[Morphometry of bovine luteal tissue explants after the addition of various doses of 15-glycol cloprostenol (Glystrophan inj. Spofa)]. / Morfometrie explantátu luteální tkáne krav po adici ruzných dávek 15-glykal cloprostenolu (Glystrophan inj. Spofa).

Histological and morphometrical examinations were made to investigate the explants of yellow bodies in four gravid cows slaughtered the seventh day after PMSG superovulation and after artificial insemination. The medium of luteal tissue explants was added the test substance 15-glycal cloprostenol at doses of 2.5; 25 and 250 micrograms per ml of the medium. Parallelly cloprostenol in the Oestrophan inj. Spofa preparation was investigated at a dose of 25 micrograms per ml of the medium. The action of the medium lasted 24 hours at temperatures of 37 and 24 degrees C. Besides an overall histological examination the following morphometric indicators were studied: total counts of luteal cells per 1 mm2 area, average area of luteal cells and their nuclei and determination of the nucleocytoplasmic ratio of these cells, parenchymal area (area of luteal cells and stroma) of the luteal tissue per 1 mm2 area. The examinations have indicated that 15-glycal cloprostenol at a dose of 25 micrograms per ml of the medium has stimulating, luteotropic effects on the luteal tissue. The effects were manifested by luteal tissue hyperplasia and the largest area of luteal tissue parenchyma. On the other hand the effects of a tenfold higher dose (250 micrograms per ml of the medium) of the same substance were luteolytic similarly like those of parallelly tested cloprostenol.

[Comparison of the effects of tercleucine and tryptophan superanalogs of LH-RH on gonadotropin secretion in heifers]. / Porovnání úcinku tercleucinového a tryptofanového superanalogu LH-RH na sekreci gonadotropinu u jalovic.

In six heifers without sexual organs the effects were compared of the superanalogues LH-RH [(D-Tle6) and (D-Trp6)] on the secretion of luteinizing hormone (LH) and follicles of stimulating hormone (FSH). The superanalogues were given i. m. at dosages of 10, 50 and 100 micrograms pro toto. Dosages of 50 and 100 micrograms of both superanalogues had a greater effect on the secretion of LH than the dosage of 100 micrograms. The highest average concentration of LH during the time of application (D-Tle6) was recorded in the dosage of 10 micrograms (7.84 ng.ml-1). The average concentrations of LH after application (D-Trp6) were within the range of 5.46 to 9.29 ng.ml-1. Because of the great variability of the concentrations of LH no significant differences were ascertained due to the influence of dosage. From a comparison of the concentrations of LH with the same dosage it emerged that (D-Trp6) after an application of 50 micrograms significantly increased the concentration of LH from the 60th to the 240th minute and thus had a more protracted effect. With dosages of 10 and 100 micrograms of the superanalogues no statistically significant differences were recorded after two hours from application. With (D-Trp6) the higher stimulative effect on the secretion of LH was statistically confirmed. The highest concentrations of follicles of stimulation hormone (FSH) (204.6 and 228.6 ng.ml-1) were found from the 40th to the 100th minute after the application of dosages of 50 and 100 micrograms (D-Tle6). The protracted effect was greatest with a dosage of 100 micrograms (270 mins). (D-Trp6) at a dosage of 100 micrograms caused the greatest effect on the secretion of FSH (226.8 ng.ml-1 for a period of 180 mins). The lower dosages of analogues scarcely differed in response. The dosage of superanalogues has an influence on the concentration of FSH in peripheral blood and on the duration of the protracted effect.

[Concentration of chloramphenicol in blood, organs, and eggs of poultry after the administration of Chronicin solution ad usum vet. (SPOFA)]. / Koncentrace chloramfenikolu v krvi, orgánech a vejcích drubeze po aplikaci prípravku Chronicin solutio ad usum vet. (SPOFA).

The preparation Chronicin solutio ad usum vet. (SPOFA) (a 15% solution of CHF-base in propylene glycol) is to be orally administered to poultry in drinking water. The recommended doses (5 ml per 1 of water in chickens and turkey-poults and 3 ml per 1 of water in ducklings) produce, in the blood serum, CHF concentrations which act bacteriostatically on sensitive microbial strains [chickens--mean 2.60 micrograms per ml (0.71--6.25), ducks--mean 2.11 micrograms per ml (0.87--4.72)]. After dilution, the preparation is stable in the drinkers at least 24 hours and does not reduce the intake of drinking water in short-term administration. CHF residues remained in the organs of hens six days after the five-day therapy and in the eggs of hens nine days after the therapy. It is recommended, therefore, to respect a nine-day protective period in tissues and a 12-day protective period in eggs (between the end of therapy and processing for consumption).