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Jacoby LL 《Science (New York, N.Y.)》1980,208(4450):1361-1362
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Pregnancy detection in cows by pulse mode ultrasound
Two commercially available pulse mode ultrasound instruments for pregnancy detection in cows were examined by testing 50 pregnant Friesian cows twice weekly. Absolutely reliable results were obtained after d 181 ("Cow-Tone") and d 221 of pregnancy (Preg-Alert 7 respectively. A newly constructed instrument ("HK-Rheintechnik") operating with greater wavelength (0,7 MHz) was tested in a similar fashion on 62 pregnant cows. Zt produced absolutely reliable results from d 135 of pregnancy on, i.e. 46 days sooner than the best of the commercial instruments tested .  相似文献   
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The effectiveness of casein hydrolyzate as mean to improve the welfare of cows induced into involution was tested in high yielding cows induced into dry-off by abrupt cessation of milking. Treatment with casein hydrolysate prevented build up of udder pressure in cows induced into dry off and was clearly associated with signs (lying behavior and step numbers) that they were calmer and more comfortable than cows induced into dry off by the conventional means. We conclude that treatment with casein hydrolyzate is a viable treatment tool that can prevent the suffering associated with drying-off of high-yielding modern dairy cows.  相似文献   
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Lignin, an important component of plant tissues, adsorbed five systemic fungicides and one herbicide (carbendazim, triadimefon, nuarimol, triarimol, fenarimol and fluometuron) more strongly than bovine serum albumin, cellulose, ethylcellulose or sodium polygalacturonate. Significant correlations were found between the extent of the adsorption of the pesticides on the lignins extracted from three different plant species, and the log Poet (Poet is the octan-1-ol/water partition coefficient) of the compounds. The more lipophilic fungicides triarimol and fenarimol (log Poet about 2.6) were adsorbed to the greatest extent. Fluometuron, triadimefon and nuarimol (log Poet about 2.0) were moderately adsorbed, whereas carbendazim with the lowest log Poet (1.34 at pH 5.0), was adsorbed more than expected from its Poet value. The anomaly of carbendazim is discussed; it is ascribed to it's partial protonation at pH 5.0, whereas the other pesticides were non-ionised.  相似文献   
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A lethal disease characterized by hemorrhage and necrosis of the brain, testes, and epididymides developed in young adult rats housed in specific pathogen free quarters. Morphological, virological, and serological investigations of the outbreak indicated that the probable causative agent was rat virus (Kilham), a common parvovirus of rats that usually induces persistent, asymptomatic infection in adult rats.  相似文献   
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Seventy seedlots of Leucaena leucocephala, L. pallida, L. diversifolia, L. retusa, L. esculenta, L. confertifolia, L. greggii and L. pulverulenta and various hybrid combinations were examined for survival to freezing weather, biomass production, leaf protein content and in vitro dry matter digestibility in Texas. Three sites along a 600 km north-south transect were chosen to provide a wide range in exposure to freezing weather. The minimum temperature on the warmer Three Rivers site was −7 °C while the minimum temperatures on the colder Vernon site was −14 °C. At the Three Rivers site where −7 °C temperatures occurred and where forage production was a priority and some winter frost damage was not a problem, L. leucocephala K636 and hybrids containing L. diversifolia and L. pallida have the most promise. If total lack of damage to −7 °C is essential, species such as L. retusa, L. pulverulenta (seedlot 61, 62) and hybrids such as L. retusa × L. greggii (53) and L. retusa × L. pulverulenta (55) have the greatest potential. This study examined only one family from each of the cold-hardy species as a parent in the promising hybrids. As extensive intraspecific genetic variation is present within these leucaena species there is great potential to find hybrids with much better combinations of cold hardiness, forage production, leaf protein and dry matter digestibility. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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