RESUMO
Measurement of basal adrenocorticotropic hormone (ACTH) concentration is the most commonly used diagnostic test for pituitary pars intermedia dysfunction (PPID). Although several pre-analytical and analytical factors have been reported to affect basal ACTH concentrations in equids, the extent to which these have been evaluated in the context of PPID diagnosis is unclear. The objectives of this scoping review were to identify and systematically chart current evidence about pre-analytical and analytical factors affecting basal ACTH concentrations in adult domestic equids. Systematic searches of electronic databases and conference proceedings were undertaken in June 2022, repeated in October 2022 and updated in August 2023. English language publications published prior to these dates were included. Screening and data extraction were undertaken individually by the authors, using predefined criteria and a modified scoping review data extraction template. After removal of duplicates, 903 publications were identified, of which 235 abstracts were screened for eligibility and 134 publications met inclusion criteria. Time of year, exercise, breed/type and transportation were the factors most frequently associated with significant increases in ACTH concentration (n = 26, 16, 13 and 10 publications, respectively). Only 25 publications reported inclusion of PPID cases in the study population, therefore the relationship between many factors affecting basal ACTH concentration and diagnostic accuracy for PPID remains undefined. However, several factors were identified that could impact interpretation of basal ACTH results. Findings also highlight the need for detailed reporting of pre-analytical and analytical conditions in future research to facilitate translation of evidence to practice.
Assuntos
Doenças dos Cavalos , Doenças da Hipófise , Adeno-Hipófise Parte Intermédia , Cavalos , Animais , Hormônio Adrenocorticotrópico , Adeno-Hipófise Parte Intermédia/metabolismo , Doenças dos Cavalos/diagnóstico , Doenças da Hipófise/diagnóstico , Doenças da Hipófise/veterináriaRESUMO
Pituitary pars intermedia dysfunction (PPID) is an age-related neurodegenerative disorder, affecting >20 % of older horses. There is a need for improved endocrine tests for early disease detection, and the thyrotropin-releasing hormone (TRH) stimulation test has been recommended for diagnosis of early or mild cases. However, it is currently not recommended for year-round use due to marked seasonal variability. The aims of this cohort study were to evaluate effects of month and season on adrenocorticotropic hormone (ACTH) responses to TRH stimulation and to derive monthly cut-offs for PPID diagnosis. Sixty-three horses were assigned to control (n = 17), subclinical PPID (n = 21) and clinical PPID (n = 25) groups, based on a composite reference standard that combined clinical history and examination findings with endocrine test results. TRH stimulation tests were performed monthly for a 12-month period. Circannual changes were evaluated with one- and two-way repeated-measures analysis of variance and receiver operating characteristic curve analysis was used to derive cut-off values for basal and TRH-stimulated ACTH. TRH-stimulated ACTH concentrations were lowest in February-May and highest in August-October. Specificity of both basal and 30 min post-TRH ACTH was generally higher than sensitivity, and TRH stimulation had improved diagnostic accuracy compared to basal ACTH, although its sensitivity was not significantly greater year-round. TRH stimulation tests yielded considerably more positive results than basal ACTH in the subclinical group, but few additional positive results in clinical PPID cases. There were large differences between cut-offs that maximised sensitivity or specificity for TRH-stimulated ACTH, highlighting the importance of considering clinical presentation alongside test results in diagnostic decision-making.
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Doenças dos Cavalos , Doenças da Hipófise , Adeno-Hipófise Parte Intermédia , Cavalos , Animais , Hormônio Adrenocorticotrópico/farmacologia , Hormônio Liberador de Tireotropina/farmacologia , Estações do Ano , Estudos de Coortes , Doenças da Hipófise/diagnóstico , Doenças da Hipófise/veterinária , Adeno-Hipófise Parte Intermédia/metabolismo , Doenças dos Cavalos/diagnósticoRESUMO
Although the equine sarcoid is the most common skin neoplasm in domesticated horses, histopathological characteristics have not previously been evaluated for association with recurrence. The aim of this retrospective cohort study was to investigate clinical and histopathological features of excised equine sarcoids and to evaluate their association with recurrence at the original surgical site and at new sites. Clinical records and excisional biopsies from 106 equine sarcoids from 64 horses referred to Leahurst Equine Hospital, University of Liverpool, between March 2010 and February 2015 were retrieved. Biopsies were re-evaluated histologically. Clinical data were obtained from hospital records, and owner-reported follow-up data were obtained by telephone questionnaire. Associations between clinical and histopathological features of sarcoids and their recurrence at the surgical site were determined using uni- and multivariable mixed effects logistic regression. Recurrence of sarcoids at the surgical site occurred in 30 horses (46.9%). Sarcoids developed at a distant site in 21 horses (32.8%). In the final mixed effects logistic regression model, only superficial inflammation was associated with reduced odds of recurrence at the surgical site (adjusted odds ratio, 0.32; 95% confidence intervals, 0.10-0.96; P = 0.04). This suggests that the inflammatory process may play a role in protecting horses against the recurrence of sarcoids.
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Biosecurity measures are designed to prevent the introduction and spread of pathogens, and play a vital role in the equine industry, controlling endemic diseases and reducing the threat of exotic disease incursion. Equestrian premises differ with respect to disease risks, biosecurity requirements and available facilities. This narrative review summarises reported frequency of implementation for selected biosecurity measures, as well as evidence relating to potential barriers to implementation of biosecurity on equestrian premises. Possible opportunities for improvement in the adoption of equine biosecurity measures are also discussed.
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In horses/ponies with pituitary pars intermedia dysfunction (PPID), pergolide mesylate treatment, with monitoring of therapeutic response, is recommended by contemporaneous literature and equine endocrinologists. However, it is unknown whether these recommendations are adhered to in private practice. This clinical audit aimed to compare treatment and monitoring of PPID cases in veterinary practice against available recommendations. Case data and basal plasma adrenocorticotropic hormone (ACTH) concentrations from all equids tested for PPID between 2012 and 2016 from a single veterinary practice in the UK were obtained. Records were reviewed and information on treatment and monitoring over the subsequent 2-6 years was extracted and compared with published recommendations. After exclusions, the audit population was 480 animals (median age, 20 years). The most common presenting signs were laminitis and/or historical laminitis (51.2%) and hypertrichosis and/or delayed coat shedding (24.5%). Based on seasonally adjusted reference intervals for basal ACTH concentration, 51.7% (n = 248) of animals were classified as positive, 37.1% (n = 178) as negative and 11.3% (n = 54) as equivocal for PPID. Records were available for 459 animals; of which pergolide treatment was initiated in 78.7% (n = 185/235) of positive cases, 19.2% (n = 10/52) of equivocal cases and 6.4% (n = 11/172) of cases classified as negative. Overall, 87.2% (n = 129/148) of cases commenced treatment as per recommendations. Only 77.7% (n = 160/206) of pergolide-treated animals had documented PPID monitoring and of these, only 48.1% (n = 77/160) had follow-up basal ACTH testing in the first 1-3 months following diagnosis. The findings confirm that management of PPID in veterinary practice fell below contemporaneous recommendations, especially for monitoring.
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Measurement of basal adrenocorticotrophic hormone (ACTH) is currently used to diagnose pituitary pars intermedia dysfunction (PPID) in horses, yet a systematic review of the evidence for its use has not been undertaken. This study aimed to systematically review evidence regarding the sensitivity and specificity of the basal ACTH diagnostic test. Electronic databases were systematically searched in January 2019, September 2020 and January 2021, for English language publications published prior to these dates. Screening, data extraction and quality assessment of publications was undertaken by the authors using predefined criteria. Study design, methodology and information reported in included studies were assessed using Standards for Reporting of Diagnostic Accuracy (STARD) checklists. Risk of bias and applicability were appraised using the Quality Assessment tool for Diagnostic Accuracy Studies (QUADAS-2) quality assessment tool. Due to identified biases and marked between-study variations, meta-analysis was not undertaken. After removal of duplicates, 415 publications were identified, of which 25 were evaluated in full, with 11 of these meeting inclusion criteria. In most studies, basal ACTH was reported to have good sensitivity (overall median 75.5%; interquartile range [IQR], 64.0-86.5%; range, 36.0-100%) and excellent specificity (overall median, 95.2%; IQR, 84.2-98.9%; range, 63.3-100%). However, QUADAS-2 and STARD assessment highlighted that studies did not utilise optimal study design and/or study populations for the evaluation of a diagnostic test and the majority were subject to bias, or provided insufficient information to fully assess possible biases. Based on this review, basal ACTH performed better at ruling out PPID than detecting it.
Assuntos
Hormônio Adrenocorticotrópico/sangue , Doenças dos Cavalos/diagnóstico , Doenças da Hipófise/veterinária , Animais , Doenças dos Cavalos/sangue , Cavalos , Doenças da Hipófise/diagnóstico , Adeno-Hipófise Parte Intermédia/metabolismo , Sensibilidade e EspecificidadeRESUMO
Research demonstrating insulin's causal role in endocrinopathic laminitis has greatly advanced understanding of equine laminitis. However, the degree to which this knowledge has been translated into clinical practice has not been assessed. This two-part study aimed to investigate veterinary surgeons' current diagnostic approach to laminitis, whether this had changed over time, and the impact of diagnosing an endocrinopathy on laminitis case management and outcome. Two cross-sectional online surveys of equine veterinary surgeons working within the UK were undertaken. The first study population comprised 141 veterinary surgeons, who had graduated a median of 8 years previously. Overall, 83.6% of respondents (n = 117/140) had changed their diagnostic approach to laminitis since graduating, primarily through increasing use of endocrine testing (88.7%; n = 86/97). Ninety-nine percent (n = 140/141) performed endocrine diagnostic test(s) for some or all laminitis cases at initial and/or subsequent examinations. The second study had 120 participating veterinary surgeons, ≥76% of whom considered diagnosing underlying endocrine diseases greatly influenced their laminitis case management. Where an endocrinopathy was identified, 75.0% (n = 90/120) considered that client communication regarding laminitis was facilitated, and ≥67% considered that treating the endocrinopathy was effective in reducing laminitis recurrence. This study demonstrates successful translation of research knowledge into equine practice, with the vast majority of veterinary surgeons adopting endocrine diagnostic testing within their routine approach to laminitis cases. Respondents perceived that this change in diagnostic approach has resulted in improvements in several non-clinical and clinical healthcare outcomes, including client communication and reduction in recurrent laminitis episodes.
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Doenças do Sistema Endócrino/veterinária , Doenças do Pé/veterinária , Casco e Garras , Inflamação/veterinária , Animais , Estudos Transversais , Doenças do Sistema Endócrino/diagnóstico , Doenças do Pé/diagnóstico , Doenças dos Cavalos/diagnóstico , Cavalos , Inflamação/diagnóstico , Inquéritos e Questionários , Pesquisa Translacional Biomédica , Reino Unido , Médicos Veterinários/tendênciasRESUMO
Pergolide, a dopamine agonist, is commonly administered to manage pituitary pars intermedia dysfunction (PPID), a progressive neurodegenerative disease prevalent in aged horses. However, available evidence regarding pergolide's efficacy in improving clinical and endocrine parameters is limited. The aim of this systematic review was to assess published literature and evaluate evidence regarding whether pergolide treatment results in improvement of clinical signs and/or adrenocorticotrophic hormone (ACTH) concentration compared to no treatment or other unlicensed treatments. Systematic searches of electronic databases were undertaken in April 2019, repeated in August and October 2019, and updated in July 2020. English language publications published prior to these dates were included. Screening, data extraction and quality assessment of publications was undertaken individually by the authors using predefined criteria and subsequently cross-checked. Modified critically appraised topic data collection forms were used to extract data. Due to marked between-study variations, meta-analysis was not undertaken. After removal of duplicate records; 612 publications were identified, of which 129 abstracts were screened for eligibility and 28 publications met criteria for inclusion in the review. Most studies were descriptive case series, cohort studies or non-randomised, uncontrolled field trials. Despite marked variation in study populations, case selection, diagnostic protocols, pergolide dose, follow-up period and outcome measures, in the vast majority of the included studies, pergolide was reported to provide overall clinical improvement in >75% of cases. However, reported improvements in individual clinical signs varied widely. A reduction in plasma ACTH concentrations was reported in 44-74% of cases, while normalisation to within reported reference intervals occurred in 28-74% of cases.
Assuntos
Doenças dos Cavalos/tratamento farmacológico , Pergolida/uso terapêutico , Doenças da Hipófise/veterinária , Adeno-Hipófise Parte Intermédia/efeitos dos fármacos , Hormônio Adrenocorticotrópico/sangue , Animais , Cavalos , Pergolida/administração & dosagem , Doenças da Hipófise/tratamento farmacológico , Resultado do TratamentoRESUMO
The objectives of this study were to establish if exposure of pregnant dairy cows to high environmental temperatures and humidity during the first trimester of pregnancy impairs the establishment of the ovarian reserve (total number of healthy follicles and oocytes in ovaries) and fertility in their offspring. Serum anti-Müllerian hormone (AMH) concentrations and number of follicles ≥3 mm (antral follicle count; AFC) were assessed on a random day of the estrous cycle in 310 sixteen-month-old dairy heifers. Based on season of their conception and early fetal life, heifers were separated into 2 groups: summer (mean monthly temperature-humidity index = 69.33 ± 2.6) and winter (temperature-humidity index = 54.91 ± 1.08). The AMH and AFC were lower in summer (419.27 ± 22.81 pg/mL and 9.32 ± 0.42 follicles, respectively) compared with winter heifers (634.91 ± 47.60 pg/mL and 11.84 ± 0.46 follicles, respectively) and were not influenced by farm and age at sampling. Heifers born to dams that were not being milked during gestation had lower AMH and AFC compared with offspring of cows on their first lactation, whereas no difference was detected between offspring of cows on their first and subsequent lactations. Summer and winter heifers had similar age at first service and at first calving, and similar number of services per conception. Regardless of season in early fetal life, heifers were classified into 3 groups based on AMH and AFC (low = 20%, intermediate = 60%, high = 20%). Heifers with the lowest AMH were older at first service compared with herd mates with intermediate AMH, but age at first calving and number of services per conception were similar among AMH categories. No difference was detected in any of the fertility measures among AFC categories. Heifers born to mothers exposed to high environmental temperatures in early gestation had smaller ovarian reserves compared with herd mates conceived in winter, but no association between season of early fetal life and fertility at first conception was established. Season of conception and maternal lactation status affect the size of the ovarian reserve, but not fertility, at first conception in the progeny.
Assuntos
Hormônio Antimülleriano/sangue , Bovinos/fisiologia , Fertilidade , Reserva Ovariana , Animais , Meio Ambiente , Ciclo Estral , Feminino , Fertilização , Temperatura Alta , Umidade , Lactação , Oócitos/fisiologia , Ovário/fisiologia , Gravidez , Estações do AnoAssuntos
Obstrução da Saída Gástrica/diagnóstico por imagem , Obstrução da Saída Gástrica/etiologia , Pancreatite/complicações , Pancreatite/diagnóstico por imagem , Endoscopia do Sistema Digestório , Feminino , Derivação Gástrica , Obstrução da Saída Gástrica/cirurgia , Humanos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios XRESUMO
Fasting horses for measurement of basal serum insulin concentration (fasting insulin; FI) has been recommended to standardise testing for insulin dysregulation (ID), yet limited data exist comparing it to dynamic tests. This study aimed to compare FI with the combined glucose-insulin test (CGIT) in horses suspect for ID. We hypothesised that FI would have poor sensitivity for detecting ID compared to CGIT using conventional cut-offs. Records were retrieved from CGITs performed in horses fasted for approximately 8h. Serum insulin and glucose concentrations were measured before and for 150min following an IV bolus of glucose followed by insulin. Correlations between FI and CGIT values were assessed. Youden's index analysis was used to determine the optimal cut-off for FI. Logistic regression and Mann-Whitney U tests were used to determine factors affecting the results. CGITs (n=130) from 62 horses were evaluated. Compared to CGIT, sensitivity and specificity of FI for diagnosis of ID were 14.6% and 100% at a cut-off of 20µIU/mL and 63.4% and 87.2% at a cut-off of 5.2µIU/mL, respectively. FI was significantly correlated with insulin at 45min (rs=0.66) and 75min (rs=0.72); area under the curve for insulin (AUCinsulin; rs=0.67); glucose at 45min (rs=0.53); and AUCglucose (rs=0.50). Obesity was significantly associated with increased odds of a positive CGIT and horses with a positive CGIT were significantly older (P<0.05). In conclusion, FI correlated well with CGIT results and had adequate sensitivity and specificity at lower cut-offs, despite poor sensitivity at conventional cut-off values. Further research to derive cut-off values relevant to the fasting period is warranted.
Assuntos
Glicemia/metabolismo , Teste de Tolerância a Glucose/veterinária , Doenças dos Cavalos/diagnóstico , Insulina/sangue , Animais , Jejum , Feminino , Doenças dos Cavalos/sangue , Cavalos , Masculino , Linhagem , Sensibilidade e EspecificidadeRESUMO
Published information on the pharmacokinetic and pharmacodynamic properties of pergolide is limited. The aim of this study was to investigate the pharmacokinetic and pharmacodynamic properties of oral pergolide in horses with pituitary pars intermedia dysfunction (PPID). The study design was a nonrandomized clinical trial. Six horses with PPID diagnosed by thyrotropin-releasing hormone (TRH) stimulation tests received pergolide at 4 µg/kg for 18 d. Plasma samples for determination of pergolide and ACTH concentration were collected 0.5 h before and 2 and 12 h after each administration of pergolide. Maximum plasma concentrations after the first oral dose of pergolide (0.104-0.684 ng/mL; median 0.261 ng/mL; interquartile range [IQR] 0.184-0.416 ng/mL) were not significantly different to the maximum steady-state concentration at day 18 (0.197-0.628 ng/mL; median 0.274; IQR 0.232-0.458 ng/mL). Chronic administration was not associated with drug accumulation (R = 1.09) and pergolide concentration reached steady state within 3 d. Throughout, concentrations of pergolide fluctuated considerably, with median plasma peak concentrations more than four times higher than median trough concentrations. Plasma ACTH concentration reduced significantly within 12 h of administration with further reductions occurring up to 10 d after the initiation of treatment. Although there were parallel fluctuations in the concentrations of pergolide and ACTH, timing of ACTH measurement in relation to the administration of pergolide did not have a significant effect. Alterations in the response to TRH were identified at 8 d with no further change being identified at 18 d. A small number of horses were studied. Oral pergolide results in significant suppression of pars intermedia activity within hours. Pergolide and ACTH concentrations fluctuated in tandem although correlation was poor. Fluctuations in pergolide concentration were consistent with a terminal elimination half-life of less than 12 h. To reduce the level of fluctuation of ACTH, twice-daily dosing of pergolide may be more appropriate.
Assuntos
Doenças dos Cavalos/tratamento farmacológico , Pergolida/farmacocinética , Doenças da Hipófise/veterinária , Adeno-Hipófise Parte Intermédia/efeitos dos fármacos , Administração Oral , Hormônio Adrenocorticotrópico/sangue , Animais , Área Sob a Curva , Cavalos , Pergolida/administração & dosagem , Pergolida/sangue , Pergolida/uso terapêutico , Doenças da Hipófise/tratamento farmacológico , Hormônio Liberador de Tireotropina/administração & dosagem , Hormônio Liberador de Tireotropina/farmacologiaRESUMO
Three preliminary and linked studies investigate the impact of making alterations to factors considered relevant to engaging in and experiencing intra-group aggression (bullying) among adult male patients detained in a single secure forensic hospital. Study one (n = 44) outlines the institutional factors, attitudes towards bullying and environmental factors that increase the likelihood of engaging in bullying and/or being victimised. Study two (n = 53 patients and 167 staff) assesses the effect of three variations of intervention that aimed to reduce intra-group aggression through direct alteration of the physical and psychosocial environment, using data from both patients and staff. Study three (n = 414) looks at the effects of two variations of the intervention used in study two, which offered patients' participation in individual and communal activities. It was predicted that changes to the physical and social environment would produce a reduction in the factors shown to predict intra-group aggression. Attitudes supportive of bullying and the presence of social hierarchies each increased the likelihood of engaging in bullying. Indirect changes to the social environment on the wards had more positive effects than those incorporating direct alterations to the physical and social environment. The differences in effectiveness of the two approaches are discussed in relation to the established predictors of intra-group aggression. The research concludes by noting the preliminary nature of the research and outlining potential directions for future research and intervention.
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BACKGROUND: Previous studies suggest that ocular disease is common among aged horses but owners may fail to identify or underestimate their clinical relevance. OBJECTIVES: To document the prevalence of owner-reported ocular disease in horses aged ≥15 years. In a subset of these horses, to document ophthalmic findings from veterinary examination and compare with owner-reported ocular disease, and to determine risk factors for veterinary ophthalmic findings. STUDY DESIGN: Cross-sectional study. METHODS: Owners of aged horses completed a survey on management, clinical signs and medical history. Risk factors for the presence of ocular disease as reported by the owner were determined. A subset of these horses underwent an ophthalmological examination. Risk factors for the presence of ocular disease detected during this examination were determined. Agreement between owner-reported data and veterinary ophthalmic findings was assessed. RESULTS: Abnormal ocular findings were detected in 287/327 horses aged ≥15 years that underwent a complete ophthalmic examination, whereas the presence of ocular disease as reported by the horse-owners was only 3.3%. Agreement between owner-reported ocular disease and results of the veterinary examination was low for all categories analysed. An owner-reported history of ocular discharge was associated with increased odds of veterinary-reported diminished vision. Increasing age was associated with increased odds of the presence of an eye abnormality (any) and cataracts. Appaloosa horses had increased odds of cataract compared with other breeds. Horses in work were less likely to have an eye abnormality. MAIN LIMITATIONS: Volunteer bias may have influenced our results with owners of sick horses or those more concerned about their horses more likely to volunteer at the initial recruitment phase. CONCLUSIONS: This study showed a high prevalence of ocular lesions in aged horses which was not reflected in owner-reported disease. This has highlighted problems in obtaining information on ocular conditions from horse-owners.
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Oftalmopatias/veterinária , Doenças dos Cavalos/diagnóstico , Envelhecimento , Animais , Oftalmopatias/diagnóstico , Oftalmopatias/patologia , Cavalos , Fatores de RiscoRESUMO
Anti-Müllerian hormone (AMH) is an ovarian growth factor that plays an important role in regulation of ovarian follicle growth. The objectives of this study were to estimate the genomic heritability of AMH and identify genomic regions associated with AMH production in a genome-wide association (GWA) analysis. Concentrations of AMH were determined in 2,905 dairy Holstein heifers genotyped using the Zoetis medium density panel (Zoetis Inclusions, Kalamazoo, MI) with 54,519 single nucleotide polymorphism (SNP) markers remaining after standard genotype quality control edits. A linear mixed model was used to model the random effects of sampling day and genomics on the logarithm of AMH. The genomic heritability (± standard error of the mean) of AMH was estimated to be 0.36 ± 0.03. Our GWA analysis inferred significant associations between AMH and 11 SNP markers on chromosome 11 and 1 SNP marker on chromosome 20. Annotated genes with significant associations were identified using the Ensembl genome database (version 88) of the cow genome (version UMD 3.1; https://www.ensembl.org/biomart). Gene set enrichment analysis revealed that 2 gene ontology (GO) terms were significantly enriched in the list of candidate genes: G-protein coupled receptor signaling pathway (GO:0007186) and the detection of chemical stimulus involved in sensory perception (GO:0050907). The estimated high heritability and previously established associations between AMH and ovarian follicular reserve, fertility, longevity, and superovulatory response in cattle implies that AMH could be used as a biomarker for genetic improvement of reproductive potential.
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Hormônio Antimülleriano/análise , Bovinos/genética , Estudo de Associação Genômica Ampla/veterinária , Animais , Feminino , Fertilidade , Genômica , Folículo Ovariano , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Development of a bovine model without ovarian follicular waves (waveless) and transient increases in gonadotropin secretion during estrous cycles may lead to new methods to more consistently regulate ovulatory follicle growth thereby improving efficiency of embryo transfer. We hypothesized that the GnRH antagonist acyline would inhibit gonadotropin secretion thereby blocking follicular waves, ovarian function and ovulation during estrous cycles of cattle. To test this hypothesis, beef heifers (nâ¯=â¯5 per group) were treated twice daily with vehicle (control) or 25 or 50⯵g/kg acyline beginning 12â¯h after GnRH-induced ovulation and ending 21 days later. Each animal was subjected to ovarian ultrasonography for 25 days to monitor number and growth of follicles ≥3â¯mm in diameter and growth of the corpus luteum (CL). Blood samples were taken at various intervals to determine circulating concentrations of FSH, LH, anti-Müllerian hormone (AMH, marker of small follicle growth) and progesterone. Results show that acyline treatment decreased or blocked: circulating concentrations of LH, transient FSH spikes associated with emergence of follicular waves, preovulatory FSH/LH surges, follicular waves, dominant follicle development, CL growth, and progesterone production. In contrast, the largest acyline dose increased AMH concentrations. In conclusion, long-term acyline treatment blocks follicular waves but not growth of preantral and small antral follicles (≤ 3â¯mm). Future studies will determine if the waveless bovine model, which has enhanced development of preantral and small antral follicles, can be used to develop new methods to improve predictability of response of cattle to superovulation.
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Bovinos/fisiologia , Antagonistas de Hormônios/farmacologia , Oligopeptídeos/farmacologia , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Animais , Hormônio Antimülleriano/metabolismo , Relação Dose-Resposta a Droga , Feminino , Antagonistas de Hormônios/administração & dosagem , Oligopeptídeos/administração & dosagem , ProgesteronaRESUMO
Pituitary pars intermedia dysfunction (PPID) is caused by an age-related degenerative disease of dopaminergic neurones. Despite its importance in equine practice, available information regarding its epidemiology is limited. This systematic review aimed to assess published literature to evaluate available evidence regarding the clinical presentation, prevalence and risk factors for PPID in horses and ponies. Electronic database searches were undertaken using a range of terms, and English language publications published prior to August 2016 were included. Both authors independently reviewed screened papers for inclusion, extracted data, and assessed the quality of reporting using predefined criteria. Data were extracted using modified critically appraised topic data collection forms. Meta-analysis was not undertaken due to marked between-study variations. Following removal of duplicate records, of 358 published papers yielded by the search, 97 abstracts were screened for eligibility and 29 publications meeting inclusion criteria were included in the review. Most studies reviewed were case series or cross-sectional studies, with considerable variation in study populations and PPID case definition. Hypertrichosis and/or other hair coat abnormalities, laminitis and epaxial muscle wastage or muscle atrophy are the most frequently reported clinical signs, with prevalence of these signs increasing with increasing horse age. The most robust prevalence estimates for PPID were 21.2% in horses and ponies aged ≥15 years and 2.9% amongst the general equine population. Findings regarding breed and sex predispositions were equivocal and only increasing age has been identified as a significant risk factor for PPID.
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Doenças dos Cavalos/epidemiologia , Doenças da Hipófise/veterinária , Adeno-Hipófise Parte Intermédia , Envelhecimento , Animais , Feminino , Cavalos , Masculino , Doenças Neurodegenerativas/complicações , Doenças Neurodegenerativas/veterinária , Doenças da Hipófise/epidemiologia , Doenças da Hipófise/etiologia , Fatores de RiscoRESUMO
Ciliates have been reported as pathogens of many species of economically important bivalves. Mussel protozoan X (MPX), is an uncharacterised intracellular ciliate of mussels and has been widely reported in Mytilus spp. around the world. In order to characterise this ciliate, Mytilus edulis samples were collected from a site on the West coast of Scotland, and four different fixatives for histological examination were tested. Fresh preparations of mussel digestive glands were also examined by laser scanning confocal microscopy. Intracellular ciliates were prepared by laser capture microdissection and partial sequences of small subunit ribosomal RNA gene and of large subunit ribosomal RNA gene were generated, using Phyllopharyngea primers. Methacarn solution proved to be the best fixative for both histological and molecular characterisation. The morphological and molecular investigations confirmed that this ciliate belongs to the class Phyllopharyngea, order Rhynchodida. However, this organism does not belong to any known family, genus or species, therefore, a new description is necessary, following further morphological analyses. Most mussel samples containing MPX displayed mild to moderate infections, with no signs of necrosis or haemocytic response, although a single sample displayed a severe infection (â¼103 ciliates per section). The localisation of this ciliate in tissues other than the digestive gland, the presence of necrosis in infected tissue of the most severely infected mussel and the binary fission of this ciliate have been observed here for the first time. We also report the first observation of the live ciliate isolated from tissue. Although MPX remains of unknown significance to the mussel industry, tools and protocols described here will be useful in further characterising these and other ciliates (subclass Rhynchodia) known as pathogens for bivalves.
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Cilióforos , Mytilus edulis/parasitologia , Animais , Cilióforos/genética , Genes de Protozoários , FilogeniaRESUMO
BACKGROUND: Horses are reported to return to a variety of disciplines following unilateral enucleation; however, owners of horses with ocular disease are frequently reluctant to consider the procedure. There is little published information investigating owners' attitudes towards, and satisfaction following, enucleation. OBJECTIVES: To investigate the hypotheses: 1) horses return to their previous level of work following unilateral enucleation and 2) their owners are satisfied with the post-operative outcome. STUDY DESIGN: Retrospective case series with cross-sectional survey. METHODS: Clinical records from eight equine referral centres in the United Kingdom were reviewed to identify horses that underwent enucleation between August 2006 and March 2015. Owner questionnaires were completed to corroborate information provided by medical records and obtain information on client perceptions. RESULTS: A total of 170 cases were identified and 119 owner questionnaires completed. The most frequent primary uses of horses in the study were pleasure/leisure riding, showjumping and dressage, with 25.2% (n = 30) of horses used for competition. Following enucleation, 77.3% (n = 92) of horses were performing at an equivalent or higher level than prior to enucleation and 60.0% (n = 18/30) of competition horses were competing at an equivalent or higher level. Complications related to the surgical site (predominantly mild post-operative swelling) were reported in 3.7% of cases and nonocular complications in 3.7% of cases. Of owners who reported being concerned or very concerned about certain factors prior to surgery, ≥86.8% reported that these factors caused little or no issue post-surgery. Most owners, 90.8% (n = 108) were pleased with the outcome following surgery, with 21.3% (n = 23/108) wishing the procedure had been undertaken sooner. MAIN LIMITATIONS: Retrospective data collection from clinical records and the potential for recall bias. CONCLUSIONS: Horses can return successfully to a variety of disciplines following enucleation. Owners are satisfied with the outcome and pleased that enucleation was performed.
Assuntos
Enucleação Ocular/veterinária , Doenças dos Cavalos/cirurgia , Propriedade , Animais , Estudos Transversais , Coleta de Dados , Feminino , Cavalos , Humanos , Masculino , Estudos Retrospectivos , Inquéritos e Questionários , Resultado do Tratamento , Reino UnidoRESUMO
OBJECTIVES: To evaluate the effect of syringe size, needle size, number of needle passes and operator experience on cell yield from tumour fine-needle aspirates, and the quantity and quality of extractable RNA. MATERIALS AND METHODS: Fine-needle aspirates were collected from canine lymphoma, cutaneous mast cell tumour, anal gland adenocarcinoma, fibrosarcoma and oral malignant melanoma using nine different techniques. RESULTS: There was a significant difference in cell yield between fine-needle aspirate techniques for melanoma, lymphoma and anal gland adenocarcinoma. The application of suction yielded the largest number of cells. Cell numbers in lymphoma and fibrosarcoma aspirates collected by different veterinary surgeons were not significantly different. Use of a smaller gauge needle and suction increased the quantity of RNA isolated from fibrosarcoma and anal gland adenocarcinoma aspirates, but did not influence RNA integrity. CLINICAL SIGNIFICANCE: Suction during fine-needle aspiration increases cell numbers obtained from five common canine tumours. Suction increases the quantity of RNA isolated from anal gland adenocarcinoma and fibrosarcoma aspirates without affecting RNA quality. Junior veterinary surgeons gain comparable cell numbers to senior staff.