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951.
1. Automatic weighing equipment was tested on a flock of 752 roaster chickens reared on litter to 10 weeks of age.
2. Mean body weights obtained automatically were lower than those obtained manually, mainly because of birds perching on the automatic weighing perch with part of their body in contact with the floor.
3. Birds observed on the weighing perch on one day of the week were 3–5 times more likely to use the perch again on the following 2 d than expected on the basis of random perch use by flock members. These birds were also more likely to be seen in the area immediately surrounding the perch than in similar areas elsewhere in the pen. 相似文献
952.
Shapiro JL Rostkowski C Little PB Smith-Maxie L Julian RJ Van Dreumel AA 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(5):155-158
Caprine β-mannosidosis, a fatal inherited deficiency of the lysosomal enzyme β-mannosidase, was diagnosed in neonatal female Nubian crossbred twin kids from a small herd near Guelph, Ontario. The kids had been tetraplegic since birth, with whole body tremors, abnormal nystagmus and an intention tremor of the head. 相似文献
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The lungs of 334 pigs were obtained from two slaughter plants in Minnesota and examined in detail. Macroscopic and microscopic evaluation, direct fluorescence for Mycoplasma hyopneumoniae and bacterial culture were done on all of them and a subsample of 50 were selected for virus culture. Mycoplasma hyopneumoniae, Pasteurella multocida and Haemophilus spp. were detected in 24.0%, 34.1% and 27.0% of the lungs, commonly in conjunction with each other. One isolate of Haemophilus pleuropneumoniae serotype 2 was detected and this represents the first report of its presence in the United States. No virus was detected in any of the lungs. Lungs with both M. hyopneumoniae and Pasteurella multocida had the greatest amount of macroscopic pneumonia (9.8% of the lung). Lungs with M. hyopneumoniae or P. multocida alone had 4.9% and 5.2% of the lung involved with pneumonia respectively. Lungs with Haemophilus sp. Taxon "minor group" had 3.8% of the lung involved which was not significantly different from lungs with none of these organisms being detected (1.6%). There was a positive correlation between the extent of M. hyopneumoniae infection, as scored by FAT and the amount of macroscopic pneumonia present (r = 0.46; P less than 0.001). Likewise, there was a positive correlation between the estimated concentration of P. multocida present, as scored by the relative number of colonies on blood agar and the amount of macroscopic pneumonia present (r = 0.60; P less than 0.001). Microscopically, the amount of lymphoreticular proliferation, polymorphonuclear cells and alveolar macrophages were evaluated.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
955.
Akers SW Mitchell CA 《HortScience : a publication of the American Society for Horticultural Science》1985,20(4):684-686
Periodic seismic (shaking) stress influenced the growth of sexual and asexual reproductive structures of three cultivated species. It delayed anthesis of Lycopersicon esculentum Mill. 'Patio' but not of Tagetes erecta L. 'Jubilee' or Solanum tuberosum L. 'Kennebec'. Shaken 'Jubilee' marigold plants produced the same number of flowers as undisturbed plants, but flowers of shaken plants were smaller. In contrast, seismic-stressed 'Patio' tomato produced fewer buds and flowers, but fruit set was enhanced relative to that of controls. Seismic stress also reduced tuber weight of 'Kennebec' potato, whereas tuber number was unaffected. The overall effect of seismic stress was to reduce the growth of reproductive structures and, in some cases, the number of reproductive structures that developed. 相似文献
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