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There was previously no information on nesting, seasonal body mass or the hibernation behaviour of the hedgehog in Ireland. Between 2008 and 2009, hedgehogs were caught, weighed weekly and monitored by radio tracking at a rural Irish site. Day nests were recorded in the active period and hibernacula thereafter. Arable land has been reported to be poorly utilised by hedgehogs in the UK and Denmark. In Ireland, day nests and hibernacula were constructed in the hedgerows of arable land indicating that these areas will be exploited if hedgerow is maintained and highlights the importance of maintaining hedgerows in arable areas. Individual females returned to the same day nest significantly more than males. Over the 2 years, individuals were found to occupy a mean of 1.8 (±0.9; SD) hibernacula (maximum of 3) and they rotated between nests up to four times (mean of 2.5 ± 1.6). When hedgehogs occupied multiple hibernacula, those occupied in mid winter (December and January) were occupied for significantly longer than those occupied at the start (October and November) and end (February and March) of hibernation. Studies in the UK and Denmark have reported on hedgehog hibernation. However, the winter climate in southern Ireland is milder than other areas of Europe and thus it was expected that hibernation characteristics would also differ, i.e. shorter hibernation periods, earlier emergence, lower body mass loss and the ability to survive hibernation at a lower body mass. This proved to be the case with a mean hibernation period (±SE) of 148.9 (±0.5) days, a mean body mass loss of 17.0 (±0.53) %, emergence in March and the ability of late juveniles to survive at a pre-hibernation body mass of 475 g.
W pracy przedstawiono wyniki badań nad próżniowym schładzaniem pieczarek. Schładzano je w komorze próżniowej podłączonej do pompy próżniowej. Podczas schładzania mierzone były następujące parametry: temperatura w komorze, temperatura na powierzchni pieczarki, temperatura w centrum pieczarki, zmiany masy pieczarek oraz ciśnienie w komorze. Na podstawie uzyskanych wyników przedstawiono kinetykę zmian temperatury w centrum i na powierzchni pieczarek podczas badanego procesu. Przeanalizowano zmiany masy schładzanych pieczarek i zmiany ciśnienia w komorze próżniowej. Przedstawiono tabelaryczną zależność ubytku masy od temperatury schładzanych grzybów. Najwyższa szybkość obniżania temperatury wystąpiła w początkowym fazie schładzania i wyniosła 2,7 deg·min-1. W końcowym okresie szybkość schładzania zmalała do 0,75 deg·min-1. Podobnie jak w przypadku zmian temperatury szybkość zmian masy malała wraz z czasem trwania procesu schładzania. Na początku wynosiła 1,8 g·min-1, a w końcowym okresie zmalała do 1,2 g·min-1. Średnia szybkość ubytku masy podczas całego procesu wyniosła 1,4 g·min-1.
Energy balance and body mass changes were studied in non-reproducing adult eastern hedgehogs Erinaceus concolor (Martin, 1838) during an 8-day feeding trial. The amount of energy consumed by the hedgehogs that maintained constant body mass averaged 0.74 kJ x g_1 x day-1. The energy equivalent of body mass loss amounted to 15.12 kJ x g-1, and that of body mass gain was 25.18 kJ energy consumed x g~ . If the energy contents of body mass gained and lost were the same, biomass production efficiency was 72.2%.
We have studied the ability of yeast DNA polymerases to carry out repair of lesions caused by UV irradiation in Saccharomyces cerevisiae. By the analysis of postirradiation relative molecular mass changes in cellular DNA of different DNA polymerases mutant strains, it was established that mutations in DNA polymerases δ and ε showed accumulation of single-strand breaks indicating defective repair. Mutations in other DNA polymerase genes exhibited no defects in DNA repair. Thus, the data obtained suggest that DNA polymerases δ and ε are both necessary for DNA replication and for repair of lesions caused by UV irradiation. The results are discussed in the light of current concepts concerning the specifity of DNA polymerases in DNA repair.
The variation of male (n = 105) and female (n = 107) Southern Grey Shrike body mass has been analyzed in northern Spain during 2000-2002. The annual cycle was divided into autumn (October and November), winter (December to February) and breeding season (March to July), the latter subdivided into egg incubation, small nestlings and large nestlings periods. In order to analyze body mass, the residual index (RI) was used because it corrects body mass related to body size. The mean RI value for males was negative during the whole breeding season and positive during autumn and winter and it did not vary greatly between the periods. In females, the mean RI was definitely greater during egg incubation compared to other periods. The RI value of females was higher than that of males during the egg incubation and large nestlings periods, showing no significant differences in other periods. Female Southern Grey Shrikes (but not males) fitted to the programmed anorexia hypothesis during the breeding season whereas in winter they did not increase their body mass, in clear contrast to what has been put forward in some theoretical models.
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