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European beech seeds are characterised by deep physiological dormancy and to germinate, they require several weeks of stratification at 3°C. Seed dormancy is under hormonal regulation, but the details of how hormones regulate deep dormancy in trees remain not yet well elucidated. We hypothesised that the mechanism of seed dormancy breaking is differentially regulated according to depth of dormancy. Expression of ABI5 and 14-3-3, members of the abscisic acid pathway, and RGL2, a member of gibberellic acid pathways, were examined at the protein and mRNA levels during dormancy alleviation of beech seeds. Unlike in non-deep dormant seeds, ABI5, 14-3-3 and RGL2 were present during nearly all periods of cold stratification in beech seeds, but during dormancy breaking and germination these proteins nearly disappeared. Relative abundances of ABI5 and 14-3-3 transcripts were the highest in dormant dry seeds, and during stratification it decreased gradually. We suppose that during stratification, de novo translation of proteins on the basis of deposited mRNA occurred. On the base of our research we can conclude that the seed dormancy breaking mechanism differs according to seed's dormancy depth. [ABSTRACT FROM AUTHOR]

Aesculus hippocastanum is a well-known species, which is popular because of its ornamental value. However, data on the demographic structure and potential distribution of A. hippocastanum are limited. The invasion of Cameraria ohridella into Europe has harmed those trees growing in artificial sites, but the presence of this insect in natural stands has been little studied. Here we aimed to investigate the demographic structure infestation level of natural populations of horse-chestnut. Additionally, Maxent modelling was used to predict the potential range of A. hippocastanum, based on the localities available in the literature. Field data analysis indicated that natural populations of A. hippocastanum are mostly found nearby mountain streams. The populations showed a diverse height structure and large numbers of seedlings, which indicate high population dynamics. The level of infestation by C. ohridella varied greatly and correlated with altitude. Secondary infestation might explain this infestation variability in some natural populations. Other hypotheses, such as environmental resistance factors or different genetic variability, are also discussed. By spatial distribution modelling, we found that the precipitation of the coldest and warmest quarters, as well as altitude, are important factors influencing the potential distribution of A. hippocastanum. [ABSTRACT FROM AUTHOR]

The objective of this study was to supplement dairy cow diets with a mixture of rapeseed oil and fish oil at a low dose to modulate rumen and milk fatty acids without affecting other rumen fermentation and productive parameters. Our study was carried out on 14 lactating Polish Holstein-Friesian cows during their productive lives. One cow within each group was fitted with rumen cannulas. Animals were subjected to one of the treatments: 1) CON; total mixed ration (TMR) without oil supplementation, 2) FRM; consisting of TMR + 360 g/day/animal of rapeseed oil and fish oil in a 1:1 mixture. Milk production recorded throughout the experiment was not affected by oil mix supplementation; additionally, the whole tract digestibility did not differ when compared with the control group. No negative effects were also observed on the total rumen protozoan population, volatile fatty acids and methanogens; however, total bacterial counts were slightly affected (P>0.05) after 3h of feeding as an immediate effect of oil mix addition, which later disappeared at 6 h post-feeding. Feeding dairy cows with rich sources of long chain polyunsaturated fatty acids at a low dose (360 g/day/animal) resulted in favourable changes in milk fatty acid content without affecting milk fat concentration. Milk from dairy cows fed a diet with oil supplement had more (P>0.05) C18:2 c9t11 and C18:2 t10c12, by 30% and 38%, respectively, when compared to the control group. In addition, the level of supplement used in our study increased the n-3 fatty acids proportion significantly when compared to the control diet. Hence, we can conclude that using 360 g/day/animal (about 1.8% of dry matter intake) positively influenced the milk fatty acid content without any adverse effect on cows' productivity. [ABSTRACT FROM AUTHOR]

The aim of the experiment was to determine the effect of different sources of tannins on the in vitro rumen fermentation with focus on methane production. In the experiment, a rumen simulation system (RUSITEC) equipped with 4 fermenters (1 L) was used in three replicated runs (6 d of adaptation and 4 d of sampling) to study the effects of Quercus cortex extract (QC), Vaccinium vitis idaea (VVI) dried leaf extract and a mixture of VVI/QC on rumen microbial fermentation. Fermenters were fed 10.9 g/d of dry matter (DM) of a 600:400 forage:concentrate diet. Treatments were control, QC (2.725 mL), VVI leaves 0.080 g) and mixture of QC/VVI (1.362 mL+0.040 g) and were randomly assigned to fermenters within periods. The equivalent of 2.5 g of tannins/kg dietary DM from three sources of tannins was evaluated. All tannin sources decreased CH4 and ammonia concentrations, as well as protozoa and methanogen counts (P<0.001). Vaccinium vitis idaea and QC/VVI tended (P=0.005) to reduce the acetate to propionate ratio. There were no changes in nutrient digestion. Results suggest that these sources of tannins, especially VVI have the potential to reduce rumen CH4 production and ammonia concentration without negative effects on in vitro DM digestibility, total volatile fatty acids and pH. [ABSTRACT FROM AUTHOR]

There is a great interest in reducing the methane emission from ruminants as one possible cause of global warming. The aim of the presented study was to determine the effects of xanthohumol, one of the hop (Humulus lupulus) phytofactors, on methane production, microbial population and basic parameters of ruminal fermentation. The experiment was carried out in a batch culture system. The basic substrate (400 mg) consisting of meadow hay and barley meal (60:40) was supplemented with 0 (Control), 0.1, 0.2 or 1.0 mg of xanthohumol. The basic parameters of rumen fermentation and composition of microbial population were measured after 24 h of incubation. For the first time, the results of this in vitro study have demonstrated that xanthohumol is capable to reduce the methane production, even at the lowest dose applied (0.1 mg/400 mg). The observed reduction in methane production by 12–13% was not accompanied by altering the basic rumen fermentation parameters. However, the practical utility of this supplement needs further investigation under long-term invivo conditions. [ABSTRACT FROM PUBLISHER]

Roe deer ( Capreolus capreolus L.) populations in Poland are characterized by low productivity, which is why their reproductive potential was investigated. The presence of corpora lutea (CL) on the ovaries of females hunted in autumn and winter in the years 2015 and 2016 was assessed. Most animals were post-rut and most often had multiple ovulations. However, in early autumn 2015, 60% of the females had no CL. Therefore, they did not participate in mating at the turn of July/August. Those that did ovulate were found to have one CL. In late autumn, 97% of the females were post-rut, mostly with twin ovulations. This confirmed the occurrence of a late autumn rut. This phenomenon had been suggested in studies but not confirmed. In contrast, almost 100% of roe deer ovulated in summer in 2016. It was hypothesized that the reason for the low mating activity of roe deer in the summer of 2015 was heat stress and limited food resources. The summer was exceptionally hot, with many days in July and August when temperatures exceeded 30 °C. The heat combined with low rainfall led to extreme drought. Meanwhile, July and August are the months of mating activity for roe deer. The late autumn rut allowed the roe deer-a monoestrous species-to limit the consequences of a decrease in mating activity or fertility during the hot summer. Global warming may affect roe deer reproduction, so climatic conditions should be considered in population studies, not only in terms of food availability.