In this study, Diph. tetrapterum is redescribed on the basis of extensive, well-fixed material from the northern fur seal ( Callorhinus ursinus (Linnaeus, 1758)) from Alaska, USA. A critical morphological and molecular study of comprehensive material from several hosts throughout the Northern Hemisphere is provided. As a result, Diplogonoporus mutabilis Belopolskaia, 1960 and Diplogonoporus violettae Yurakhno, 1986 become junior synonyms of Diph. tetrapterum. Our study provides evidence of intraspecific and even individual variability of Diph. tetrapterum in the number of genital complexes, thus making this generic feature questionable for circumscription of the diphyllobothriid genera. The seal tapeworm has been found exclusively in the Northern Hemisphere and exhibits a wide (euryxenous) specificity at the level of the definitive host, having been found in a number of seals, the sea otter ( Enhydra lutris (Linnaeus, 1758)), and exceptionally, in other terrestrial mammals. Plerocercoids of Diph. tetrapterum are reported from the second (fish) intermediate host for the first time, in this case the pink salmon ( Oncorhynchus gorbuscha (Walbaum, 1792)) from Alaska. [ABSTRACT FROM AUTHOR]

Observations were made on follicle dynamics and gonadotropin concentrations in anovulatory wave 2 and ovulatory wave 3 in three-wave interovulatory intervals (n = 15). Hypotheses were not used owing to inadequate availability of rationale. The future dominant follicles for waves 2 and 3 were designated DF2 and DF3 and the largest future subordinate follicles as SF2 and SF3, respectively. The day of expected diameter deviation (day 0) was defined as the day that DF2 or DF3 was closest to 8.5 mm. The first day that DF2 became smaller (P < 0.05) than DF3 was day 2 (10.7 ± 0.2 mm vs 11.8 ± 0.3 mm). The FSH surges 2 and 3 that stimulated waves 2 and 3 were similar at peak concentration, but the postsurge nadir of surge 2 occurred 1 day earlier than for surge 3. An LH increase was not temporally associated with deviation in wave 2, but an increase (P < 0.05) in LH in wave 3 began on day −1. Diameter of SF2 (6.5 ± 0.2 mm) on day 0 was less (P < 0.005) than for SF3 (7.2 ± 0.2 mm). Mean diameter of subordinate follicles in wave 2 did not differ among days. Diameter of subordinate follicles that attained ≥6 mm in wave 3 was greater (interaction, P < 0.02) by day 3 when in the right ovary (RO, 7.4 ± 0.2 mm) than when in the left ovary (LO, 5.6 ± 0.2 mm). The frequency of a conventional classification of deviation (future SF greater than 7.0 mm on day 0) was less (P < 0.001) for wave 2 (1 of 15 waves) than for wave 3 (8 of 15 waves). Novel observations involving DF2 and DF3 were (1) before deviation, diameter of DF2 vs DF3 and an incline in FSH surge 2 vs surge 3 were similar and (2) after deviation, smaller diameter of DF2 vs DF3 by day 2 was associated with an earlier cessation (nadir) in FSH surge 2 vs surge 3 and an absence of an LH increase during deviation. Novel observations involving subordinate follicles ≥6 mm were (1) before deviation, diameters were similar between waves 2 and 3 in association with the similar incline in FSH surges 2 vs 3 and (2) after deviation, a greater diameter increase of subordinates occurred in RO than in LO for wave 3, but an increase did not occur for either ovary in wave 2. The characteristics of diameter deviation were profoundly different between waves 2 and 3 owing to a smaller SF2 than SF3 at deviation but similar diameter of DF2 and DF3. [ABSTRACT FROM AUTHOR]

Breeding records were analyzed from 24 Thoroughbred stallions that were subjected to dual-hemisphere breeding (DH), including novice (first-year; NOV; n = 11) and experienced (EXP; n = 13) stallions. Fertility variables included seasonal pregnancy rate, pregnancy rate per cycle, and first-cycle pregnancy rate. In addition, values for book size, total number of covers, distribution of mare type (maiden, foaling, and barren) within a stallion's book, cycles per mare, and mare age were examined. Some data were also categorized by mare type (maiden-M, foaling-F, and barren-B). Five separate analyses of the data were performed. For Analyses 1–3, the effects of hemisphere (northern hemisphere [NH] vs. southern hemisphere [SH]) and breeding order (refers to the first [O1] or second [O2] season within the first year of dual-hemisphere breeding) were examined for all stallions (combined group [CG]), NOV stallions only, and EXP stallions only, respectively. Fertility values were generally higher in the SH than the NH (P < 0.05), whereas book size, total number of covers, and cycles per mare were higher in the NH than the SH (P < 0.05). Book size and total covers were negatively correlated to first cycle pregnancy rate (r = −0.57, r = −0.71, respectively; P < 0.05) for NOV stallions. Pregnancy rate per cycle was also negatively correlated with total covers (r = −0.58; P < 0.05) for NOV stallions. Similar trends were noted for Groups CG and EXP, but the relationship was not as marked as for NOV stallions. The fertility of O1 was generally similar to O2 (P > 0.05). For Analysis 4, fertility of DH breeding seasons was compared to single hemisphere (SIN) breeding seasons within the same 16 stallions and was found to be similar between the two groups (P > 0.05). For Analysis 5, the effect of the number of consecutive DH breeding seasons on fertility was examined and was found to remain unchanged (P > 0.05). In summary, no adverse effects of DH breeding on fertility were detected. Fertility was higher when stallions were bred in the SH, as compared to the NH. Potential reasons for higher fertility achieved in the SH were smaller book sizes and better mare reproductive quality. [ABSTRACT FROM AUTHOR]

In this study, the Authors investigated the modulatory effect of three single doses (10 −6 , 10 −5 , and 10 −4 M) of neostigmine on the spontaneous contractility of equine pre-ovulatory follicles in an isolated organ bath, to establish the relationship between this acetylcholinesterase inhibitor and ovulation, in the mare. The results indicate that neostigmine increases pre-ovulatory contractility in equine follicles at each dose, but in a different manner. Indeed, the rise in contractility induced by neostigmine at 10 −6 M and 10 −4 M was phasic, while at 10 −5 M it was tonic. The data obtained indicate possible implications of these drugs in the pharmacological modulation of equine ovulation. [ABSTRACT FROM AUTHOR]