The effect of ionizing radiation on structural changes in the energy nutrients in animal feed

For the purpose of testing the effect of ionizing radiation, feeds for dogs (meat feed mixture VETACAN and loose feed mixture VETAVIT) irradiated by 60Co radioisotope at the dose of 25 kGy/kg were studied for 60 days. It has been found out that the total volume of energetic and non-energetic nutrients is not changed. Qualitative structure, however, displays a significant, on the average 35% disintegration of essential amino acids, decrease of proteins and increase of free ammonic bases. A significant oxidation effect of radiation is exerted on the decomposition of fats with a release of free fatty acids from glycerol bond in a process similar to rancidification (from 13.3-37.10 mg/g in meat mixture, from 103.1-103.04-135.04 mg/g in loose mixture). A certain disintegration of nutrients, only within the limits of significance, occurred also in the saccharide proportion of the loose feed mixture (acidity of water extract 348.8-403.99-436.60 mg/100 g). It has been proved that radiosterilization reliably secures microbiological and mycological sanitation of feeds and causes no sensory changes noticeable by human senses. It follows from the results that ionizing radiation has a pronounced antimicrobial and antimycotic effectiveness. However, it causes significant structural changes of energetic nutrients in the feeds of animal as well as of vegetable origin.     

The effect of feeds treated with ionizing irradiation on biochemical indicators of the nutritional value of energy nutrients

The influence of feedstuffs treated with ionizing radiation on the nutrition of dogs was tested in four groups of animals. Two groups were administered for 90 days a ration, the main part of which (VETACAN meat feed mixture and VETAVIT loose feed mixture) was irradiated with radioisotope Co 60 of the intensity of 25 kGy/kg, in other two groups of dogs the nonirradiated ration was used for the same time period. The control groups of dogs were put together for these two diets. The laboratory examination of irradiated feedstuffs confirmed their complete microbiological and mycological intactness. However, the irradiation brought about a significant 35% degradation of essential amino acids with an increase of ammonia nitrogen, destructive changes in the lipid component of feedstuffs and a partial decomposition of the saccharide part of the VETAVIT feed mixture, expressed by the acidity of water extract. The sensory evaluation of irradiated feedstuffs did not show any perceptible alterations. The haematological examination of the blood of animals, which had been administered irradiated feed rations, demonstrated a significant negative influence on the blood picture. The biochemical examination of the blood serum and plasma revealed that total proteins of experimental dogs dropped and the creatinine level was also significantly decreased. Neither was the level of carbohydrate nutrition nor the energy saturation affected by irradiation. The glucose levels in the blood serum of dogs fluctuated within the range of physiological reference values. The growth of free ammoniacal bases of feedstuffs, evoked by ionizing radiation, conditioned obviously the level of actual pH of blood in dogs as determined in this study. The destruction of lipoid fraction in the feedstuffs induced a decrease in the activity of lipophile retinol and thus the biological value of feeds was impaired. The biochemical examination of ALT, AST and ALP enzyme activity did not show any increased activity of parenchyma, in particular of liver cell. A decisive role of the biological quality of feed ration for utilization of some minerals was demonstrated by a significant decrease of the magnesium level in animals administered irradiated feed rations without any biological supplementation. On the contrary, the potassium, calcium and phosphorus levels did not reflect this dietary difference between the groups.     

Activities of biotransformation enzymes in pheasant (Phasianus colchicus) and their modulation by in vivo administration of mebendazole and flubendazole

Basal activities of certain pheasant hepatic and intestinal biotransformation enzymes and modulation of their activities by anthelmintics flubendazole (FLBZ) and mebendazole (MBZ) were investigated in subcellular fractions that were prepared from liver and small intestine of control and FLBZ or MBZ treated birds. Several oxidation, reduction and conjugation enzyme activities were assessed. In the liver, treatment of pheasants by FLBZ or MBZ caused very slight or no changes in monooxygenase activities and conjugation enzymes. More significative changes were detected in small intestine. Metyrapone and daunorubicin reductase activities were increased by both substances in the liver. This is the first evidence that certain benzimidazoles modulate reductases of carbonyl group. With respect to the relatively slight extent of the changes caused by FLBZ or MBZ we can assume that repeated administration of therapeutic doses of both FLBZ and MBZ has probably no serious influence on pheasant biotransformation enzyme system.     

Effects of Land Use and Wildfires on the Habitat Selection of Great Bustard (Otis tarda l.)—Implications for Species Conservation

Increasing agricultural activities have been shown to affect soil and vegetation changes leading to serious biodiversity declines throughout the world. These effects are amplified in dry grassland areas, where resulting changes in habitat structure affect threatened animals on long temporal scales. Great bustards (Otis tarda) inhabit open landscapes where fire and grazing have been a part of the natural disturbance regime since historical times. Even fire and grazing are hypothesized to be important factors in the lifecycle of the species, studies are still missing on disturbance‐related lekking distribution patterns of great bustards. We analyzed the importance of fires and grazing on the spatial distribution of lekking bustards controlling for habitat types, habitat diversity, distance from roads and social effects. Our standardized dataset spanned 31 years, being one of the largest datasets on bustard lekking. During the 31 years we observed 10 118 individuals at 639 observation points in Hortobágy National Park, East‐Hungary. One of the most important predictors for total number of birds and number of males was the area burnt in previous years. We found that increased habitat diversity had a positive effect on female numbers. Models fit on second‐ and third‐year burn data detected no substantial role of burning on lekking distribution. Our results suggest that introduction of a patch‐burning management system in lekking areas could increase the availability of optimal lek sites for bustards. As an effective management tool, we suggest applying patch‐burning annually in a spatially mosaic structure inside the area occupied by each sub‐population unit. Copyright © 2016 John Wiley & Sons, Ltd.     

Molecular mapping of an aluminum tolerance locus on chromosome 4D of Chinese Spring wheat

Summary The tolerance of aluminum (Al) of disomic substitution lines having the chromosomes of the D genome of Triticum aestivum L. cv. Chinese Spring individually substituted for their homoeologues in T. turgidum L. cv. Langdon was investigated by the hematoxylin method. The disomic substitution lines involving chromosome 4D were more Al tolerant than Langdon. The tolerance was found to be controlled by a single dominant gene, designated Alt2, that is in the proximal region of the long arm of chromosome 4D. The locus was mapped relative to molecular markers utilizing a population of recombinant chromosomes from homoeologous recombination between Chinese Spring chromosome 4D and T. turgidum chromosome 4B. Comparison of the location of Alt2 in this map with a consensus map of chromosomes 4B and 4D based on homologous recombination indicated that Alt2 is in a vicinity of a 4 cM interval delineated by markers Xpsr914 and Xpsr1051. The Alt2 locus is distal to marker Xpsr39 and proximal to XksuC2. The Altw locus is also proximal to the Knal locus on chromosome 4D that controls K⁺/Na⁺ selectivity and salt tolerance. In two lines, Alt 2 and Knal were transferred on a single 4D segment into the long arm of T. turgidum chromosome 4B.     

Throughfall quality and quantity in polluted and damaged ecosystems in Northern Bohemia

The interaction between high concentrations of polluting gases (SO₂ and NO_x) and damaged forest ecosystems was observed by studying throughfall precipitation in the Erzegebirge Mountains, Northern Bohemia. Qualitative and quantitative data on throughfall for the period November 1989–October 1990 are presented. Weighted averages of SO ₄ ^2? and NO ₃ ^? concentrations in the throughfall were 23.05 mg L^?1 and 13.61 mg L^?1 in a beech and 34.41 mg L^?1 and 11.03 mg L^?1 in a spruce forest respectively. Three variables (the molar ratios of K/Na, N_tot/S and N-NO₃/N-NE₄) were used to compare the spruce throughfall quality to that observed in areas with similar however, less damaged spruce stands. Both K/Na and N-NO₃/N-NH₄ ratios clearly decreased with increasing tree damage, the N_tot/S ratio increased. The results suggest that the throughfall in damaged ecosystems of the Erzegebirge region becomes more like a wet precipitation as the tree canopies get sparser and the trees reduce canopy leaching.     

Immediate Impact of the Flood (Bohemia, August 2002) on Selected Soil Characteristics

In August 2002 extreme floods affected Bohemia a part of the Czech Republic, along Vltava and Labe rivers. After the flood had culminated, soil samples of arable and meadow soil (flooded and control-non-flooded) have been collected in the surroundings of the cities of ?eské Budějovice (CB, South Bohemia, the Vltava river, the upper flood stream) and Ústí nad Labem (UL, the Labe river, the lower flood stream). Different parameters of arable soils have been affected more significantly than those of meadow soils. Soil texture e.g. has been shifted from sandy loam to loam (CB) and clay loam (UL). Organic carbon, total phosphorus and nitrogen contents have been increased as well as the content of some hazardous elements such as arsenic. A shift of soil pH from 6.1 to 4.8 has been noticed in CB and an opposite one from 5.1 to 7.1 was measured in UL. Available phosphorus decreased in CB by 56% while a four-fold increase was measured in UL. Chlorinated organic pesticides level was significantly reduced, but that of polycyclic aromatic hydrocarbons (PAH) increased up to the maximum values of legal limits. The UL arable soil also became heavily contaminated by PAH. The CB arable soil demonstrated high microbial activity, while UL arable soil suffered under stress conditions in this respect. The flooded meadow soils became covered with a layer of drifted soil sediment, which retained enhanced content of the PAH's different hazardous elements, and, in addition, the soil aeration was reduced.     

Effect of thinning on anatomical adaptations of Norway spruce needles

Conifers and other trees are constantly adapting to changes in light conditions, water/nutrient supply and temperatures by physiological and morphological modifications of their foliage. However, the relationship between physiological processes and anatomical characteristics of foliage has been little explored in trees. In this study we evaluated needle structure and function in Norway spruce families exposed to different light conditions and transpiration regimes. We compared needle characteristics of sun-exposed and shaded current-year needles in a control plot and a thinned plot with 50% reduction in stand density. Whole-tree transpiration rates remained similar across plots, but increased transpiration of lower branches after thinning implies that sun-exposed needles in the thinned plot were subjected to higher water stress than sun-exposed needles in the control plot. In general, morphological and anatomical needle parameters increased with increasing tree height and light intensity. Needle width, needle cross-section area, needle stele area and needle flatness (the ratio of needle thickness to needle width) differed most between the upper and lower canopy. The parameters that were most sensitive to the altered needle water status of the upper canopy after thinning were needle thickness, needle flatness and percentage of stele area in needle area. These results show that studies comparing needle structure or function between tree species should consider not only tree height and light gradients, but also needle water status. Unaccounted for differences in needle water status may have contributed to the variable relationship between needle structure and irradiance that has been observed among conifers.     

Effect of nitrogen fertilization on yield and nitrogen and water use efficiencies of winter wheat (durum and bread) varieties grown under conditions found in Central Anatolia

In order to evaluate the influence of different N rates on percent N derived from fertilizer (%Ndff) at different growth stages, on yields and the percent N use efficiency (%NUE) values of two winter wheat varieties (durum and bread), field experiments on fallow were carried out at four different locations in Central Anatolia, in the 1991–1992 and 1992–1993 growing seasons. At each site the rates of N (0, 40, 80 and 120?kg N/ha) were applied as ammonium sulphate [(NH₄)₂SO₄] using a Latin Square experimental design with four replicates. The total amounts of N fertilizer were applied once after seedling emergence at all experimental sites. Labelled (¹⁵NH₄)₂SO₄ fertilizer was applied to sub-plots from which %Ndff values were determined at tillering, booting, grain filling, and harvest stages. Yield sub-plots received unlabelled (NH₄)₂SO₄ from which total dry matter (seed and straw) and N yields were determined. Also the %NUE values were calculated by the ¹⁵N and "difference" methods at the harvest stage. Stored soil moisture at 0–90?cm depth, evapotranspiration and water use efficiency values were calculated as well. The results obtained showed that (1) Gerek-79 variety used both the applied N fertilizer and the available soil moisture more efficiently, (2) the percent NUE values obtained overall were generally less than 20 for both varieties and (3) with the ¹⁵N method, less variable %NUE values were obtained in comparison to the difference method.     

Optimizing phosphorus fertilization in an intensive vegetable-rice cropping system

A study was conducted in a sweet pepper-maize-rice cropping system in six farmers fields in Batac, Ilocos Norte, the Philippines, to determine the optimum P fertilizer rate for sweet pepper that will benefit the succeeding crops, maximize system-level productivity and profitability, and reduce the excessive accumulation of P in the soil. Single super phosphate was applied to sweet pepper at rates of 0, 28, 56, 84, 112, and 140 kg P ha^–1 and the succeeding crops were grown without P fertilization. Maize residue was incorporated into the soil at puddling of soil for rice. Phosphorus fertilization at 56 kg P ha^–1 and above had a residual effect on maize and rice. A reduction in the P applied to sweet pepper from 140 to 84 kg P ha^–1 reduced extractable P in the soil at rice harvest from 52 to 29 kg P ha^–1. Phosphorus applied at 111 kg P ha^–1 to sweet pepper was optimum for maximum productivity and economic returns of the sweet pepper-maize-rice cropping system. This rate of P also significantly reduced P accumulation in the soil, thereby reducing the chances of negative effects on soil nutrient balance/availability. The results suggested the need for a cropping systems approach to conserve and effectively use native and fertilizer P in the sweet pepper-rice cropping system.