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11.
Nine growing barrows were equipped with a T-cannula in the distal ileum and used to determine apparent ileal (AID) and apparent total-tract digestibility (ATTD) coefficients of Ca and P in low-phytate corn, normal corn, soybean meal, and in diets where soybean meal was mixed with low-phytate corn or normal corn. The AID and the standardized ileal digestibility coefficients (SID) of CP and AA also were determined. The animals (initial BW = 29.3 +/- 1 kg) were allotted to a 9 x 9 Latin square with nine diets and nine periods. Three diets contained low-phytate corn, normal corn, and soybean meal as their sole source of CP, AA, Ca, and P, respectively. Three additional diets were identical to these diets except that limestone and monosodium phosphate were added. Two diets contained low-phytate corn or normal corn and soybean meal, limestone, and monosodium phosphate, and the final diet was a N-free diet. The AID and ATTD of Ca were higher (P < 0.05) for low-phytate corn than for normal corn (70.0 and 69.1% vs. 47.4 and 49.6%, respectively). The AID and ATTD for Ca in soybean meal (50.9 and 46.7%, respectively) did not differ from values for normal corn but were lower (P < 0.05) than for low-phytate corn. The AID and ATTD for P from low-phytate corn (56.5 and 54.5%, respectively) were greater (P < 0.05) than from normal corn (28.3 and 28.8%, respectively), whereas soybean meal had intermediate AID and ATTD for P (37.2 and 38.0%, respectively). The AID and ATTD of P increased (P < 0.05) when monosodium phosphate was added to normal corn (44.9 and 49.8%, respectively) and soybean meal (49.6 and 46.2%, respectively), but adding monosodium phosphate to low-phytate corn, did not alter either AID (49.7%) or ATTD (50.7%) of P. No differences between AID and ATTD for Ca or P within the same diet were observed. The AID of Arg, Asp, Gly, Ile, Lys, Phe, Thr, and Val were greater (P < 0.05) in low-phytate corn than in normal corn. The AID of all AA in soybean meal were greater (P < 0.05) than in both types of corn, with the exception of Ala, Cys, Leu, and Met. The SID of Lys, Phe, and Thr were higher (P < 0.05) in low-phytate corn than in normal corn. Because low-phytate corn has a higher digestibility of Ca and P, less inorganic Ca and P need to be supplemented to diets containing low-phytate corn than to those containing normal corn, and P excretion may be decreased when low-phytate corn is used in the diet. 相似文献
12.
Land-cover and structural changes in a western Norwegian cultural landscape since 1865, based on an old cadastral map and a field survey 总被引:4,自引:2,他引:4
Liv Norunn Hamre Stein Tage Domaas Ingvild Austad Knut Rydgren 《Landscape Ecology》2007,22(10):1563-1574
Many studies of land-cover and structural changes in cultural landscapes have used historical maps as a source for information
about past land-cover. All transformations of historical maps onto modern coordinate systems are however burdened with difficulties
when it comes to accuracy. We show that a detailed land survey of the present landscape may enable transformation of an old
cadastral map directly onto the present terrain with very high accuracy. The detailed resulting map enabled us to locate remnants
of semi-natural grasslands and man-made structures with continuity from 1865 and to test hypotheses about relationships between
landscape changes and landscape characteristics. The main land-cover change 1865–2002 was decrease of arable fields, and addition
of three new land-cover classes: horticultural, orchard and abandoned areas. Of the 330 man-made structures present in 1865,
only 58 remained in 2002, while 63 new structures had been built after 1865. We found that semi-natural grasslands with continuity
since 1865 were situated on ground with significantly lower production capacity than mean 1865 production capacity. The man-made
structures with continuity since 1865 were also associated with areas with significantly lower production capacity than the
1865 mean, situated in significantly steeper terrain but not further from the hamlet. Our study illustrates the potential
of digitised and accurately transformed historical cadastral maps combined with detailed field surveys for analysis of land-cover
and structural changes in the cultural landscape. 相似文献
13.
Prof. Dr. W. Stein 《Journal of pest science》1990,63(3):41-46
Zusammenfassung In Laboratoriumsuntersuchungen wurde die Eignung von sechs auch im Winter im Freien vorkommenden Wildfrüchten als Entwicklungs- und Fraßmedium für zehn Vorratsschädlinge getestet.Unbeschädigte Früchte von Stieleiche (Quercus robur), Roteiche (Qu. borealis), Roßkastanie (Aesculus hippocastanum) und Buche (Fagus sylvatica) konnten von keiner der geprüften Käfer- und Mottenarten befallen werden.An oder in beschädigten oder geschälten Früchten von Stieleiche und Buche konnten sich jeweils sieben Vorratsschädlinge entwickeln. Am wenigsten waren Hagebutte und Roteichel als Entwicklungsmedium geeignet.Die Schlüpfrate lag fast immer unter der in der Kontrolle. Nur beiSitophilus granarius schlüpften aus Stieleicheln mehr Imagines als aus Kontrollweizen.Das breiteste Nahrungsspektrum hatten im VersuchOryzaephilus surinamensis, Stegobium paniceum, Ephestia kuehniella undPlodia interpunctella mit je 5 der 6 getesteten Wildfrüchte.Die Buchecker bot allgemein die beste Entwicklungsmöglichkeit. Nur die Arten mit Innenbefall (Sitophilus granarius, S. oryzae undSitotroga cerealella) konnten an ihr keine neue Generation aufbauen.Der Einfluß auf die Entwicklungsdauer war je nach Wildfrucht und Schädling sehr unterschiedlich. Am wenigsten wich sie beiEphestia kuehniella von der normalen Dauer (an einem Gemisch aus Haferflocken, Weizenkleie und Glyzerin) ab.Da Vorratsschädlinge relativ häufig im Freiland gefunden werden können, vor allem in der Nähe von Silos und anderen Vorratslagern, ist nicht auszuschließen, daß Wildfrüchte ihnen eine zeitweise Überlebensmöglichkeit bieten und so, wenn auch sicher relativ selten, als Infestationsquelle dienen können.
Mit 2 Abbildungen und einer Tabelle
Herrn Prof. Dr.J.M. Franz zum 75. Geburtstag gewidmet. 相似文献
Investigations about the development of stored products insects at fruits of indigenous trees and shrubs
In laboratory experiments the suitability of six fruits of indigenous trees and shrubs, which are also available in the field during wintertime, was tested as food and development medium for ten stored products insects.Undamaged fruits of oaks (Quercus robur andQu. borealis), horse chestnuts (Aesculus bippocastanum) and beech (Fagus sylvatica) could not be attacked by any of the tested beetles and moths.Damaged or peeled fruits ofQu. robur andF. sylvatica, however, served as development medium for seven pests. The least fitted substrates were hipberries (Rosa canina) and acorns ofQu. borealis.The number of adults emerging from the wild fruits was normally lower than that from control mediums. An exception was found inSitophilus granarius developing in acorns ofQu. robur. Oryzaephilus surinamensis, Stegobium paniceum, Ephestia kuehniella andPlodia interpunctella had the broadest food spectrum with five fruits each.The beechnut offered the best possibilities for development. Only those insects living inside of seeds (Sitophilus granarius, S. oryzae andSitotroga cerealella) were not able to form a new generation in this fruit.The influence upon the length of the development period was different according to fruit and pest species. The slightest difference, compared with a normal medium (rolled oat, wheat bran and glycerine) was found in the mediterraneum flour moth (E. kuehniella).As stored products insects can be found relatively often in outdoor biotopes, especially in the surrounding of silos or stores, it can not be excluded that fruits of wild plants may offer—at least for a certain period—a possibility for survival. Thus they may act from time to time as a source of infestation.
Mit 2 Abbildungen und einer Tabelle
Herrn Prof. Dr.J.M. Franz zum 75. Geburtstag gewidmet. 相似文献
14.
<正>近期伊利诺伊大学的J.A.Almeida博士、 Hans H.Stein博士以及Carsten Pedersen博士联手展开体重对于标准化回肠蛋白质和氨基酸吸收率的影响试验,结论证明,20 kg以下的仔猪回肠对于粗蛋白和氨基酸的吸收率比20~50 kg的育成猪和50~110 kg的育肥猪低。而且同一猪群的不同猪只也表现出吸收率的差异性。例如,在测定的300只仔猪中粗蛋白和氨基酸的吸收率 相似文献
15.
- 1. The purpose of this report is to determine the concentrations of tributyltin in sediments that would be protective against adverse effects on prey species of salmonids listed under the US Endangered Species Act.
- 2. Two approaches for determining adverse sediment concentrations due to tributyltin (TBT) contamination are presented here. The first is the equilibrium partitioning (EqP) approach, which relies on a sediment‐water partition coefficient and toxicological data for water exposures. The EqP approach utilizes the large water quality database that has been generated over the last two decades for TBT and provides strong evidence for adverse effects at low exposure concentrations.
- 3. The second approach involves determination of a TBT tissue residue that is considered harmful for most species, which is then used to predict the sediment concentration that would likely produce this adverse tissue concentration.
- 4. Both approaches are presented here because they generally support each other but based on the information presented below, and the inherent difficulty in measuring porewater concentrations, the tissue residue approach is the recommended method for determining adverse sediment concentrations.
- 5. Using this analysis, the protective sediment concentration for TBT proposed here is 6000 ng g?1organic carbon. Direct effects are not expected on salmonids at this sediment concentration because of their relatively short residence time in the estuary, general lack of interaction with sediment, and relatively high metabolic capacity. This concentration may ensure adequate abundance of salmonid prey species; however, it may not be low enough for the protection of sensitive benthic species.
16.
An experiment was conducted to evaluate a novel procedure for estimating endogenous losses of P and for measuring the apparent total tract digestibility (ATTD) and true total tract digestibility (TTTD) of P in 5 inorganic P sources fed to growing pigs. The P sources were dicalcium phosphate (DCP), monocalcium phosphate (MCP) with 50% purity (MCP50), MCP with 70% purity (MCP70), MCP with 100% purity (MCP100), and monosodium phosphate (MSP). A gelatin-based, P-free basal diet was formulated and used to estimate endogenous losses of P. Five P-containing diets were formulated by adding 0.20% total P from each of the inorganic P sources to the basal diet. A seventh diet was formulated by adding 0.16% P from MCP70 to the basal diet. All diets were fed to 7 growing pigs in a 7 x 7 Latin square design, and urine and feces were collected during 5 d of each period. The endogenous loss of P was estimated as 139 +/- 18 mg/kg of DMI. The ATTD of P in MSP was greater (P < 0.05) than in DCP, MCP50, and MCP70 (91.9 vs. 81.5, 82.6, and 81.7%, respectively). In MSP, the TTTD of P was 98.2%. This value was greater (P < 0.05) than the TTTD of P in DCP, MCP50, and MCP70 (88.4, 89.5, and 88.6%, respectively). The ATTD and the TTTD for MCP70 were similar in diets formulated to contain 0.16 and 0.20% total P. Results from the current experiment demonstrate that a P-free diet may be used to measure endogenous losses of P in pigs. By adding inorganic P sources to this diet, the ATTD of P can be directly measured and the TTTD of P may be calculated for each source of P. 相似文献
17.
W. Stein 《Journal of pest science》1961,34(6):87-89
Zusammenfassung Um den Einfluß verschiedener Insektizide und Fungizide auf Schlupfwespen der GattungTrichogramma zu prüfen, wurde deren Parasitierungsleistung bei Dauerkontakt mit dem betreffenden Mittel untersucht. Mit unbehandelten Apfelzweigen wurden solche verglichen, die mit den Fungiziden Dithane, Orthozid 50 und Ferbam F 40 bzw. den Insektiziden Ryania, Basudin R, Dipterex, Thiodan oder Metasystox gespritzt waren. Das Alter der Rückstände betrug 0, 24 bzw. 72 Stunden.Alle drei genannten Fungizide reduzierten die Parasitierung in den verschiedenen Varianten erheblich.Das spezifisch gegen Tortriziden wirkende Ryania zeigte praktisch keine toxische Wirkung. Die Anzahl der parasitierten Eier lag entweder gleich hoch wie bei den unbehandelten Kontrollen oder in einem Fall sogar erheblich höher.Die übrigen 4 Insektizide töteten die Schlupfwespen in kurzer Zeit ab, so daß in keinem Fall eine Parasitierung erzielt werden konnte.Noch nicht abgeschlossene Lebensdauerversuche bestätigen die erzielten Ergebnisse.Die Möglichkeiten und Probleme einer gemeinsamen Anwendung vonTrichogramma und Schädlingsbekämpfungsmitteln im Obstbau werden diskutiert.
Dem Leiter des Instiltutes für Biologische Schädlingsbekämpfung, Herrn ORR. Dr. J. Franz bin ich für wertvolle Hinweise und jederzeitige Hilfe dankbar. — Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
Summary To examine the influence of various insecticides and fungicides upon egg-parasites of the genusTrichogramma, their efficiency of parasitization at permanent contact with the concerning pesticide was checked. With untreated applebranches were compared those ones, which were treated with the fungicides Dithane, Orthozid 50 or Ferbam F 40 and the insecticides Ryania, Basudin R, Dipterex, Thiodan or Metasystox resp.All three fungicides reduced the parasitization in the different variations considerably.Ryania, which shows a specific effect against tortricides, had no toxical influence on,Trichogramma.The other four insecticides killed the parasites within a short time, so that in no case a parasitization could be achieved.Investigations concerning the duration of life confirmed the result of the parasitization investigations.The possibilities and problems of a combined application ofTrichogramma and pesticides in apple orchards are discussed.
Dem Leiter des Instiltutes für Biologische Schädlingsbekämpfung, Herrn ORR. Dr. J. Franz bin ich für wertvolle Hinweise und jederzeitige Hilfe dankbar. — Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
18.
The origin of the pair of common carotid arteries in the cat is inadequately described, and there are conflicting accounts in English veterinary anatomy textbooks published in the USA. We found one‐quarter of 40 adult domestic cats dissected had a bicarotid trunk (5 female, 5 male). When present, the bicarotid trunk arose from the brachiocephalic trunk approximately midway between the expected origins of the more frequently independently arising left and right common carotid arteries, and on average, it was 5.6 mm in length. Our findings make the incidence, topographical and measurement information available so that students and veterinarians can be aware of this not insignificant variation in branching of the major arteries, forming a bicarotid trunk, in the cranial mediastinum of domestic cats. 相似文献
19.
20.
Some remarks on carrot breeding (Daucus carota sativus Hoffm.) 总被引:4,自引:0,他引:4
Carrot breeding in the past 150 years has resulted in varieties with high yield, a short growing period, and excellent root colour. Recently, hybrid varieties have demonstrated good uniformity of roots, a quality accepted by most consumers. By contrast, only a few resistant varieties (mainly open-pollinated varieties) are offered by seed companies, most being resistant to Alternaria. Hybrid breeding offers a chance of combining good uniformity and different sources of resistance. Efforts in future breeding should concentrate on the improvement of health and the development of genotypes suitable for cultivation in suboptimal climates and regions, as well as for special applications. 相似文献