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1.
1. The effects of 3 commercial enzyme products on the nutritive value of 2 lupin species were investigated with the emphasis on changes in composition of non-starch polysaccharides (NSPs) along the digestive tract. Enzyme A contained primarily cellulase, beta-glucanase and xylanase activities, enzyme B primarily hemicellulase, pentosanase and xylanase activities, and enzyme C primarily hemicellulase, pectinase and beta-glucanase activities. 2. The enzymes were added to semi-purified diets based on sorghum and casein containing 35% whole seed lupins (Lupinus angustifolius cv Gungurru or Lupinus albus cv Kiev mutant). Control diets contained no lupins. 3. Food conversion ratio (FCR), excreta moisture content and apparent metabolisable energy (AME) were affected by lupin species but not by enzyme supplementation. 4. In diets with L. angustifolius, enzyme C significantly increased digesta viscosity and increased the concentration of soluble NSPs in all sections of the intestine. 5. Digestibility of protein and NSPs in the ileum and microbial fermentation in the ileum and caeca were not affected by adding enzymes to diets containing L. angustifolius. 6. Enzyme addition to diets with L. albus did not affect digesta viscosity nor concentration of soluble NSPs but caused a significantly (P<0.05) reduced concentration of insoluble NSP in the ileum. 7. Enzyme addition to L. albus significantly (P<0.05) increased NSP digestibility in the ileum but had no effects on protein digestibility and fermentation in the ileum and caeca.  相似文献   
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Zusammenfassung In der vorliegenden Arbeit wird die Wirkung des Diazinons gegenüber resistenten und normal-sensiblen Stubenfliegen beschrieben. Es handelt sich dabei um Untersuchungsergebnisse, die im Laboratorium und in der Praxis gewonnen wurden. Die im Laboratorium für diese Experimente verwendeten resistenten Stubenfliegen gehören einem Stamm (K1) an, der seit einigen Jahren ununterbrochen mit DDT-Wirksubstanz selektioniert wird und eine Resistenzhöhe erreicht hat, wie sie bei Wildstämmen aus dem In- und Ansland nie festgestellt werden konnte. Auch gegenüber allen anderen gebräuchlichen Insektiziden weisen diese Stubenfliegen eine mehr oder weniger stark erhöhte Widerstandsfähigkeit auf.Die praktischen Untersuchungen mit Präparaten auf der Basis von Diazinon wurden in Dörfern des Kantons Wallis durchgeführt. Eine groß angelegte Erhebung in dieser Gegend zur Abklärung des Resistenzstatus hat ergeben, daß die Stubenfliegen mit keinem der bisher bekannten Insektizide mehr wirksam bekämpft werden können.In Untersuchungen, die in zwei aufeinander folgenden Jahren durchgeführt wurden, konnte nachgewiesen werden, daß Ställe, die mit Diazinon-Spritzpulvern behandelt worden waren, während mehrerer Wochen fliegenfrei blieben. Die Stubenfliegen, die sich zur Zeit der Applikation in den Ställen befanden, wurden innert höchstens 15 Minuten in irreversible Rückenlage gebracht und starben sehr rasch.Weder beim Personal, das die Großversuche durchführte, noch bei der Lebware, die zum Teil bei der Applikation versuchshalber in den Ställen belassen wurde, konnten irgendwelche nachteiligen Folgen festgestellt werden.Diazinon läßt sich in Wohnräumen in den üblichen Formen wie Sprays, Aerosole und Rä uchermittel mit gutem Erfolg gegen Fliegen, Mücken und andere Hausinsekten anwenden. Die Direktwirkung ist nicht so ausgeprägt wie beim Pyrethrum, übertrifft aber die meisten gebräuchlichen Insektizide. Wesentlich ist, daß es bei den resistenten Stubenfliegen keine Reversibilität der Intoxikation gibt, d. h. daß die einmal in Rückenlage gebrachten Tiere sich nicht wieder erholen. Beläge von Sprays auf Basis von Diazinon haben eine mehrwöchige Dauerwirkung.Die Resultate aus Versuchen mit Altlarven resistenter und normalsensibler Stubenfliegen zeigen, daß Diazinon über eine gute larvizide Wirkung verfügt und sich zur Bekämpfung von Stubenfliegenlarven in Gruben, Dunghaufen usw. erfolgreich anwenden läßt.Die bisherigen Erfahrungen mit Diazinon lassen den Schluß zu, daß mit diesem neuen Insektizid resistente Stubenfliegen mit gutem Erfolg bekämpft werden können.Die chemischen und physikalischen Eigenschaften des Diazinons gestatten dessen Anwendung in allen für die Insektenbekämpfung gebräuchlichen Formen.Thiophosphorsäure - [2 - isopropyl - 4 - methyl-pyrimidyl - (6)] diäthylester.Gysin, H.: Un nouveau groupe de substances à activité insecticide.Gasser, R.: Expériences sur la lutte contre les araignées rouges avec de nouveaux acaricides.Grob, H.: Expériences sur la lutte contre les aphides avec de nouvelles substances à base d'uré thanes et d'esters phosphoriques.Vorträge am IIIe Congrès International de Phytopharmacie, Paris, Sept. 1952.  相似文献   
4.
澳大利亚科学家通过观察死亡的蛤蚧卵内壳层和薄膜层,惊喜地对外宣称他们发现了沙门氏菌侵入鸡蛋的方式,但这种方式可能只是加拿大北部的特例,而且蛤蚧与商品化蛋鸡共性又很少,能否直接从蛤蚧卵推测到鸡蛋还有待考证。  相似文献   
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1. The effects of lupin non-starch polysaccharides (NSPs) on apparent metabolisable energy (AME) and composition of digesta from broiler chickens were examined in a dose-response experiment in conjunction with a single combination of 2 commercial enzyme products known from previous studies to partially depolymerise NSPs in diets containing sorghum, casein and lupin kernel. The 7-d experiment was conducted on broiler chickens (24 to 31 d of age) in metabolism cages. 2. The basal diet used in this study contained (in g/kg) sorghum (low tannin) 800, casein 134, celite 20 and vitamins and minerals 46. The inclusion rate for each enzyme product was 0.2 g/kg. Lupin kernel isolate (containing 560 g/kg total NSPs) replaced some of the sorghum and casein. The dose rates of lupin kernel isolate (50, 100 and 150 g/kg) were equivalent to dietary inclusion rates of 80, 160 and 240 g/kg, approximately, of untreated lupin kernel from Lupinus angustifolius cultivar Gungurru. 3. Inclusion of lupin kernel isolate in the diet depressed AME and bird performance, and raised ileal viscosity and excreta moisture, in a dose-dependent manner. 4. A combination of 2 proprietary enzyme products improved dietary AME by 0.3 MJ/kg dry matter. Enzymes reduced excreta moisture when inclusion of lupin kernel isolate was 50 g/kg (equivalent to lupin kernel at 80 g/kg, approximately) but not at higher inclusions. 5. Food enzymes partially depolymerised some insoluble NSPs in lupin kernel isolate, which increased ileal viscosity and soluble NSP content of digesta. 6. It was concluded that development of appropriate exogenous enzyme products could lead to lupin NSPs being used as an energy source for poultry.  相似文献   
6.
Data on 74 trailer loads of finishing pigs (mean BW = 129.0, SEM = 0.63 kg) from wean-to-finish buildings on 2 farms within 1 production system were collected to investigate the effect of amount of floor space on the trailer (0.39 or 0.48 m2/pig) during transport on the incidence of losses (dead and nonambulatory pigs) at the packing plant and to study the relationships between transport conditions and losses. Pigs were loaded using standard commercial procedures for pig handling and transportation. Two designs of flat-deck trailers with 2 decks were used. Floor space treatments were compared in 2 similarly sized compartments on each deck of each trailer type. Differences in floor space were created by varying the number of pigs in each compartment. The incidence of nonambulatory pigs at the farm during loading and at the plant after unloading, average load weight, load number within each day, event times, and temperature and relative humidity in the trailer from loading to unloading were recorded. Of the 12,511 pigs transported, 0.26% were non-ambulatory at the farm, 0.23% were dead on arrival, and 0.85% were nonambulatory at the plant. Increasing transport floor space from 0.39 to 0.48 m2/pig reduced the percentage of total nonambulatory pigs (0.62 vs. 0.27 +/- 0.13%, respectively; P < 0.05), nonambulatory, noninjured pigs (0.52 vs. 0.15 +/- 0.11%, respectively; P < 0.01), and total losses (dead and nonambulatory pigs) at the plant (0.88 vs. 0.36 +/- 0.16%, respectively; P < 0.05) and tended to reduce dead pigs (0.27 vs. 0.08 +/- 0.08%, respectively; P = 0.06). However, transport floor space did not affect the percentage of nonambulatory, injured pigs at the plant. Nonambulatory pigs at the farm were positively correlated with relative humidity during loading and load number within the day (r = 0.46 and 0.25, respectively; P < 0.05). The percentage of total losses at the plant was positively correlated to waiting time at the plant, unloading time, and total time from loading to unloading (r = 0.24, 0.51, and 0.36, respectively; P < 0.05). Average temperature during loading, waiting at the farm, transport, waiting at the plant, unloading, and average pig weight on the trailer were not correlated to losses. These results suggest that floor space per pig on the trailer and transport conditions can affect transport losses.  相似文献   
7.
1. The effects of mannanoligosaccharide (MOS, Bio-Mos, Alltech Inc.) on the growth performance and digestive system, particularly gut microflora, were tested and compared with fructooligosaccharide (FOS, Raftilose P95, Orafti) using 1-d-old birds in an Escherichia coli challenge model. The experiment lasted for 3 weeks and zinc bacitracin (ZnB) was used as a positive control. 2. Dietary MOS had positive effects on body weight gain (BWG) or/and feed conversion efficiency (FCE) of the challenged birds compared to the negative control at the end of weeks 1 and 3. Similar results were obtained for ZnB treatment. In contrast, FOS supplementation improved only the BWG of the challenged birds at 21 d of age. Within the unchallenged birds, a large improvement in BWG was noticed for FOS treatment at the end of the experiment, with the BWG of birds on ZnB and MOS treatments being intermediate. The FCE of the unchallenged birds was not affected by the dietary additives. 3. The addition of MOS reduced the number of mucosa-associated coliforms in the jejunum of the challenged birds on d 7. On d 21, FOS tended to increase the number of jejunal mucosa-associated lactobacilli in both the challenged and unchallenged birds. The number of Clostridium perfringens in the gut lumen was reduced by only ZnB. 4. Dietary MOS reduced the jejunal crypt depth of birds on d 7, regardless of the challenge. The FOS supplement did not affect the gut morphology, however, the concentration of lactic acid in the ileum was increased and, depending on the challenge, the intestinal pH was decreased by FOS at different ages. 5. In conclusion, the effects of MOS or FOS on the composition and activities of gut microflora and mucosal morphology of birds were related to E. coli challenge as well as the age of birds, which may be involved in the observed different growth-improving effects of the tested dietary additives.  相似文献   
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1. A 3 × 2 factorial experimental design was used to investigate the interaction between threonine concentration (0.7, 1.0 and 1.3 of National Research Council (NRC), 1994, recommendations) and manno-oligosaccharides (MOS) supplemented at 0 and 2 g/kg on growth performance in relation to intestinal flow of crude mucins, mucosal development and nutrient utilisation. 2. There was no interaction between MOS and dietary threonine in any performance variable analysed, except for body weight gain during the period to 14 d of age, where body weight gain was significantly lower in birds fed excess threonine in the absence of MOS. Dietary MOS was also observed to significantly increase the body weight gain at deficient and adequate concentrations of threonine. 3. Dietary treatments had no significant effect on either the ileal external muscularis thickness or crypt depth. However, there was a MOS and threonine interaction in the ileal villus to crypt ratio and ileal crude mucin output with both being increased only at the adequate threonine concentration. 4. Dietary MOS tended to interact with threonine to increase the ileal uptake of D-glucose and L-threonine, but the effect was only apparent in birds fed on the deficient or excess threonine diet. There was no significant interaction between MOS and threonine on ileal digestibility of amino acids. Supplementation of MOS or increased dietary threonine significantly increased the apparent and standardised ileal digestibility of threonine. 5. Results from the current study indicate the possible link between the modulating effects of these supplements on intestinal mucosal development and mucin dynamics. This, in turn, may suggest a relatively higher proportion of mature enterocytes and absorptive area, which would be expected to improve the capacity for digestion and mucosal nutrient absorption.  相似文献   
10.
1. A 3 × 2 factorial experimental design was used to investigate the interaction between threonine concentration (0.70, 1.0 and 1.3 of National Research Council (NRC), 1994, recommendations) and manno-oligosaccharides (0 and 2 g/kg) on feed passage rate in relation to intestinal microbial activities and crude mucin turnover. 2. There was no interaction between the effects of manno-oligosaccharides (MOS) and dietary threonine on total tract transit time. However, an interaction between MOS and threonine was apparent where increasing threonine in the absence of MOS led to a reduction in the mean retention time, but a trend in the opposite direction in the presence of MOS. The ileal mean retention time at deficient and adequate concentrations of threonine was also significantly shorter in the presence of MOS. 3. In the jejunum, dietary MOS interacted with threonine to increase the villus-to-crypt ratio with deficient and adequate concentrations of threonine but not with an excess. In the ileum, MOS had no effect on the villus-to-crypt ratio at the deficient and adequate concentrations of threonine but significantly increased the ileal villus-to-crypt ratio with an excess. 4. There were significant interactions between MOS and dietary threonine in their effects on ileal flow of crude mucin, with MOS supplementation increasing mucin concentration and output when threonine was adequate but not when deficient or in excess. 5. Neither MOS nor threonine affected volatile fatty acids and intestinal musculature. No effects of gut microflora or voluntary feed intake on feed passage rate was attributable to dietary threonine or MOS supplementation.  相似文献   
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