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151.
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K Ueland H Lutz 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(1):53-58
Serum samples from 224 Norwegian cats were analyzed for the presence of feline leukemia virus (FeLV) p27 common core antigen, and for antibodies to feline immunodeficiency virus (FIV). Ninety specimens originated from the serum bank at the central referral clinic at the Norwegian College of Veterinary Medicine, which had been collected during the years 1983-1989; 67 sera were submitted from veterinarian practitioners; while 67 sera originated from cats presented for euthanasia. The cats were classified into one "healthy" and one "sick" group. Only 2.2% of sick cats and 1.2% of healthy cats showed FeLV antigenemia, a finding which is lower than which has been reported from many other countries. The prevalence of FIV antibodies was 10.1% in sick cats and 5.9% in healthy cats. Antibodies to FIV was most prevalent in male cats (14.7%) than in female cats (2.1%), and more prevalent among domestic cats (12.0%) compared to pedigree cats (2.4%). Antibodies to FIV in the cats demonstrated increasing prevalence with increasing age. It may be concluded that FeLV causes minor problems in Norwegian cats, while FIV is present in a similar prevalence to what is reported from other countries. 相似文献
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The cellularity of subcutaneous adipose tissue of 108 male castrated pigs (German Landrace) was investigated. The tissue was taken bioptically under anesthetic conditions. The outer and the inner layer of backfat were examined separately, fresh unfixed tissue slices floating in Ringer solution were subjected to microscopic measurements of adipocyte diameters. The animals were kept in feeding experiments, 3 and 2 sectors respectively of growing period were examined (40 kg; 66 kg, 88 kg body mass) divided into 6 and 4 feeding levels respectively for 21 days (0.4; 0.6/0.8; 1.0; 1.2; 1.4 MJ metabolic energy per kg body mass0.75 per day). The inner layer of backfat showed bigger fat cells compared to the outer layer. The average fat cell size was greater for the older and heavier than for the younger animals. The gradation of food administration resulted not in a straight parallel rise in fat cell size but in an effective consequence with respect to the distribution frequency of the dates: The higher the food energy level, the more the accumulation of small fat cells from 10 til 30 microns diameter. These cell fractions succeeded in being signified as typical and important closed population. Other authors also had described these particular cells, i.e. "fat cell clusters" and "VSFC" (= very small fat cells) respectively. An external use of the dates for computer simulation programs resulted in success and manifested the independently gained conclusions. The examinations were performed by support of different branches of literature and the results had to be discussed in front of a wide background of known connections.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
160.
Taste aversion learning in horses 总被引:1,自引:0,他引:1
The ability of ponies to learn to avoid a relatively novel food associated with illness was tested in three situations: when illness occurred immediately after consuming a feed; when illness occurred 30 min after consuming a feed; and when illness was contingent upon eating one of three feeds offered simultaneously. Apomorphine was used to produce illness. The feeds associated with illness were corn, alfalfa pellets, sweet feed and a complete pelleted feed. The ponies learned to avoid all the fees except the complete feed when apomorphine injection immediately followed consumption of the feed. However, the ponies did not learn to avoid a feed if apomorphine was delayed 30 min after feed consumption. They could learn to avoid alfalfa pellets, but not corn, when these feeds were presented with the familiar "safe foods," oats and soybean meal. Ponies apparently are able to learn a taste aversion, but there were constraints on this learning ability. Under the conditions of this study, they did not learn to avoid a food that made them sick long after consumption of the food, and they had more difficulty learning to avoid highly palatable feeds. 相似文献