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1.
The plasma concentrations of progesterone and oestradiol-17p during pregnancy and the first 20 days after parturition were estimated in reindeer. The concentration of progesterone in the period 75–25 days prior to parturition was significantly higher than in the period 200– 75 days prior to parturition (P < 0.001). During the last 25 days before parturition the concentration decreased significantly. The concentration of oestradiol-17β was in most cases below 70 pg/ml until 50 days prior to parturition. During the last 25 days of pregnancy there was a significant increase in oestradiol-17β and the ratio progesterone/ oestradiol-17β was markedly lower than in the period 75–25 days before calving.Key words: reindeer, gestation, plasma, progesterone, oestradiol-17β  相似文献   

2.
Changes in the diameters of individual follicular structures on ovaries were measured by transrectal ultrasonography for 29 to 40 days and the plasma concentrations of luteinising hormone (LH), follicle-stimulating hormone (FSH), progesterone and oestradiol 17β were determined in four cows with ovarian cysts. When these structures decreased in size, new follicular structures appeared and developed into cysts. Progesterone concentrations in plasma were below 1·0 ng ml−1 during the experimental periods. Plasma concentrations of oestradiol-17β fluctuated. The mean concentration of oestradiol-17β in plasma differed (P<0·01) depending on the stage of the cyst. No preovulatory surges of LH were detected during the developmental stage of the cysts.  相似文献   

3.
This study characterised the peripheral plasma concentration of PSP-60 throughout gestation, and examined the effect of stage of gestation and foetal number on this protein in Holstein cows after non-surgical embryo transfer. Cows (n=12) were divided into two groups; Group 1 contained single embryo recipient cows (n=5), Group 2 contained twin-embryo recipient cows (n=7). Blood was collected approximately every third day from day 0 (first day of standing oestrus), then daily for the last 10 days of gestation and until one day post-partum. Two of the twin-embryo recipient cows had abnormal pregnancies, consequently data from them was considered separately. In both groups PSP-60 increased progressively from about day 20 post-oestrus to 20 days pre-partum (from 0·9 ± 0·2 to 49·7 ± 8·7 ng ml−1, and from 1·3 ± 0·6 to 115 ± 34·9 ng ml−1 (mean ± SEM), in singleton and twin-bearing groups, respectively). The mean concentrations between 20 and 10 days pre-partum increased dramatically by about six-fold (P<0·001) in singleton-bearing cows (from 49·7 ± 8·7 ng ml−1 to 2838 ± 73·7 ng ml−1) to over two-fold in twin-bearing cows (from 115 ± 34·9 ng ml−1 to 284 ± 98·2 ng ml-1). The mean concentrations of the two groups were indistinguishable between 10 days pre-parturn and parturition. Cows giving birth prematurely to stillborn calves or to a schistosomus reflexus calf exhibited abnormal PSP-60 profiles. Our findings indicate that peripheral plasma PSP-60 concentrations are correlated to the stage of gestation and foetal number, and assist in predicting foeto-placental viability.  相似文献   

4.
Six veal calves were medicated with clenbuterol at 20 μg kg bodyweight−1 day−1 for 42 days before they were slaughtered, to evaluate the lesions and residues in target organs. Compared with six unmedicated calves the most noticeable changes were tracheal dilatation, decreased uterine weight, slight mucous hypersecretion in the uterus and vagina and depletion of liver glycogen. The highest concentrations of clenbuterol (62 to 128 ng/g−1) were recorded in the choroid/retina, and the aqueous humour had the lowest concentration (0·5 to 2·4 ng ml−1). The residue concentrations were higher than the maximum residue level set for clenbuterol (0·5 ng g−1)  相似文献   

5.
Ureaplasma species were isolated from semen samples collected sequentially from one Awassi and three Assaf breeding rams. Each ram was injected subcutaneously with an aqueous solution of lincomycin and spectinomycin for five consecutive days at a dose equivalent to 4·5 mg kg−1 lincomycin and 9·0 mg kg−1 spectinomycin daily. Serum and semen samples were collected at intervals during the treatment and assayed for lincomycin. No Ureaplasma species were isolated from semen samples collected during the course of the treatment and at intervals for 17 days after the last treatment. The concentration of lincomycin in semen ranged from 0·51 μg ml−1 four hours after treatment to 0·08 μg ml−1 24 hours after treatment, and these levels were three to nine times higher than the corresponding serum concentrations.  相似文献   

6.
Plasma concentrations of oestradiol-17ß, progesterone, 15-keto–dihydro–PGF2α and luteinizing hormone (LH) were monitored in llamas and alpacas after mating with an intact male. Concentrations of LH and PGF2α metabolite were high immediately after copulation. Ovulation occurred in 92% of the animals. The first significant increases in progesterone were recorded on day 4 after mating. In non-pregnant animals the lifespan of the corpus luteum was estimated to be 8–9 days. Luteolysis occurred in association with the release of PGF2α. In pregnant animals, a transient decrease in progesterone concentrations was observed between days 8 and 18 in both species. No significant changes in PGF2α secretion were registered during this period. Oes– tradiol–17ß concentrations were high on the day of mating, declined to low values on day 4, and started to increase again on day 8. Peak values after luteolysis in non-pregnant animals were significantly higher than those registered in pregnant ones. Furthermore, concentrations of oestradiol-17ß were elevated for a longer period in non–pregnant than in pregnant animals. The results suggest that progesterone from the corpus luteum exerts a negative influence on follicular activity in pregnant animals by reducing oes– tradiol-17ß secretion.  相似文献   

7.
Oestradiol-17β and testosterone blood plasma concentrations were measured in dogs with Leydig-cell tumours (n=20), Sertoli-cell tumours (n=6), seminomas (n=9), unilateral inguinal cryptorchidism (n=7), abdominal cryptorchidism (n=9, one bilateral), degenerate scrotal testicles (n=6, two bilateral), and animals with normal scrotal testicles (n=20). The testosterone/oestradiol ratio (testosterone concentration [ng/mL] × 100/oestradiol concentration [pg/mL]) was calculated.A considerably higher oestradiol concentration was found in dogs with Sertoli-cell tumours (29.0, 14.4–48.3 pg/mL; median, minimum–maximum; P=0.0256, Mann–Whitney test) and lower oestradiol levels were found in animals with seminomas (12.0, 3.4–17.6 pg/mL; P=0.0025) compared to the healthy control group (18.0, 8.6–31.5 pg/mL). Testosterone concentration was decreased in dogs with Sertoli-cell tumours (0.08, 0.03–0.77 ng/mL) when compared to the control group (1.95, 0.05–3.70 ng/mL; P=0.0012). Testosterone/oestradiol ratios differed from the control (9.6, 0.58–35.8) only in dogs with Sertoli-cell tumours (0.32, 0.06–2.80; P=0.0005). Clinical signs of feminization were observed in five dogs with Sertoli-cell tumour and one dog with a Leydig-cell tumour, and were more often associated with decreased testosterone/oestradiol ratios than with an increased oestradiol-17β concentration.  相似文献   

8.
The single-dose disposition kinetics of marbofloxacin (MBX) were determined in clinically healthy loggerhead sea turtles (n = 5) after oral (PO) administration of 2 mg kg−1 bodyweight. Marbofloxacin plasma concentrations were determined by DAD–HPLC (LOD/LOQ 0.015/0.05 μg ml−1). Data were subjected to non-compartmental analysis. Following PO administration, marbofloxacin achieved maximum plasma concentrations of 11.66 ± 2.53 mg L−1 at 15.00 ± 3.00 h. The absence of general adverse reactions in the turtles of the study, and the favourable pharmacokinetic properties (long half-life and high maximum plasma concentration) of MBX administered PO at the single-dose of 2 mg kg−1 suggest the possibility of its safe and effective clinical use in loggerhead sea turtles.  相似文献   

9.
The pharmacokinetics of orphenadrine (ORPH) following a single intravenous (i.v.) dose was investigated in six camels (Camelus dormedarius). Orphenadrine was extracted from the plasma using a simple sensitive liquid–liquid extraction method and determined by gas chromatography/mass spectrometry (GC/MS). Following i.v. administration plasma concentrations of ORPH decline bi-exponentially with distribution half-life (t1/2α) of 0.50 ± 0.07 h, elimination half-life (t1/2β) of 3.57 ± 0.55 h, area under the time concentration curve (AUC) of 1.03 ± 0.10 g/h l−1. The volume of distribution at steady state (Vdss) 1.92 ± 0.22 l kg−1, volume of the central compartment of the two compartment pharmacokinetic model (Vc) 0.87 ± 0.09 l kg−1, and total body clearance (ClT) of 0.60 ± 0.09 l/h kg−1. Three orphenadrine metabolites were identified in urine samples of camels. The first metabolite N-desmethyl-orphenadrine resulted from N-dealkylation of ORPH with molecular ion m/z 255. The second N,N-didesmethyl-orphenadrine, resulted from N-didesmethylation with molecular ion m/z 241. The third metabolite, hydroxyl-orphenadrine, resulted from the hydroxylation of ORPH with molecular ion m/z 285. ORPH and its metabolites in camel were extensively eliminated in conjugated form. ORPH remains detectable in camel urine for three days after i.v. administration of a single dose of 350 mg orphenadrine aspartate.  相似文献   

10.
Injections of mild irritants intradermally (carrageenan, zymosan and dextran) and intracaveally (carrageenan)in a tissue cage model of inflammation were used in studies of the pharmacodynamics and pharmacokinetics of tolfenamic acid administered intramuscularly in calves. Inhibition of serum thromboxane (TX) B2 and inflammatory exudate prostaglandin (PG) E2 were used as indicators of the magnitude and time course of blockade of cyclo-oxygenase isoforms COX-1 and COX-2, respectively. Single doses of 2, 4 and 8mgkg−1 tolfenamic acid partially inhibited irritant-induced rises in skin temperature (non-dose dependently) and skin oedema (dose-dependently). These doses also markedly inhibited serum TXB2 synthesis and the duration of inhibition was dose-related. A dose of 2mgkg−1 tolfenamic acid also attenuated skin temperature rise over carrageenan-injected tissue cages, and markedly inhibited exudate PGE2 synthesis, even though drug penetration into both exudate and tissue cage transudate was limited. Tolfenamic acid pharmacokinetics were characterized by a relatively short tmax (0.94–2.0411), a high estimated Vdarea (1.79–3.20Lkg−1), an estimated ticase 1/2β of 8.01–13.5011 and Clβ of 0.142–0.175Lkg−1h−1. The actions of tolfenamic acid in inhibiting PGE2 synthesis and in attenuating two of the cardinal signs of inflammation (heat and swelling) suggest that a dosage of 2mgkg−1 administered intramuscularly should be effective clinically as an anti-inflammatory agent.  相似文献   

11.
Endotoxaemia is a leading cause of death among horses. Thrombocytopenia is a common finding in clinical and experimentally-induced cases of endotoxaemia and can lead to coagulopathies, including disseminated intravascular coagulopathy which is usually fatal. In this study it was shown that endotoxin (3 ng ml−1 to 25 μg ml−1) can aggregate equine platelets in heparinised whole blood in vitro. The endotoxin-induced aggregation (EIA) was shown to be dependent on the presence of leucocytes in the blood and did not occur when detoxified endotoxin was used, suggesting that lipid A was necessary for the response. Aspirin (1 mmol litre−1) had no effect on EIA whereas apyrase (40 μg ml−1) completely abolished it and CV3988 (3 to 30 μmol litre−1) (a competitive antagonist of platelet-activating factor) inhibited the response in a concentration-dependent manner. It is concluded that endotoxin activates equine platelets at low concentrations through an indirect mechanism that involves calcium, leucocytes, adenine nucleotides and platelet-activating factor.  相似文献   

12.
The concentrations of LH, FSH, oestradiol-17beta and progesterone in the blood plasma of the female Bactrian camel (Camelus bactrianus) before and after intramuscular injection of seminal plasma.  相似文献   

13.
Plasma lactate concentrations were studied in 17 (11 Standardbred and six Thoroughbred), healthy racehorses following a standardized exercise test on a high-speed treadmill. Blood samples were collected from the jugular vein and placed into tubes containing lithium heparin at intervals throughout the test The blood was immediately centrifuged for 10 minutes at 3000 rpm and the plasma removed. Plasma lactate concentrations were measured using the Accusport and a commercial spectrophotometric method. Prepared lactate standards in the ranges 5 to 45 mmol. 1−1 were also tested using these methods. Samples with lactate concentrations greater than 10 mmol. 1−1 were diluted with double de-ionized water such that the estimated lactate concentration did not exceed 10 mmol. 1−1. Accusport correlated highly with the wet chemistry method at concentrations less than 13 mmol. 1−1 (r=0.983, P<0.001) for undiluted plasma and 20 mmol. 1−1 (r=0.988, P <0.001) for prepared standards. Accusport underestimated lactate concentrations for plasma samples greater than 13 mmol. 1−1 (r=0.313, P>0.05). Accusport continued to correlate significantly with the wet chemistry method, for prepared standards, at lactate concentrations greater than 20 mmol. 1−1 (r=0.940, P<0.01), however the line of fit was significantly different from the line of unity indicating a lack of accuracy for the Accusport at lactate concentrations greater than 20 mmol. 1−1. Diluted lactate samples correlated significantly with the wet chemistry method at the P<0.05 level (r=0.625), however the line of fit was significantly different from the line of unity at the P<0.1 level.  相似文献   

14.
Blood acid-base and electrolyte status was studied in four sedentary Miniature Horses treated with 200, 300, 400 and 500 mg of sodium bicarbonate (NaHCO3) per kg of body weight (BW). Arterial blood was collected before treatment with NaHC03 and each hour for 5 h after treatment. All treatments resulted in an increase in blood pH, bicarbonate (HCO3−) concentration and base excess (BE) by 1 h post-dosage, which continued through the 5th hour (P < .05). Treatment with 200 mg NaHC03/kg BW resulted in less elevated blood HCO3− concentrations (P < .03) and BE values (P < .01) when compared to the other treatments. Following dosing with NaHCO3, plasma Na+ concentrations increased among all treatments but declined to initial values by 3 h post-treatment. The 200 mg NaHCO3/kg BW dosage resulted in the smallest increases in plasma Na+ concentrations (P < .03). Both plasma K+ and Ca++ concentrations were lower (P < .05) among all treatment groups 1 h post-dosage but returned to initial values by 5 h and 3 h posttreatment, respectively, with no differences (P >.05) among treatments. All NaHCO3 dosages increased blood buffering capacity as indicated by increased blood pH, HCO3− concentration and BE. Maximum blood pH, HCO−3 concentration and BE was reached using a dosage of 300 mg NaHCO3/kg BW. Also, all treatments altered the plasma electrolyte concentrations.  相似文献   

15.
The effects of cholecystokinin-8 (cck-8) and pentagastrin on insulin and glucagon secretion were studied in conscious sheep. Intravenous infusions of ccx-8 (3 to 1000 pmol kg−1 min−1 for 30 minutes) induced a dose-dependent increase in plasma insulin, but did not alter plasma glucagon concentration. The threshold dose of ccx-8 for stimulation of insulin secretion was 10 to 30 pmol kg−1 min−1. Pentagastrin was infused intravenously at doses of 10 to 3000 pmol kg−1 min−1. The maximal dose of pentagastrin slightly stimulated insulin, but not glucagon, secretion. The insulin secretory activity of pentagastrin was only 1/300 that of ccx-8 on a molar basis. The threshold dose of ccx-8 for stimulation of insulin secretion was similar to that for exocrine pancreatic secretion obtained in earlier studies. In conclusion, ccx is a potential candidate as a physiological factor regulating insulin secretion in sheep.  相似文献   

16.
Serum testosterone concentrations and the spermiograms of prepuberal bulls fed two levels of protein diets were investigated at 7, 10, 14 and 18 months of age. Scrotal circumference, body condition score and total sperm counts of those animals on a high protein diet were significantly (P <0.05) higher than those on a low protein diet. However, sperm motility, total dead sperm and abnormal sperm did not differ between the treatment groups (P <0.05). One bull fed a high protein diet had significantly higher testosterone concentrations (basal and peak) than a bull fed low protein throughout the four sampling periods (P <0.05). Testosterone concentrations, scrotal circumference, volume of semen, sperm concentration and sperm output of bulls on low and high protein diets increased significantly with age (P <0.05). Peak testosterone concentrations ranged from 1.1. ng ml−1 at 7 months to a maximum of 5.3 ng ml−1 at 18 months. The 24 h secretory patterns of testosterone were episodic, pulsatile or temporal in nature. The peaks occurred mostly in the morning hours and ranged from one to five in number. Protein intake in prepubertal bulls could have significant influence on spermiogram and testosterone production.  相似文献   

17.
Fifteen Holstein cows were treated with two doses of 25 mg of a prostaglandin F2α (PGF2α as dinoprost tromethamine) administered intramuscularly 11 days apart. The cows were then divided into three groups and inseminated either at 72, 80 or 72 and 96 hours after the second dose of PGF2α. Thirteen cows ovulated after the second prostaglandin treatment. Eight cows were diagnosed pregnant by rectal palpation 42 days after insemination but only five calved. PGF2α induced luteolysis in cows with active corpora lutea as evidenced by the dramatic decreases in the plasma progesterone concentrations after treatment. In contrast, following PGF2α administration to cows in follicular or late luteal phase the concentrations of plasma progesterone either increased gradually or remained low for several days before increasing to maximal levels. The ovulatory rate after the two doses of PGF2α11 days apart was high. However, the pregnancy rate after this treatment was influenced by other factors including abnormal ovarian function.  相似文献   

18.
The activities of danofloxacin, a novel fluoroquinolone, and two other antimicrobials were determined in vitro against field isolates of seven Mycoplasma species of veterinary importance isolated from cattle, swine and poultry in five European countries. The minimum inhibitory concentrations (MIC) of danofloxacin, tylosin and oxytetracycline were determined against a total of 68 isolates. Danofloxacin showed excellent activity against isolates of all Mycoplasma species (range 0·008 to 0·5 μg ml−1), but in some isolates there was evidence of reduced sensitivity to tylosin (range 0·008 to 2·0 μg ml−1) and oxytetracycline (range 0·008 to over 16·0 μg ml−1). Danofloxacin was more active than other antimicrobials against, M hyopneumoniae, M dispar and M bovigenitalium, and showed activity similar to that of tylosin against M bovis and M gallisepticum. Tylosin was the most active against M synoviae and M hyosynoviae. Generally, oxytetracycline showed the poorest activity, but was superior to tylosin against M bovigenitalium. A second (final) MIC reading was taken for all isolates 14 or 21 days after the initial reading, and MIC values rose during that time. However, the increase seen in danofloxacin values (typically one to two dilutions) was less than that seen for tylosin and oxytetracycline. It is concluded that danofloxacin is highly active in vitro against all of the Mycoplasma species tested, and thus shows great potential for the treatment of respiratory and other infections caused by Mycoplasma species in cattle, pigs and poultry.  相似文献   

19.
Gentamycin sulphate ( ) and gentamycin oleate ( ) were encapsulated in liposomes composed of phosphatidylcholine ( ) and cholesterol ( ) (molar ratio 7:7:2 and 5:5:l, respectively), and were administered via intramuscular injection to rabbits, to evaluate their potential use as sustained release formulations. Five groups of five animals each were used for the pharmacokinetic study, and treatments were established as follows: 3 mg kg−1 of i.v., 3 mg kg−1 of i.m., 3 mg kg−1 of liposome-containing gentamycin sulphate ( ) i.m., 3 mg kg−1 of i.m., and 3 mg kg−1 of liposome-containing gentamycin oleate ( ) i.m. Gentamycin plasma concentrations after i.m. administration of LGS were extremely low compared with those obtained after the i.m. administration of ; the peak plasma concentration ( max) showed an eight-fold decrease with , and the area under the concentration-time curve ( ) was four-fold lower for the liposomal form. The apparent elimination half-life estimated after administration of showed a three-fold increase compared with values calculated for free . After the administration of the same dose of , max obtained showed a 2·5-fold decrease in relation to peak concentrations of free , and the apparent β-half life of encapsulated showed a three-fold increase compared with i.m. . Large-size liposomes containing gentamycin administered i.m. to rabbits gave sustained drug release from the injection site, providing prolonged plasma concentrations of the drug in the body.  相似文献   

20.
Bovine serum amyloid-A (b-SAA) was purified from a pool of acute phase serum using hydrophobic interaction chromatography and gel filtration. Serum was applied at a low salt concentration to a phenyl-sepharose column and SAA was eluted with a gradient of 0 to 6 M guanidine-HCI. Fractions containing SAA were pooled, concentrated and further purified by gel filtration on Superose-12. The concentration of SAA in bovine serum was quantified by an indirect ELISA using rabbit anti-human SAA and horseradish peroxidase conjugated donkey anti-rabbit IgG. Dilutions of an acute phase bovine serum sample were used as working standards. The SAA concentration of this standard was determined by comparison with purified b-SAA on SDS-polyacrylamide gel electrophoresis followed by densitometry at 590 nm. The assay detection limit was 3 μg ml−1; the intra-assay coefficient of variation was 4 per cent and interassay coefficients of variation were 5·5 per cent and 7·2 per cent at 66 and 178 μg ml−1 SAA, respectively. In calves experimentally infected with Pasteurella haemolytica type A1 the ELISA was able to detect a 10-fold increase of SAA within 24 hours of inoculation.  相似文献   

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