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1.
为了合成两种具有抑菌活性的1,4-二氧喹醛酸酯,即1,4-二氧喹喔啉-3-甲基-2-甲酸苯酯和1,4-二氧喹喔啉-3-甲基-2-甲酸肉桂酯,以苯并呋咱为原料,经Beirut反应、酯交换反应,合成了两种喹醛酸酯;1,4-二氧喹喔啉-3-甲基-2-甲酸苯酯合成产率为29.3%,1,4-二氧喹喔啉-3-甲基-2-甲酸肉桂酯合成产率为18.3%。两种1,4-二氧喹醛酸酯对大肠杆菌、金葡萄球菌、青霉菌和枯草杆菌均有明显的抑菌活性。通过测定产物的熔点和光谱分析证明系为所合成的目标产物。 相似文献
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In a three-factorial experiment with 216 piglets of the same age (33 +/- 4 days) but a different weight (weaning weight from 5.5 to 9 kg) a conventional piglet rearing feed containing 20% crude protein (standard), a high-energy diet and a low-protein diet (16% crude protein) were tested. In three weaning weight classes the three diets were fed without or with Bisergon [2-N-(2-hydroxyethyl)-carbamoyl-3-methylquinoxaline-1.4-dioxide] over a period of 21 days. From the 22nd to the 71st day after weaning all the piglets received the standard diet without ergotropic. Among the factors studied the Bisergon supplement had the biggest effect. The additional weight gain varied from 9% in case of heavy piglets fed the high energy diet to 150% in case of light piglets fed the low protein diet. The ergotropic improved feed conversion by 22% and lowered the frequency of gastrointestinal diseases requiring treatment by 28%. At the end of the rearing period the weight of the piglets initially fed with Bisergon (means = 34.6 kg) was significantly higher than that of the control animals (means = 31.6 kg). The weaning weight and the diets influenced the final weight especially in the groups without ergotropic. In this case the piglets fed with the high-energy diet gained 30% more and those fed with the low-protein diet 40% less compared with the standard group. The average live weight gain of the light piglets (weaning weight 6.1 kg) was 30% lower than that of the heavier piglets (weaning weight 8.5 kg). The frequency of treatment against diarrhoea of the heavy piglets was by one third lower than that of the light animals. The piglets fed with the low-protein diet appeared to show a limitation of gastrointestinal diseases, but these animals also had the lowest feed intake. Independent of the Bisergon supplementation the weaning weight clearly influenced the live weight after the 10-week experiment. The initially better development of the animals started with the high-energy diet was compensated. In contrast to this, the piglets weighing 6.1 and 7.2 kg fed with the low-protein diet could not compensate the retarded development in comparison with the piglets fed with the standard or the high-energy diet. This experiment confirms the enormous improvement of the performance and of the health status of weaned piglets caused by the ergotropic Bisergon.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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In 5 experiments 137 fattening bulls received between 0 and 20 mg Mestranol per animal and day. In one experiment a dose of 10 mg/day reduced consumption. The cause of this effect could not be found. In three experiments Mestranol increased weight gain by 4-13%. Feed expenditure was significantly decreased in only one experiment, in which 5-10 mg were given (average of all experiments: 4%). In dependence on the amount of Mestranol the weight of skin, horn and testicles decreased, when only 5-10 mg were given, however, protein retention increased whereas fat retention decreased. When 20 mg Mestranol are given per animal and day, the anabolic effect is missing although the NEFcattle-expenditure per kJ retention including maintenance decreases. This is due to a higher fat retention, which is causally inexplicable. The ergotropic effect of Mestranol depends on its dosage and possibly the nutrients in the ration. 相似文献
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1. A diet with addition to normal barley of malt from transgenic barley expressing a protein engineered, thermotolerant Bacillus (1,3-1,4)-beta-glucanase during germination has previously been demonstrated to provide a broiler chicken weight gain comparable to maize diets. It also reduced dramatically the number of birds with adhering sticky droppings, but did not entirely eliminate sticky droppings. One of the objectives of the broiler chicken trials reported here was to determine if higher concentrations of transgenic malt could alleviate the sticky droppings. 2. Another aim was to investigate the feasibility of using mature transgenic grain containing the thermotolerant (1,3-1,4)-beta-glucanase as feed addition and to compare diets containing transgenic grain to a diet with the recommended amount of a commercial beta-glucanase-based product. 3. Inclusion of 75 or 151 g/kg transgenic malt containing 4.7 or 98 mg/kg thermotolerant (1,3-1,4)-beta-glucanase with 545 or 469 g/kg non-transgenic barley instead of maize yielded a weight gain in Cornish Cross broiler chickens indistinguishable from presently used maize diets. The gene encoding the enzyme is expressed in the aleurone with a barley alpha-amylase gene promoter and the enzyme is synthesised with a signal peptide for secretion into the endosperm of the malting grain. 4. Equal weight gain was achieved, when the feed included 39 g/kg transgenic barley grain [containing 66 mg/kg thermotolerant (1,3-1,4)-beta-glucanase] and 581 g/kg non-transgenic barley instead of maize. In this case, the gene encoding the enzyme has been expressed with the D-hordein gene (Hor3-1) promoter during grain maturation. The enzyme is synthesised as a precursor with a signal peptide for transport through the endoplasmic reticulum and targeted into the storage vacuoles. Deposition of the enzyme in the prolamin storage protein bodies of the endosperm protects it from degradation during the programmed cell death of the endosperm in the final stages of grain maturation and provides extraordinary heat stability. The large amount of highly active (1,3-1,4)-beta-glucanase in the mature grain allowed the reduction of the transgenic grain ingredient to 0.2 g/kg diet, thus making the ingredient comparable to that of the trace minerals added to standard diets. 5. A direct comparison using transgenic grain supplement at the level of 1 g/kg of feed with the standard recommended addition of the commercial enzyme preparation Avizyme 1100 at 1 g/kg yielded equal weight gain, feed consumption and feed efficiency in birds fed a barley-based diet. 6. The production of sticky droppings characteristic of broilers fed on barley diets was avoided with all 9 experimental diets and reduced to the level observed with a standard maize diet by supplementation with transgenic barley. 7. The excellent growth and normal survival of the 400 broilers tested on barley diets supplemented with transgenic grain or malt showed the grain and malt not to be toxic. 8. The barley feed with added transgenic grain or malt containing thermotolerant (1,3-1,4)-beta-glucanase provides an environmentally friendly alternative to enzyme additives, as it uses photosynthetic energy for production of the enzyme in the grain and thus avoids use of non-renewable energy for fermentation. The deposition of the enzyme in the protein bodies of the grain in the field makes coating procedures for stabilisation of enzyme activity superfluous. 9. Barley feed with the small amount of transgenic grain as additive to normal barley provides an alternative for broiler feed in areas where grain maize cannot be grown for climatic reasons or because of unsuitable soil and thus has to be imported. 相似文献
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This new research discovery indicates that the energy requirement of horses for maintenance and performance must take into consideration their body condition, as well as the environmental temperature. Performance horses, especially in the hot months, should not be too fleshy. During the hotter and more humid times of the year, it is also advisable for performance to be accomplished in the cooler parts of the day especially early morning or late evening. This is more critical with horses that are in a fleshy condition.Horses in fleshy condition will consume more feed. This may help explain why halter horses with considerable body condition eat large amounts of grain. They need more energy to maintain their body weight and have an extra maintenance requirement for being “fleshy.”Adding fat (10%) to the ration of performance horses will decrease feed intake and therefore feed cost. It will be metabolically beneficial to all horses in hot/humid weather but especially to those that may be over-conditioned. 相似文献
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D. Droumev 《Veterinary research communications》1983,7(1):85-99
Some antibiotics and synthetic chemotherapeutics of quinoxaline and nitrofuran groups have a practical value among the agents stimulating weight gain and feeding efficiency of farm animals commonly referred to as nutritive, ergotropic agents or growth promoters. In order to avoid undersirable results for human beings they should not be applied for therapeutic purposes; they should not bring about any resistance in microorganisms and should not carry the risk of lowering the therapeutic activity of antibiotics and chemotherapeutics; they should not be absorbed from the alimentary tract and should be rapidly eliminated from the animal body; they should not cause allergic reactions in animals or humans and should act chiefly against Gram-positive microorganisms. The following nutritive antibiotics are described: flavophospholipol (producing an ergotropic effect not only in young animals but also in ruminants; having an antiplasmidic action and restoring the sensitivity of some resistant bacteria towards antibiotics), avoparcin (also active in ruminants), virginiamycin, zinc bacitracin and bacitracin methylene disalicylate, grisin (having a broad spectrum of antibacterial activity, an antimycotic action; stimulating fertilisation and phagocytosis), vitamycin-A (active at low concentrations of retinol in the feed), lambdamycin, noziheptide, efrotomycin. Due consideration is given to some chemotherapeutics such as nitrovin, carbadox (having a broad spectrum an antimicrobial action; giving residues for a long period in the body of pigs), olaquindox (with a broad spectrum, active more on Gram-negative microorganisms, applied mostly as a therapeutic agent), cyadox (with broad spectrum and lower toxicity). Polyether (ionophorous) antibiotics with an anticoccidial action and with an ergotropic activity in ruminants (increasing the molar percent of propionic acid and decreasing that of acetic and butyric acid; suppressing the production of carbon dioxide and methane; enhancing the blood sugar content) are mentioned: monensin sodium, lasalocid sodium, salinomycin sodium, lonomycin and narazin. 相似文献
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Lactating Black-Pied (DSR) cows were used to study, over a period of 100 days, the influence of different basal ration types (I-treated wheat straw pellets, low-fibre; II- monodiet pellets containing 48% of wheat straw; III = conventional rations based on fresh forage and arable root crops) on the molar fermentation pattern and the daily rate of VFA production and some milk yield criteria. Ration types I and II results in almost equal fermentation patterns of the VFA; as against the conventional ration types (III) a significantly higher molar acetate propertion as well as a highly significantly decreased molar proportion of iso-acids were found. The daily rated of VFA production relativated to energy intake were as follows (in the order of the ration types mentioned): 4.9, 4.2 and 5.0, and 3.3, 2.5 and 3.3 moles per 1,000 anergetic feed equivalents (cattle) after 30 and 100 days of feeding, respectively. In both trials, only about 80% of the relative VFA production of the straw pellet-concentrate (I) and conventional (III) ration types were found when feeding fully pelleted diets (II). On account of the relatively wide variation of the experimental results no statistically secured findings were obtained as to the milk yield criteria, but ration type II produced some 200 and 300 kg milk less thant ration types I and III, respectively, during the 100-day experimental period. 相似文献
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An experiment with five litter-mate barrows showed that severe reduction in feed intake and growth rate accompanied the inclusion of either 1.0 or 2.0% ergot in the ration. Levels of 0.10 and 0.05% ergot allowed moderate feed intake and weight gain but not equal to the pig fed the ergot-free ration. A subsequent experiment involving five lots of four litter-mate barrows each, indicated the possibility of reduced feed intake and growth performance by growing-finishing pigs fed rations containing 0.05 — 0.10% ergot. This was substantiated by a N-balance experiment in which control pigs retained 1.54 gm more N daily than pigs fed 0.10% ergot. The total alkaloid content of the ergot used in these experiments was 0.292%; the predominant alkaloid (71%) being ergocristine. 相似文献
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Samples of blood, urine and milk were examined in 94 clinically healthy cows of 10 herds. The average milk samples and the feed ration used in these herds were also examined. The determination of urea concentration and milk acidity was evaluated as to its suitability for the assessment of the protein-glycide ratio and acid-base activity of feed ration. The determination of urea content in an average milk sample was found to be an expeditious procedure. The results of this examination can be used for the evaluation of the protein supply to cows with the same reliability as the determination of serum urea. The passage of urea from serum to milk was proportional. The correlation coefficient for the relation of both parameters was statistically highly significant (r = 0.940). According to the calculated equation of regression line (f2 = 0.734 + 0.669 X f1), the values from 2.94 to 4.10 mmol/l are approximately adequate to the reference range of serum urea from 3.30 to 5.00 mmol/l in milk used in Czechoslovakia. The acidity of milk was found to have a low sensitivity for being used with success for the determination of the acid-base activity of feed ration. The examination of the net acid-base urinary output cannot be replaced by the determination of milk acidity. 相似文献
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Three experiments with five wether each were carried out in order to investigate the influence of various levels of flavomycin (0, 5 and 10 mg per animal and day) on apparent digestibility of artificially dried grass. A short time individual feeding experiment (42 days) with 9 bulls and a long term individual feeding experiment (225 days) with 52 heifers were conducted. Animals consumed 0 or 30 mg flavomycin per day. Parameters of rumen fermentation were investigated. Feed intake and weight gain were measured in the experiment with heifers. Flavomycin did not significantly influence the apparent digestibility of organic matter and crude nutrients as well as parameters of rumen fermentation. Flavomycin did not influence dry matter intake, but increased significantly weight gain (49 g per animal and day, 10.5%) and reduced feed and energy required per kg weight gain (10.6%) in heifers. The reasons of ergotropic effects of flavomycin are mostly unknown at present. 相似文献
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In farm production conditions two comparative trials lasting 58 and 128 days were carried out. Acidogenic exposure to acids of silage juices, silage and haylage (lactic acid, acetic and butyric acids) in feed ration ranged from 0.33 to 2.85 mol per 100 kg live weight. It was proved that it was possible to include 9 to 10 litres of silage juices in feed ration under the condition that the total daily intake would not exceed 1.94 mol of acids per 100 kg live weight. This supplement of silage juices increased milk production. Higher amount of acid (2.65 and 2.85 mol) resulted in acidogenic and ketogenic type of silage juice enriched feed ration, which caused a more rapid decrease of lactation curve in dairy cows fed this feed ration than in those in the control group. 相似文献
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In three experiments with fattening pigs the supplementation of a ration with 8% rapeseed oilmeal (RSO) with 1 mg J/kg resulted in an increased weight gain per day of 31, 94 and 87%. On the other hand, only 83, 76 and 84% of the weight gain of the soybean oilmeal control groups were achieved. The additional supply with 250 mg Cu (experiments II and III) increased the weight gain to 84 and 96% in comparison to the unsupplemented control groups. The combination of J + Cu + Zn lead to the same performance as that of J + Cu (experiment III). In the RSO groups without J-supplement changes in body proportions and parakeratosis could be observed after approximately equal to 7 weeks. After the sole supplementation of Cu these symptoms occurred approximately equal to 4 weeks later. In vitro, the supplementation of RSO with a CuSO4 solution resulted in a decrease of vinylthiooxazolidon and isothiocyanate in line with the CuSO4-concentration. 0.2 mg J/kg feed (experiment III) resulted in the same fattening performance as the supplementation of the ration with 1 mg J and outwardly visible deficiency symptoms. The results show that Cu, depending on its quota, results in a decrease of goitrogenics in the feed and that J and Cu supplementation to rations with rapeseed oilmeal have an additive effect and that parakeratosis can be prevented by J-supplementation. 相似文献
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The effect of the addition of zeolite to pig feed ration was studied in the cage rearing system under production conditions. Zeolite was mixed in the COS I and COS II feed mixtures directly in the feed plant, the mixing ratio being 100 kg feed mixture + 5 kg zeolite. The feed mixture was administered in granular form ad libitum. The test group had 648 weanlings and the control group 674 weanlings; the piglets, kept in two-story cages in four sections, were arranged so that the test group could be a mirror-like reflection of the control group. The trial lasted 45 days. The piglets given the fortified feed ration had daily weight gains higher by 0.017 kg and feed consumption lower by 0.234 kg per 1 kg of gain, as compared with the control animals. The costs of the feed ration required for producing a kilogram of gain were 8.55 Cz. crowns in the zeolite group and 9.422 crowns in the control group. 相似文献
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C M Czarnecki 《Avian diseases》1991,35(4):930-936
Ten turkey poults each were placed in one of four groups: control, thyroxine (T4), furazolidone (FZ), and FZ + T4. Thyroxine (T4), at a concentration of 1 ppm, was included in the ration of poults fed T4 and FZ + T4, and furazolidone (FZ), at a concentration of 700 ppm, was included in the ration of poults fed FZ and FZ + T4 from 2 to 5 weeks of age. Levels of plasma T4 decreased significantly (P less than or equal to 0.05) between 2 and 5 weeks in control and FZ poults. At 5 weeks, plasma T4 levels were significantly (P less than or equal to 0.05) lower in FZ poults than in control poults and significantly (P less than or equal to 0.05) lower in the FZ + T4 poults than in the T4 poults. Exogenous administration of T4 had no effect on development of the round heart syndrome or on body weight, but significantly increased feed consumption in FZ-fed poults during weeks 4 (P less than or equal to 0.05) and 5 (P less than or equal to 0.01). Inclusion of T4 in the ration increased plasma levels of the hormone 12x in both T4 and FZ + T4 poults and significantly (P less than or equal to 0.05) increased myocardial glycogen content in T4 poults but not in FZ + T4 poults. 相似文献
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Total metabolism experiments with a basic ration were carried out over two measuring periods and with a basic ration plus supplements of raw sugar beets, steamed sugar beets, dried sugar beet pulp, sucrose and apple pectin resp. with 4 pigs per test group and 4 test groups (LW 40-135 kg). Live weight gain was approximately equal after the feeding of raw and steamed sugar beets. It amounted to 650 g/animal and day in the first experimental period and to 715 g in the second. After feeding dried sugar beet pulp as supplement the corresponding weight gain was 525 and 565 g/animal and day. In the course of the ontogenetic development up to a live weight of about 70 kg an increase of digestibility could be observed. Adaptation cannot be excluded. This question will be pursued in the following experiments, so that consequences for energetic feed evaluation have to be postponed. For both raw and steamed sugar beets the digestibility of the organic matter was 88%, of NFE 95% and of water soluble carbohydrates 95%. 相似文献
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The two possible pathways contaminating milk and milk products with mycotoxins are either the secretory or post-secretory route. The latter is of only little importance due to cooling conditions in production and storage. A secretory contamination can only occur with such mycotoxins, which undergo no complete degradation through their passage into the milk. From the mycotoxins, present in cow's feed; virtually only aflatoxin B1 yields a milkborne metabolite, the aflatoxin M1. The carry over rate is low (2 +/- 1%), but can be enhanced by polyhalogenated biphenyls, also present in the forage. Under normal conditions, however, this enhancement will not be measurable due to low equimolar concentrations of both reactants. The aflatoxin M1 content in herd's bulk milk depends exclusively on the content of the precursor aflatoxin B1 in the ration of the cow and is with less than 10 ng/kg fairly low at present in the Federal Republic of Germany. A careful supervision of the imported feed ingredients for mixed feed, however, will ensure to keep those batches out of dairy cow feeding which exceed a certain level of aflatoxin. The legal threshold is 10 micrograms/kg, being even too high to ensure a milk containing less than 10 ng/kg under high energy feeding conditions. The discussed thresholds for aflatoxin M1 in milk are 50 and 10 ng/kg resp., the latter value is scheduled for milk used in infant nutrition. To keep this low concentration the intake of aflatoxin B1 must be less than 2 micrograms/kg of the daily ration. 相似文献
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T. F. Kröber M. Kreuzer M. Senn W. Langhans F. Sutter 《Journal of animal physiology and animal nutrition》2000,84(5):148-164
A 5‐week experiment with 24 multiparous early lactating Brown Swiss cows was conducted to investigate the effects of supplementary rumen‐protected methionine in conjunction with dietary protein reduction on metabolism and performance after 1 week of control measurement. Three rations containing 175, 150 and 125 g of crude protein/kg feed dry matter were supplemented with methionine. The fourth ration, also only containing 125 g of crude protein/kg dry matter, remained unsupplemented. The four treatment groups had a similar metabolic supply of other essential amino acids, protein and energy, as calculated by various approaches. The two low protein rations were, however, slightly deficient in ruminally degraded protein. Treatment effects remained low on feed intake, forage meal pattern, milk yield and fat as well as lactose content. In contrast, the content and yield of milk protein significantly declined only in the unsupplemented low protein ration relative to the initial value. Compared with this ration, the decline in milk protein yield was clearly delayed in the supplemented low protein ration. Blood plasma methionine tended to be reduced without supplementation and to be increased with additional methionine. Supplementation of methionine reduced other plasma amino acids. Plasma insulin, glucose, lactate, ketone bodies and aspartate amino transferase activity indicated a certain liver stress and a somewhat elevated energy requirement with high and particularly with low protein content (when unsupplemented). Methionine improved metabolic protein utilization, followed by the lowest plasma, urine and milk urea levels in the supplemented low protein diet. In conclusion, no major adverse effects were assessed under the conditions tested. Supplementation of methionine may nevertheless be useful in rations with particularly low protein content fed to early lactating cows in order to prevent negative long‐term effects which were only visible here as trends. 相似文献
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Influence of supplementary fibrolytic enzymes on the fermentation of corn and grass silages by mixed ruminal microorganisms in vitro 总被引：4，自引：0，他引：4
Wallace RJ Wallace SJ McKain N Nsereko VL Hartnell GF 《Journal of animal science》2001,79(7):1905-1916
This study was done to determine the effectiveness of supplementary enzymes at increasing the fiber digestion by ruminal microorganisms and to assess whether enzyme activity limits the rate of fiber digestion in ruminal digesta. In vitro comparisons of enzyme activities in two feed enzyme preparations (A and B) with enzyme activities extracted from ruminal fluid indicated that the addition of fibrolytic enzymes at the application rates recommended by the manufacturers would not be expected to increase significantly glycanase and polysaccharidase activities in ruminal fluid. Preparations A and B both increased (P < 0.001) the rate of gas production from freeze-dried corn and grass silages in in vitro incubations with ruminal fluid, but only at concentrations much higher than recommended application rates. Autoclaved controls had little or no effect. Ultrafiltration of enzyme B indicated that most stimulation was due to components >100 kDa, which is consistent with the cause of the stimulation being enzyme activity. Fibrolytic enzymes from other sources were also able to stimulate gas production: increased rates of gas production were observed in seven out of eight combinations of "cellulase" and corn or grass silage (P < 0.05). The comparison of glycanase and polysaccharidase activities with gas-stimulatory activity in the different enzyme preparations indicated that the highest correlation was between increased gas production and enzyme activity against microgranular cellulose (P < 0.05). In a wider range of fibrolytic enzyme preparations, those with endo-(beta-1,4)- or exo-(beta-1,4)-xylanase activity equal to that of preparation A did not produce similar increased rates of fermentation of corn silage when glucanase activity was low (P > 0.05). In contrast, preparations with glucanase activity similar to enzyme A gave at least as great (P < 0.05) an improvement in gas production than enzyme A, irrespective of xylanase activity. It was concluded that enzyme activity, probably a type of endo-(beta-1,4)-glucanase activity, limits the rate of fermentation of corn and grass silage in the rumen. Enzyme supplements of the type used in these experiments are unlikely to possess sufficient activity to overcome this limitation by direct application to ruminal digesta, implying that treatment of the ration prefeeding will be key to harnessing the potential of exogenous fibrolytic enzymes in ruminant nutrition. 相似文献