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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
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The relationships among rate of ultrasound acoustic emission (AE), xylem water potential and transpiration rate were investigated in 5-year-old potted saplings of Picea abies Karst. after cycles of water stress. Water-stressed plants displayed minimum xylem water potentials of -3.9 MPa, near-zero transpiration rates and up to 45 AE counts per minute. After rewatering, water-stressed plants no longer produced AEs. Well-watered control plants produced only a small number of ultrasonic AEs. After three cycles of water stress (lasting 24 days in total), it was estimated that about two-thirds of the functional tracheids were embolized. The concomitant reduction in hydraulic conductance was about 70%. 相似文献
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Rickets was diagnosed in two weaner alpacas from a flock showing ill thrift and lameness during the winter of 1992. Both animals had abnormally shaped ribs with occasional healing fractures, irregular thickening of growth plates and metaphyseal haemorrhages. The mean serum phosphorus concentrations of the alpacas fell during June and July, even though lambs grazing the same pasture had normal serum phosphorus concentrations and the phosphorus concentration of the pasture was considered adequate. Vitamin D deficiency may also have contributed to the osteodystrophy. The alpacas had a thick fleece during the winter, and diurnal Vitamin D, synthesis resulting from solar irradiation is likely to have been minimal, especially considering the reduced sunshine hours recorded during the 1992 winter. Surviving alpacas recovered after treatment with monosodium phosphate and an oral Vitamin D supplement. It is possible alpacas are more susceptible to deficiencies of phosphorus and Vitamin D than other grazing animals in New Zealand. 相似文献
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CLINICAL AND MAGNETIC RESONANCE IMAGING FEATURES OF INFLAMMATORY VERSUS NEOPLASTIC MEDIAL RETROPHARYNGEAL LYMPH NODE MASS LESIONS IN DOGS AND CATS
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Philippa J. Johnson Richard Elders Pascaline Pey Ruth Dennis 《Veterinary radiology & ultrasound》2016,57(1):24-32
Medial retropharyngeal lymph node (MRLN) mass lesions are a common cause of cranial cervical masses in dogs and cats, and are predominantly due to metastatic neoplasia, primary neoplasia, or inflammatory lymphadenitis. The purpose of this retrospective cross‐sectional study was to test the hypothesis that clinical and magnetic resonance imaging (MRI) characteristics for dogs and cats with MRLN mass lesions would differ for inflammatory vs. neoplastic etiologies. Dogs and cats with MRLN mass lesions that had undergone MRI and had a confirmed cytological or histopathological diagnosis were recruited from medical record archives. Clinical findings were recorded by one observer and MRI characteristics were recorded by two other observers who were unaware of clinical findings. A total of 31 patients were sampled, with 15 in the inflammatory lymphadenitis group and 16 in the neoplasia group. Patients with inflammatory lymphadenitis were more likely to be younger and present with lethargy (P = 0.001), pyrexia (P = 0.000), and neck pain (P = 0.006). Patients with inflammatory lymphadenitis were also more likely to have a leukocystosis (P = 0.02) and segmental neutrophilia (P = 0.001). Inflammatory masses were more likely to have moderate or marked MRI perinodal contrast enhancement (P = 0.021) and local muscle contrast enhancement (P = 0.03) whereas the neoplastic masses were more likely to have greater MRI width (P = 0.002) and height (P = 0.009). In conclusion, findings indicated that some clinical and MRI characteristics differed for dogs and cats with inflammatory vs. neoplastic medial retropharyngeal lymph node masses. Although histopathological or cytological diagnosis remains necessary for confirmation, these findings may help with the ranking of differential diagnoses of future cases. 相似文献
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Tracey Jones Ruth Feber Gabriel Hemery Paul Cook Katy James Curt Lamberth Marian Dawkins 《Agricultural Systems》2007
The commercial, welfare and environmental impacts of rearing small colonies of free-range chickens in newly planted woodland at two sites in the UK, during the first 2 years of the enterprise, were investigated. Newly planted rather than established trees were used so that commercially viable species could be planted in a way that would suit the management of the chicken enterprise, and small colonies were used so that farmers wishing to diversify could buy into the system progressively. It was anticipated that marketing a high specification product would provide an immediate income, whilst waiting for the future investment in trees to grow. 相似文献
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Mercedes Fernandez-Moreno Alberto Arias-Perez Ruth Freire & Josefina Méndez 《Aquaculture Research》2008,39(5):474-481
Aequipecten opercularis (Queen scallop) and Mimachlamys (Chlamys) varia (Black scallop) are important natural resources occurring in Atlantic and Mediterranean coasts. To develop an optimal sustainable exploitation plan, it is important to study the genetic structure of the different populations. In this study, we used polymerase chain reaction‐restriction fragment length polymorphisms for the determination of the genetic variation and population structure of these two species in different localities. Ten composite haplotypes were generated for A. opercularis and 15 haplotypes for M. varia. Of these, six and four were unique respectively. The analysis of the distribution of the different haplotypes between the localities showed no clear evidence of subdivision in A. opercularis, while in M. varia the results indicated that the two localities analysed should be managed as separate stocks. 相似文献