Post Castration Research Articles

Efficacy of a single central injection of lignocaine at the scrotal neck on the behavioural response of lambs to castration

ObjectiveTo compare the behavioural responses of lambs to ring castration with or without local anaesthetic administration by single midline injection at the scrotal neck. Study designBlinded, randomized block design pen study. AnimalsA group of 60 male Merino lambs; 6–8 weeks of age; average body weight of 18.5 ± 0.33 (mean ± standard error of the mean) kg at the time of castration. MethodsLambs were randomly assigned to three groups of 20: 1) NUMNUTS – lamb placed in a marking cradle and ring castrated with 1.5 mL lignocaine 2%; 2) SHAM – lamb placed in marking cradle and the scrotum manipulated as though an elastrator castration ring were applied; and 3) RING – lamb placed in the marking cradle, ring castration performed using an elastrator. Pain-related behaviours annotated for 1 full minute every 5 minutes post-procedure, from video footage collected for 2 hours post-procedure, according to a defined ethogram. ResultsLignocaine administration led to significant (p < 0.05) reductions in restless behaviour at 5 and 10 minutes in NUMNUTS lambs compared with RING (mean = 0.2 ± 0.4 versus 1.0 ± 0.4, respectively) post castration. A significant (p = 0.01) reduction in foot stamping and kicking behaviour at 5 minutes post castration (mean = 1.5 ± 0.4, for RING versus 0.4 ± 0.4 for NUMNUTS) and significant (p = 0.001) reduction in the sum of all acute pain-related behaviours at 5 minutes post castration. Conclusion and clinical relevanceA single midline injection of local anaesthetic at the scrotal neck can alleviate the behavioural responses to ring castration in the immediate post-procedure period. However, the duration of effect was limited, which may be a result of the drug we used. Development of a longer-lasting local anaesthetic formulation is imperative to optimize pain mitigation for ring castration.

Efficacy of inguinal buffered lidocaine and intranasal flunixin meglumine on mitigating physiological and behavioral responses to pain in castrated piglets.

Managing castration pain on US sow farms is hindered by the lack of Food and Drug Administration (FDA) approved products for mitigating pain. Previous work assessing flunixin meglumine (FM) efficacy in mitigating castration pain has shown the drug to be effective in pigs, meanwhile, results from previous work evaluating lidocaine efficacy are contradictory. Therefore, the objectives of this study were to determine the efficacy of inguinal buffered lidocaine (BL) and FM in mitigating castration pain in piglets. This study was divided into Part I (physiological response) and Part II (behavioral response). For part I piglets were randomly assigned to the following treatments: T1: (C) Castration plus physiological saline; T2: (S) Sham plus physiological saline; T3: (CL) Castration plus BL; T4: (SL) Sham plus BL; T5: (CF) Castration plus FM; T6: (SF) Sham plus FM; T7: (CLF) Castration plus BL and FM; T8: (SLF) Sham plus BL and FM. Blood was collected 24 h prior to castration, 1 h, and 24 h post castration for cortisol quantification. For Part II another cohort of piglets was enrolled and randomly assign to the following treatments: T1: (C) Castration plus physiological saline and T7: (CLF) Castration plus BL and FM. Behavior scoring was obtained in real-time by observing each piglet for 4-min continuously using Unesp-Botucatu pig acute pain scale (UPAPS) at the following timepoints: 1 h before castration (-1 h), immediately post-castration (0 h), and 3 h post-castration (+3 h). Average cortisol concentrations did not differ at -24 h (P > 0.05) or at 24 h post-castration (P > 0.05) between treatments. At 1 h post-castration, castrated piglets (C and CL) demonstrated greater cortisol concentrations (P < 0.05). Castrated piglets in the CF and CLF group had lower cortisol concentrations compared to C and CL-treated pigs (P < 0.05). For behavioral response, there were no differences between treatments on total UPAPS scores (C and CLF, P > 0.05). Intranasal FM was able to effectively reduce the physiological piglet's response immediately post-castration. Inguinal buffered lidocaine had no effect on the either physiological or behavioral response to pain. Long-term research should focus on refining injection techniques for inguinal BL and consider administration frequency and dosing of intranasal FM to control pain for a longer period post-castration.

Effect of sperm and glycerol concentration on epididymal sperm motility parameters after thawing

The aim of this study was to evaluate the effect of different glycerol concentrations and different sperm concentrations on stallion epididymal sperm motility indicators after thawing. For statistical analysis, 25 stallions were used. Collection of the epidydimal spermatozoa was performed as a retrograde flush of cauda epididymis and ductus deferens within 12 h post castration. After evaluation, the resuspended spermatozoa were centrifuged, the supernatant removed and the spermatozoa resuspended in Gent semen extender to get three different groups with different concentrations of sperm (250 × 106 in ml, 500 × 106 in ml, 1000 × 106 in ml) and different final glycerol concentrations (2%, 4%, and 6%). Therefore, 9 different samples were finally obtained from each stallion. The spermatozoa were packed and placed in a fridge (4 °C) for 2 h, then placed in liquid nitrogen vapour (−80 to −100 °C) and after 25 min plunged into the liquid nitrogen and stored at −196 °C for at least 5 days. The selected straws were individually thawed in a 38 °C water bath for 30 s prior to post-freezing analysis. Motility indicators were assessed at 0, 60, 120, and 180 min after thawing. Parametric test was used for analysis; the measured indicators were total motility, progressive motility, curvilinear velocity, straightness, and average-path velocity. In this study, the best results were reached in samples diluted into a concentration of 1,000 × 106 in ml, regardless of the concentrations of glycerol.

State and prospect of application immunocorrection therapy in castration of piglets and 5‐month‐old boars in pig breeding farm

One of the most widespread surgical interventions is the castration of piglets and 5‐month‐old boars without breeding selection being a criterion in conditions of intensive development of the pig breeding industry. This work aims to use immunocorrection therapy, methods and system of their use, technological simplicity, and efficiency in boars castration in the pig breeding industry.The research was done with the help of the pig breeding industrial complex and Kostroma State Agricultural Academy. 87 hybrid boars at the age of 5 months (F1) were used. In total, two cycles of experiments were carried out. For the first cycle, 49 animals were divided into 7 groups (n=7) to define the effectiveness of using different methods and schemes of immunocorrection therapy in post‐castration complications and its impact on product indicators. In the second cycle of the research, performance indicators of pig‐meat production were studied on the control group (n = 9) and experimental group (n = 29) of boars by using the best immunocorrection therapy according to the first cycle of the research.Thymogen injection is a synthetic immunomodulatory dipeptide, an analog of one of the thymus hormones. Ribav (mycovit) is a natural origin alcohol‐based drug for local use immunocorrectors. Both immunocorrectors were used for the research.Research results: decrease of complications with an open surgical way of castration in the experimental group on 28,57% (control group 57,14%) especially in the group treated with thymogen and Ribav in post castration time; similar results were received considering local reactions as hyperemia and less edema; the same indicators were higher than in the control group at the closed technique of castration. It can be caused by an immune reaction to suture material ‐ Polycon; Ribav was more effective at the open technique of castration than at closed, which is explained by the accessibility of local wound treatment; the average daily gain in live weight in the groups treated with thymogen and Ribav was 0.551 ± 0.13 and 0.618 ± 0.09 versus 0.406 ± 0.04 kg in control, meat yield rate 77.0 ± 0.58 and 76.40 ± 0, 29 versus 76.85 ± 0.14 in control with 85.71% safety in the experimental groups versus 81.43% in control.Thus, Thymogen is preferable according to its manufacturability and cost indicators.In the second cycle of experiments with its use, the gain in live weight exceeded the indicators of the control group by 18.6% without significant differences in meat on the bone and its yield. At the same time, it should be noted that the safety of the livestock, as in the first series of experiments, was 7.6% higher in the experimental group (96.55 versus 88.89%).Thus, thymogen post castration injections or Ribav (mukovit) local irrigation treatment with a five‐day course at a postoperative period reduce the risk of post castration complications on 14,28 ‒ 28,57% in the condition of pig breeding intensification, reduce emersion of local reactions, increases the safety among 5‐month‐old boars by 14.28 ‐ 28.57%.As a result, it is better to use treatment schemes based on using Ribave with the closed technique of castration on small pig farms when personal care is possible.

Abstract 81: Trop2 regulates prostate cancer growth and metastasis through distinct molecular mechanisms

Abstract Background: The first line of treatment for men with advanced prostate cancer is androgen deprivation therapy. Although initial responses are observed, prostate cancer commonly relapses in its lethal metastatic form referred to as castration resistant prostate cancer (CRPC) with 1-2 years mean survival time. Neuroendocrine prostate cancer (NEPC) is highly aggressive, AR independent subtype and usually emerges post castration resistance. We recently identified that the cell surface receptor, Trop2, is a new driver of NEPC. Moreover, we demonstrated that Trop2 regulates prostate cancer growth and metastasis. In this study, we set out to delineate the molecular mechanisms through which Trop2 regulates prostate cancer growth and metastasis. Methods: Proximity-dependent Biotin Identification (BioID) followed by mass spectrometry was performed to identify Trop2 interactome. Lentiviral infection was used to generate prostate cancer cell lines with over-expression of Trop2 and knock-down of NOTCH1, SLC4A7, PLEC, and OCLN shRNA to modulate gene expression levels. In vitro functional assays were performed including colony formation, and Matrigel drop 3D cell invasion assays. Results: The Trop2 membrane interactome was identified utilizing Proximity-dependent Biotin Identification (BioID) in living cells and uncovered that Trop2-mediated prostate cancer growth and metastasis are orchestrated by distinct downstream pathways including Notch signaling (NOTCH1), control of intracellular pH (SLC4A7), exosome secretion (PLEC), and tight junctions (OCLN). Interaction of Trop2 binding partners including NOTCH1, SLC4A7, PLEC and OCLN with Trop2 were further validated by fluorescence resonance energy transfer (FRET) using confocal microscopy. Moreover, knocking down the Trop2 interacting partners in Trop2 over-expressing prostate cancer cells suppressed Trop2-driven growth and invasion ability. Conclusions: In a previous study, we identified cell surface receptor, Trop2, as a novel driver of metastatic NEPC. Herein, our new findings reveal that Trop2 interacts with NOTCH1, SLC4A7, PLEC, and OCLN, which may highlight novel biological functions of Trop2 in prostate tumorigenesis and provide new understanding of the potential mechanism of neuroendocrine differentiation and metastasis to provide new therapeutic strategy for metastatic CRPC with neuroendocrine features. Citation Format: Tanya Ivanova Stoyanova, En-Chi Hsu, Shiqin Liu, Fernando Jose Garcia Marques, Abel Bermudez, Merve Aslan, Michelle Shen, Sharon Pitteri, James D. Brooks. Trop2 regulates prostate cancer growth and metastasis through distinct molecular mechanisms [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 81.

Trop2 regulates prostate cancer growth and metastasis through distinct molecular mechanisms

Background Prostate cancer is the most common non-cutaneous cancer and second leading cause of cancer related deaths in men in the United States. The first line of treatment for men with advanced prostate cancer is androgen deprivation therapy. Although initial responses are observed, prostate cancer commonly relapses in its lethal metastatic form referred to as castration resistant prostate cancer (CRPC) with 1-2 years mean survival time. Neuroendocrine prostate cancer (NEPC) is highly aggressive, AR independent subtype and usually emerges post castration resistance. We recently identified that the cell surface receptor, Trop2, is a new driver of NEPC. Moreover, we demonstrated that Trop2 regulates prostate cancer growth and metastasis. In this study, we set out to delineate the molecular mechanisms through which Trop2 regulates prostate cancer growth and metastasis. Methods Proximity-dependent Biotin Identification (BioID) followed by mass spectrometry was performed to identify Trop2 interactome. Lentiviral infection was used to generate prostate cancer cell lines with over-expression of Trop2 and knock-down of NOTCH1, SLC4A7, PLEC, and OCLN shRNA to modulate gene expression levels.In vitro functional assays were performed includingcolony formation, and Matrigel drop 3D cell invasion assays. Results The Trop2 membrane interactome was identified utilizing Proximity-dependent Biotin Identification (BioID) in living cells and uncovered that Trop2-mediated prostate cancer growth and metastasis are orchestrated by distinct downstream pathways including Notch signaling (NOTCH1), control of intracellular pH (SLC4A7), exosome secretion (PLEC), and tight junctions (OCLN). Interaction of Trop2 binding partners including NOTCH1, SLC4A7, PLEC and OCLN with Trop2 were further validated by fluorescence resonance energy transfer (FRET) using confocal microscopy. Moreover, knocking down the Trop2 interacting partners in Trop2 over-expressing prostate cancer cells suppressed Trop2-driven growth and invasion ability. Conclusions In a previous study, we identified cell surface receptor, Trop2, as a novel driver of metastatic NEPC. Herein, our new findings reveal that Trop2 interacts with NOTCH1, SLC4A7, PLEC, and OCLN, which may highlight novel biological functions of Trop2 in prostate tumorigenesis and provide new understanding of the potential mechanism of neuroendocrine differentiation and metastasis to provide new therapeutic strategy for metastatic CRPC with neuroendocrine features.

Expression of ISL1 and its partners in prostate cancer progression and neuroendocrine differentiation.

ISL1 serves as a biomarker of metastasis and neuroendocrine neoplasia in multiple tumors. However, the expression and relation of ISL1 to other biomarkers in prostate cancer have not been fully elucidated. Here, we characterize the expression ofISL1 and its partners in PCa and document its association to disease progression and post castration resistance neuroendocrine differentiation. The expression of ISL1 was interrogated in > 6000 primary samples from the Decipher GRID registry and 250 mCRPC samples to assess its prognostic value and relation to neuroendocrine differentiation. ISL1 was highly correlated to MEIS genes and other genes related to cell motility. ISL1 down-regulation in PCa was associated with cancer progression, aggressive primary tumors, and metastatic outcome. We found that ISL1 is highly correlated to MEIS genes across multiple primary PCa and mCRPC cohorts. The expression of ISL1 and MEIS genes were significantly and inversely related to metastasis-free survival and lethal disease, and were downregulated in CRPC and hormone naïve metastatic tumors but showed upregulation in neuroendocrine tumors. Co-immunoprecipitation showed MEIS2 and ISL1 interacting with each supporting their role in modulating transcriptional regulation and nominating this complex for potential targeted therapy. ISL1 complex with MEIS2 serves a critical role in prostate tumor progression and its upregulation in mCRPC/NE provides a rationale for assessing the role of ISL1 and its associated protein in treatment resistance.

Determinación de la edad propicia para la gonadectomía en pollos criollos

The objective of the research was to improve the productive parameters in Creole chickens through gonadectomy in the Tungurahua Province, Ecuador. A completely randomized design with three treatments and a control was used, the results were subjected to an analysis of variance (ADEVA) for the separation of means and the Tukey test of 5%, the factors under study were: T1 (8), T2 (9) and T3 (10), castrated weeks of age, and uncastrated chickens (20 birds / treatment), with a productive period after castration of 12 weeks. Weight gain 12 weeks after castration was higher in chickens operated on at 8 weeks of age, (343.6 g bird / week, p <0.05). The lowest feed consumption was in week 3 post castration (p <0.05). Roosters castrated at 8 and 9 weeks had better feed con-version (6.33 and 6.53, respectively) (p <0.05). Carcass yield was higher in castrated roosters compared to the uncastrated control group (p <0.01). The mortality. It was better in T1 (8 weeks old) with 0%. For this reason, the application of the surgical technique performed at of age is the most recommended.

Abstract 2026: Loss of fibroblasts-dependent androgen receptor activation in prostate cancer cells develops castration-resistant prostate cancer

Abstract Well-differentiated prostate cancer (PCa) cells are generally androgen/androgen receptor (AR)-dependent, i.e. AR signaling regulates cell cycle and differentiation. Loss of AR signaling after androgen deprivation therapy (ADT) triggers AR-independent outgrowth, generating poorly differentiated uncontrollable PCa cells. To prevent development and progression of castration-resistant prostate cancer (CRPC), we hypothesize that preservation of AR signaling after ADT is an important target. Tumor stroma surrounding PCa cells is enriched in fibroblasts secreting AR-activating factors, e.g. EGF, IGF1, and IL-6. Thus, we investigated the role of fibroblasts in AR activation of human prostate cancer LNCaP sublines differing in androgen sensitivity under androgen deprivation. Androgen-low-sensitive E9 and F10 cells were obtained from the parental androgen-sensitive LNCaP cell population through use of a limiting dilution method in regular culture condition. In contrast, androgen-insensitive AIDL cells were established from LNCaP cells by continuous passaging under hormone-depleted condition. Original fibroblasts pcPrFs (-M5, -M6, -M7) were isolated from needle biopsy samples of patients with PCa. The PCa cells alone or PCa cells plus pcPrF-M5 were grafted beneath the renal capsule of male athymic nude mice, and then mice were castrated on 14 days post transplantation. Tumor volume of E9 cells + pcPrF-M5 became diminished post castration but that of F10 and AIDL cells + pcPrF-M5 was gradually increased even post castration. In E9 cells + pcPrF-M5 tumors, serum PSA became detected on day 21 post castration. Interestingly, serum PSA was gradually increased even in F10 cells inoculated alone. In AIDL tumors with or without pcPrF-M5, serum PSA was not detected because of mutated AR in AIDL cells. Cell growth of E9 and AIDL cells was directly increased by treating with EGF, whereas that in F10 cells was not affected. Phosphorylation of AKT and ERK1/2 in E9 and AIDL cells was also significantly increased by treating with EGF, whereas that in F10 cells was not affected. In the condition of co-cultures with fibroblasts, PSA production was directly increased in E9 cells but not in F10 and AIDL cells. Protein expression of AR splice variant 7 (AR-V7) was only detected in F10 cells. The reduced AR-dependency of PCa cells is an important clinical development because of its association with the cell’ progression to CRPC. Here our results showed that fibroblasts secreting AR-activating factors preserved AR signaling in E9 cells after ADT, indicating that this type of PCa cells can be controlled by ADT. In contrast, we suggest that loss of fibroblasts-dependent AR activation in F10 and AIDL cells may be responsible for development and progression of CRPC. Citation Format: Kenichiro Ishii, Izumi Matsuoka, Takeshi Sasaki, Manabu Kato, Kohei Nishikawa, Hideki Kanda, Yoshifumi Hirokawa, Kazuhiro Iguchi, Kiminobu Arima, Masatoshi Watanabe, Yoshiki Sugimura. Loss of fibroblasts-dependent androgen receptor activation in prostate cancer cells develops castration-resistant prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2026.

Effect of Low Androgen Status on the Expression of P2Y Receptors in the Corpus Cavernosum of Rats

To determine whether low androgen status impacts erectile function by regulating the expression of the G protein-coupled P2Y receptors (P2Y1, P2Y2, P2Y4, and P2Y6) in the corpus cavernosum penis of rats. A total of 36 healthy, 8-week-old, male Sprague-Dawley rats were randomly allocated into 6 groups: 4 weeks of androgen replacement therapy post castration (group A); 4 weeks post castration (group B); 4 weeks post sham operation (group C); 8 weeks of androgen replacement therapy post castration (group D); 8 weeks post castration (group E); and 8 weeks post sham operation (group F). The ratio of maximum intracavernous pressure/mean arterial pressure was measured for every group and detected the expression of P2Y1, P2Y2, P2Y4, and P2Y6 in the rat corpus cavernosum penis of every group. The ratio of maximum intracavernous pressure/mean arterial pressure significantly declined in the castration group compared with the control group (P <.01). The expression of P2Y1, P2Y2, P2Y4, and P2Y6 and the ratio of the phosphorylated endothelial nitric oxide synthase (eNOS)/eNOS proteins were significantly lower in the castration group vs treatment or control (P <.01) whereas they were significantly lower in the group of 8 weeks vs 4 weeks post castration (P <.05). The rat serum testosterone levels in every group were positively correlated with the protein levels of P2Y1, P2Y2, P2Y4, and P2Y6. Downregulation of the expression of the P2Y1, P2Y2, P2Y4, and P2Y6 receptors that reduces the ratio of phosphorylated eNOS/eNOS and eNOS activity may be one of the important mechanisms of erectile dysfunction caused by low androgen status.

EFEITOS DA CASTRAÇÃO SOBRE CARACTERÍSTICAS FÍSICO-QUÍMICAS E CELULARES DO LÍQUIDO PERITONEAL DE EQUINOS

As one of the most frequently performed surgical techniques and the constant association with complications, ten animals were submitted to castration and physical, chemical and cytological peritoneal fluid characteristics were evaluated. The peritoneal fluid samples were obtained before surgery and after castration. It was evaluated the color and turbidity, total concentration and count of differential leukocyte, lactate, protein and phosphorus, as well as the activity of CK, AST, LDH and FA. After castration, the peritoneal fluid has become reddish and cloudy, there was an increase in protein, lactate and phosphorus as well the activity of CK, AST, AP and LDH. The changes were not associated with the development of postoperative complications and were due to inflammatory response triggered by surgical trauma. The analysis of peritoneal fluid can assist in post castration monitoring to the aiming the early and efficiently resolution of possible complications.

Experience of Patients Treated with Sipuleucel-T in an Academic Setting

ABSTRACT Aim: Sipuleucel–T (ST) is an autologous active cellular immununotherapy for men with metastatic castration-resistant prostate cancer. The role of ST in controlled trial settings has been reported. However, its use in routine clinical care is less well defined. What is the pattern of ST utilization and patient experience in an academic cancer center that was an early provider of ST therapy? Methods: A retrospective registry was generated including all patients with metastatic, castrate resistant prostate cancer treated with ST at the Duke Cancer Institute between 5/2010-10/2012. Data were aggregated from the electronic health record and tumor registry, supplemented by manual abstraction from clinical notes. Data were collected on demographics, treatment patterns, labs, symptoms and clinical endpoints. Findings were compared to those seen in the landmark trial (LT) by Kantoff et al. Results: 94 patients initiated treatment with ST, with 91 completing therapy. Baseline data in the Table compare registry and LT patients. Median PSA prior to therapy was 11.0 ng/mL (n = 82, range: 0.1-1111.2 ng/mL) vs 26.7 ng/mL (n = 77, range: 0.3-3225.6 ng/mL) within 2 months of treatment completion. Median PSA at initiation of therapy in the LT was 51.7 ng/mL. ST was the first agent received post castration resistance in 66% of patients, 2nd line for 15%, 3rd line or greater for 19%. Rigors and chills were documented in 5% and 9% of patients. Median time to next therapy was 89.5 days (range: 9-988). Opiates were used by 16% prior to ST vs 33% within 2 months of completion. The most common symptoms documented within 3 months of ST completion included fatigue (21%), pain (16%), nausea (8%), anorexia (7%), constipation (5%), and anxiety (5%). All grade symptoms in the LT included fatigue (39%), back pain (34%), nausea (28%) and anorexia (7%). Conclusions: Patients treated in the academic setting were largely reflective of those seen in the approval trial, although they appeared healthier at baseline and tolerated therapy relatively well. Endpoints in this patient cohort will mature over time. Disclosure: M.R. Harrison: Grant support: Bristol-Myers Squibb, Argos, Dendreon, Pfizer, Exelixix, Janssen; paid consultant to Exelixis, AVEO, Novartis, Dendreon; speaker honoraria: Novartis, Prometheus, Dendreon; paid to prepare educational presentations: Novartis, Sanofi-Aventis; A.J. Armstrong: Research funding: Medivation, Janssen, Sanofi-Aventis, Dendreon Prostate Cancer Foundation, Department of Defense; Speaker: Dendreon; consultant -Bayer-Algeta, Medivation, Janssen, Sanofi-Aventis, Dendreon; A. Abernethy: Research: NINR, NCI, AHRQ, DARA, Glaxo Smith Kline, Celgene, Helsinn, Dendreon, Kanglaite, Bristol Myers Squibb, Pfizer; consulting - Bristol Myers Squibb, ACORN Research; corporate leadership athenahealth, Orange Leaf Associates; D.J. George: Grant support from Pfizer, Novartis, Genentech/Roche, Glaxo Smith Kline; and is a paid consultant to Pfizer, Novartis, Aveo, Astellas, Bayer, Genentech/Roche; B.R. Hirsch: Grant support from Pfizer, Dendreon, Bristol-Myers Squibb, Glaxo Smith Kline, Agency for Healthcare Research and Quality. All other authors have declared no conflicts of interest.

Different Methods to Identify Pain after Routine Surgical Castration of Equine Stallions: Composite Pain Scale, Facial Expressions, Faecal Glucocorticoid Metabolites and Plasma Cytokines

Reasons for performing studyLack of ‘gold standard’ for pain assessment in horses.ObjectivesTo assess different approaches of quantifying pain in horses. Castration was chosen as a pain model because of its wide clinical relevance.Study designExploratory study.Methods51 equine stallions undergoing castration under general anaesthesia were divided in 3 pain‐relieving treatment groups: A) single perioperative administration of flunixin (n = 19), B) additional subsequent flunixin administrations (n = 21), D) like A but with intra‐operative mepivacaine injections into the spermatic cord (n = 11). All horses were assessed before and 5 times after surgery (up to 44 h) by means of a modified composite pain scale (CPS), a newly developed facial expression pain scale (FEPS), faecal glucocorticoid metabolites (GCMs) and plasma cytokine profiles. The same parameters were measured in a control group C, undergoing general anaesthesia for different nonpainful procedures (n = 6). Data were analysed with nonparametric statistical tests (Wilcoxon, Mann Whitney U).ResultsTime had an influence on CPS and FEPS scores in treatment groups A, B and D but not in C. Scores of groups A and B were higher compared to groups D and C at 4 (CPS, FEPS) and 8 h (CPS), whereas there was no difference between groups A and B nor between groups D and C. Only in group AB was there an increase of faecal GCMs 20 h after surgery. GCMs in group AB were higher compared with groups C and D at 32 h. No effects by time or treatment could be identified for the different plasma cytokines.ConclusionsCPS and FEPS seem to be able to detect different levels of post castration pain differentiating from possible anaesthesia effect. Additional local anaesthesia of the spermatic cord was associated with lower post surgical pain scores when compared to perioperative flunixin application alone, whereas subsequent applications of flunixin had no obvious effect.Ethical animal research: This study was registered as an animal experiment by the Brandenburg state authority (V3‐2347‐A‐42‐1‐2012). Client‐owned horses were included with informed consent. Sources of funding: EU‐funded FP7‐project “Animal Welfare Indicators (AWIN)” (FP7‐KBBE‐2010‐4). Competing interests: None.

Post castration evisceration

See also article by Torre et al.

COMPARATIVE EVALUATION OF THE EPIDURAL DEXMEDETOMIDINE, KETAMINE OR FENTANYL IN COMBINATION WITH BUPIVACAINE IN DOGS

Castration is one of the most common procedure. It is a potential source of mild to moderate pain which is enough to induce inflammatory process, necessitate the incorporation of analgesics. This study was designed to evaluate the effect of epidural bupivacaine alone or in association with fentanyl, ketamine or dexmedetomidine on analgesia for the first 24 h post surgical castration. Forty male mongrel dogs were randomly allocated into 4 groups received bupivacaine 0.25% (1.5 mg kg-1) alone or in combination with fentanyl citrate (2 µg kg-1) or ketamine hydrochloride (2 mg kg-1) or dexmedetomidine hydrochloride (1.13 µg kg-1) into the lumbosacral space. Dogs were scored for sedation using numeric descriptive scale. Analgesia was assessed subjectively through Modified University of Melbourne Pain Scale score and objectively by following up the circulating level of interleukins 6 and 10. The bupivacaine-dexmedetomidine group showed the greatest sedation score, the lowest pain score without neuroendocrine modulation in contrast with bupivacaine or bupivacaine-fentanyl groups. From these result, it is concluded that bupivacaine-dexmedtomidine group provide long term analgesia last for the first 24 h post operative without additional analgesics.

Drip, drip, drip

SummaryA unique complication to castration is published in the preceding Case Report in this issue, whereby a 2‐year‐old Thoroughbred racehorse gelding suffered chronic haemoperitoneum weeks after standing castration. The causes and treatment of post castration haemorrhage are reviewed along with haemoperitoneum and the use of laparoscopy. Supplementary explanations are discussed.

Equine spermatozoa stored in the epididymis for up to 96 h at 4 °C can be successfully cryopreserved and maintain their fertilization capacity

After injury or death of a valuable male, recovery of epididymal spermatozoa may be the last chance to ensure preservation of its genetic material. The objective of this research was to study the effect of sperm storage, at 4°C up to 96h, in the epididymides obtained from castrated horses and its effect on different functional sperm parameters. Aims were to study the effect of (1) sperm storage on viability and chromatin condensation; (2) pre-incubation of recovered epididymal sperm in the freezing extender, prior cryopreservation, on viability and chromatin condensation; and (3) freezing–thawing on viability, chromatin condensation, ROS generation, protein tyrosine phosphorylation and heterologous fertilization rate (ICSI and IVF using bovine oocytes) of sperm recovered from the epididymis up to 96h post castration. The average volume (720±159μL) and the concentration (6.5±0.4×109 spermatozoa/mL) of sperm recovered from the epididymis were not affected by storage. Sperm viability after refrigeration at 4°C for up to72h was similar (P<0.01). The effect of sperm dilution in the freezing media showed similar values up to 48h, while viability was preserved up to 72h (P<0.01). Cryopreserved spermatozoa show similar viability between different storage times. Chromatin condensation was not affected by storage time; however, incubation for 30min in freezing medium and freezing–thawing process induced an increase in the chromatin decondensation. ROS generation was not affected by storage up to 96h. Epididymal storage did not affect sperm protein tyrosine phosphorylation patterns; although the pattern of phosphorylation changed to strong staining of the equatorial segment when the sperm where capacitated in sperm–TALP. Finally, successful and similar pronuclear formation (analyzed by ICSI) and in vitro penetration (evaluated with bovine zone free oocyte) was observed using cryopreserved sperm obtained from prolong epididymal storage at 4°C. In conclusion, cryopreservation of epididymal stallion sperm stored for up to 72h in the epididymis at 4°C, maintain both viability and ability to fertilize in vitro.

Herniation of the small intestine through the femoral canal after castration in a 3‐year‐oldThoroughbred

SummaryComplications following castration are a potential problem in equine practice. Intestinal evisceration is a life‐threatening condition requiring immediate correction. The following case report describes a rare condition associated with post castration evisceration in a 3‐year‐oldThoroughbred. Shortly after the eviscerated small intestine was repositioned in the abdomen, the horse showed signs of colic and at the second surgery a 4.5 m jejunal loop was found incarcerated in the femoral canal. After resection and anastomosis, the femoral canal was obliterated using large moistened gauze sponges. The horse made a complete recovery and returned to race training. The occurrence of femoral hernia, a condition fairly common in man, has been described but no clinical cases have been reported in horses. This is a severe, although rare, complication after castration.

Abstract 5096: Alterations in cholesterol regulation contribute to the production of intratumoral androgens in castration-resistant prostate cancer

Abstract BACKGROUND: Prostate cancer (CaP) is the most commonly diagnosed cancer and third leading cause of cancer-related death in North American males. Recent evidence suggests that androgens mediate disease progression as recurrent CaP tumors contain androgens in levels high enough to activate the androgen receptor (AR). We have previously shown that in the absence of exogenous androgens, CaP cells develop the ability to synthesize their own androgens. We hypothesize that a) androgens induce the in vitro expression and activity of cholesterol synthesis and esterification pathways and b) cholesterol synthesis, influx and efflux are altered in vivo to provide precursors for de novo androgen synthesis contributing to castration-resistant prostate cancer progression. METHODS: We have analyzed cholesterol metabolism in vitro (LNCaP, PC-3 and C4-2 cells in the presence of androgens) and in vivo (LNCaP xenograft model). The LNCaP xenograft model was used to mimic clinical progression of the disease. Tumors were excised from the same mouse at three stages: Androgen-Dependent (AD, prior to castration), Nadir (N, 8-days post castration) and Castration-Resistance (CRPC, 35-days post castration) and stored for further analysis. Protein expressions of AR, PSA and proteins involved in cholesterol synthesis and metabolism, influx and efflux as well as actin were determined by immunoblotting. Total cholesterol concentrations were determined within each excised tumor using a fluorescent assay and LC-MS. Tumoral steroid levels were assessed by LC-MS. RESULTS: Microsomal PC-3 and LNCaP cell HMG CoA reductase (cholesterol biosynthesis) activity was increased upon androgen treatment. ACAT1 activity (cholesterol esterification) was induced by androgens in PC-3 cells and this induction was AR- dependent as well as associated with increased ACAT1 protein expression. Tumor LDLr, SR-BI, HMG CoA reductase, ACAT1 and 2 as well as ABCA1 were altered during disease progression to CRPC likely to increase influx and synthesis of cholesterol. Total cholesterol levels increased in N and CRPC compared to AD. HMG CoA reductase expression was upregulated in N compared to AD (300%) and was maintained at this level at CRPC. Tumoral cholesterol biosynthesis ex vivo was increased from N to CRPC. Testosterone and dihydrosterone increased at CRPC to physiologically relevant levels and this may account for the increase in AR activation as determined by PSA expression at CRPC. CONCLUSIONS: Cellular cholesterol processes are altered by androgens and during progression to CRPC. Cholesterol from increased biosynthesis or uptake is likely a precursor for tumoral de novo androgen synthesis. ACKNOWLEDGEMENTS: Funding for this project was provided by the Canadian Institutes of Health Research (CIHR) and an NCIC-Terry Fox Group grant. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5096.

Evaluation of common vaginal tunic ligation during field castration in draught colts

The objective of this study was to determine if ligation of the common vaginal tunic could prevent or reduce the incidence of omental herniation and eventration in draught colts undergoing routine field castration. It was found that common vaginal tunic ligation, while not completely preventing omental herniation and evisceration, significantly reduced the incidence of these complications and should be considered in those males deemed at increased risk of significant post castration complications.