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61.
After 15N-labelling over 7 days male albino rats (92-95 g live weight) received either a wheat or whole egg diet (10 animals each) for 4 days. On the following day of the experiment 5 animals each continued to receive their diets as their morning meal (group 1 whole egg, group 3 wheat) and 5 animals each after the previous feeding of a wheat diet received a 2.9 g whole egg diet (group 2) and after the previous feeding of a whole egg diet a 2.85 g wheat diet (group 4) resp. This morning meal was supplemented with chromium(III)oxide. The rats consumed their meals within 20 minutes. The animals were killed 3.5 hours after the beginning of feed intake. At that time the following relative amounts (in % of the intake) could be detected in the stomach in the sequence of groups 1 to 4: Cr2O3 = 22.5; 26.5; 57.5 and 64.2; dry matter = 25.4; 22.1; 43.2 and 38.5. The better agreement between the whole egg diet and Cr2O3 can be explained with the hydrophobic qualities of Cr2O3 and the small disposition of the Cr2O3 to decompose in combination with the whole egg diet. In the first third of the small intestines less than 1% of the intake of Cr2O3 and a maximum of 3.5% of the DM could be detected. Between 20 and 36% of the Cr2O3 and between 15 and 20% of the dry matter intake were ascertained in the small intestines as a whole; in the large intestines the values were 12-20% of the Cr2O3 and 16-23% of the DM. Endogenous 15N-secretion could be ascertained in all parts of the digestive tract. According to the method suggested by U. Bergner and H. Bergner (1982), protein digestibility in the last third of the small intestines was calculated as follows: (formula; see text) The following ileal digestibility values were calculated for crude protein: whole egg = 95.6%; whole egg (wheat previously) = 95.5%; wheat = 94.1%; wheat (whole egg previously) = 85.1%. It is a precondition for the application of this method that at the time of killing representative quotas of the diet sample to be tested can be detected both in the stomach and the large intestine so that the decrease of 15N-labelling in the ileum is actually caused by the test protein. 相似文献
62.
Małgorzata Ksia̧żek Adam Woźny Fortunat Młodzianowski 《Forest Ecology and Management》1984,8(2):95-105
In tissue cultures of Populus maximowiczii Henry, Pb(NO3)2 had a restraining effect on fresh weight increase and anthocyanin content. In ultrastructural research Pb deposits of various size were mainly present in the intercellular spaces, cell walls (mainly in the region of the middle lamella), in the paramural bodies and in the vacuoles. Small deposits of this metal were also observed in the endoplasmic reticulum (ER), dictyosomes and dictyosome derivated vesicles. 相似文献
63.
Jatropha curcas seed was fed to six calves at doses of 2.5, 1 and 0.25 g/kg once and to two other calves at 0.025 g/kg up to 14 days. The onset of toxic manifestations in the six calves was rapid and death occurred within 19 hours of administration. The two calves that received daily the lowest dose of J. curcas showed signs of poisoning and died within 10 to 14 days. The clinical signs of diarrhoea, dyspnoea, dehydration and loss of condition were well correlated with the pathological findings. There was an increase in aspartate aminotransferase, ammonia and potassium and a decrease in total protein and calcium in the serum of jatropha-poisoned calves. 相似文献
64.
Kile JC Panella NA Komar N Chow CC MacNeil A Robbins B Bunning ML 《Journal of the American Veterinary Medical Association》2005,226(8):1349-1353
OBJECTIVE: To estimate West Nile virus (WNV) infection rates, assess environmental variables that correlated with seropositivity in dogs and cats, and assess whether pets should be considered as possible sentinels for WNV and therefore of potential human exposure. DESIGN: Cross-sectional serosurvey. ANIMALS: 442 dogs and 138 cats. PROCEDURE: Serum samples were screened for seropositivity against WNV by use of the plaque reduction neutralization test. RESULTS: 116 (26%) dogs and 13 (9%) cats yielded positive results. The odds of seropositivity against WNV for outdoor-only family dogs were almost 19 times as great as those for indoor-only family dogs and almost twice as great for stray dogs as for family dogs. Family dogs not receiving heartworm medication were 2.5 times as likely to yield positive results for antibodies against WNV as family dogs receiving heartworm medication. CONCLUSIONS AND CLINICAL RELEVANCE: Seropositivity was greater for outdoor family dogs than for indoor family dogs. Further investigation of the potential use of stray dogs as sentinel indicators for WNV infection and the potential risk of human exposure is warranted. 相似文献
65.
66.
Driks A 《Phytopathology》2004,94(11):1249-1251
ABSTRACT Bacilli, which are abundant in the soil, form highly resistant dormant cell types, called spores, in response to starvation. The spore is organized into a series of concentrically arranged structures, each of which contribute in a different way to resistance against environmental stress. In certain bacteria, including Bacillus subtilis, the outermost of these structures is a multilayered protein shell, called the coat. The coat is both an armor plating and, almost certainly, possesses enzymatic activities, allowing it to have active roles as well. Assembly of the proteins comprising the coat is carefully controlled during spore assembly, resulting in a distinct pattern of layers, seen in cross section, and a discreet pattern of ridges on the surface. Although our understanding of spore coat composition and assembly is deepening, we still know little about the roles of the coat in interactions between spores and other organisms, particularly in the soil. Critical future directions for spore coat research include continued identification of the proteins that comprise the coat surface, characterization of the global chemical characteristics of this surface, and elucidation of how these features impact on other organisms in the soil. 相似文献
67.
68.
Adam B 《DTW. Deutsche tier?rztliche Wochenschrift》2004,111(3):108-10, 112
Every year numerous downstream migrating fish are lethally injured by hydro power plants and inlet works. Especially the katadromous Eel (Anguilla anguilla) and anadromous species like Atlantic Salmon (Salmo salar), which have to migrate downstream into the ocean for closing their life cycle, are highly endangered. Due to their specific migratory behavioral pattern, size and morphology conventional protection techniques, like screens do not properly keep them out from getting into the power plant intakes. Despite of the relevance of this problem for ecology and fishing, there are no protection and downstream migration facilities in Europe available, which can efficiently avoid the damage of all species and sizes of downstream migrating fish. Nevertheless according to protect the fish populations it's necessary to use consequently fish protection and downstream migration facilities, i.e. mechanical barrieres or alternative techniques like early warning systems as a prerequisit for a fish-friendly operational management of hydro power plants. 相似文献
69.
Adam AA Takahashi Y Katagiri S Nagano M 《The Japanese journal of veterinary research》2004,52(2):77-84
Effects of oxygen (O2) tension in the gas atmosphere during in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) on the efficiency of in vitro production of mouse embryos were examined. Mouse oocytes recovered from large antral follicles were subjected to IVM in Waymouth medium for 15, 16 and 17 hr under 5 or 20% O2 and then subjected to IVF and IVC under 5 or 20% O2 tension. Lowering the O2 tension in the gas atmosphere for IVM from 20 to 5% improved the cleavage rate after IVF when the oocytes were subjected to IVM for 15 hr; however, no improvement in the cleavage rate was observed when the culture period for IVM was extended to 16 and 17 hr. Lowering the O2 tension to 5% for IVM and IVC improved the development of the cleaved oocytes to the blastocyst stage, regardless of the culture period for IVM. However, the O2 tension for IVF had no remarkable effect on the subsequent embryonic development. These results demonstrate that 5% O2 is superior to 20% O2 for IVM and IVC, and suggest that 20% O2 for IVM may delay oocyte maturation and/or the acquisition of fertilizability and impair the developmental competence of oocytes. 相似文献
70.
Adam M Contzen M Horlacher S Rau J 《Berliner und Münchener tier?rztliche Wochenschrift》2006,119(5-6):209-215
The identification of thermotolerant campylobacters in official food control in the state of Baden-Wuerttemberg has been traditionally performed using the cultural procedure as described in the ISO-Norm 10272:1995. Analysis thus took 5-6 days to complete. Additionally diagnostic problems caused by the accompanying flora as well as the resistance to nalidixic acid occured. Within the scope of this study these problems could be solved by introducing a filtration step for the reduction of the accompanying flora and by performing the indoxyl acetate-hydrolysis-test in addition to the antibiotic-resistance-test. Besides various PCR protocols for the identification of thermotolerant campylobacters from food were established as an alternative to the cultural procedure, providing reliable results within two days. Furthermore, infrared spectroscopy was tested for the identification of Campylobacter isolates. Using this technique and with the help of a suitable data base, bacterial pure cultures can be differentiated within 2 hours. Among others 356 samples of raw poultry meat were tested with the newly established procedures as well as with the classical cultural method, showing that 32% of the samples were Campylobacter spp. positive. 37% of these isolates were resistant against nalidixic acid. This indicates that the development of resistances in Campylobacter spp. in Germany follows the same trend described for other European countries. 相似文献