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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.
Mostrar más [+] Menos [-]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.
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
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.
Mostrar más [+] Menos [-]Levels of the natural hormones 17β-oestradiol and testosterone in serum of cattle: results from population studies in Poland
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.
Mostrar más [+] Menos [-]Detection of testosterone residues in farm fish tissue
2009
H. R. Abdel-Dayem | Hanaa M. Soltan | G. Naser
A total of one hundred samples of marketed fish farm; 25each of tilapia (Oreochromis niloticus), Mugil cephalus, Carp (Silver) and fry; were collected from different localities at Al- Behera and Kafr El-Shakh Provinces. The samples were examined for detection of testosterone hormone by Thin Layer chromatography (TLC) as well as it was quantitatively assayed by Radio-Immuno-Assay (RIA). The obtained result revealed that the testosterone residues were detected in flesh of farm fish of Tilapia (Oreochromis nilotocus) and Carp (Silver), each constituting 24% and 4 %; respectively but it could be failed to detect in each of Mugil cephalus and fry. The hormonal residues of testosterone was ranged from 3.25 to 34.9 ng/g with mean value 4.22±1.1 ng/g in positive samples of Tilapia, while only one sample of Carp showed 22.0 ng/g, Mugil cephalus and Fry showed no detectable level of hormonal residues. The public health significance of detectable levels was discussed as well as the recommendations to avoid health hazards from such fish were mentioned.
Mostrar más [+] Menos [-]The markers of stress in swine oral fluid
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.
Mostrar más [+] Menos [-]Pituitary-testicular axis dysfunction in methimazole-induced hypothyroidism in rats
2019
Gołyński, Marcin | Metyk, Michał | Szkodziak, Piotr | Lutnicki, Krzysztof | Kalisz, Grzegorz | Szczepanik, Marcin | Wilkołek, Piotr | Dobrowolski, Piotr
Introduction: Thyroid hormones play a major role in the regulation of testicular maturation and growth and in the control of Sertoli and Leydig cell functions in adulthood. When naturally occurring, hypothyroidism causes male hypogonadotropic hypogonadism and Sertoli cell function disorders, but when iatrogenic and methimazole-induced its influence on the pituitary-testicular axis function with respect to Sertoli cells is poorly known. Material and Methods: Male adult Wistar rats (n = 14) were divided into two groups: E – taking methimazole orally for 60 days, and C – control animals. After 60 d, the concentrations in serum of testosterone, follicle-stimulating and luteinising hormones, and inhibins A and B were measured. Testicles were examined morphologically: the apoptotic Sertoli cell percentage (ASC%) and number of these cells functional per tubular mm² (FSCN/Tmm²) were calculated. Results: In group E, inhibin A was higher while inhibin B was lower than in group C. ASC% was higher and FSCN/Tmm² lower in group E than in group C. Conclusion: A specific modulation of Sertoli cell function in the course of methimazole-induced hypothyroidism leads to a simultaneous concentration increase in inhibin A and decrease in B. Inhibin A might share responsibility for pituitary-testicular axis dysfunction and hypogonadotropic hypogonadism in this model of hypothyroidism.
Mostrar más [+] Menos [-]Toxicological evaluation of flumequine in pubertal male rats after oral administration for six weeks
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.
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