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Pathophysiology of small testes in beef bulls: relationship between scrotal circumference, histopathologic features of testes and epididymides, seminal characteristics, and endocrine profiles.
1986
Rao Veeramachaneni D.N. | Ott R.S. | Heath E.H. | McEntee K. | Bolt D.J. | Hixon J.E.
Effect of long-term administration of ketoconazole in cats.
1986
Willard M.D. | Nachreiner R.F. | Howard V.C. | Fooshee S.K.
Effect of trenbolone and testosterone on the plasma elimination rates of sulfamethazine, trimethoprim, and antipyrine in female dwarf goats.
1988
Miert A.S.J.P.A.M. van | Peters R.H.M. | Basudde C.D.K. | Nijmeijer S.N. | Duin C.T.M. van | Gogh H. van | Korstanje C.
Plasma elimination rates of sulfamethazine (100 mg/kg of body weight, IV), trimethoprim (20 mg/kg, IV), and antipyrine (35 mg/kg, IV) were studied in adult female dwarf goats (n = 5) before and after implantation with trenbolone acetate (5 mg/kg). Pretreatment with trenbolone caused a significant decrease in the elimination rate of the drugs tested: for sulfamethazine, 5 times; for antipyrine, 3 times; and for trimethoprim, 2 times. After treatment with testosterone (1 mg/kg, SC, twice weekly for 2.5 weeks), female goats (n = 5) had a similar decrease in the elimination rate of sulfamethazine. Other induced effects included a change in social behavior, a lower voice, and the development of a typical billy goat-like odor. Plasma creatinine concentrations after androgen administration were significantly higher than those before androgen administration; changes were not observed in plasma urea values. Because of the differences observed, we believe that more attention should be paid to the effects of androgenic agents on drug kinetic properties, with particular reference to studies on clinical efficacy, side effects, and drug residues in food products.
Afficher plus [+] Moins [-]Development of an enzyme immunoassay for determination of steroid hormones to improve the reproductive efficiency of domestic animals.
1993
Choi H.S. | Kang B.K.
Effect of the infection with the nematode Haemonchus contortus (Strongylida: Trichostrongylidae) on the haematological, biochemical, clinical and reproductive traits in rams Texte intégral
2016
Rouatbi, Mariem | Gharbi, Mohamed | Rijeibi, Mohammed | Ben Salem, Imene | Akkari, Hafidh | Lassoued, Narjess | Rekik, Mourad
This study aimed to investigate the effect of Haemonchus contortus infection on rams’ haematological, biochemical and clinical parameters and reproductive performances. A total number of 12 Barbarine rams (control and infected) were included in the experiment. The infected group received 30 000 H. contortus third-stage larvae orally. Each ram’s ejaculate was immediately evaluated for volume, sperm cell concentration and mortality rate. At the end of the experiment (day 82 post-infection), which lasted 89 days, serial blood samples were collected in order to assess plasma testosterone and luteinising hormone (LH) concentrations. There was an effect of time, infection and their interaction on haematological parameters (p < 0.001). In infected rams, haematocrit, red blood cell count and haemoglobin started to decrease from 21 days post-infection. There was an effect of time and infection for albumin. For total protein, only infection had a statistically significant effect. For glucose, only time had a statistically significant effect. Concentrations were significantly lower in infected rams compared to control animals. A significant effect of infection and time on sperm concentrations and sperm mortality was observed. The effect of infection appears in time for sperm concentrations at days 69 and 76 post-infection. Sperm mortality rate was significantly higher in infected animals at day 46 post-infection when compared to control group (p < 0.05). Finally, plasma testosterone traits (average concentration, cumulated levels during the sampling period and pulse frequency) were depressed in infected rams when compared to control counterparts; none of these endocrine traits were affected for plasma LH.
Afficher plus [+] Moins [-]Effects of α-enolase gene silencing on reproductive-related hormone receptor expression and steroid hormone synthesis of primary granulosa cells from goose F1 follicles Texte intégral
2020
Ji, Hong | Niu, Chun-Yang | Zhang, Hong-Liang | Guo, Jing-Ru | Zhen, Li | Lian, Shuai | Yang, Chuang | Yang, Huan-Min | Wang, Jian-Fa
Effects of α-enolase gene silencing on reproductive-related hormone receptor expression and steroid hormone synthesis of primary granulosa cells from goose F1 follicles Texte intégral
2020
Ji, Hong | Niu, Chun-Yang | Zhang, Hong-Liang | Guo, Jing-Ru | Zhen, Li | Lian, Shuai | Yang, Chuang | Yang, Huan-Min | Wang, Jian-Fa
Enolases are enzymes in the glycolytic pathway, which catalyse the reversible conversion of D-2-phosphoglycerate into phosphoenol pyruvate in the second half of the pathway. In this research, the effects of α-enolase (ENO1) on steroid reproductive-related hormone receptor expression and on hormone synthesis of primary granulosa cells from goose F1 follicles were studied. Primary granulosa cells from the F1 follicles of eight healthy 8-month-old Zi geese were separated and cultured. An ENO1 interference expression vector was designed, constructed and transfected into primary cultured granulosa cells. The mRNA expression levels of follicle-stimulating hormone receptor (FSHR), luteinising hormone receptor (LHR), oestrogen receptor α (ER α), oestrogen receptor β (ER β), growth hormone receptor (GHR) and insulin-like growth factor binding protein-1 (IGFBP-1) in the cells were evaluated as were the secretion levels of oestradiol, activin, progesterone, testosterone, inhibin and follistatin in cell supernatant. α-enolase gene silencing reduced the expression of FSHR, LHR, ERα, ERβ, GHR, and IGFBP-1 mRNA, potentiated the secretion of oestrogen, progesterone, testosterone, and follistatin of granulosa cells, and hampered the production of activin and inhibin. ENO1 can regulate the reactivity of granulosa cells to reproductive hormones and regulate cell growth and development by adjusting their hormone secretion and reproductive hormone receptor expression. The study provided a better understanding of the functional action of ENO1 in the processes of goose ovary development and egg laying.
Afficher plus [+] Moins [-]Effects of α-enolase gene silencing on reproductive-related hormone receptor expression and steroid hormone synthesis of primary granulosa cells from goose F1 follicles Texte intégral
2020
Ji Hong | Niu Chun-Yang | Zhang Hong-Liang | Guo Jing-Ru | Zhen Li | Lian Shuai | Yang Chuang | Yang Huan-Min | Wang Jian-Fa
Enolases are enzymes in the glycolytic pathway, which catalyse the reversible conversion of D-2-phosphoglycerate into phosphoenol pyruvate in the second half of the pathway. In this research, the effects of α-enolase (ENO1) on steroid reproductive-related hormone receptor expression and on hormone synthesis of primary granulosa cells from goose F1 follicles were studied.
Afficher plus [+] Moins [-]Toxicological evaluation of flumequine in pubertal male rats after oral administration for six weeks Texte intégral
2018
Kang, JeongWoo | Hossain, Md Akil | Choi, Byungkook | Cho, Joon-Hyoung | Kang, Seok-Jin | Ku, Hyun-Ok | Jeong, Sang-Hee | Kang, Hwan-Goo
Toxicological evaluation of flumequine in pubertal male rats after oral administration for six weeks Texte intégral
2018
Kang, JeongWoo | Hossain, Md Akil | Choi, Byungkook | Cho, Joon-Hyoung | Kang, Seok-Jin | Ku, Hyun-Ok | Jeong, Sang-Hee | Kang, Hwan-Goo
Veterinarians use flumequine (FLU) widely but its toxicological effects are still unclear. FLU doses of 53, 200, or 750 mg/kg were administered orally for six weeks to pubertal male rats for evaluation of their toxicity. Weight gain was poorer after seven days of exposure to FLU 750, but relative weights of the brain, adrenal and thyroid glands, and testes were notably higher. Haematological and lipid profile parameters, cardiac markers, and inorganic phosphate significantly increased in the FLU 750 group. Blood glucose, oestradiol and serum concentrations of immunoglobulins G (IgG) and E (IgE) significantly decreased after treatment. The levels of interleukins 10 (IL-10) and 6 (IL-6) fell significantly in the FLU 200 and FLU 750 groups. Cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) and cyclooxygenase-2 (Cox-2) expression amplified after treatment. Serum levels of free triiodothyronine (fT3) and free thyroxine (fT4) reduced in the FLU 200 and FLU 750 groups without changes in total T3 or T4 level. All doses of FLU significantly depressed concentrations of thyroid-stimulating hormone (TSH) and testosterone. Histopathology of thyroid glands from rats treated with FLU 750 showed degeneration and depletion of thyroid follicular epithelial cells. Expression of 8-hydroxydeoxyguanosine (8-OHdG) was increased in a dose-dependent manner in the brain, but decreased in the testes. Expression of CYP1A1 increased in the adrenal and pituitary glands. The results of this study suggest that the toxicity of FLU in rats is an effect of its disruptive influence on the pituitary-thyroid hormonal system and on the dysfunction of the immune system.
Afficher plus [+] Moins [-]Toxicological evaluation of flumequine in pubertal male rats after oral administration for six weeks Texte intégral
2018
Kang JeongWoo | Hossain Md Akil | Choi Byungkook | Cho Joon-Hyoung | Kang Seok-Jin | Ku Hyun-Ok | Jeong Sang-Hee | Kang Hwan-Goo
Veterinarians use flumequine (FLU) widely but its toxicological effects are still unclear.
Afficher plus [+] Moins [-]Development of LC-MS/MS confirmatory method for the determination of testosterone in bovine serum Texte intégral
2017
Woźniak-Sobczak, Barbara | Matraszek-Żuchowska, Iwona | Witek, Sebastian | Posyniak, Andrzej
Development of LC-MS/MS confirmatory method for the determination of testosterone in bovine serum Texte intégral
2017
Woźniak-Sobczak, Barbara | Matraszek-Żuchowska, Iwona | Witek, Sebastian | Posyniak, Andrzej
Introduction: In the European Union the use of steroid growth promoters is prohibited under Council Directive 96/22/EC. For effective control of illegal use of natural steroids, highly sensitive analytical methods are required, because sex hormones can be present in very low concentrations in biological samples. The aim of the study was to develop a confirmatory method for the detection of testosterone in bovine serum at ppt level. Material and Methods: 17β-testosterone and internal standards of 17β-testosterone-d2 were extracted from serum samples with a mixture of tert-butyl methyl ether/petroleum ether and were directly analysed by an LC/MS/MS on QTRAP 5500 instrument with a TurboIon-Spray source operating in a positive ionisation mode. Chromatographic separation was achieved on the analytical column Inertsil® ODS-3 with an isocratic elution using mobile phase consisting of acetonitrile, methanol, and water. Method validation has been carried out in accordance with the Commission Decision 2002/657/EC. Results: The method was characterised by good recovery (82%) and precision (R.S.D 17 %). Decision limit (CCα) and detection capability (CCβ) was 0.05 μg L⁻¹ and 0.09 μg L⁻¹ respectively. The method met the criteria set out in Commission Decision 2002/657/EC for the purpose of confirmation in terms of retention time and ion ratio in the whole range of its application. Conclusions: The developed method is specific and sensitive, suitable for measuring the natural level of testosterone in blood of cattle and for use in routine control programme for the detection of this hormone in bovine serum.
Afficher plus [+] Moins [-]Development of LC-MS/MS confirmatory method for the determination of testosterone in bovine serum Texte intégral
2017
Woźniak Barbara | Matraszek-Żuchowska Iwona | Witek Sebastian | Posyniak Andrzej
Introduction: In the European Union the use of steroid growth promoters is prohibited under Council Directive 96/22/EC. For effective control of illegal use of natural steroids, highly sensitive analytical methods are required, because sex hormones can be present in very low concentrations in biological samples. The aim of the study was to develop a confirmatory method for the detection of testosterone in bovine serum at ppt level.
Afficher plus [+] Moins [-]Levels of the natural hormones 17β-oestradiol and testosterone in serum of cattle: results from population studies in Poland Texte intégral
2016
Woźniak-Sobczak, Barbara | Witek, Sebastian | Matraszek-Żuchowska, Iwona | Kłopot, Alicja | Posyniak, Andrzej
Levels of the natural hormones 17β-oestradiol and testosterone in serum of cattle: results from population studies in Poland Texte intégral
2016
Woźniak-Sobczak, Barbara | Witek, Sebastian | Matraszek-Żuchowska, Iwona | Kłopot, Alicja | Posyniak, Andrzej
Introduction: The present study is a comprehensive overview of the natural occurrence of 17β-oestradiol and testosterone in serum of cattle in Poland. Material and Methods: The serum samples (n = 826) were collected from cattle within five years. The samples were examined for the presence of oestradiol and testosterone using ELISA or gas chromatography with mass spectrometry. Results: In 98 samples (24%) 17β-oestradiol was detected above decision limits of applied methods, including five samples over the recommended concentration of 0.1 μg L⁻¹. Of the serum samples taken from cows (≤18 months of age), 95 and 99 percentiles of the animals had 17β-oestradiol concentration below 0.027 and 0.086 μg L⁻¹ and of samples from cows over 18 months of age - below 0.059 and 0.125 μg L⁻¹ respectively. Calculated values for bulls (≤18 months of age) were 0.025 and 0.034 μg L⁻¹ and for the animals older than 18 months of age - 0.035 and 0.041 μg L⁻¹. The natural presence of testosterone was detected in 201 serum samples (48.7%). According to the obtained data, 95% and 99% of cows (≤18 months of age) serum samples had testosterone concentration below 0.05 and 0.23 μg L⁻¹ and the animals over 18 months of age - 0.30 and 0.49 μg L⁻¹, respectively. For bulls these values did not depend on the age of the animals and were in the ranges of 5 - 6.3 μg L⁻¹ (95%) and 11.4 - 12.1 μg L⁻¹ (99%). Conclusion: Our study showed that the threshold values for these hormones in plasma of cattle designated years ago are correct, but they need to be supplemented for animals older than 18 months.
Afficher plus [+] Moins [-]Levels of the natural hormones 17β-oestradiol and testosterone in serum of cattle: results from population studies in Poland Texte intégral
2016
Woźniak Barbara | Witek Sebastian | Matraszek-Żuchowska Iwona | Kłopot Alicja | Posyniak Andrzej
Introduction: The present study is a comprehensive overview of the natural occurrence of 17β-oestradiol and testosterone in serum of cattle in Poland. Material and Methods: The serum samples (n = 826) were collected from cattle within five years. The samples were examined for the presence of oestradiol and testosterone using ELISA or gas chromatography with mass spectrometry. Results: In 98 samples (24%) 17β-oestradiol was detected above decision limits of applied methods, including five samples over the recommended concentration of 0.1 μg L-1. Of the serum samples taken from cows (≤18 months of age), 95 and 99 percentiles of the animals had 17β-oestradiol concentration below 0.027 and 0.086 μg L-1 and of samples from cows over 18 months of age - below 0.059 and 0.125 μg L-1 respectively. Calculated values for bulls (≤18 months of age) were 0.025 and 0.034 μg L-1 and for the animals older than 18 months of age - 0.035 and 0.041 μg L-1. The natural presence of testosterone was detected in 201 serum samples (48.7%). According to the obtained data, 95% and 99% of cows (≤18 months of age) serum samples had testosterone concentration below 0.05 and 0.23 μg L-1 and the animals over 18 months of age - 0.30 and 0.49 μg L-1, respectively. For bulls these values did not depend on the age of the animals and were in the ranges of 5 - 6.3 μg L-1 (95%) and 11.4 - 12.1 μg L-1 (99%). Conclusion: Our study showed that the threshold values for these hormones in plasma of cattle designated years ago are correct, but they need to be supplemented for animals older than 18 months.
Afficher plus [+] Moins [-]The markers of stress in swine oral fluid Texte intégral
2021
Giergiel, Marta | Olejnik, Małgorzata | Jabłoński, Artur | Posyniak, Andrzej
The markers of stress in swine oral fluid Texte intégral
2021
Giergiel, Marta | Olejnik, Małgorzata | Jabłoński, Artur | Posyniak, Andrzej
The study measured the hormonal and protein markers of acute stress, those of oxidative stress and total antioxidant capacity (TAC) in swine oral fluid, determined which of these parameters would be the most appropriate for future livestock welfare assessment and established the time when the samples should be taken. Stress was induced in 7 out of 14 castrated six-week-old Danbred×Duroc pigs by immobilisation on a nasal snare at 8 a.m., 1 p.m., and 6 p.m. and samples were taken both directly after the stressor was applied and 30 min later. The remaining pigs were the control group, which were not immobilised; their samples were taken at the same times. The concentrations of hormones and malondialdehyde (MDA) were measured using liquid chromatography with tandem mass spectrometry, while those of alpha-amylase and TAC were measured using spectrophotometry. The levels of cortisol and cortisone increased with statistical significance immediately after the acute stress response and 30 min later. A cut-off value set at 0.25 ng/mL cortisol concentration was capable of distinguishing between the stressed and control groups with 100% accuracy in evening samples and 95% accuracy overall. Prednisolone was not present, and the levels of testosterone and corticosterone were low and not distinctive. Alpha-amylase became significantly more concentrated during stress induction and 30 min later. The TAC and MDA levels rose after the stress but without statistical significance. The most suitable markers of acute stress were cortisol, cortisone and alpha-amylase. Oral fluid is a reliable material for monitoring the level of pigs’ stress and should be collected in the evening.
Afficher plus [+] Moins [-]The markers of stress in swine oral fluid Texte intégral
2021
Giergiel Marta | Olejnik Małgorzata | Jabłoński Artur | Posyniak Andrzej
The study measured the hormonal and protein markers of acute stress, those of oxidative stress and total antioxidant capacity (TAC) in swine oral fluid, determined which of these parameters would be the most appropriate for future livestock welfare assessment and established the time when the samples should be taken.
Afficher plus [+] Moins [-]