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Biomedical subjects

M Tokos

Publications and source records attributed to M Tokos.

15 recordsLinked to original sources
PubMed1990

[Superovulation induction in sheep using PMSG].

The effects of application of differentiated PMSG rates (Antex Leo, Denmark) were investigated in 30 ewes of the Slovak Merino breed in the period of May--June in experimental conditions on the induction of superovulation and on the speed of egg transport through the sexual organs. After administration of PMSG at rates of 750, 1000 and 1500 i. u. per head/day, increases were recorded in the average weight of ovaries, number of large follicles and ovulations. Flushing the eggs from different parts of the sexual organs indicated that the higher the PMSG rate, the faster was the egg transport.

Animals↗
PubMed1990

[Quantitative micromorphological study of the ovaries in sheep after estrus synchronization and superovulation in the autumn mating season].

The quantitative micromorphological changes of tertiary follicles and corpora lutea (CL) were studied in ewes in the autumn mating season after oestrus synchronization, induced by administration of PGF2 alpha (Oestrophan Spofa) at a rate of 125 micrograms, and after superovulation, induced by administration of PMSG (Antex Leo, Denmark) at a rate of 1000 I. U., or PMSG at rates of 750 and 1000 I. U. together with 50,000 I. U. vitamin A (Axerophthol Spofa). The highest number of ovulations was obtained in ewes treated with 1000 I. U. together with vitamin A (3.4 +/- 3.0) and after administration of 1000 I. U. PMSG alone (2.6 +/- 2.74). The highest number of tertiary follicles was recorded in ewes after administration of PGF2 alpha. The proportion of tertiary atretic follicles was the highest in ewes after administration of PMSG (64.6%). The occurrence of the luteinizing form of atresia was recorded only in ewes treated with PMSG (4% of the total number of atretic follicles). Using the caryometric analysis of the luteal cells of corpora lutea, the ewes of the experimental groups had two-peak variation curves; this corresponds to the theory of the presence of two luteal types in the tissue of the corpus luteum in ewes. As determined morphometrically, the smallest proportion of connective tissue out of the total volume of ewes' ovaries was found after administration of 1000 I. U. PMSG together with vitamin A. Administration of vitamin A together with PMSG had a favourable influence on the over-all follicular response, on the average number of ovulations, and on the proportion of non-atretic follicles.

Animals↗
PubMed1990

[Changes in the biometry of the sex organs of sheep after estrus synchronization and superovulation in the breeding period].

In twenty ewes of the Slovak Merino breed coming from a demonstration farm at Zemplínska Teplica, to the age of two-three years biometrical variations of the sex organs and overall follicular response to PMSG and PGF2 alpha administration were investigated in the autumn period (October-November). In the ewes of all groups the heat was synchronized by i. m. administration of PGF2 alpha (Oestrophan Spofa) at a dose of 125 micrograms in the interval of 11 days. On the ninth day the ewes of the second and fourth group were given 1000 i. u. of PMSG (Antex Leo, Denmark), the ewes of the third group 750 i. u. of PMSG. The ewes of the third and fourth group were administered at the same time 50,000 i. u. vitamin A (Axerophtol Spofa) (each group). The weight and dimensions of the sex organs were investigated. The results demonstrate that the administration of PMSG in the mating period increases significantly the weight of oviducts and horns of uterus in the ewes while there are no variations of the weight of the other sex organs and of their length, or it is lower than in the ewes of the control group. The overall follicular response was not influenced by the higher weight of ovaries.

Animals↗
PubMed1990

[The effect of the seasons on the ovarian response in sheep after the administration of the serum gonadotropin, PMSG].

In the autumn oestrus season, 20 Slovak Merino ewes were exposed to synchronization of oestrus, treated with the PGF2alfa at doses 125 micrograms (Oestrophan, inj. Spofa). followed by an injection of PMSG at doses 1000 IU (Antex Leo Denmark) and 50,000 IU of Vitamin A (Axerophtol Spofa). 23 anoestrus ewes were synchronized with an intravaginal sponges containing 20 mg of chlorsuperlutine (Agelin, Spofa) for 12 days and after sponge withdrawal, the ewes were injected with 750 and 1000 IU of PMSG (Antex Leo Denmark). Ovulatory response was observed and the possibility of ova recovered from the genital organs in ewes after synchronization of oestrus and superovulation in oestrus season. Higher values of the total follicular response (CFO), and the average number of ovulation (PO) after administering equal doses of PMSG were found out both in anoestrus ewes (CFO 6.62 +/- 4.24; PO 4.25 +/- 4.52) and in oestrus ewes (CFO 2.70 +/- 2.10; PO 2.60 +/- 1.74; resp. CFO 2.80 +/- 1.83; PO 3.4 +/- 3.0), if the ewes were treated with PMSG together with vitamin A. The average number of ova flushed was higher in anoestrus ewes (3.0-0.5) than in oestrus ewes (1.67-3.75). In both trials the equal ratio in the number of released ova was gained from ewes of experimental groups (83-88% of the total number). After ova flushing from the genital organs in ewes of the experimental groups most ovas were found in the isthmatal part of the uterine tube (36-60%). On the basis of gained results it was concluded, that synchronized oestrus ewes on receiving PMSG in anoestrus season the ovarial response was more significant than in autumn breeding season.

Animals↗
PubMed1989

[Changes in the follicle system and the population of tertiary follicles in sheep after the administration of PMSG in anestrus].

The total quantitative changes of ovaries, proportion of atretic and non atretic follicles and changes of tertiary follicles in sheep after administration of increasing doses of PMSG during the anoestrous period were observed. In experimental groups the statistically significant increase of average weight, volume and dimensions of ovaries in comparison with control group were determined biometrically. The average number of tertiary follicles was greater in experimental groups but at the same time we observed a higher proportion of atretic follicles (64% of the total number in the control group; 71-77% in the experimental groups). In the group of sheep administered a dose of 1500 m.u. PMSG we determined a high proportion of luteinized follicles (as much as 21% of the total number of atretic follicles). The total number of small follicles in the so called transient phase in the comparison of experimental and control groups was not changed significantly. In the experimental group an increased incidence of preovulatory follicles and a reduction of tertiary follicle dimensions in the period of follicle cavity formation was determined.

Anestrus↗
PubMed1989

[Use of nitrovin in feed and its effect on the development of Marek's disease in chickens].

The effect of the Czechoslovak product Nitrovin, administered at a rate of 15 mg per kg of feed mixture, was studied as exerted on the growth activity, meat quality, and the development and intensity of occurrence of patho-morphological changes ascribable to Marek's disease. An increase of weight gains and dressing percentage was recorded in the group of birds given Nitrovin, as well as in those which had Nitrovin in their feed and were infected with a highly virulent virus of Marek's disease. No significant changes occurred in the contents of dry matter and protein, but there was a much lower fat content in breast muscle in the groups of chickens infected with the Marek disease virus. Internal organs were subjected to biometrical measurements. The birds treated with Nitrovin and infected with the highly virulent virus of Marek's disease had significantly lighter hearts and heavier spleens. Liver, nervus ischiadicus, gonads and spleen were affected most intensively by the changes testifying to Marek's disease. The results are just preliminary and the investigation continues.

Animal Feed↗
PubMed1988

[The effect of PMSG on the trypsin inhibitory activity of the blood and cervical mucus and on the reproductive organs in sheep during anestrus].

The effect of the doses of 750, 1000, and 1500 I. U. PMSG (Antex Leo) on changes in the trypsin-inhibition activities (TIA) of the blood plasma and cervical mucus of ewes was found to vary: a) in the times (from PMSG administration) of recording the minimum values of total TIA (72, 48, 24 hours); b) in the values of the average total TIA on individual days of the trial (40.3-141.4% of the control values); c) in the fractions of low-molecular TIA after administration of 750 and 1500 I. U. PMSG, the fractions exhibited minimum values after 24 hours, and of 1000 I. U. after 72 hours (53.0 and 60.4, and 69.7% of the control values, respectively); d) in the highest values of the fractions of low-molecular TIA recorded after 96 hours (96.1-183.7% of the control values); e) in the average values for 96 hours of the trial, which ranged from 64.1% (1500 I. U.) to 77.1% (750 I. U.) for total TIA and from 89.6% (750 and 1000 I. U.) to 122.8% (1500 I. U.) for low-molecular TIA; f) in the ratio of atretic and non-atretic (A/N) tertiary follicles, which grew with increasing PMSG doses; this was indirectly correlated with the average values for total TIA; g) in the weights of uteri and ovaria which increased from 176.8 to 322.3% of the control values after the stimulation; h) in the epithelium thickness of cervix and cervical glands increasing from 118% to 316% of the control values; i) in the average TIA values of cervical mucus ranging from 53.3 to 125% of the control values.

Anestrus↗
PubMed1983

[Karyometric changes in the neurons of the hypothalamic and ependymal nuclei of the 3d cerebral ventricle in sheep after administration of Gn-RH and subsequent irradiation].

Caryometric analysis was used for the study of changes in the cell nucleus volume of the neurons of nucleus paraventricularis, nucleus arcuatus, and ependyma of the third cerebral ventricle of sheep after the administration of Gn-RH, followed by exposure to X-rays. The test animals were 12 ewes in physiological anoestrus and two rams. The trials were conducted in spring. The first group of four sheep and two rams were left as controls; in the ewes of the second group the hypothalamo-hypophysial region was irradiated by exposure to 516.5 mC/kg (200 R); in the four ewes of the third group, ovaries were directly irradiated at laparotomy by exposure to 64.4 mC/kg (250 R). The ewes of the second and third group were treated with an i. m. administration of 400 micrograms Gn-RH per head before irradiation. The excisions were collected and processed the tenth day from irradiation. The studied material was fixed by injection of 10% formalin and finished by another dose of 10% formalin after the excision of the brains. The paraffin slices were stained with haematoxylin-eosine. The caryometric analysis was performed at 3000-fold magnification, 200 cells being measured in each sample. Changes in neurosecretory cells were described in the regions of nucleus paraventricularis, nucleus arcuatus and in the ependyma of the third cerebral ventricle. The results of the caryometric analysis of nucleus paraventricularis and nucleus arcuatus suggest that the administration of Gn-RH and irradiation of the hypothalamo-hypophysial region, and direct irradiation of ovaries, stimulate the studied cerebral structures. The changes observed in the ependyma of the third cerebral ventricle after the administration of Gn-RH and subsequent irradiation of the hypothalamo-hypophysial region are insignificant; it is only after the direct irradiation of ovaries that these cells are inhibited by an indirect effect through the feedback mechanism.

Animals↗
PubMed1983

[The effect of graduated radiation doses on the follicular apparatus of the ovaries and the adenohypophysis in sheep].

Gradually increased radiation doses were applied directly to the ovaries of laparotomized ewes. The effect of these doses was studied as exerted on the qualitative and quantitative changes in the follicular apparatus of the ovaries and adenohypophysis of ewes in anoestrus and upon the recovery processes later on after irradiation. The ovaries irradiated with the dose of 4.79 Gy were found to be heavier when examined after some time from irradiation. The 10th and 30th day from irradiation the number of tertiary follicles decreased, the 100th day from irradiation their number increased to a four-fold level, as compared with the 10th day. Adenohypophysis showed a gradual growth of the number of PAS-positive cells. After the irradiation of ovaries with the dose of 9.57 Gy the ovaries showed the lowest rate of damage on the 10th day from irradiation; the 30th and 100th day from irradiation all the present tertiary follicles were in the state of atresia. In comparison with the control group, the amount of gonadotropic cells of adenohypophysis gradually increased, recovering from a rapid drop after irradiation. When the ovaries were irradiated with the dose of 19.14 Gy, all the tertiary follicles were in the state of atresia and the number of PAS-positive cells of adenohypophysis was lower in comparison with the control group.

Anestrus↗
PubMed1983

[Dynamic changes in the trypsin-inhibiting activity in cervical mucus, blood and in the histomorphological structure of the uterus in x-irradiated sheep].

The effect of ionizing radiation on the reproduction organs of ewes was studied after single local irradiation of ovaries with different X-ray doses. Twenty two ewes of the Slovak Merino breed at the age of two years and at the average live weight of 30 kg were divided into four test groups to be irradiated with the following doses: Group I (n = 6) 4.78 Gy (500 R), group II (n = 6) 9.67 Gy (1000 R), group III (n = 6) 19.14 Gy (2000 R). The ewes of the fourth group were used as the control; they were only laparotomized, otherwise left intact. The trypsin-inhibiting activity of blood plasma and cervical mucus was determined from the retardation of the hydrolysis of low-molecular substrate (TAPA); the thickness of the epithelium of uterine body and cervix was measured microscopically after fixing and staining. The dynamics of changes in the TIA of cervical mucus, in percentual expression, showed differences when measured in the course of 10, 30 and 100 days (1.84 K, aver. for 1st-10th day: 1 = 2.1; 2 = 1.7; 3 = 1.7; 4 = 2.5. Aver. for 10th-30th days: 1 = 1.8; 2 = 1.7; 3 = 1.8; 4 = 1.0. Aver. for 30th-100th day: 1 = 1.7; 2 = 1.1; 3 = 1.2; 4 = 1.5). The dynamics of changes in the thickness of the epithelium of endometrium, uterine horns and uterine cervix had a different nature. A hundred days from irradiation the values showed little difference.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1977

Tertiary follicles in heifers treated with melengestrol acetate.

Qualitative and quantitative changes of tertiary follicles were studied in ovaries of heifers during and after the treatment with melengestrol acetate (MGA--6-methyl-6-dehydro-16-methylen-17alpha-acetoxyprogesteron), the atretic tertiary follicles being classified into several types. During the administration of MGA an increased number of atretic follicles was found as well as a stimulation of glandular cells of theca interna, while after the withdrawal of the drug an increased number of normal tertiary follicles was observed estrous cycle. On the 7th day of MGA administration most of the atretic follicles were in the stage of early atresia and a few only were in the stage of luteinized cystic atresia. On the 14th day, however, most of tertiary follicles were in late atresia and only a few were in early atresia. Moreover, at the same time the number of follicles classified as luteinized cystic atresia was increased, while that of follicles showing cystic follicular atresia was decreased. After the withdrawal of MGA the most numerous group of follicles was in the stage of early atresia. It was demonstrated that the time changes in the number of follicles with a diameter larger than 5 mm resemble that of normal tertiary follicles. During MGA administration the number of follicles with a diameter of 2 to 5 mm was the largest. These findings show that MGA may effect the feed-back regulation of both the cyclic and basal secretion of gonadotropic hormones. After the withdrawal of the drug there may be higher basal secretion of gonadotropins.

Animals↗