The objective of this study was to evaluate the effect of a second prostaglandin F2α (PGF2α) treatment during Ovsynch on luteal regression and fertility in dairy cows, compared with standard Ovsynch. The study was conducted on 111 Holstein Friesian multiparous cows on commercial dairy farm. The cows in the experimental group (n=48) received two treatments of PGF2α 24 hours apart during Ovsynch. The cows in the control group (n=63) were synchronized with standard Ovsynch. To assess the progesterone (P4) concentration blood samples were collected at the day of PGF2α treatment and at the 2nd GnRH treatment. Pregnancy was evaluated by ultrasound examination 37-40 days after timed artificial insemination (TAI) by ultrasound. Cows diagnosed pregnant were re-examined between days 70-80 after TAI. The percentage of cows with complete corpus luteum (CL) regression (P4<0.5 ng/ml at the time of the 2nd GnRH treatment) was 89.6 % after two PGF2α treatments and 88.9 % after one PGF2α treatment. There were no statistically significant differences (p>0.05) in the pregnancies per artificial insemination (P/AI) between the experimental and control group (P/AI). However, the pregnancy loss rate was lower in cows receiving two PGF2α treatments than in the control animals (0.0 % vs. 6.4 %; p<0.05). In conclusion, the second PGF2α treatment during Ovsynch protocol had no significant effect on CL regression and P/AI in dairy cows. The pregnancy losses until days 75-80 after TAI were significantly lower after two PGF2α treatments than after one PGF2α treatment.

In this paper we present the first occurrence of the Diabrotica virgifera Le Conte in Poland and the measures taken against this pest. The specimens of western corn rootworm were found in South-Eastern Poland (Podkarpackie voivodeship) at the end of August and in September of 2005.

Thin film solar cells based on multinary compound Cu(In,Ga)Se2 show record photovoltaic conversion efficiency approaching 20%. Investigation on defect physics in this compound is crucial for making further progress in the technology. In this work we present the results on photocapacitance (PC) and deep level optical spectroscopy (DLOS) for two types of cells – high efficiency Cu(In,Ga)Se2 cell with about 20% of gallium and pure gallium CuGaSe2 device. We show that PC and DLOS, employed as the techniques complimentary to deep level transient spectroscopy DLTS and admittance spectroscopy, are useful methods in providing information on defect levels in solar cells. In particular they are helpful in diffierentiating between levels belonging to the bulk of absorber and to the interface states. We tentatively assign some of the observed deep levels to InCu or GaCu antisites and Cu interstitials.