Effects of high concentrations of dietary vitamin E and ethoxyquin on the performance of laying hens     

I Bartov  Y Weisman  E Wax 《British poultry science》1991,32(3):525-534

1. Three experiments were carried out with light strain laying hens to evaluate the effects of relatively high doses of dietary vitamin E (125 mg/kg food) or ethoxyquin (EQ) (250 mg/kg food) on their laying performance. The control diet contained 5 and 125 mg/kg vitamin E and EQ, respectively. The experimental diets were fed either from one or 32 weeks until 88 or 89 weeks of age. 2. The two antioxidants did not affect the growth of the pullets, age at first egg, final body weight, average egg weight or relative abdominal fat pad size and liver weight at the termination of the experiments. In two out of three experiments, vitamin E and EQ did not affect egg production, food efficiency or mortality; in the third experiment vitamin E significantly (P less than 0.05) improved egg production and food efficiency after an outbreak of Newcastle disease which occurred at 34 weeks of age. EQ significantly reduced mortality during the course of this experiment, but did affect the variables of performance. In two experiments vitamin E consistently improved shell density, although a significant effect was observed in only one of the eight determinations carried out. EQ did not affect this variable. 3. The uterine muscle was more susceptible to oxidation than the drumstick meat, as evaluated by TBA values. In both tissues, vitamin E significantly and consistently decreased TBA values and restricted their increase during incubation, while EQ was less effective, particularly in the drumstick meat. 4. It is concluded that increasing vitamin E and EQ concentrations in diets of laying hens have no effect on the decrease in egg production due to aging. However, vitamin E may minimize the decline in egg production and food efficiency following the outbreaks of some diseases and slightly improve--under certain yet undefined conditions--shell density.  相似文献   

In vitro synthesis of alfa fetoprotein by cultures of human liver cancer cells     

S Quelin  M Rioche  Y Bresson  R Masseyeff 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1973,26(3):299-303

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Ecological causes of predominance of some mammals as reservoirs of Leishmania tropica major in Turanian deserts.     

Y A Dubrovsky 《Folia parasitologica》1975,22(2):163-169

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THE MEASUREMENT OF BLOOD OXYGEN IN MALARIA WITH THE USE OF THE OXIMETER     

Wong YT 《Science (New York, N.Y.)》1945,102(2646):278-279

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BOSTON LETTER     

Y 《Science (New York, N.Y.)》1885,6(143):384-386

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Diluted rotifer, Brachionus plicatilis (Muller), extract as culture medium stimulates hatching of red sea bream, Pagrus major (Temminck & Schlegel)     

K Takii  M Nakamura  Y Tanaka  H Kumai 《Aquaculture Research》1995,26(4):243-247

Hatching rates and hatching times (50% hatch) of red sea bream, Pagrus major (Temminck & Schlegel), eggs in culture media that were prepared to dilute rotifer Brachionus plicatilis Muller extract at 4000-, 6000-. 8000- and 10 000-fold with artificial sea water (σ₁₅, = 24.0) were investigated. Although differences in hatching rate between the culture media and control artificial sea water were negligible, hatching time was significantly shorter in media at 4000- and 6000-fold dilutions than in media at 8000- and 10 000-fold dilutions and in the control artificial sea water, when the eggs immediately post spawning were incubated. The hatching rates of eggs at three developmental stages, immediately post-spawning, gastrula stage and heart-beat initiation stage, incubated respectively in the medium at 6000-fold dilution and the control, did not differ either, yet the hatching times at each egg stage in the medium were significantly shorter than that in the control. These results suggest that hatching enzyme secretion from the hatching glands is promoted to perceive chemical stimuli in the water-soluble fraction of rotifer extract via the embryo's chemoreceptors, from the heart-beat initiation stage to immediately before hatching, thus shortening the hatching time.  相似文献   

Design of field trials for the evaluation of antibacterial products for therapy of bovine clinical mastitis   总被引：1，自引：0，他引：1  

Y.H. SCHUKKEN  H.A. DELUYKER 《Journal of veterinary pharmacology and therapeutics》1995,18(4):274-283

In this paper, the design and statistical analysis of field trials for the evaluation of the efficacy of clinical mastitis therapeutics is covered. First, general issues underlying the design of clinical trials are reviewed. These include bias and confounding; randomization and blocking; and study objectives and choice of the corresponding hypothesis. Specific issues in the design of clinical mastitis trials are also discussed. Selection of subjects is discussed with regard to choice of experimental units, identification of reference population and study population, inclusion and exclusion criteria, and sample size calculation. Next, a section on treatment administration and evaluation of cure reviews treatment, blinding, choice of response measure, as well as compliance, withdrawal, and early termination. The statistical analysis section addresses possible statistical models, treatment of confounding, and fixed vs. random effects. In conclusion, well-conducted clinical mastitis trials represent an invaluable, albeit difficult and expensive, effort to evaluate efficacy and tolerance under usual circumstances of use.  相似文献   

Isolation of H3N2 swine influenza virus in South Korea.     

Dae S Song  Jae Y Lee  Jin S Oh  Kwang S Lyoo  Kyung J Yoon  Yong H Park  Bong K Park 《Journal of veterinary diagnostic investigation》2003,15(1):30-34

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Distribution of immunoglobulin-containing cells in calves inoculated orally with ruminal Bacteroides succinogenes and Selenomonas ruminantium     

S Sato  K Ogimoto  Y Nakai 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(4):719-725

Distribution of immunoglobulin(Ig)-containing cells was investigated in calves inoculated orally with live organisms of both Bacteroides succinogenes and Selenomonas ruminantium. Pathological changes and many Ig-containing cells were observed in calves which inoculated three times at 2, 3 and 26 days of age. Follicular germinal center was increased in number and size of the lymph nodes associated with the forestomach, suggesting activation of lymph apparatus. In the associated lymph nodes, IgG-containing cells were predominant and were located in both cortex and medulla, mainly in the medullary cord, B lymphocyte areas. Only a few IgA- and IgM-containing cells were observed in the lymph nodes. Accordingly, the inoculated bacteria may stimulate IgG-containing B lymphocyte populations. A few IgG-containing cells were detected in the mucosa of the forestomach. Ig-containing cells, predominantly IgG, were observed in the mucosa of the abomasum and intestine, and in the mesenteric lymph nodes. However, number of the cells in the mesenteric lymph nodes was smaller than that of the forestomach associated lymph nodes. The results suggest that the intraorally inoculated bacteria may stimulate the maturation of IgG positive lymphocytes in the lymph nodes associated with the forestomach.  相似文献   

Modification of DNA by chloroethylnitrosoureas     

Y Akaike 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(2):443-445

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