Analysis of genetic variability in the Czech Dachshund population using microsatellite markers

The primary goal of this study was to analyse genetic variation within and among six Dachshund varieties in the Czech Republic using 10 microsatellites from StockMarks^® Paternity Polymerase Chain Reaction (PCR) Typing kit. A total of 632 Dachshunds were sampled – 99 Standard Smooth-haired, 72 Standard Long-haired, 272 Standard Wire-haired, 42 Miniature Smooth-haired, 73 Miniature Long-haired and 74 Miniature Wire-haired. Average observed heterozygosity and polymorphic information content ranged in particular Dachshund varieties between 0.58–0.70 and 0.57–0.64, respectively. Subsequent analysis of the population structure ( F -statistics; Nei's genetic identity) showed that Standard Dachshunds shared allele frequencies most closely with their miniature equivalents, and smooth coat type is closer to Wire-haired coat type than to the Long-haired one. Analysis of molecular variance revealed that 11.81% of the total variance occured among varieties. The value of combined exclusion probability (0.9955) validated usefulness of this panel of microsatellites for parentage verification in all analysed populations. We carried out 234 parentage verifications with 1.28% cases where parentage did not match.     

Magic Modeling of Long-Term Lake Water and Soil Chemistry at Abborrträsket, Northern Sweden

The geochemical model MAGIC has been applied to the Abborrträsket lake catchment in northern Sweden for the period 1843-2000. The two objectives were to 1.) simulate historical biogeochemical fluxes and pools and 2.) test whether the MAGIC model of biogeochemical cycling contradicts the published diatom record of a relatively stable pH (around 6) during the last two centuries in this weakly buffered, acid sensitive lake. Abborrträsket has received elevated sulfur and nitrogen deposition in the second half of the 20th Century and had a large part of its catchment clearcut in 1975. The MAGIC simulation of very small pH decline from 6.1 to 5.9 between 1843 and 1987 was comparable to the published diatom reconstructions of almost stable lake water pH up until the lake was limed in 1988. MAGIC also simulated the modern soil and water chemistry, including lake liming. Thus the diatom indication of stable pH cannot be dismissed as necessarily incorrect.     

Artificial dispersal of endangered epiphytic lichens: a tool for conservation in boreal forest landscapes

Due to increasing fragmentation of the boreal forests of Fennoscandia, a number of epiphytic lichens are now becoming threatened. Since these species typically are limited by a poor ability of dispersal, one possible but largely unexplored strategy for conservation is to disperse lichen material artificially into suitable habitats. Therefore, the objective of this study was to evaluate survival and vitality in lichen fragments from Evernia divaricata (L.) Ach. and Ramalina dilacerata (Hoffm.) Hoffm. after transplantation into three different stand types situated in northern Sweden, using different fragment sizes and modes of transplantation. After one year, survival ranged between 85% and 97.5%, and new growth occurred at all transplantation sites. The study has shown that transplantations of small fragments might constitute a resource-efficient option for establishment of new populations of endangered lichen species, or for enlarging their populations at the present sites of occurrence. In addition, the mode of transplantation was of importance for fragment vitality.     

Morphological and genetic diversity of Momordica cochinchinenesis (Cucurbitaceae) in Vietnam and Thailand

Momordica cochinchinensis (Cucurbitaceae) is native to South East Asia and is important for its nutritional and medicinal properties. There is little information available on morphological and genetic diversity, crop selection and strategic germplasm collection for M. cochinchinensis. In this study, 42 accessions of M. cochinchinensis collected from Vietnam, Thailand and Australia were analysed for diversity study both at a morphological and molecular level. Both morphological and molecular analyses were in agreement and clustered the accessions based on the country of origin. The markers investigated in this study could be used for future applications with samples from unknown origins or for gene tracking for important cultivars. The Momordica accessions were highly polymorphic based on the markers suggesting high genetic diversity. Therefore the results from this study will be important in future strategic germplasm collection, conservation, horticultural development and commercial propagation of M. cochinchinensis.     

Growth performance and meat quality from broiler chickens reared with zeolite and halloysite in feed and straw pellet

The study's aim was to analyze the effects of different levels of halloysite (H) and zeolite (Z) in feed and pellets on the growth and meat quality in chickens; 500 Ross 308 broilers were assigned to five groups (1 g, control; 2–5 g, experimental). In Groups 2–5, different proportions of Z and H in feed (25:75 ratio; 0.5% to 2%) and pellet in kg/m² (2, 0.650H; 3, 0.325H and 0.325Z; 4, 0.650Z; 5, 0.160H and 0.490Z) were used. Body weight was higher than 1 in all experimental groups, and carcass weight was higher, except for Group 2. The feed consumption was lower in Groups 3 and 5 than in Group 4. The breast muscle weight was higher in Group 3 than in the control group. In Groups 2, 3, and 5, the water holding capacity in the breast muscles was better than in Group 4 and in the leg muscles in Groups 3 and 4 than in Groups 1 and 5. Most of the tested characteristics indicate a beneficial effect of aluminosilicates in feed and litter on the growth and quality of meat.     

Relation of porcine myogenin gene PCR/RFLP MspI and reproduction traits of the Czech Large White sows

Reproduction traits are highly important for pigs producers because of effect on economic efficiency. Hence, breeders as well as geneticists try to find the way to improve the reproduction traits. Because the protein coded by the myogenin gene (MYOG) is necessary for regulation of skeletal muscles development during embryogenesis, many authors have studied its influence on the meat traits of pigs. The aim of our study was to determine the effect of myogenin gene on the sows' reproduction traits. There were included 529 litters of 107 Czech Large White sows. Effects on the age of the first conception, service period, insemination index, average birth weight of piglets, average weights of litter at the age of 21 days, total number of born piglets, number of piglets born alive and number of weaned piglets were studied. For studying the influence of myogenin gene on chosen traits we used the mixed linear model procedure REML and in one case general linear model. Significant effects of myogenin gene on the age of first conception, the insemination index and on the litter size were proved.     

Avian response to landscape pattern: The role of species' life histories

We suggest that the life histories of species within communities may differ among geographic locations and that communities from distinct biomes may respond uniquely to a given trajectory of landscape change. This paper presents initial tests relevant to these hypotheses. First, the representation of various life-history guilds in avifaunas from the Eastern Deciduous (EDF) and Pacific Northwest (PNW) forests were compared. Three guilds contained more species in the EDF community (large patch and/or habitat interior guild, small patch and/or edge guild, and fragmentation-sensitive guild). The guild of predators requiring large forest tracts was better represented in the PNW. Next, the relative sensitivity of each community to habitat change was ranked based on the life-history traits of their species. The EDF avifauna had a significantly higher index of sensitivity to both forest fragmentation and to landscape change in general. Among the birds with high scores for sensitivity to landscape change were several species that have received little conservation attention thus far including some associated with open-canopy habitats. Lastly, the validity of using life histories to predict community response to landscape change was supported by the fact that the sensitivity scores for PNW species correlated significantly with independent data on species population trends. While more rigorous analyses are suggested, we conclude that knowledge of life histories is useful for predicting community response to landscape change and that conservation strategies should be uniquely tailored to local communities.     

Direct observation of continuous electric dipole rotation in flux-closure domains in ferroelectric Pb(Zr,Ti)O₃

Low-dimensional ferroelectric structures are a promising basis for the next generation of ultrahigh-density nonvolatile memory devices. Depolarization fields, created by incompletely compensated charges at the surfaces and interfaces, depress the polarization of such structures. Theory suggests that under conditions of uncompensated surface charges, local dipoles can organize in flux-closure structures in thin films and vortex structures in nano-sized ferroelectrics, reducing depolarization fields. However, the continuous rotation of the dipoles required in vortex structures and the behavior of unit cell dipoles in flux-closure structures have never been experimentally established. By aberration-corrected transmission electron microscopy, we obtained experimental evidence for continuous rotation of the dipoles closing the flux of 180° domains in a ferroelectric perovskite thin film.     

Effects of soil moisture manipulations on fine root dynamics in a mature balsam fir (Abies balsamea L. Mill.) forest

We tested the hypothesis that moisture stress affects fine root dynamics during and after the stress. To this end, we investigated the effects of soil moisture on annual and seasonal fine root production and mortality over 4 years in a mature balsam fir (Abies balsamea L. Mill.) stand using a minirhizotron and soil coring. Droughting and irrigating treatments were imposed for 17 weeks during the third year of the study, and post-treatment recovery was measured during the fourth year. Monthly fine root production was often reduced by low soil water content (SWC) during July-September in the pre-treatment years and by imposed drought. Irrigation resulted in higher summer fine root production than in pre-treatment years. In the recovery year, increased fine root production was observed in the previously droughted plots despite low SWC in August and September. Droughting decreased year-end fine root biomass in the treatment year, but biomass returned to pre-treatment levels during the recovery year. Droughting and irrigating did not affect foliage production during the treatment and recovery years. Our results suggest that for balsam fir, establishment and maintenance of a functional balance between foliage and fine root biomass, with respect to moisture supply and demand, can depend on fine root dynamics occurring over more than one growing season. In addition, our findings provided insights into tree growth responses to interannual variation in moisture supply.