Breeding Soundness Examination Research Articles

Pharmacokinetics of florfenicol in serum and seminal plasma in beef bulls

The objectives of this study were to compare the serum and seminal plasma pharmacokinetic profiles of florfenicol (FLO) and florfenicol amine (FLA) after the administration of FLO either by IM or SC routes in beef bulls. Four clinically healthy Hereford bulls underwent a comprehensive physical exam, including breeding soundness examination, CBC, and chemistry profile panel. Bulls were healthy and classified satisfactory potential breeders. In one group (n = 2), a single dose of FLO was administered SC in the middle of the neck at a dose of 40 mg/kg of body weight. In the second group (n = 2), a single dose was administered IM in the muscles of the neck at a dose of 20 mg/kg. Concentrations of FLO and FLA in serum and seminal plasma were determined by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Blood and semen samples were collected before the administration of FLO and at 12, 24, 36, 48, 72, 96, 120, 144, and 168 h after injection. The blood was collected from the coccygeal vessels, and semen was collected by electroejaculation. All samples were immediately refrigerated, processed within the first hour after collection, and finally stored at −80 °C. The mean level of total FLO in serum was higher when administered by the SC route (1,415.5 ng/mL) than by the IM route (752.4 ng/mL; P = 0.001). Differences were observed between the percentage of FLA in serum (1.8%; ranging from 1.3 to 2.9) and in seminal plasma (27.5%; ranging from 15.9 to 34.2; P = 0.0001). The mean level (±SD) of FLA was higher in seminal plasma compared to serum (467 ± 466 ng/mL and 18 ± 16 ng/mL, respectively; P = 0.001). The mean level of total FLO in seminal plasma was 1,454.8 ng/mL for the SC route and 1,872.9 ng/mL for the IM route without differences between the two routes (P = 0.51). Differences in the mean level of total FLO between serum and seminal plasma were detected (1,187 ± 2,069 ng/mL and 1,748 ± 1,906 ng/mL, respectively; P = 0.04). From the present investigation, it was concluded that FLO is a suitable antibiotic based on its pharmacokinetic attributes and may be employed for the treatment of bull genital infections when its use is indicated. To study the pharmacokinetics of FLO in seminal plasma, the analysis of FLA should be incorporated.

Bull Breeding Soundness Assessment Using Artificial Neural Network-Based Predictive Models

For years, efforts have been devoted to establishing an effective bull breeding soundness evaluation procedure; usual research on this subject is based on bull breeding soundness examination (BBSE) methodologies, which have significant limitations in terms of their evaluation procedure, such as their high cost, time consumption, and administrative difficulty, as well as a lack of diagnostic laboratories equipped to handle the more difficult cases. This research focused on the creation of a prediction model to supplement and/or improve the BBSE approach through the study of two algorithms, namely, clustering and artificial neural networks (ANNs), to find the optimum machine learning (ML) approach for our application, with an emphasis on data categorization accuracy. This tool was designed to assist veterinary medicine and farmers in identifying key factors and increasing certainty in their decision-making during the selection of bulls for breeding purposes, providing data from a limited number of factors generated from a deep pairing study of bulls. Zebu, European, and crossbred bulls were the general groupings. The data utilized in the model’s creation (N = 359) considered five variables that influence improvement decisions. This approach enhanced decision-making by 12% compared to traditional breeding bull management. ANN obtained an accuracy of 90%, with precision rates of 97% for satisfactory, 92% for unsatisfactory, and 85% for bad. These results indicate that the proposed method can be considered an effective alternative for innovative decision-making in traditional BBSE.

Protamine 2 and phospholipase C zeta 1 are possible biomarkers for the diagnosis of male subfertility in frozen-thawed stallion semen

Subfertility is one of the main issues in horse breeding and the study of mRNAs in sperm might help in elucidating the reasons that lead to this diagnosis. The present study aims at assessing the differences in the expression of 10 potential candidate genes in stallions of different fertility. Frozen-thawed semen of 29 stallions was included. Each sample was classified into two groups according to pregnancy rates (PR) achieved with this semen: “good fertility” (GF; n = 17; PR ≥ 30 %) or “poor fertility” (PF; n = 12; PR <20 %). All stallions underwent a breeding soundness examination (BSE) before semen production and were only included into the semen cryopreservation program when raw semen characteristics at BSE met minimal requirements. Semen was cryopreserved following European Union regulations and all stallions met the respective health requirements. Each sample was assessed for concentration (NucleoCounter SP-100), motility (CASA), membrane functionality (SYBR-14/PI), mitochondrial membrane potential (JC-1), morphology (SpermacStain), acrosome integrity (SpermacStain), membrane integrity (HOS test) and chromatin integrity (Aniline blue). Sperm RNAs were extracted using the Direct-zol RNA Miniprep Kit (Zymo Research) and RT-qPCR was performed for each target gene. ACTB and RPL32 were included as reference genes (RGs) for normalization. For each variable of each group, mean, standard deviation and SEM were calculated. The difference in gene expression levels between the GF and PF group were analyzed using the Mann-Whitney U test and Spearman's rank correlation. Significant results were considered with p < 0.05. Sperm quality parameters did not differ significantly between the two groups except for concentration, that was significantly higher in GF (p = 0.043). In GF a positive correlation was identified for PRM1/PRM2 with r = +0.6, while PRM1/ACR (r = −0.495), PRM2/ZPBP (r = −0.645) and CRISP3/ACR (r = −0.551) were inversely correlated. In PF direct correlations were registered for PRM1/PRM2 (r = +0.629), PRM1/PRM3 (r = +0.657), PRM2/SPA17 (r = +0.685), SPA17/PLCZ1 (r = +0.786) and PRM3/ACR (r = +0.627). In the total sample (GF + PF), positive correlations were detected for PRM1/PRM2 (r = +0.625), PRM1/PRM3 (r = +0.368); PRM2/SPA17 (r = +0.465), SPA17/PLCZ1 (r = +0.637) and PLCZ1/ZAN (r = +0.587). Only two of the genes considered were differentially expressed in the 2 groups: PRM2 and PLCZ1, that were significantly (p < 0.05) overexpressed in the GF group. Stallions frozen-thawed semen with higher expression levels of PRM2 and PLCZ1 are more likely to belong to animals with a good pregnancy rate. Further studies are needed to investigate the role of sperm transcripts in male subfertility in stallions.

Age-related changes in hormonal profiles and testicular diameter of West African Dwarf buck treated with gonadotropin-releasing hormone

This study aimed to investigate the impact of age-related peripheral and Gonadotropin Releasing Hormone (GnRH) -stimulated hormonal profiles on testicular size in West African dwarf bucks. Twelve 3-month-old bucks were randomly divided into two groups: the GnRH- treated group (n = 6) and the control group (n = 6). Over the course of 10 months, from month 3 to month 12, the testicular diameter of all bucks was measured monthly, and blood samples were collected monthly for hormone analysis. The results showed that testicular diameter increased with age and higher concentrations of Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH) and Testosterone (T). The GnRHtreated group reached its peak testicular diameter (28.36±1.44 mm) earlier at 8 months compared to the control group (30.50±1.44 mm) at 10 months, aligning with the peak concentrations of FSH, LH, and T. While the GnRH stimulation led to higher FSH, LH, T, and estrogen levels in the treated group, it didn't significantly affect the final testicular diameter (p&lt;0.05). It can be concluded that hormonal levels rise with age and increasing testicular size, and GnRH stimulation can accelerate this process. Testicular size is an important factor in breeding soundness and is influenced by LH, FSH, and testosterone concentrations. These hormones can reliably indicate the reproductive capacity of the buck. Therefore, hormonal profiling should be an integral part of the breeding soundness examination.

PSII-7 Is Scrotal Ultrasound a Useful Tool in Ram Breeding Soundness examination?

Abstract Varicocele, a condition of abnormally dilated veins within the pampiniform plexus, is associated with reduced male fertility in several species but its frequency and impact in rams is not well documented. Semen was collected and pampiniform plexus ultrasound performed in early December during breeding soundness examinations (BSE) of mature Composite-IV rams over a three-year study. A portion of rams were evaluated in multiple years and data from a total of 129 collections on 90 rams were available for analyses. Semen parameters were estimated by computer-assisted sperm analysis (CASA). Imaging software was used to quantify the cross-sectional area of five vessels per testis and average areas of the left testis (AAL), right testis (AAR), and both testes (AAT) were calculated. The correlation between AAL and AAR measured on the same ram within a year was moderate and positive (0.51; P &amp;lt; 0.001). However, correlations between AAL, AAR, and AAT measured on the same ram in consecutive years were not different from zero. Average vessel area was analyzed with fixed effects of testis side (AAL or AAR), year (2020, 2021, or 2022), ram age (2, 3, or ≥ 4 yr-old) and a random effect of ram. Across years, AAL was 23 to 25% greater than AAR and 16 to 18% greater in ≥ 4-yr-old than younger rams (P &amp;lt; 0.01). Unilateral varicocele (UV) was diagnosed when AAL/AAR or AAR/AAL ratio exceeded 1.5 in a ram and, for rams sampled in multiple years, those diagnosed in one year were considered affected for all subsequent years. Within year, prevalence of UV ranged from 16 to 36%. Scrotal circumference (SC) and CASA parameters were analyzed with fixed effects of year, ram age, and UV status and a random effect of ram. Within 2- and 3-yr-olds, sperm from UV rams had lower motility than unaffected rams (42.1 ± 6.7% vs 62.2 ± 4.1% and 47.8 ± 7.4% vs 70.1 ± 4.7%, respectively; P ≤ 0.02) but no differences were observed within 4-yr-old rams. Across ages, sperm from UV rams had a lower percentage of normal than unaffected rams (91.5 ± 1.1% vs 94.3 ± 0.74%; P = 0.03). Sperm concentration, progressive motility, and SC were unaffected by UV status. Future studies will evaluate the effect UV status on siring capacity. Ultrasound methodologies previously refined to diagnose varicocele in boars helped identify sub-fertile rams that would not have been classified by routine BSE procedures. However, these methodologies would benefit from concurrent machine learning and software development to ensure imaging consistency across technicians and streamline procedures for real-time decision making. USDA is an equal opportunity provider and employer.

PSXIV-13 Evaluation of On-Animal Sensors for Monitoring Diurnal Physical Activity of Beef Bulls During the Breeding Season

Abstract Applications of on-animal sensors (OAS), commonly used to monitor behavioral patterns in livestock, remain largely undeveloped for extensively managed beef bulls. Thus, the objective of this study was to characterize and compare two OAS types for monitoring bull activity during the breeding season. Angus and Angus crossbred beef bulls (n = 50) aged 1 to 8 years, from six cow-calf operations in Ohio were placed into multi-sire breeding groups (n = 19) with a bull-to-female ratio of 1:25 (range 1:16 to 1:31). Bulls were placed with a female group from day 10 (range day 5 to 12) until day 60 after fixed-time artificial insemination. Before turnout, each bull was subjected to a breeding soundness examination and fitted with a collar-mounted GPS and an ear tag-mounted triaxial accelerometer (AX3). Raw GPS and AX3 activity measurements, namely speed (m/s) and motion intensity (g), were converted to standardized Z-scores and summarized to an hourly resolution by computing the median hourly activity over a 24-hour cycle at early (day 13 to 28) and late (day 34 to 49) stages of the breeding season. Linear mixed models were fitted to standardized activity measurements (expressed in log scale) to assess the dynamic effect of OAS type throughout the day at early and late stages of the breeding season. Size of the breeding group (males and females), bull age, scrotal circumference, and body condition score were evaluated as potential explanatory covariates using stepwise selection. Diurnal activity curves followed a pattern of relative inactivity overnight from hours 21 to 5 and relative activity during daylight from hours 6 to 20. For both OAS, mean activity early in the breeding season was ~47% greater (P &amp;lt; 0.01) than late. At both breeding season stages, mean activity of bulls differed between OAS types (P &amp;lt; 0.01) at hours 2, 3, 4, 5, and 6 by at least 38%, with greater activity from GPS than AX3 (P &amp;lt; 0.05 in all cases). Conversely, at hours 13, 14, and 16, activity derived from AX3 was greater than from GPS by at least 2.5-fold (14: P &amp;lt; 0.01; 13 and 16: P &amp;lt; 0.1). There was no evidence (P &amp;gt; 0.1) for differences between bull activity derived from GPS or AX3 during the remaining overnight (21-1) and daytime (7 to 12, 15, and 17 to 20) hours. In conclusion, this study provides evidence that simultaneous assessment of bull activity using independent OAS, differed between technologies throughout a 24-h day. Additionally, over the course of the breeding season, both OAS indicated a decline in activity. Bull breeding activities are expected to be less frequent as the breeding season progresses; thus, these may explain the observed differences between stages of the breeding season. Further exploration of benchmarks for bull activity may yield useful tools for the identification of health and reproductive-related behaviors.

Kansas beef bulls with chronic anaplasmosis demonstrate satisfactory breeding soundness outcomes at breeding soundness examination.

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. 535 client-owned beef bulls from eastern Kansas undergoing routine BSE. 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. 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%). 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.

Effect of the GnRH stimulation test on Canine Prostatic-Specific Esterase (CPSE).

The gonadotropin-releasing hormone (GnRH) stimulation test is used to investigate testicular production of testosterone (T) when performing a breeding soundness examination. In male dogs with fertility problems, the prostate should also be investigated as prostatic conditions may frequently lower semen quality. Serum concentrations of canine prostatic-specific esterase (CPSE) increase in dogs with benign prostatic hyperplasia (BPH). When performing a breeding soundness examination in a male dog, GnRH administration is frequently done at the beginning of the process and then both T and CPSE are assayed on the same serum sample collected 1 h following the GnRH injection. The aim of this study was to assess whether or not the administration of GnRH may alter CPSE concentrations in dogs with a healthy prostate. Twenty-eight client-owned intact adult male dogs were included in the study. Following a 7-day sexual rest all male dogs underwent a clinical examination and an ultrasonographic examination of the prostatic gland. Prostatic size and parenchyma of every tested dog were evaluated by ultrasonography to assess prostatic conditions. Two different GnRH stimulation protocols were used, A = gonadorelin 50μg/dog SC (n = 15) and B = buserelin 0.12 μg/kg IV (n = 13). T and CPSE concentrations were measured before and 1 h after GnRH administration by a laser-induced fluorescence analysis. Buserelin and gonadorelin were equally effective in causing a significant increase in serum T concentrations in the post GnRH sample. When considering the 28 dogs together, CPSE concentrations did not change following the stimulation test with either GnRH compound; however, in 4/28 cases, the post GnRH value was markedly increased to values compatible with a diagnosis of BPH. There was no difference in the action of buserelin or gonadorelin in causing an increase in serum T concentrations. CPSE secretion was increased in approximately 15% of dogs treated with either buserelin or gonadorelin. Therefore, whenever performing diagnostic testing in intact male dogs, CPSE should not be assayed on a post-GnRH serum sample.

Severe subfertility in Thoroughbred stallions positive for the Impaired Acrosome Reaction susceptible gene (FKBP6) in Argentina

Subfertility in stallions is one of the major causes of reproductive and economic loss in the equine industry. Low pregnancy rates have been reported in stallions with normal semen quality after conventional evaluation. Acrosome reaction (AR) is necessary for fertilization and impaired acrosome reaction (IAR) leads to subfertility or infertility in horses; however, the AR test is not included in routine semen analysis. Failure of AR may affect more than 90% of sperm, although the remaining sperm can perform normal AR during fertilization. Up to date, IAR has been confirmed as a cause of subfertility only in Thoroughbred stallions. A genome-wide association study identified FKBP6 as a strong candidate gene responsible for this failure. The gene encodes for FK506 binding protein 6 (FKBP6) which is involved in sperm development and function. The objective of this study was to evaluate the presence of IAR susceptibility genes in stallions with satisfactory breeding soundness examination (BSE) and acceptable semen parameters but a history of severe subfertility. Thoroughbred stallions (A, B and C), between 6 and 9 years old with satisfactory BSE but with a history of low pregnancy rates during the 2020 (stallion A = 11%) and 2021 breeding seasons (stallion A= 0%; stallion B= 29%; stallion C= 10%) were included. They were referred after several consultations, andrological examinations and non-specific treatments by differentveterinarians. Ejaculates of stallions A, B and C in DSO had the following values of total number of spermatozoa/ejaculate (4.6 × 109, 8.5 × 109, 6.7 × 109); progressive motility (40%, 60%, 60%); hypo-osmotic swelling test (73%, 60%, 72%); and normal sperm morphology (58%, 68%, 76%), respectively. Evaluation of acrosome status by FITC-PSA showed 12%, 84% and 20% intact acrosomes for stallion A, B and C, respectively. Based on history and results of BSE, hair samples of the three stallions were sent to Molecular Cytogenetics Laboratory, Texas A&M University, and all three stallions, tested positive for the IAR susceptibility gene (FKBP6). The IAR is associated with male subfertility in humans and some domestic species including horses. A/A-A/A genotype of FKBP6 gene is considered a susceptibility gene for IAR in thoroughbred stallions with idiopathic subfertility. Hernandez Aviles et al. (Theriogenology. 2022; 186, 40-49) reported a low prevalence (0.7%) of acrosomal dysfunction in the overall population of breeding stallions but a significantly higher rate (38.1%) in idiopathically subfertile stallions. New developments in equine genomics provide tools for mapping fertility traits and discover causes of subfertility by genetic defects. Therefore, we must consider this analysis within the andrological examination in stallions with idiopathic infertility.

Confocal laser endomicroscopic imaging of equine endometrium: evaluating image quality

A heathy uterus is a key piece of the fertility jigsaw and assessment of the endometrium is an essential component of the breeding soundness examination in mares. The current gold standard for evaluating uterine health is histopathological assessment of an endometrial biopsy. The Kenney-Doig (KD) grading scale is most used and scores both fibrotic and inflammatory changes present within the endometrium. The KD grade provides a prognostic indicator of the probability a mare can carry a pregnancy to full-term. Inconsistencies may arise when a single blinded biopsy is used, especially when uterine pathologic changes don't have a widespread distribution pattern. Confocal laser endomicroscopy (CLE) is a novel imaging modality that enables real-time in-vivo imaging of the endometrium. Multiple subcellular endometrial images (“virtual biopsies”) can be captured in quick succession in multiple locations within the uterine lumen noninvasively. Image depth in the z-axis can be controlled (0-100µm). Image quality was noted to be variable between mares in a previous pilot study (Gallacher.et.al. Journal of Equine Veterinary Science. 2018;66:106). The objective was to determine if physiological endometrial oedema present during oestrus has a negative effect on image quality. Twenty-four mares were examined with CLE (ViewnVivo, Optiscan, Australia) on two separate occasions, once during oestrus and once in dioestrus. A total of 4294 CLE images were captured, witha mean of 89.5 images saved per exam. A 4-point grading scale (1=poor and 4=excellent) was developed for quality assessment. A subset of ∼10 representative images from each of the 48 examinations were selected. Four examiners were blinded to the phase of the oestrous cycle and graded the images using the quality criteria assigned to the 4-point grading scale. An intraclass correlation (ICC) was estimated to determine reliability between the 4 scorers. The ICC coefficient was estimated using the irr package in R. Moderate agreement (ICCC(C,4) = 0.69) between scorers was observed while using the two-way random effect models and average rater where p<0.001. Quality data were analysed using a mixed model in asreml-R. The fixed factors included in the model were depth (1-luminal epithelium, 2-subluminal), cycle (oestrus and dioestrus) with brightness included as a covariate. Scorer and horse were included as random terms. There was a difference (p<0.001) between depth 1 and 2 (2.51 vs 2.71 respectively), and cycle (p<0.001) dioestrus = 2.71 oestrus = 2.51. The brightness of the image was also related to quality score (p<0.001) where a 100unit increase in brightness was associated with a reduction in quality score of ∼0.3. Image quality appears to be influenced by the phase of the oestrous cycle and this may guide the clinician to perform CLE examination during dioestrus.

Alternative Opportunities to Collect Semen and Sperm Cells for Ex Situ In Vitro Gene Conservation in Sheep

The semen of domestic mammals is conventionally collected with an artificial vagina (AV) for artificial insemination (AI) or for short- or long-term storage. However, the procedure has certain drawbacks: animal training is not feasible in extensive animal care systems nor among wild species, as the trained animals sometimes fail to mount. Hence, there is a need for alternative semen collection methods. Electroejaculation (EEJ) and epididymal sperm recovery (ESR) are the two effective alternatives to AV. However, in recent years, animal welfare campaigners have called for the ban, in certain EU countries, of EEJ due to its inhumane nature. In this review, alternative methods of sperm collection (by EEJ and ESR, their qualities, and their freezing techniques) are highlighted, as well as the effects of EEJ on pre-freeze and post-thaw ram sperm quality parameters and the animal welfare progress made in EEJ between the 20th and 21st centuries. Additionally, the techniques for enhancing post-thaw sperm quality prior to freezing and for the freezing of EEJ and ESR spermatozoa are explored. ESR and EEJ are reliable alternatives to AV on certain occasions. EEJ is ideal for semen collection in wild or untrained animals, breeding soundness examinations, collection outside of the breeding season, and culling. At the same time, ESR is ideal in cases of castration, accidental death of elite sire, or postmortem for gene conservation purposes or assisted reproductive technologies (ARTs) studies.

Satisfactory breeding potential is transiently eliminated in beef bulls with clinical anaplasmosis

BackgroundNatural service breeding is common in U.S. cow-calf operations. Diseases impacting bull reproductive performance have significant economic consequences for producers. Anaplasmosis may be an underappreciated cause of poor reproductive performance in bulls. The primary systemic effects of bovine anaplasmosis including anemia, fever, and weight loss, can all result in unsatisfactory reproductive performance. The objective of this pilot study was to evaluate breeding soundness examination (BSE) outcomes and clinical changes in bulls during and upon resolution of clinical anaplasmosis. Anaplasma marginale-challenged bulls were observed for clinical disease and infection progression and changes in breeding soundness compared to uninfected control bulls for 16 weeks.ResultsAll Anaplasma marginale-challenged bulls were PCR-positive, seropositive, and showed clinical signs by 3-, 17-, and 24-days post-challenge, respectively. Clinical signs of anaplasmosis included pallor, icterus, fever (≥ 40.2 °C), and weight loss. Acute anemia was observed in all challenged bulls with PCV nadirs ≤ 18% and peak percent parasitized erythrocyte ≥ 50%. Decreased scrotal circumference and poor semen quality (e.g., increased percentage of abnormal spermatozoa, decreased progressively motile sperm), were initially observed within days after onset of clinical anaplasmosis signs and continued weeks beyond disease resolution. Control bulls remained negative for A. marginale.ConclusionThis pilot study demonstrates that clinical anaplasmosis reduces breeding soundness in beef bulls. Anaplasmosis should be considered as a differential for bulls with decreased semen quality, especially within endemic areas. A 90 day or greater retest window is recommended for bulls of unsatisfactory breeding potential recently recovered from clinical anaplasmosis.

Breeding soundness examination in a clouded leopard

A 3-year male clouded leopard was presented to the University of Tennessee College of Veterinary Medicine Theriogenology servicesfor a breeding soundness examination. On physical examination, the left testis felt abnormally small. On ultrasonography,no abnormalities were observed; testis and prostate were of normal size. Semen was collected with a pulsator electroejaculatorand a ram electroejaculator probe (commonly used to collect semen in small ruminants). The purpose of using this electroejaculatorand probe was to determine if they could be used to collect semen from a clouded leopard. Using manual settings with thisdevice we collected ~ 0.2 - 0.3 ml of semen. Motility and morphology of sperm were acceptable. We concluded that the PulsatorIV electroejaculator and ram probe can be used to collect semen as part of breeding soundness evaluation in a clouded leopard.

Breeding soundness examination (BSE): a decision-making tool that requires a particular guideline for male goats.

Breeding soundness examination (BSE) is a common evaluation to predict the reproductive ability of male livestock. The generated guideline for BSE is specified for each animal species to enhance the performance of BSE. However, there is no particular BSE guideline for bucks yet; then, the BSE guidelines for ram and bull are commonly used for bucks. This investigation was conducted to determine the main BSE characteristics and the appropriate age range for assessment in Boer goats. For this purpose, semen was collected using electro-ejaculation, and seminogram variables (semen-BSE traits) were evaluated using conventional methods. The association between common testicular biometric variables (TBVs) and semen-BSE traits were assessed using Pearson's correlation coefficients and multiple linear regression. Logistic regression was used to test the validity of TBVs for the BSE of Boer goats. In this study, a strange appearance of the head of sperm, known as "rod-in-head" (RIH), was observed. The results showed that the appropriate age range for performing BSE in bucks is 12-30months. Moreover, scrotal length in the range of 10-15.9cm was the eligible TBV to be used as a predictor for semen-BSE traits. It was suggested that developing a BSE guideline for bucks is necessary for unbiased selection in performing BSE.

The role of impaired acrosomal exocytosis (IAE) in stallion subfertility: A retrospective analysis of the clinical condition, and an update on its diagnosis by high throughput technologies

Acrosomal dysfunction has been considered as a cause of subfertility in males of different species, including stallions. A subset of subfertile stallions with acrosomal dysfunction is unique because they have normal sperm quality (motility, morphology, viability, and DNA quality). The current work aims to describe the clinical characteristics of subfertile stallions that were diagnosed with Impaired Acrosomal Exocytosis (IAE) by using two high throughput methods: flow cytometry and molecular genetic analysis, and to identify the prevalence of subfertility due to IAE in stallions evaluated at Texas A&M University. Clinical data from 1,128 stallions evaluated during 17 years at a Veterinary Teaching Hospital was retrospectively analyzed. Only stallions with a history of subfertility not explained following a breeding soundness examination and/or conventional semen analysis, were included. For those stallions, the acrosomal exocytosis test (AE test), in which sperm is incubated at 37 °C for up to 2 h in the presence of the calcium ionophore A23187, was used to determine IAE. The difference in AE-Rate (AE-Diff) between each pair of fertile control stallion and subfertile stallion was categorized as: Normal: AE-Diff < 14%; Questionable: AE-Diff 15–29%; Abnormal: AE-Diff > 30%. In selected cases, blood or hair was procured for identification of the susceptibility genotype for IAE, A/A-A/A, in the FKBP6 gene, exon 5. Twenty-one (21) stallions (1.86% total population analyzed) had reduced fertility despite having acceptable sperm quality. Sperm from these stallions were subjected to the AE Test. Of these, 8 stallions had reduced sperm AE-rate, based on the AE Test (8/21; 38.1%). Subsequently, blood or hair samples from these 8 stallions which had either questionable (AE-Diff 15 – 29%; n = 5) or abnormal (AE-Diff > 30%; n = 3) responses to the AE Test were analyzed for the susceptibility genotype for IAE, A/A-A/A (FKBP6 gene, exon 5). Seven out of the eight (7/8) stallions carried this susceptibility genotype. All of these were Thoroughbreds. After 2 h of incubation, the viability in fertile stallion sperm was lower than in A/A-A/A stallions (4% vs. 25%, respectively; P < 0.05), while the AE-rate was higher for fertile than for A/A-A/A stallions (85% vs. 56%, respectively; P < 0.05). The use of two high throughput tests (i.e., flow cytometry and molecular genetic analysis) may complement each other in the diagnosis of IAE in breeding stallions. In this study, 5/7 subfertile stallions diagnosed with the IAE susceptibility genotype would have been diagnosed as normal with the AE Test. This study introduces a subset of stallions with the IAE genotype with fertility higher than has been previously reported (i.e., <15% per-cycle pregnancy rate), suggesting that IAE manifests as a broader range of subfertility.

Effect of lameness on breeding soundness examination results of beef bulls

Studies suggest that high cortisol resulting from lameness-associated pain decreases testosterone and disrupts spermatogenesis leading to decreased fertility. The objective of this study was to investigate the effect of lameness on cortisol and testosterone concentrations and breeding soundness examination of beef bulls presented to a veterinary teaching hospital. Bulls, two-years of age or older, that presented for lameness, foot trim, and/or breeding soundness examination were enrolled. Blood samples were collected for cortisol and testosterone evaluation. A complete breeding soundness examination (BSE) was performed in all bulls. Subsequently, a complete lameness examination was performed, and limb/foot lesions recorded. A blinded evaluator used a lameness score of 1–5 to classify each bull as lame (>1) or not-lame (1). A total of 60 bulls were enrolled (34 with a satisfactory BSE and 26 with an unsatisfactory BSE result). Cortisol and testosterone were not different between the unsatisfactory and satisfactory groups (P = 0.26 and 0.32, respectively). The most common limb/foot lesions found in the unsatisfactory and satisfactory groups were laminitis-related (61.50% and 41.20%, respectively). There was no difference in the proportion of lame and not-lame bulls in the unsatisfactory and satisfactory groups (P = 0.17). The odds of a satisfactory BSE result were 4.40 times higher in not-lame bulls when compared with lame bulls. Therefore, lameness is associated with an unsatisfactory BSE result in beef breeding bulls.

Normal feline reproduction: The tom.

Understanding the normal reproductive anatomy and physiology of the male cat is important for successful breeding. Veterinarians may be called in to troubleshoot when fertility and pregnancy rates decrease in a cattery. By understanding the normal physical parameters, as well as breeding behavior, the veterinarian is better equipped to assess the infertility issue. Also, clients are increasingly requesting breeding soundness examinations prior to mating or purchase. Semen collection is more difficult in the cat than in the dog but can still be accomplished in a clinical setting and provides important information when confronted with breeding males. The aim of this review is to provide a practical overview of the breeding male. The reader will receive information on time of puberty, normal reproductive anatomy (both external and internal), and breeding management practices to optimize fertility. The most up-to-date semen collection techniques are discussed, as are sedation/anesthesia options. Also, historical literature on the basic anatomy of the male reproductive system is reviewed, such as how the penile spines work and when they appear; this information is specific to the cat. The information in this article is based on the author's experience, as well as drawing on historical and current literature, and provides the most up-to-date review as possible.

The future of assessing bull fertility: Can the 'omics fields identify usable biomarkers?†.

Breeding soundness examinations for bulls rely heavily on the subjective, visual assessment of sperm motility and morphology. Although these criteria have the potential to identify infertile males, they cannot be used to guarantee fertility or provide information about varying degrees of bull fertility. Male factor fertility is complex, and the success of the male gamete is not necessarily realized until well after the spermatozoon enters the oocyte. This paper reviews our existing knowledge of the bull’s contribution from a standpoint of the sperm’s cargo and the impact that this can have on fertilization and the development of the embryo. There has been a plethora of recent research characterizing the many molecular attributes that can affect the functional competence of a spermatozoon. A better understanding of the molecular factors influencing fertilization and embryo development in cattle will lead to the identification of biomarkers for the selection of bulls of superior fertility, which will have major implications for livestock production. To see this improvement in reproductive performance, we believe incorporation of modern technology into breeding soundness examinations will be necessary—although many of the discussed technologies are not ready for large-scale field application. Each of the ‘omics fields discussed in this review have shown promise for the identification of biomarkers of fertility, with certain families of biomarkers appearing to be better suited to different evaluations throughout a bull’s lifetime. Further research is needed for the proposed biomarkers to be of diagnostic or predictive value.

Breeding Soundness Inspection and Production Features of Bullocks under Ecological Conditions in Free State Region, South Africa

Assessing the fertility of bullocks preceding to use as breeding animals make apparent economic if it were possible. Fertility is not possible predicted by means of a breeding soundness evaluation (BSE), but by the application of minimum standards to a set of accepted procedures, which supports informed decision makers to the breeding potential of the bullock. An bullocks found to satisfy these criteria in Central Performance Testing (CPT) known as Phase C, is reckoned to be breeding sound (BS). Furthermore, breeding success depends on the reproductive performance of both the cow and the bull. Breeding bull is likely to service a large number of heifers or cows in planned breeding season. The efficiency of a bullock can be based on the average daily gain (ADG) and feed conversion ratio (FCR) but poor breeding sound evaluation can be regarded as infertile. Bull breeding soundness evaluations (BSEs) are significant economic management of beef herd management and depends on adequate semen quality, physical soundness and serving capacity. Furthermore, assessment of scrotal circumference (SC), libido, testicular measurement and semen parameters often not done during a routine breeding soundness examination. The aim of this study was to depict using BSE whether bullocks would be fertile under Phase C. The relationship of BSE and production characteristics in central performance testing is challenging to identify fertility in bullocks within 112 given days of CPT. This study investigated performance data extracted from Integrated Registration and Genetic Information System (Intergis) managed by Agricultural Research Council Glen Bull Testing Centre. There were three breeds investigated, namely, Simmentaler, Santa Gertrudis and Limousin for the period of 2007 to 2017, were analysed to determine the dominance and importance of factors affecting breeding soundness classification.

Herd Structure and Incidence of Supernumerary Teats and Wattles in Smallholder Goat Production in Plateau State

A study was conducted to determine the incidences of supernumerary teat and wattles in goat and the relationship between the two traits. The survey was conducted with 104 farmers having 948 goats. Attributes measured were herd, herd size, male, female, coat colour, long hair back, long hair at the thigh, long hair back and thigh region, udder pigmentation, beard, dam, tassel, farmer’s experiences on supernumerary teat, and tassel. Data were analysed using descriptive statistics and correlation in J.M.P genomics software. There was presence of more female goats in the herds than males in Plateau State. The incidence of supernumerary teat was 31.6% in does while incidence of wattle tassel was 37.4 %. The colour of white, tan, brown and black were low in frequency (1.88, 2.64 and 9.28%). Normal hair was significantly and positively correlated with long hairs at the back was significantly and positively correlated with beard and tassel in the does (P˂ 0.01; r= 0.42- 0.43). Beardness in the does was only (12.48 %) with majority being non-beard (87.52 %). In conclusion, this has emphasized the need for breeding soundness examination including mammary gland to identify and eliminate supernumenary teat during during community based genetic improvement of goats. A programmed should be organised for farmers on supernumerary teat and wattle in goats and their managerial approach.