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131.
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N. Künzi C. Gaillard H. Leuenberger M. Schneeberger F. Weber 《Livestock Production Science》1978,5(3):245-252
The mating of small beef type bulls (Angus, Eringer) to reduce difficulties at first calvings is increasingly applied in Switzerland. In contrast to this, calf producers refuse to use large type beef bulls on their cows because of direct and indirect damages due to increased calving problems. It proved to be an attractive alternative to use specially selected dual purpose bulls tested for ease of calving and high growth rate but low dairy performance, so called M-bulls (Meat bulls), out of the regular AI testing programme for Braunvieh and Simmentals.From 1974 to 1976, Charolais, Limousin and Piemontese bulls were included in the AI testing programme and compared with Braunvieh- and Simmental-M-bulls. Data included progeny from 47 bulls, 7936 calvings, 1137 animals with carcass gains, and 130 dissected carcasses. If calving performance and net gains are considered, the M-bulls compete well with the foreign breeds. If, in addition, the amount of meat in the carcass is taken into account, then Charolais and Piemontese crosses are superior. The problem is one of distributing gains and losses among calf producers, feeders and butchers. It needs specially tested bulls with emphasis on ease of calving out of the specialized beef breeds or sire lines to persuade the dairy farmer to cross his cows. 相似文献
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P M Beaumier J D Fenwick A J Stevenson M P Weber L M Young 《Equine veterinary journal》1987,19(3):207-213
Plasma and urinary levels of salicylic acid were examined in Standardbred mares after administration of various feeds, containing different compositions of hay. In addition, horses were administered acetylsalicylic acid orally and methyl salicylate topically. Elevated salicylic acid levels were observed in horse urine and plasma in animals fed lucerne hay. The plasma and urinary elimination of salicylic acid exhibited a diurnal pattern which was related to the type of feed and the feeding schedule. Within 24 h after oral administration of acetylsalicylic acid, plasma and urine salicylic acid levels were consistent with residual levels observed after feeding lucerne hay. Elimination of salicylic acid was rapid and complete, with a half-life between 5 and 7 h. Topical administration of methyl salicylate (8.4 g) produced elevated urinary salicylic acid levels for 6 h. A smaller dose of methyl salicylate (3.4 g) did not elevate plasma or urine salicylic acid levels above those observed following administration of lucerne hay. 相似文献
136.
Cytogenetics in the dog and cat 总被引:2,自引:0,他引:2
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Medium- and long-chain dialkyl 3,3'-thiodipropionate antioxidants such as dioctyl 3,3'-thiodipropionate, didodecyl 3,3'-thiodipropionate, dihexadecyl 3,3'-thiodipropionate, and di-(cis-9-octadecenyl) 3,3'-thiodipropionate were prepared in high yield by lipase-catalyzed esterification and transesterification of 3,3'-thiodipropionic acid and its dimethyl ester, respectively, with the corresponding medium- or long-chain 1-alkanols, i.e., 1-octanol, 1-dodecanol, 1-hexadecanol, and cis-9-octadecen-1-ol, in vacuo (80 kPa) at moderate temperatures (60-80 degrees C) without solvents. Immobilized lipase B from Candida antarctica (Novozym 435) was the most active biocatalyst for the preparation of medium- and long-chain dialkyl 3,3'-thiodipropionates showing enzyme activities up to 1489 units/g, whereas the immobilized lipases from Rhizomucor miehei (Lipozyme RM IM) and Thermomyces lanuginosus (Lipozyme TL IM) were by far less active ( approximately 10 enzyme units/g). Maximum conversions to dialkyl 3,3'-thiodipropionates were as high as 92-98% after 4 h of reaction time. Similarly, dihexadecyl 2,2'-thiodiacetate was prepared in high yield using 2,2'-thiodiacetic acid or diethyl 2,2'-thiodiacetate and 1-hexadecanol as the starting materials and Novozym 435 as the biocatalyst. 相似文献