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1.
J Vet Intern Med ; 37(3): 1015-1020, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37084042

RESUMO

BACKGROUND: The ability to detect bacteriuria in dogs with a point-of-care test might improve medical care and antimicrobial stewardship. HYPOTHESIS AND OBJECTIVE: A rapid immunoassay (RIA; RapidBac) will provide acceptable sensitivity and specificity for diagnosis of bacteriuria. ANIMALS: Forty-four client-owned dogs with a clinical indication for urinalysis and aerobic bacterial urine culture. METHODS: Prospective study. Urine, collected by cystocentesis, was submitted for urinalysis and culture at a diagnostic laboratory. Owners completed an enrollment questionnaire regarding their dogs' clinical signs. The RIA was performed according to the manufacturer's guidelines. Results were compared to culture. RESULTS: Forty-four urine specimens were evaluated from 44 dogs. The sensitivity and specificity of the RIA test to detect bacteriuria compared to urine culture were 81.8% (95% CI, 65.7%-97.9%) and 95.5% (95% CI, 86.8%-99.9%), respectively. For cultures yielding ≥103  CFU/mL, sensitivity increased to 90.0% (95% CI, 76.9%-100%) and specificity was similar at 95.2% (95% CI, 86.1%-99.9%). Malodorous urine, bacteriuria, and pyuria were more likely to be present in dogs with positive RIA or urine culture results compared to dogs with negative results. CONCLUSIONS AND CLINICAL IMPORTANCE: The RIA was easy to perform and had good sensitivity and excellent specificity in this group of dogs. The RIA might be a useful screening test for decision-making regarding antimicrobial therapy in dogs with a clinical indication for urine culture. Consideration could be given to amending the International Society for Companion Animal Infectious Disease definition of bacterial cystitis as the presence of signs of lower urinary tract disease together with positive culture or a positive RIA.


Assuntos
Infecções Bacterianas , Bacteriúria , Doenças do Cão , Infecções Urinárias , Cães , Animais , Bacteriúria/diagnóstico , Bacteriúria/veterinária , Bacteriúria/microbiologia , Estudos Prospectivos , Urinálise/veterinária , Infecções Bacterianas/veterinária , Radioimunoensaio/veterinária , Infecções Urinárias/veterinária , Doenças do Cão/diagnóstico , Doenças do Cão/tratamento farmacológico , Doenças do Cão/microbiologia
2.
J Vet Diagn Invest ; 34(1): 90-93, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34470514

RESUMO

Determination of serum or plasma progesterone (P4) concentrations is important to recognize pregnant and non-pregnant ewes, and also to predict the number of carried lambs. The 2 most common methodologies for the detection of plasma P4 are radioimmunoassay (RIA) and enzyme immunoassay (EIA). RIA is very expensive, and not all laboratories are equipped to perform this test; EIA is commercially available for human use, but only a few companies produce species-specific kits, which are expensive. We verified for ovine plasma a less expensive and easily available ELISA kit (DiaMetra) designed to quantify P4 in humans. Pools of ovine and human plasma were used to compare repeatability, accuracy, sensitivity, and stability of P4 measured by the DiaMetra kit. Repeatability data were within 15%, and accuracy values were ~90% for both plasma matrices. Stability data showed a loss of <20% for freeze-thaw and <30% for 30-d storage. All parameters were acceptable under international guidelines for method validation. The human ELISA kit was used successfully to quantify plasma P4 in 26 ewes during pregnancy until delivery. P4 concentrations were also correlated with the number of carried lambs.


Assuntos
Progesterona , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Humanos , Técnicas Imunoenzimáticas , Gravidez , Radioimunoensaio/veterinária , Ovinos
3.
Theriogenology ; 147: 116-123, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31806245

RESUMO

Serum progesterone (sP4) measurement is commonly used to determine the optimal time for mating in bitches, and to diagnose reproduction-related abnormalities. Radioimmunoassay (RIA) is the gold standard assay, but is becoming less available, and has several practical disadvantages. Chemiluminescence immunoassays (CLIA) are commonly used in human medicine for sP4 measurement, and are becoming more available in veterinary medicine. Our objective was to compare the sP4 results obtained by RIA and two CLIA systems (Immulite-Siemens [IS-CLIA] and Elecsys-Roche [ER-CLIA]) in the same sera in 60 client-owned healthy bitches at different estrous cycle stages. The agreement between the two CLIAs and RIA was examined using the Passing-Bablok regression and Bland Altman plots. Comparing sP4 concentrations measured by the IS-CLIA to the RIA yielded an intercept of 0.16 ng/mL (95% confidence interval [95%CI], 0.03-0.25) with a slope of 0.45 (95%CI, 0.44-0.47) and a median difference of -2.10 ng/mL (P < 0.0001) that was strongly correlated to the average of measurements (r = -0.97; P < 0.0001). Comparing sP4 concentrations measured by the ER-CLIA to the RIA yielded an intercept of -0.23 ng/mL (95%CI, -0.56 to -0.09) with a slope of 1.06 (95%CI, 1.00-1.12) and a median difference of -0.09 ng/mL (P = 0.9), that was weakly correlated to the average of measurements (r = 0.34; P = 0.018). The performance of the ER-CLIA was similar to the RIA, while the IS-CLIA showed significantly different results compared to the RIA. Our study supports the conclusion that sP4 results generated by the ER-CLIA can be used interchangeably with RIA results for clinical purposes, while IS-CLIA results require adjustment to RIA results for clinical practice.


Assuntos
Cães/sangue , Medições Luminescentes/veterinária , Progesterona/sangue , Radioimunoensaio/veterinária , Animais , Feminino , Medições Luminescentes/métodos , Radioimunoensaio/métodos , Reprodutibilidade dos Testes
4.
Pol J Vet Sci ; 22(4): 695-701, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31867920

RESUMO

Progesterone (P4) is responsible for the main reproduction processes. Concentration of P4 varies widely among different determination methods, and interpretation of these values may be difficult. The objective of the current study was to assess the agreement of three different enzyme immunoassays (ELISA) in relation to radioimmunoassay (RIA) of P4 concentration assessment of beef cow serum samples. Samples were collected randomly considering high (pregnant cows) and low (non-pregnant cows) P4 concentrations. Depending on the P4 assessment method, four groups were created as follows: Group 1 - direct samples assessed by ELISA, Group 2 - extracted samples assessed by ELISA, Group 3 - samples assessed by automated ELISA, and Group 4 - samples assessed by RIA. The mean progesterone concentration was 4.50 ng/mL, 1.24 ng/mL, 4.07 ng/mL and 4.39 ng/mL from Group 1 to Group 4, respectively. The mean difference (MD) between Group 1, Group 2 and Group 3 individually compared with Group 4 was -0.10 ± 1.24 ng/mL, 3.15 ± 3.58 ng/mL and 0.33 ± 1.42 ng/mL, and the 95% confidence interval (CI) for the differences (s) was from -0.99 to 0.78 ng/mL, from 0.59 to 5.71 ng/mL, and from -0.69 to 1.34 ng/mL, respectively. The confidence interval for the lower and upper limit of the agreement ranged from -4.12 to -1.05 ng/mL and from 0.84 to 3.91 ng/mL between Group 1 and Group 4, from -8.45 to 0.42 ng/ mL and from 5.88 to 14.75 ng/mL between Group 2 and Group 4, from -4.29 to -0.76 ng/mL, and from 1.41 to 4.94 ng/mL between Group 3 and Group 4. Our findings show that the best agreement with RIA was observed for Group 1 and Group 3, while the agreement in the extraction method was least accurate.


Assuntos
Análise Química do Sangue/veterinária , Bovinos/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Progesterona/sangue , Radioimunoensaio/veterinária , Animais , Análise Química do Sangue/métodos , Feminino
5.
J S Afr Vet Assoc ; 90(0): e1-e6, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31714111

RESUMO

The Coat-A-Count® radioimmunoassay has been long and widely used to determine the concentration of progesterone in serum or plasma of bitches (progRIA), but was discontinued in 2014. The Immulite® 1000 LKPG1 chemiluminescence immunoassay has gained prominence since 2003 to determine the concentration of progesterone in serum of bitches, but the assay changed in 2012 (Immulite® 1000 LKPW1). This study assessed the feasibility of using Immulite® 1000 LKPW1 (progImm) to estimate the time of clinically relevant events during oestrus and compared progRIA and progImm 2 and 3 days after the first or only day of the luteinizing hormone surge (LH1). ProgImm first exceeded 5.1 nmol/L on the same day that progRIA first exceeded 6 nmol/L, a proxy for the occurrence of the LH surge, or the day before in 28 of 31 (90%) of oestrous periods. ProgImm first exceeded 13.6 nmol/L on the same day that progRIA first exceeded 16 nmol/L (a proxy for the day of ovulation) or the day before in 34 of 35 (97%) oestrous periods. ProgImm first exceeded 5.4 nmol/L on LH1 or the day before in 24 of 25 (95%) of oestrous periods. The median of progImm 2 days after LH1 was 1.2 nmol/L lower than the 10.7 nmol/L of progRIA (p = 0.001). The mean of progImm 3 days after LH1 was 2.2 nmol/L lower than the 19.0 nmol/L of progRIA (p 0.001). In conclusion, the days on which progImm first exceeded 5.1 nmol/L, 13.6 nmol/L and 5.4 nmol/L effectively estimate the days on which progRIA reached 6 nmol/L or 16 nmol/L or LH1.


Assuntos
Cães/sangue , Medições Luminescentes/veterinária , Detecção da Ovulação/veterinária , Progesterona/sangue , Radioimunoensaio/veterinária , Animais , Tomada de Decisão Clínica , Estro/sangue , Feminino , Medições Luminescentes/métodos , Detecção da Ovulação/métodos , Radioimunoensaio/métodos , Reprodução/fisiologia
6.
Vet Immunol Immunopathol ; 215: 109904, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31420068

RESUMO

During immune activation, CD25 is expressed by T cells, and its soluble form (sCD25) is released into the extracellular matrix and the bloodstream. In humans, serum sCD25 concentrations are used as a surrogate marker for autoimmune diseases, malignancies, and transplant rejection. However, a canine-specific assay for the measurement of sCD25 in dog serum has not previously been described. Therefore, the aims of this study were to develop and analytically validate a radioimmunoassay to measure sCD25 in canine serum, to establish a reference interval for canine sCD25, and to test the clinical utility of this assay with serum samples for dogs with various diseases. A competitive radioimmunoassay (RIA) was developed and analytically validated. Analytical validation consisted of lower limit of detection (LLOD), dilutional parallelism, spiking recovery, and intra- and inter-assay variability using pooled surplus canine serum samples. A reference interval was established in healthy dogs and serum samples from dogs with various types of neoplasia, IBD, liver disease, suspected pancreatitis, or suspected small intestinal disease and serum samples with an increased C-reactive protein concentration (CRP) were analyzed to test the clinical utility of the assay. LLOD was calculated to be 0.5 ng/mL. The mean (±SD) observed-to-expected ratio (O/E) for serial dilutions was 101.7 ±â€¯14.0%, and the mean (± SD) O/E for spiking recovery was 93.2 ±â€¯4.2%. Coefficients of variation (CVs) for intra-assay variability were ≤12.5% (mean ±â€¯SD: 7.5 ±â€¯4.2%), and inter-assay CVs were ≤15.7% (mean ±â€¯SD: 11 ±â€¯4.4%). A reference interval (RI) for canine sCD25 of 1.2-4.2 ng/mL was established from a population of 112 clinically healthy dogs. Dogs with neoplasia and dogs with suspected small intestinal disease had decreased concentrations of serum sCD25 when compared to healthy dogs (p < 0.0001, respectively). However, the majority of clinical samples used in this study were within the reference interval. Median concentrations of serum sCD25 were 1.9 ng/mL for healthy dogs. Dogs with cancer, IBD, liver disease, suspected pancreatitis, or suspected small intestinal disease, as well as sera with an increased serum CRP concentration, had median serum sCD25 concentrations of 1.6 ng/mL, 2.1 ng/mL, 2.2 ng/mL, 1.7 ng/mL, 1.5 ng/mL, and 1.8 ng/mL, respectively. Thus, the RIA described here is linear, accurate, precise, and reproducible for measuring sCD25 in canine serum. However, this assay shows little clinical utility of sCD25 as a biomarker for dogs with inflammatory, autoimmune, and/or neoplastic conditions.


Assuntos
Doenças do Cão/sangue , Cães/sangue , Subunidade alfa de Receptor de Interleucina-2/sangue , Radioimunoensaio/veterinária , Animais , Doenças do Cão/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Humanos , Radioimunoensaio/métodos , Valores de Referência , Sensibilidade e Especificidade
7.
J Zoo Wildl Med ; 49(3): 638-647, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30212354

RESUMO

Reproductive management of cownose rays ( Rhinoptera bonasus) under professional care plays an important role in conservation of the species, but hormone and ultrasonographic analyses of their 12-mo reproductive cycle have not been documented previously. Plasma reproductive hormone concentrations (17B-estradiol, progesterone, testosterone, and androstenedione) were measured monthly via radioimmunoassay for 1 yr in an aquarium-managed population of adult females ( n = 15) and males ( n = 5). Ultrasounds of the uterus were performed each month at the time of sample collection to identify gestation stage (0-5) based on a previously developed in-house staging system. Stages were correlated to hormone concentrations to track progression through pregnancy. Thirteen females were reproductively active, and each produced one pup in March-June, similar to timing for free-ranging populations. Female estradiol increased steadily throughout gestation from stages 0 to 5, while progesterone, testosterone, and androstenedione were increased only in early gestation (stages 1 and 2). Unlike month of year, gestation stage strongly predicted hormone concentration, but specific values to predict parturition date were not identified. Male testosterone and progesterone were higher in March-June (mating season) than July-January, while estradiol and androstenedione did not exhibit a seasonal pattern. Aquarium-managed cownose rays have similar reproductive patterns to what is reported in wild populations. Ultrasonographic monitoring with serial hormone analysis and accurate mating records will provide the most useful information for managing a reproductive population of cownose rays in an aquarium setting.


Assuntos
Estradiol/sangue , Progesterona/sangue , Rajidae/sangue , Testosterona/sangue , Ultrassonografia/veterinária , Viviparidade não Mamífera/fisiologia , Animais , Embrião não Mamífero , Desenvolvimento Embrionário , Estradiol/fisiologia , Feminino , Masculino , Progesterona/fisiologia , Radioimunoensaio/veterinária , Reprodução/fisiologia , Rajidae/fisiologia , Testosterona/fisiologia
8.
J Vet Diagn Invest ; 30(4): 517-522, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29717637

RESUMO

Measurement of serum trypsin-like immunoreactivity (TLI) is used to assess exocrine pancreatic function in dogs and cats. Ferrets ( Mustela putorius furo) serve as valuable animal models for human diseases such as cystic fibrosis and other pulmonary diseases, and may be a useful model of other diseases including pancreatitis. We developed and analytically validated a competitive radioimmunoassay (RIA) for measurement of TLI in ferret serum by determination of analytical sensitivity, assay linearity, accuracy of spiking recovery, precision, and reproducibility. Analytical sensitivity of the assay was 0.55 µg/L. Observed-to-expected (O/E) ratio for dilutional parallelism was 90.2-127.9% (mean: 108.1 ± 11.9%). The O/E ratio for spiking recovery was 94.5-113.0% (mean: 103.9 ± 7.2%). The intra- and inter-assay coefficients of variation (CVs) were 2.7-5.7% and 3.5-8.2%, respectively. The reference interval (RI) for serum TLI derived from 31 healthy ferrets was 28-115 µg/L; the 90% confidence interval for the lower and upper limits of the RI were 10.0-32.1 µg/L and 103-126 µg/L, respectively. This TLI RIA is analytically sensitive, sufficiently linear, accurate, precise, and reproducible for the measurement of TLI in ferret serum samples.


Assuntos
Furões/sangue , Pâncreas/metabolismo , Radioimunoensaio/veterinária , Tripsina/sangue , Animais , Modelos Animais de Doenças , Insuficiência Pancreática Exócrina/sangue , Insuficiência Pancreática Exócrina/veterinária , Coelhos , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade da Espécie
9.
Anim Reprod Sci ; 192: 179-184, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29545003

RESUMO

Blood progesterone concentration is used in several procedures related to the reproduction in the bitch, such as ovulation monitoring, estimating time of parturition, or hypo-luteoidism management. Several techniques are available to evaluate blood progesterone concentration, such as the radioimmunoassay (RIA), the chemiluminescent immunoassay (CLIA), and the enzyme-linked immunosorbent assay (ELISA). The aim of this study was to compare the blood progesterone concentration using these three methods during the periovulatory period of 23 bitches. Vaginal cytology was used to classify cytologic estrus (CE) and cytologic diestrus (CD), and blood samples were collected once during proestrus and every other day between CE and CD. The samples were retrospectively classified in the different phases of the estrus based on CD. Pregnancy rate and gestational length were also recorded. A significant increase of the circulating progesterone during the progression of the estrus was recorded, and there were significant differences in the values when using the different methods, with lesser, intermediate, and greatest values with use of the RIA, CLIA, and ELISA, respectively. There was a high correlation (Pearson's correlation coefficient = 0.978) and substantial strength-of-agreement (Lin's concordance correlation coefficient = 0.966) between values obtained when using CLIA and RIA, while there was a high correlation (Pearson's correlation coefficient = 0.955) but poor strength-of-agreement (Lin's concordance correlation coefficient = 0.866) with use of the ELISA and RIA. The data reported in this study provide evidence that the method used for measuring the blood progesterone concentration during the periovulatory phase of the bitch significantly affected the progesterone values.


Assuntos
Cães/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Medições Luminescentes/veterinária , Ovulação/fisiologia , Progesterona/sangue , Radioimunoensaio/veterinária , Animais , Cães/fisiologia , Ciclo Estral/fisiologia , Feminino , Ovulação/sangue , Gravidez
10.
BMC Vet Res ; 13(1): 112, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28431528

RESUMO

BACKGROUND: Onset of canine transitional cell carcinoma (TCC) and prostatic carcinoma (PCA) is usually insidious with dogs presenting at an advanced stage of the disease. A biomarker that can facilitate early detection of TCC/PCA and improve patient survival would be useful. S100A8/A9 (calgranulin A/B or calprotectin) and S100A12 (calgranulin C) are expressed by cells of the innate immune system and are associated with several inflammatory disorders. S100A8/A9 is also expressed by epithelial cells after malignant transformation and is involved in the regulation of cell proliferation and metastasis. S100A8/A9 is up-regulated in human PCA and TCC, whereas the results for S100A12 have been ambiguous. Also, the urine S100A8/A9-to-S100A12 ratio (uCalR) may have potential as a marker for canine TCC/PCA. Aim of the study was to evaluate the diagnostic accuracy of the urinary S100/calgranulins to detect TCC/PCA in dogs by using data and urine samples from 164 dogs with TCC/PCA, non-neoplastic urinary tract disease, other neoplasms, or urinary tract infections, and 75 healthy controls (nested case-control study). Urine S100A8/A9 and S100A12 (measured by species-specific radioimmunoassays and normalized against urine specific gravity [S100A8/A9USG; S100A12USG], urine creatinine concentration, and urine protein concentration and the uCalR were compared among the groups of dogs. RESULTS: S100A8/A9USG had the highest sensitivity (96%) and specificity (66%) to detect TCC/PCA, with specificity reaching 75% after excluding dogs with a urinary tract infection. The uCalR best distinguished dogs with TCC/PCA from dogs with a urinary tract infection (sensitivity: 91%, specificity: 60%). Using a S100A8/A9USG ≥ 109.9 to screen dogs ≥6 years of age for TCC/PCA yielded a negative predictive value of 100%. CONCLUSIONS: S100A8/A9USG and uCalR may have utility for diagnosing TCC/PCA in dogs, and S100A8/A9USG may be a good screening test for canine TCC/PCA.


Assuntos
Doenças do Cão/diagnóstico , Complexo Antígeno L1 Leucocitário/urina , Neoplasias Urogenitais/veterinária , Neoplasias Urológicas/veterinária , Animais , Biomarcadores/urina , Calgranulina A/análise , Calgranulina B/urina , Carcinoma de Células de Transição/diagnóstico , Carcinoma de Células de Transição/urina , Carcinoma de Células de Transição/veterinária , Estudos de Casos e Controles , Creatinina/urina , Doenças do Cão/urina , Cães , Feminino , Masculino , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/urina , Neoplasias da Próstata/veterinária , Proteinúria/urina , Proteinúria/veterinária , Radioimunoensaio/veterinária , Neoplasias Urogenitais/diagnóstico , Neoplasias Urogenitais/urina , Doenças Urológicas/diagnóstico , Doenças Urológicas/urina , Doenças Urológicas/veterinária , Neoplasias Urológicas/diagnóstico , Neoplasias Urológicas/urina
11.
Vet Clin Pathol ; 45(1): 148-53, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26840919

RESUMO

BACKGROUND: Hyperthyroidism is common in older cats, which necessitates frequent screening of serum total thyroxine (TT4) concentrations. Fast, cheap, and reliable methods to measure TT4 in cats are needed. OBJECTIVES: The purpose of the study was the validation of a human TT4 enzyme immunoassay (EIA) for use with feline serum, and derivation of a TT4 reference interval (RI) for cats aged 9 years and older. METHODS: Assay precision, reproducibility, and linearity were evaluated. Interference by hemolysis was also assessed. Method comparison studies between the human EIA and a previously validated radioimmunoassay (RIA) and chemiluminescent-enzyme immunoassay (CEIA) were performed. Healthy cats (> 9 years) were recruited from 3 UK first opinion practices. RESULTS: The human TT4 EIA demonstrated good precision and reproducibility, and adequate linearity. Hemolysis did not significantly alter measured TT4 concentrations until HGB > 8 g/L. Method comparison revealed proportional and constant errors between EIA and RIA/CEIA. The TT4 RI for cats (> 9 years) was calculated as 7.1-45.1 nmol/L (n = 49). CONCLUSIONS: The human TT4 EIA was successfully validated for use with feline serum and offers a rapid, cheap, and reliable method for determination of serum TT4 concentrations in cats.


Assuntos
Doenças do Gato/diagnóstico , Hipertireoidismo/veterinária , Técnicas Imunoenzimáticas/veterinária , Tiroxina/sangue , Animais , Gatos , Feminino , Hipertireoidismo/diagnóstico , Masculino , Radioimunoensaio/veterinária , Valores de Referência , Reprodutibilidade dos Testes , Testes de Função Tireóidea/veterinária
12.
Endocrinology ; 157(1): 70-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26496022

RESUMO

In primates, despite the fact that GnRH neurons are mature at birth, a gonadal steroid independent central inhibition restrains the initiation of puberty. The neural substrates responsible for this central inhibition, however, are unclear. In this study, we tested the hypothesis that neuroestradiol release in the hypothalamus decreases prior to the pubertal increase in GnRH release. We found that in female monkeys at the prepubertal stage, when GnRH release was low, estradiol (E2) levels in the stalk-median eminence of the hypothalamus were higher than those in older, early pubertal females in which nocturnal GnRH release begins to increase. Furthermore, estrone (E1) levels were higher in the stalk-median eminence of prepubertal and early pubertal monkeys compared with midpubertal monkeys, which have the highest GnRH release. The elevated E2 and E1 levels at the prepubertal stage are likely hypothalamic in origin because circulating E2 and E1 levels in prepubertal and early pubertal monkeys were much lower than those in midpubertal monkeys. Heightened synthesis and release of neuroestradiol during the prepubertal period and subsequent reduction at puberty onset indicate possible roles for neuroestradiol in central inhibition of GnRH release. The mechanism governing the reduction in neuroestradiol synthesis at puberty onset remains to be determined.


Assuntos
Regulação para Baixo , Estradiol/metabolismo , Macaca mulatta/fisiologia , Eminência Mediana/metabolismo , Neurônios/metabolismo , Ovulação , Maturidade Sexual , Animais , Cromatografia Líquida de Alta Pressão/veterinária , Estradiol/sangue , Estrona/sangue , Estrona/metabolismo , Feminino , Hormônio Liberador de Gonadotropina/sangue , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Macaca mulatta/sangue , Eminência Mediana/crescimento & desenvolvimento , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Hipófise/crescimento & desenvolvimento , Hipófise/metabolismo , Radioimunoensaio/veterinária , Espectrometria de Massas em Tandem/veterinária , Wisconsin
13.
Reprod Biol ; 14(3): 234-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25152522

RESUMO

The purpose of this study was to investigate whether fertile or non-fertile inseminations (AI) in synchronized ewes are correlated with the electrical resistance of cervical mucus (ERCM) and the ovarian steroid concentration. AIs were performed either at fixed-time (group A) or after estrus detection (group B). Retrospective analysis revealed that at AI, pregnant ewes had lower ERCM values and progesterone concentrations than non-pregnant ones (p<0.05). It appears that ERCM may be used as an additional index for fertility enhancement of inseminated ewes.


Assuntos
Muco do Colo Uterino/química , Regulação para Baixo , Inseminação Artificial/veterinária , Ovário/metabolismo , Progesterona/sangue , Carneiro Doméstico/fisiologia , Animais , Animais Endogâmicos , Impedância Elétrica , Estradiol/análise , Estradiol/sangue , Estradiol/metabolismo , Detecção do Estro , Sincronização do Estro , Feminino , Grécia , Modelos Lineares , Gravidez , Progesterona/metabolismo , Radioimunoensaio/veterinária , Fatores de Tempo
14.
J Vet Intern Med ; 28(5): 1433-41, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25040917

RESUMO

BACKGROUND: Determination of the urinary corticoid-to-creatinine ratio (UCCR) is an important screening test in the diagnosis of hypercortisolism (HC). However, urinary cortisol metabolites interfere with cortisol measurement in immunoassays, leading to decreased specificity. Gas chromatography-mass spectrometry (GC-MS) is considered the gold standard for steroid hormone analysis, because it provides a high level of selectivity and accuracy. OBJECTIVES: To prospectively compare the UCCR of healthy dogs and dogs with HC determined by 5 different immunoassays and by GC-MS and to evaluate the influence of veterinary care on UCCR. ANIMALS: Twenty healthy dogs; 18 dogs with HC. METHODS: Urine was collected in the hospital and again after 6 days at home. Three chemiluminescence immunoassays (Access 2, Beckmann; Immulite 2000, DPC Siemens, with and without trichloromethane extraction) and 2 RIAs (Utrecht in house; Access Beckmann) were used. GC-MS analyses were performed with Agilent 6890N/5973N. Urinary corticoid concentrations were related to urinary creatinine concentrations. RESULTS: Immunoassay results were significantly higher compared to GC-MS results. Evaluation of bias plots and clinical assessment made on the basis of the assay results of each dog indicated substantial disagreement among the assays. Sensitivity varied from 37.5 to 75% and with selected assays was lower in samples from day 6 compared to day 0. GC-MS was not superior to the immunoassays in discriminating healthy from HC dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: Considerable variation must be anticipated comparing different urinary cortisol assays. Establishing an assay- and laboratory-specific reference range is critical when using UCCR.


Assuntos
Corticosteroides/urina , Síndrome de Cushing/veterinária , Doenças do Cão/urina , Cães/urina , Cromatografia Gasosa-Espectrometria de Massas/veterinária , Imunoensaio/veterinária , Animais , Creatinina/urina , Síndrome de Cushing/urina , Feminino , Medições Luminescentes/veterinária , Masculino , Estudos Prospectivos , Radioimunoensaio/veterinária
15.
Primates ; 55(4): 459-65, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24939341

RESUMO

The measurement of hormones in fecal samples allows for the noninvasive assessment of the endocrine status of free-ranging primates. However, procedures and techniques for hormone analysis in feces must be validated, both analytically and physiologically. Few studies have addressed the endocrinology of black howler monkeys (Alouatta pigra). Due to its conservation status, direct handling of individuals from this species and invasive sample collection are highly regulated, and therefore traditional methods for the validation of hormone assays, such as pharmacological challenges, are not allowed. As a consequence, sometimes studies of the fecal hormones of free-ranging black howler monkeys do not report physiological validations and therefore the biological reliability of such measurements cannot be assessed. In order to stimulate future research with this species, the present study aimed at providing methodological bases for fecal endocrine monitoring. Specifically, we compared the validity of two immunoassays (radioimmunoassays, RIA; solid-phase chemiluminescent enzyme immunoassay, SPCEI) performed with commercial kits to measure cortisol, testosterone, estradiol, and progesterone; and demonstrate how the physiological functions of these steroid hormones can be determined through non-pharmacological validations. We found no differences between the analytical validity of RIA and SPCEI assays to measure cortisol and testosterone, whereas for estradiol and progesterone RIA showed better results. Concerning the physiological validation of our assays, we demonstrated that: (1) comparisons between pre- and post-stress situations may be used to assess cortisol response, (2) comparisons between females and males may be used to assess variation in testosterone levels, and (3) comparisons between pregnant and non-pregnant females may be used to determine variation in estradiol and progesterone activity. The analytical and physiological validations that we performed demonstrate that there are currently commercial kits that allow for correct endocrine monitoring of this species, and that there are non-pharmacological alternatives to assess the biological validity of hormone measurements.


Assuntos
Alouatta/fisiologia , Fezes/química , Hormônios/química , Medições Luminescentes/veterinária , Radioimunoensaio/veterinária , Animais , Feminino , Hormônios/fisiologia , Medições Luminescentes/métodos , Masculino , Gravidez , Radioimunoensaio/métodos , Reprodutibilidade dos Testes , Especificidade da Espécie
16.
J Feline Med Surg ; 16(5): 395-406, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24794036

RESUMO

PRACTICAL RELEVANCE: Pancreatitis is a frequent finding in cats, the chronic form being more common than the acute form. Despite the large number of diseases or conditions that may be associated with feline pancreatitis, in most cases no cause is diagnosed and the pancreatitis is said to be idiopathic. The chronic form can be mild and asymptomatic, and has a high prevalence in apparently healthy cats. This has generated debate concerning the clinical significance of chronic feline pancreatitis. However, several reports have demonstrated the severity of clinical signs in certain forms of acute feline pancreatitis, while other studies have reported a strong association between chronic pancreatitis and the development of comorbidities such as hepatic lipidosis, diabetes mellitus, inflammatory bowel disease or exocrine pancreatic insufficiency. This suggests that feline pancreatitis should not be overlooked. CLINICAL CHALLENGES: Diagnosis of feline pancreatitis is complicated by the non-specific clinical signs and poor diagnostic value of basic biochemistry and haematology or imaging techniques. Development of a feline-specific pancreatic lipase immunoassay has improved our diagnostic ability in the past decade, but may have more limited application for mild and chronic forms of pancreatitis. Moreover, histopathology (the 'gold standard' diagnostic test) can be associated with false-negative results due to multifocal distribution of lesions or mild forms of the disease. With respect to treatment, it is important to take into account the idiosyncrasies of the feline species when considering medical therapies. EVIDENCE BASE: This article reviews the literature on feline pancreatitis, focusing on the different forms and their relative clinical significance, while explaining difficulties inherent in the diagnosis of this disease. An overview of current recommendations for the management of cats with pancreatitis is also provided.


Assuntos
Doenças do Gato/diagnóstico , Doenças do Gato/terapia , Pancreatite/veterinária , Doença Aguda , Animais , Gatos , Doença Crônica , Medicina Baseada em Evidências , Lipase/sangue , Pâncreas/diagnóstico por imagem , Pâncreas/enzimologia , Pancreatite/diagnóstico , Pancreatite/terapia , Radioimunoensaio/veterinária , Tomografia Computadorizada por Raios X/veterinária , Ultrassonografia , Medicina Veterinária
17.
Poult Sci ; 92(10): 2745-53, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24046423

RESUMO

Lines of evidence suggested that systems involved in the regulation of the stress responses and energy homeostasis are highly integrated. Because cerulenin, the natural antibiotic product of the fungus Cephalosporium ceruleans and a broad-spectrum fatty acid synthesis (FAS) inhibitor, has been shown to affect food intake and energy balance, and because the biomarker of stress Hsp-70 gene was found to interact directly with fatty acids, we hypothesized that cerulenin may regulate Hsp-70 gene expression. Therefore, the present study was undertaken to examine this issue. Cerulenin administration significantly (P < 0.05) decreased food intake and induced Hsp-70 mRNA levels in muscle, but not in liver or hypothalamus of 2-wk-old broiler chickens. These changes were accompanied by an unpregulation of muscle uncoupling protein and carnitine palmitoyltransferase 1 mRNA levels. This result indicated that the regulation of Hsp-70 gene expression in normal chickens, as estimated by oxidative stress indices [TBA reacting substances, ferric reducing/antioxidant power, and ceruloplasmin oxidase activity] levels, is tissue-specific. In attempt to discriminate between the effect of cerulenin and cerulenin-reduced food intake on Hsp-70 gene expression, we also evaluated the effect of food deprivation on the same cellular responses. Food deprivation for 16 h did not affect Hsp-70 gene expression in all tissues examined, indicating that the effect of cerulenin is independent of the inhibition of food intake. To ascertain whether the effect of cerulenin is direct or indirect, we carried out in vitro studies. Cerulenin treatment did not affect Hsp-70 gene expression in Leghorn male hepatoma and quail myoblast cell lines, suggesting that the observed effect in vivo may be mediated through the central nervous system.


Assuntos
Cerulenina/farmacologia , Galinhas/genética , Inibidores da Síntese de Ácidos Graxos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/genética , Animais , Southern Blotting/veterinária , Cerulenina/administração & dosagem , Ceruloplasmina/metabolismo , Galinhas/metabolismo , Inibidores da Síntese de Ácidos Graxos/administração & dosagem , Compostos Férricos/sangue , Proteínas de Choque Térmico HSP70/metabolismo , Especificidade de Órgãos , Oxirredução , Radioimunoensaio/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
18.
Trop Anim Health Prod ; 45(7): 1461-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23990459

RESUMO

The Girolando breed is used in pasture-based dairy production systems in Brazil to associate the high production of Bos taurus to the rusticity and thermal adaptation of Bos indicus. This study was designed to evaluate the physiological response to a gonadotropin-releasing hormone (GnRH)-prostaglandin F2α (PGF2α)-GnRH protocol to synchronize the ovulation in 40 Girolando heifers of a pasture-based dairy production system and its relationships with the temperature and humidity index (THI) during the dry (DS) and rainy season (RS) in the tropical savannah-Brazil's cerrado biome. Responses were characterized by follicular and corpus luteum number and diameter, ovulation (D9), and pregnancy rates after first AI. Total follicle number (8.1 ± 0.3 × 8.8 ± 0.3), D9 ovulatory follicle diameter (11.9 ± 0.4 × 10.1 ± 0.4 mm), corpus luteum diameter (8.6 ± 1.3 × 3.9 ± 1.5 mm), corpus luteum score (3.7 ± 0.8 × 1.8 ± 1.0), corpus luteum diameter after AI (9.6 ± 1.6 × 3.9 ± 1.5 mm), and corpus luteum score after AI (3.2 ± 0.4 × 0.9 ± 0.6) in DS and RS differed (P < 0.01). D9 ovulation rate was 40 % (DS) and 20 % (RS), without differences (P > 0.05). Pregnancy rate was 45 % (DS) and 11 % (RS), with differences (P < 0.01). THI differed between DS and RS (P < 0.01). THI may interfere in the follicular and luteal dynamics and in the response of Girolando heifers to the GnRH-PGF2α protocol in the tropical savannah, thus reducing the chances of pregnancy at the first artificial insemination.


Assuntos
Bovinos/fisiologia , Corpo Lúteo/fisiologia , Dinoprosta/farmacologia , Sincronização do Estro/métodos , Hormônio Liberador de Gonadotropina/farmacologia , Folículo Ovariano/fisiologia , Ovulação/efeitos dos fármacos , Criação de Animais Domésticos , Animais , Brasil , Bovinos/genética , Corpo Lúteo/diagnóstico por imagem , Feminino , Umidade , Folículo Ovariano/diagnóstico por imagem , Gravidez , Taxa de Gravidez , Progesterona/sangue , Radioimunoensaio/veterinária , Estações do Ano , Temperatura , Clima Tropical , Ultrassonografia/veterinária
19.
Br Poult Sci ; 54(2): 252-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23647190

RESUMO

1. The effect of daidzein, a naturally occurring phytoestrogen, on the reproductive performance of 120 female Zhedong White geese was determined. The geese were divided into 4 groups which were fed on diets containing 0 (Control), 10 (Da1), 20 (Da2) and 30 (Da3) mg daidzein per kg diet. Egg production and weight, fertility and hatchability rates, concentrations of estradiol (E2), triiodothyronine (T3), progesterone (P4), thyroxine (T4) and growth hormone (GH) in serum, and mRNA levels of gonadotropin releasing hormone (GnRH), ß-follicle stimulating hormone (FSHß), follicle stimulating hormone receptor (FSHR), oestrogen receptor1 (ESR1), oestrogen receptor2 (ESR2), prolactin (PRL), prolactin receptor (PRLR), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in the hypothalamus-pituitary-gonadal axis (HPGA) were measured. 2. Daidzein increased egg weight and fertility but had no detectable effect on egg production and hatchability. 3. Daidzein affected serum P4 and GH concentrations and T4 rhythm, up-regulated GnRH mRNA and PRLR mRNA levels in the hypothalamus, down-regulated PRLR mRNA in the hypothalamus, PRL mRNA in the pituitary, and ESR2 mRNA levels in the ovary, respectively. The mRNA rhythms of PRLR in the hypothalamus, PRL, PRLR and FSHß in the pituitary, FSHR, ESR1 and ESR2 in the ovary were significantly changed in the Da2 group. 4. It is suggested that an appropriate dose of daidzein might improve reproductive performance by affecting serum hormone concentrations and rhythms and regulating gene mRNA levels in the HPGA of female Zhedong White geese.


Assuntos
Gansos/fisiologia , Regulação da Expressão Gênica , Hormônios/sangue , Isoflavonas/metabolismo , Fitoestrógenos/metabolismo , Reprodução , Ração Animal/análise , Criação de Animais Domésticos , Animais , Dieta/veterinária , Relação Dose-Resposta a Droga , Feminino , Gansos/genética , Sistema Hipotálamo-Hipofisário/metabolismo , Ovário/metabolismo , RNA Mensageiro/análise , Radioimunoensaio/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Estações do Ano
20.
Animal ; 7(8): 1367-73, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23597263

RESUMO

Abrupt weaning, a usual management in sheep productive systems, may provoke behavioural and physiological responses indicative of stress in ewes and lambs. Progesterone (P4) has anxiolytic and sedative effects through the union of its metabolites that contain 3α-hydroxyl group to the γ-aminobutyricacidA receptor. Our first aim was to determine whether P4 administration reduces the behavioural and physiological responses of ewes to abrupt weaning of lambs. A complementary aim was to determine whether P4 treatment affects the milk yield and composition of ewes, and the BW of their lambs. In experiment 1, seven ewes received P4 treatment for 32 days (group E1-P4), and eight ewes remained as an untreated control group (group E1-C). BW of the lambs was recorded during P4 treatment. Lambs were weaned at 59 days (Day 0 = weaning). The main behaviours of the ewes before and after weaning were recorded using 10 min scan sampling. The ewes' serum total protein, albumin and globulin concentrations were measured before and after weaning of the lambs. In experiment 2, milk yield and composition were determined in two different groups of six ewes treated with P4 (group E2-P4) for 16 days and in five untreated controls (group E2-C). The BW of lambs increased with time (P = 0.001) in both groups and did not differ. The percentage of observations in which the ewes were seen pacing on Day 0 was greater in the E1-C group than in the E1-P4 group (P = 0.0007). Similarly, the percentage of observations in which the ewes were recorded vocalizing on Day 0 was greater in the E1-C group than in the E1-P4 group (P = 0.04). The percentage of observations in which E1-C ewes were recorded lying did not change from Days 0 to 1; however, it increased in E1-P4 ewes. Total serum protein concentration did not change in E1-P4 ewes from Days 0 to 3, although a decrease was seen in E1-C ewes (P = 0.04). Serum globulin concentration was greater in E1-P4 ewes on Day 3 than in E1-C ewes (P = 0.0008). In experiment 2, there were no differences between E2-P4 and E2-C ewes in terms of milk yield, protein, fat and lactose content. Progesterone administration reduced the behavioural and physiological responses of ewes to abrupt weaning of lambs, and this effect was not mediated by changes in milk yield and composition, or by lambs' BW.


Assuntos
Leite/química , Leite/metabolismo , Progesterona/administração & dosagem , Carneiro Doméstico/fisiologia , Desmame , Animais , Peso Corporal , Feminino , Lactação , Progesterona/sangue , Radioimunoensaio/veterinária , Carneiro Doméstico/crescimento & desenvolvimento , Estresse Fisiológico
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