This paper summarizes the mechanisms behind the patterning of the intra-population abundance distribution of the land snail Vallonia pulchella (Müller, 1774). The molluscs were collected in recultivated soil formed on red-brown clays (Pokrov, Ukraine). Data obtained in this study reveal that V. pulchella population abundance ranges from 1 to 13 individuals per 100 g of soil sample. To obtain estimates of the mean, three models were used: the model of the arithmetic mean, the Poisson model and a log-normal model. The arithmetic mean of the occurrence of this species during the study period was 1.84 individuals/sample. Estimation of the average number of molluscs in one sample calculated using the Poisson model is lower and equals 1.40 individuals/sample. The distribution of the number of individuals in a population was described by the graphics "rank – abundance". The individual sample plot sites with molluscs may be regarded as equivalents of individual species in the community. For the analysis, the following models were used: broken sticks model, niche preemption model, log-normal model, Zipf model, and Zipf-Mandelbrot model. Applying the log-normal distribution gives a lower estimate of the mean density at 1.28 individuals/sample. Median value and mode is estimated at 1.00 individuals/sample. The Zipf-Mandelbrot model was shown as the most adequate to describe distribution of the V. pulchella population within the study area. The Zipf-Mandelbrot model belongs to the family of so-called non-Gaussian distributions. This means that the sample statistics do not possess asymptotic properties and by increasing the sample size, they tend to infinity, and are not close to the values of the general population. Therefore, the average value of the random variable that describes the non-Gaussian distribution has no statistical meaning. From an environmental point of view, this means that within the study area the capacity of the habitat is large, and for some combination of environmental conditions the rapid growth of the abundance of a given species is possible.
Preserving the current diversity of the living material on Earth is fundamental for the survival of future generations . A study was conducted to investigate the genetic diversity of Ukrainian local pig breeds. A total of 350 pigs representing five local pig breeds from Ukraine (Mirgorod – MIR, Poltava Meat – PM, Ukrainian Meat – UM, Ukrainian White Steppe – UWS and Ukrainian Spotted Steppe – USS) and one commercial breed (Duroc, DUR) were sampled. Twelve microsatellite loci (SW24, S0155, SW72, SW951, S0386, S0355, SW240, SW857, S0101, SW936, SW911 and S0228) were selected and belong to the list of microsatellite markers recommended by ISAG. The results indicate that there exists, in general, a high degree of genetic variability within the five Ukrainian local pig breeds. However, the genetic variability in the MIR and PM breeds was significantly lower (mean Na = 2.92–3.92; Ho = 0.382–0.411; FIS = 0.178–0.184) than in the other three Ukrainian local pig breeds – UM, UWS and USS (mean Na = 5.00–8.42; Ho = 0.549–0.668; FIS = 0.027–0.066). Thirty-four private alleles were identified among the six analyzed genetic groups which were distributed between 11 of the 12 loci. A high number of alleles typical for the breed (private alleles) was observed in Duroc pigs – 9 alleles did not occur in Ukrainian local pig breeds. The HWE test showed that all of the polymorphic loci deviated from HWE (P < 0.05) in at least one population. Loci S0355 (5), S0386 (4) and SW24 (4) presented a higher number of populations in imbalance. The mean FST showed that approximately 77.8% of the genetic variation was within-population and 12.2% was across the populations. The five Ukrainian local breeds were classified into two major groups, according to the phylogenetic tree, which was based on standard genetic distance. Overall, we found that 92.6% of the individual pigs were correctly assigned (324 out of 350) to the respective breed of origin, which is likely a consequence of the well-defined breed structure. Probabilities from the allocation test of individuals for the six pig genetic groups were estimated with Structure Harvester. In cluster 1 the highest grouping probabilities were found for the MIR (0.917) and PM (0.750) breeds. Local breeds UM (0.824) and USS (0.772) were grouped in cluster 2. Cluster 3 was related to the local pig breed USW (0.873). Cluster 4 presented high allocation probabilities for the commercial pig breed Duroc (0.924). The obtained results are important for the future conservation of Ukrainian local pig breeds.
The aim of our work is to describe the ecological niche of the land snail Brephulopsis cylindrica (Menke, 1828) in terms of the edaphic properties and properties of the vegetation cover and to show the spatial features of the variation of the habitat preference index within the artificial soil body – technosols (soddy-lithogenic soils on loess-like clays) using the ecological niche factor analysis (ENFA). The research was carried out at the Research Centre of the Dnipro Agrarian and Economic University in Pokrov. Sampling was carried out on a variant of artificial soil (technozems) formed on loess-like clays. The test site where the sampling was conducted consists of 7 transects of 15 samples each. Test points form a regular grid with a mesh size of 3 m. Soil mechanical impedance, aggregate-size distribution, soil electrical conductivity, vegetation physiognomic characteristics, and Didukh phytoindication scales were used as ecogeographic predictors of the mollusc’s ecological niche properties. Phytoindication assessment indicates that the technosol ecological regimes are favourable for sub-mesophytes, hemi-hydrocontrastophiles, neutrophiles, semi-eutrophs. The test for statistical significance showed that an axis of marginality of the ecological niche of B. cylindrica and axes of specialization are significantly different from the random distribution. We found that the ecological niche of the mollusc is determined by both edaphic factors and ecological features of vegetation. The marginality of B. cylindrica ecological niche over the entire period of study is determined mainly by preferences for physiognomic vegetation types, higher values of the continentality and thermality regimes. Often greater content in the soil of aggregates 1–3 mm in size coincides with greater numbers of B. cylindrica individuals. Individuals of this species avoid physiognomic type III and areas with higher soil alkalinity and mineralization detected both by means of the phytoindication approach and soil electrical conductivity data. Ecological niche optima may be presented by integral variables such as marginality and specialization axes and plotted in geographic space. The spatial distribution of the B. cylindrica habitat suitability index (HSI) within the technosols is shown, which makes it possible to predict the optimal conditions for the existence of the species.
All existing data and most of the available materials on Sphyradium doliolum from Ukraine and Moldova are reviewed. The species is reported from 38 localities (some including several sites) on uplands east of the Carpathians, the Dnipro Upland and in the Crimean Mountains. It mostly inhabits the broadleaved forests, but in one locality was found in a forestless rocky meadow steppe at an altitude of ca. 1400 m in the Crimea. Statistical analysis of the morphometric shell characters shows a significant geographical variability between the populations of S. doliolum from the different parts of Ukraine and Moldova. The most prominent morphometric differences were found between the populations from the Crimean Mountains and from all other East European populations combined. An origin of S. doliolum in Eastern Europe is discussed. The results of the morphometric analyses support the hypothesis of the two different origins during the two separate periods for the populations of S. doliolum in the Crimean Mountains and in the East European Plain. These two groups of populations could be representing the two different lineages that perhaps could be of the two different subspecies, but their status requires additional studies involving molecular genetic methods and material from a wider area.
The present study was undertaken to study the relationship between different body measurements and to develop unobservable factors (latent) to define which of these measurements best represent body conformation in the dairy cows. Biometrical observations were recorded on 109 Red Steppe dairy cows randomly selected from State Enterprise «Breeding reproducer «Stepove» (Mykolayiv region, Ukraine) during the 2001–2014. Principal Component Analysis (PCA) was used to account for the maximum portion of variation present in the original set of variables (body traits in cow) with a minimum number of composite variables through STATISTICA software. Most of the pairwise phenotypic correlations among the exterior traits in dairy cows were positive and significant. The Pearson’s correlation coefficients of the body measurements ranged from 0.215 (chest depth – cannon circumference) to 0.889 (height at withers – rump height). In factor solution of the Principal Component Analysis, two (latent) which explained 48.5% of the generalized variance were extracted. The first principal component (PC1) explained general body confirmation and explained 33.5% variation. It was represented by significant positive loading for height at withers, rump height, diagonal length from point of shoulder to pin bone, chest depth, chest circumference etc.). The second principal component (PC2) accounted for an additional 15.0% of the generalized variance and was interpreted as an indicator of body shape (e.g., endomorphic vs. ectomorphic). It was represented by significant negative loadings for height at withers, rump height, diagonal length from point of shoulder to pin bone, but significant positive loadings for chest width, chest depth, chest circumference and cannon circumference. The study also revealed that factors extracted from the present investigation could be used in breeding programs of the dairy cattle.
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