We assessed the possible protective effects of N-acetylcysteine (NAC) against toxic damage in the rat colon. Two doses of NAC (20 mg/kg and 100 mg/kg) given for 2 days and 7 days after acetic acid administration (to induce colitis) were tested. NAC was dissolved in saline and administered locally (intracolonic), systemically (intraperitoneal) or in a combination (intracolonic and intraperitoneal). Several parameters, including macroscopic and histopathological scores and myeloperoxidase, glutathione and nitric oxide concentrations were measured using standard assay procedures. Treatment with 100 mg/kg NAC for 7 days significantly decreased tissue myeloperoxidase, glutathione and nitric oxide concentrations. The 20 mg/kg dose had no protective effects. The data indicate that NAC substantially reduced the degree of colonic injury, probably by regulating free radical production and inhibiting inflammation. It may, therefore, have a role in the treatment of inflammatory bowel disease.

In the study, the relationship of follicular growth waves, oestradiol and pregnancy rates were investigated during oestrus cycle in cows. A total of 22, Brown Swiss cows (3-5 years old) were used for the study. The ovaries of animals were examined from sixth day of cycle to next oestrus by ultrasound. The follicles that were present in the ovarium were recorded. Follicular growth was observed every day by means of ultrasound examination. The blood samples were taken for analysis of oestradiol simultaneously with ultrasound examinations. The oestrus animals were inseminated. Each animal that inseminated was examined by ultrasound on day 28 after insemination for pregnancy diagnosis. Two follicular growth waves were observed in nine of 22 (40.9%), three waves in 13 of 22 (59.1%) animals. The oestradiol was found in the same concentration but in different release patterns between two and three waves animals. Pregnancy rate in cows with three and two follicular waves did not differ. In conclusion, emergence of three waves of follicular growth was higher in Brown Swiss cows, the analysis of oestradiol could be used for determination of the wave numbers and the animals with different waves may have had the same pregnancy rates.

RESuMENEn el presente estudio se investigaron los efectos de la paratuberculosis subclínica en las concentraciones séricas de betacaroteno y retinol en ganado lechero. Se utilizaron 30 vacas lecheras multíparas y no vacunadas de raza Holstein, de 3 a 9 años de edad. 15 de las 30 vacas fueron diagnosticadas subclínicamente positivas a paratuberculosis mediante PCR (grupo 1). Las 15 vacas restantes fueron clasificadas como grupo control (grupo 2) que estaba sano. Los niveles de retinol y de betacaroteno del suero fueron analizados por análisis colorimétrico en todas las muestras. No hubo diferencias con respecto a las concentraciones de retinol y de betacaroteno de suero entre los grupos.