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1.
Birds obtained by embryo engineering are used to study embryo development and to produce transgenic birds. As this method of producing birds still generate strong emotions of the public opinion head ornaments, testes and semen characteristics of sex chimera roosters were examined to check whether they differ from chickens obtained by non‐manipulated methods. Measurements of head ornaments, testes and semen were correlated with each other. Semen quality factor (SQF) was calculated, as well as the level of fluctuating asymmetry (FA) of bilateral traits (wattles and testes). Positive correlation was found for comb width and wattle length and comb thickness and sperm concentration. Semen characteristics and FA did not exceed the level encounter in other chicken lines. Results obtained indicate that germline chimeras are similar in appearance of secondary sexual traits, and semen and testes characteristics to chickens produced in non‐manipulated way. 相似文献
2.
Agriculture as a source of phosphorus causing eutrophication in Central and Eastern Europe 总被引:5,自引:0,他引:5
3.
Jan Adamiak Arkadiusz Stępień Ewa Adamiak Dariusz Klimek 《Archives of Agronomy and Soil Science》2013,59(5):435-443
The effect of various fertilization methods on the simplified nutrients balance and changes of soil chemical features in crop rotation was estimated on the basis of 7-year (1994-2000) studies carried out on loess-based, sedimentary-gley, light-clay soil. Different fertilization methods were used: A - mineral fertilization; B - mineral and manure fertilization; C - straw, green manure and mineral fertilization; D - ecological compost and biodynamic preparation fertilization. Particular fertilization methods caused a significant differentiation of the nutrients balance. A positive phosphorus balance was found out in all the fertilization systems. It has been observed that the nitrogen and potassium carry-in with fertilizers was higher than the carry-out with crops in system B and C. A favorable calcium balance was achieved in systems C and D while a favorable magnesium balance - only in the ecologically fertilized systems (D). The changes of soil chemical features were only insignificantly dependent on the nutrient balance. After seven years of research, the contents of humus, phosphorus, potassium, magnesium and calcium increased while the soil reaction decreased in the soil of all the fertilized systems except the ecologically fertilized system. 相似文献
4.
van den Borne JJ Weström BR Kruszewska D Botermans JA Svendsen J Woliński J Pierzynowski SG 《Journal of animal science》2007,85(2):404-412
The objective of this study was to quantify and compare the effects of sow's milk and 2 milk replacer diets (containing clotting or non-clotting protein sources) on exocrine pancreatic secretion, plasma cholecystokinin, and immunoreactive cationic trypsin in pigs. In addition, the relationship between exocrine pancreatic secretion and growth in milk-fed pigs was studied. In a changeover experiment, 9 chronically catheterized pigs of 6.6 +/- 0.19 kg of BW were studied for 3 wk. Pigs were assigned to each of 3 diets. Exocrine pancreatic secretion was measured from the third to the seventh day on each diet. The protein content and trypsin activity of the pancreatic juice were measured. Blood samples were taken at 10 min before and after milk ingestion and were analyzed for cholecystokinin and immunoreactive cationic trypsin. Pancreatic protein and trypsin secretion did not differ between pigs fed sow's milk and those fed milk replacer, but the volume secreted was less for the pigs fed sow's milk (0.75 vs. 1.03 mL x kg(-1) x h(-1); P < 0.01). A postprandial response to milk intake was not observed. The 2 milk replacer diets did not affect exocrine pancreatic secretion differently. The average exocrine pancreatic secretion (volume, 0.94 mL x kg(-1) x h(-1); protein, 4.28 mg x kg(-1) x h(-1); trypsin, 1.65 U x kg(-1) x h(-1)) was intermediate between literature values for suckling and weaned pigs. Plasma cholecystokinin was elevated (approximately 18 pmol x L(-1)) and showed low correlations with the pancreatic secretion traits. Plasma immunoreactive cationic trypsin was not significantly related to any of the pancreatic secretion traits and should therefore not be used as an indicator for exocrine pancreatic function in milk-fed pigs. Exocrine pancreatic secretion varied substantially among individual pigs (protein, 0.22 to 13.98 mg x kg(-1) x h(-1)). Pancreatic protein and trypsin secretion showed a positive, nonlinear relationship with performance traits. It was concluded that neither specific sow's milk ingredients nor the protein source are responsible for a low pancreatic protein secretion in suckling pigs. Exocrine pancreatic secretion was positively correlated with ADG in pigs at an identical milk intake. 相似文献
5.
Lechowski R Bielecki W Sawosz E Krawiec M Kluciński W 《Veterinary research communications》1999,23(1):1-14
Sixty-four Wistar rats were divided into 8 equal groups and kept for 36 days in individual boxes. Three of the groups were given full synthetic diets containing various animal fats: beef tallow, pork fat or fish oil. A control group was fed the diets without the fat. The other four groups were fed the same diets with lecithin supplementation. At the end of experiment, sections taken from the liver were stained with haematoxylin–eosin and Sudan III to indicate fat infiltration. Liver enzyme levels, total bilirubin, albumin and two products of lipd metabolism were measured in serum from all the animals. The addition of lecithin to the diets did not influence the level of enzymes in the serum except in rats fed the diet containing beef tallow. A relationship between the type of diet, lecithin supplementation and the total cholesterol concentration in serum was observed. The concentration of HDL-cholesterol was only influenced by lecithin supplementation and that of triglycerides by the type of fat in the diet. The addition of lecithin to the diet was associated with proliferation of Kupffer cells, and an increased number of binuclear cells. Fatty degeneration of hepatocytes was less pronounced in all groups following lecithin supplementation. Lecithin supplementation of the diet did not elicit any pathological lesions and may be considered as a hepatocyte protector. This favourable effect of lecithin was most marked in the group of rats fed the fish oil. 相似文献
6.
Robert Jankowiak Piotr Bilański Julita Zając Adrianna Jobczyk Stephen J. Taerum 《Forest Pathology》2023,53(4):e12821
In Poland's pine forests, mistletoe (Viscum album subsp. austriacum) abundance has increased over the past 20 years. This mistletoe infestation has decreased the growth and vigour of Scots pine trees. In this study, we surveyed the culturable fungi from healthy and diseased V. album subsp. austriacum leaves from two stands in Poland. In total, 63 distinct species were identified, 99.8% of which belonged to the phylum Ascomycota. The community compositions of fungi in mistletoe leaves were similar in healthy and diseased leaves as Alternaria alternata, Aureobasidium pullulans, Botryosphaeria visci, Fusarium paeoniae and Microsphaeropsis olivacea were consistently found in leaves of all symptom types. The most frequently isolated fungus from asymptomatic leaves was M. olivacea, followed by A. alternata, A. pullulans and Hypoxylon rubiginosum. In comparison, the most frequently isolated fungi from leaves with rusty-brown necrotic spots were (in decreasing order) M. olivacea, B. visci, F. paeoniae and A. alternata, while the most frequently isolated fungi from leaves with black or dark brown spots were M. olivacea, A. alternata, A. pullulans, Epicoccum layuense and F. paeoniae. This study was the first comprehensive report showing that certain fungal species may be pathogens of V. album subsp. austriacum in Poland. This study was also the first report of F. paeoniae, F. juglandicola, Diaporthe vacuae and Heterotruncatella spartii from V. album, and the first report of D. vacuae and H. spartii in Poland. 相似文献
7.
Lucie Beaulieu Jacinthe Thibodeau Claudie Bonnet Piotr Bryl Marie-Elise Carbonneau 《Marine drugs》2013,11(4):975-990
Shellfish waste components contain significant levels of high quality protein and are therefore a potential source for biofunctional high-value peptides. The feasibility of applying a pilot scale enzymatic hydrolysis process to whole Mytilus edulis and, by fractionation, recover hydrolysates presenting a biological activity of interest, was evaluated. Fractions were tested on four immortalized cancerous cell lines: A549, BT549, HCT15 and PC3. The 50 kDa fraction, enriched in peptides, presented anti-proliferative activity with all cell lines and results suggest a bioactive molecule synergy within the fraction. At a protein concentration of 44 µg/mL, the 50 kDa fraction induced a mortality of 90% for PC3, 89% for A549, 85% for HCT15 and of 81% for BT549 cell lines. At the low protein concentration of only 11 µg/mL the 50 kDa fraction still entails a cell mortality of 76% for A549 and 87% for PC3 cell lines. The 50 kDa fraction contains 56% of proteins, 3% of lipids and 6% of minerals on a dry weight basis and the lowest levels detected of taurine and methionine and highest levels of threonine, proline and glycine amino acids. The enzymatic hydrolysis process suggests that Mytilus edulis by-products should be viewed as high-valued products with strong potential as anti-proliferative agent and promising active ingredients in functional foods. 相似文献
8.
Maciej Zalewski Barbara Bis Mazgorzata apiska Piotr Frankiewicz Wojciech Puchalski 《水产资源保护:海洋与淡水生态系统》1998,8(2):287-307
1. The effect of riparian ecotone functional complexity and stream hydraulics on an upland river ecosystem has been analysed. 2. The amount of nutrients retained by bottom sediment was lowest on a sandy substrate (range: 26–104 mg m−2 P-PO4) and highest in wetland bays (range: 558–5368 mg m−2 P-PO4). A stream bed covered by Berula erecta had about three times higher retentive nutrient capacity ( x̄ = 584 mg m−2 day−1) than did a sandy substrate( x̄ = 205 mg m−2 day−1). 3. The amount of allochthonous organic matter (CPOM) deposited on the stream bed decreased with current velocity. The trophic potential of CPOM, measured as total protein, was significantly correlated with the amount of deposited CPOM (r = 0.863; p<0.00001) and depended on stream order. 4. Both invertebrate and fish biomass in the upland river were significantly correlated with calcium/bicarbonate (benthos: r = 0.858; p<0.006; fish: r = 0.918; p<0.001). 5. Fish biomass, diversity and species richness were highest in pools, lower in riffles and lowest in the run/transition zone. 6. Macroinvertebrate biomass was highest at an intermediate riparian ecotone complexity with an adequate supply of organic matter and incident light. Fish biomass followed the same trend, being lowest in heavily shaded areas and in open channels without riparian vegetation (range: 1–4.5 g m−2), but highest in ecotones of intermediate complexity (range: 1.6–92.8 g m−2). The ‘cascading effect’ of invertebrate density depletion, which was inversely related to fish biomass, was observed seasonally. 7. The above results indicate that riparian ecotone structure and the heterogeneity of the stream channel may regulate biodiversity, productivity and nutrient retention in the fluvial corridor. These quantitative data help to create alternative scenarios for sustainable river basin management. © 1998 John Wiley & Sons, Ltd. 相似文献
9.
Małgorzata Szczepanek Edward Wilczewski Jarosław Pobereżny Elżbieta Wszelaczyńska Ireneusz Ochmian 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(4):334-339
In 2009–2011, in Poland (53°13′N, 17°51′E), field experiments were conducted concerning the influence of biostimulants Kelpak SL and Asahi SL on the size grades of yield of carrot cv. ‘Karotan’. Kelpak SL is produced from seaweed Ecklonia maxima; Asahi SL is composed of nitrophenols. Biostimulants were sprayed from fourth-leaf stage of carrot, once, twice or three times in growing period. Seaweed extract was used at total doses of: 0, 2, 3, 4, 5, 6 and 7?l?ha?1, while Asahi SL at 1?l?ha?1. It was found that biostimulants had a favourable effect on total and commercial root yield, but this effect was dependent on the type of preparation, the dose, the time and the number of treatments. The best results in increasing the commercial yield were achieved after a single application of Kelpak SL at doses 2 or 3?l?ha?1 at the fourth-leaf stage (13.1% and 12.4% respectively, compared to the control). Both biostimulants Kelpak SL and Asahi SL positively affected the root size distribution by increasing the yield of medium roots (1.9–3.8?cm in diameter) as well as large roots (3.8–5.0?cm), by 30.5% and 15.8%, respectively. 相似文献
10.
Piotr Hulisz Przemysław Charzyński Andrzej Greinert 《Journal of Soils and Sediments》2018,18(2):358-372