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An analysis chemical composition of 33 samples of five cereal grains harvested in oneyear led to a conclusion that the greatest variations and statistically significant differences (P≤0.01) among cereals existed in their content of crude protein, crude fibre and the following fractions of dietary fibre: NDF,ADF, TDF, IDF and SDF.Analyzed winter wheat and winter rye varieties differ significantly (P≤0.01) from other cereal grains in their content of magnesium, potassium, sodium, phosphorus, manganese, zinc and show a statistically significant difference (P≤0.05) in the content of calcium and copper. The average total content of amino acids was highest in wheat and lowest in winter barley. Lysine was found to be the first amino acid limiting (CS) the quality of protein in all analyzed varieties of cereal grains, with the exception of rye, while tryptophan was found to be such an amino acid for animals (WE). The high content of essential amino acids (EAA) was reflected in EAAI, which forWH ranged from 71% (spring barley) to 84% (winter triticale), and forWE from 51% (winter barley) to 60% (winter triticale).
Food supply is an important determinant of animal movements. In the present study we tested the occurrence of an inverse relationship between daily movements ofMarmosops paulensis (Tate, 1931) and their food supply. This species is a member of the family Didelphidae, occurring in areas of high elevation in the Brazilian Atlantic Forest.M. paulensis moved mostly over the ground, although the understory was also used. Mean daily range ofM. paulensis estimated through spool-and-line device was about 0.40 ha; no differences were noted between body sizes and sexes. As expected, there was an inverse relationship between daily movements and food supply. This relationship resulted from the clumped distribution of fruits, particularlyPiper rather than the sparser distribution of arthropods.
The present study deals with changes in important skull characteristics of the sika deer Cervus nippon Temminck, 1838 in response to changes in food supply. Moderate food shortage results mainly in a linear reduction in skull size, while severe food shortage results in changes in skull shape. In the deer that returned to habitats with sufficient food supply, some skull parameters recovered to, or even exceeded, normal values, whereas other parameters remained stressed resulting in retention or enhancement of skull distortions. Differences in skull parameters among the populations studied were comparable to those between some cervid species, eg, the Siberian roe deer Capreolus pigargus Pallas, 1771 and European roe deer Capreolus capreolus Linnaeus, 1758 and other deer subspecies. In the introduced sika deer populations, skull distortions were apparently caused by interspecific hybridization. Descendants of the escaped deer have not reverted to the normal phenotype, even over several generations, providing a recent case of true evolutionary changes. This occurred by a change in the ratio of different morphotypical groups, probably due to their different responses to food shortage. Thus sufficient food supply may account for changes in a population’s genotypic composition through selection of characteristics that favour passing on genetic material when food is limited.
Population dynamics of ungulates (European bison Bison bonasus, elk Alces alces, red deer Ceruus ela.ph.us, roe deer Capreolus capreolus, wild boar Sus scrofa, non-native fallow deer Dama dama, and cattle) were analysed in the Białowieża Primeval Forest (BPF, 1250 km2), one of the largest remaining tracts of ancient mixed and deciduous forests in the lowlands of Europe. Forty percent of BPF belongs to Poland, and 60% to the Belarus Republic. Polish and Betarussian game departments inventories of ungulate numbers (1946-1993) and archival data on censuses and hunting statistics (1798-1940) are presented. The recorded ranges of densities of native wild ungutates were: European bison 0-1.5 inds/km2, elk 0-0.6, red deer 0-5.4, roe deer 0.6-4.8, and wild boar 0.2-3.8 inds/km2. Fallow deer were introduced in 1890 (maximum density reached in 1914 was 1.2 inds/km2) and were eradicated by 1920. Cattle were traditionally pastured in the Forest, and its grazing impact was heaviest in 1880-1914 (maximum recorded density 6.7 inds/km2). In 1798-1993, the community of wild ungulates consisted of three to six species, with total densities varying from < 2 to 14.4 inds/km2 (65 to 1180 kg of crude biomass per 1 km2). Roe deer, wild boar, and red deer were usually the dominants. However, in 1860-1971, cattle constituted from 15% to 80% by numbers and from 37% to 87% by biomass of all ungulates in Białowieża Forest. Data on population trends within a five-species assemblage of native wild ungu­lates were subject to multiple regression analysis to determine the roles of predation (by wolves Canis lupus and lynxes Lynx lynx), competition, food, weather variables, and humans in shaping population densities and increase rates of ungulates. Growth of the mean annual temperature had positive effect on densities of all ungulates, probably through improving food supply and feeding conditions. Bison and elk were shaped by intra- and interspecific competition for food. Bison numbers have heen significantly limited by humans, due to both uncontrolled exploitation in years of political instability and deliberate culling in years of protection. Red deer and roe deer were primarily shaped by predation from wolves and lynx, respectively. Compe­tition for food influenced red and roe deer when they had erupted after predator extermination. Wild boar was influenced predominantly by food availability, especially the highly variable crops of oak seeds.
The length and body weight at subsequent annuli of four facultative riverine fish species: roach (Rutilus rutilus L.), perch (Perca fluviatilis L.), bream (Abramis brama L.) and pike (Esox lucius L.) living in lakes and rivers were compared on the basis of published data. Pike grew better in lakes (significant differences in length, and some for weight), but the other species in rivers. However, significant differences between medians were observed in all cases only for body length of roach, in many cases for the length of bream, as well as a few for its weight, and no one for perch. Comparable data on relative fecundity in both habitats were available for roach and pike. Pike females produced more eggs in lakes, but roach – in rivers, and the differences were significant.
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