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221.
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Edwin H. Robinson JamesA. Steeby J. Robert Brent 《Journal of the World Aquaculture Society》1989,20(4):256-260
Two 7 day feeding trials were conducted with channel catfish swim-up fry to evaluate growth, feed conversion ratio, and body composition of fish fed one of the following feeds: salmon starter, catfish starter, or trout starter. Fish fed the salmon or trout starter feeds gained 50–75% more weight, converted feed more efficiently, and had higher body fat stores than fish fed the catfish starter feed. This may be related to the higher protein and energy content of these two feeds. It may be advantageous to feed salmonid starter feeds to hatchery reared catfish fry; however, it is not known whether or not the improved performance observed in the hatchery continues once the fish are stocked into nursery and grow out ponds. 相似文献
223.
R. A. S. White 《The Journal of small animal practice》1989,30(10):543-549
Sixty-two dogs with laryngeal paralysis were presented over a three year period. Presenting clinical signs included inspiratory stridor (100 per cent), exercise intolerance or syncopal episodes (81 per cent), loss or alteration in phonation (48 per cent) and coughing or gagging when eating (29 per cent). Causes of the paralysis were determined as traumatic (two dogs), neoplastic (two dogs), iatrogenic (two dogs), congenital (one dog) and idiopathic (55 dogs). Unilateral arytenoid lateralisation was performed in all dogs. The perioperative complication rate was approximately 10 per cent, while the success rate as judged by owners one year postoperatively was greater than 90 per cent. The technique avoided many of the recorded complications of intralaryngeal surgery. Operative times were short and the requirement for postoperative monitoring was minimal. Increasing familiarity with the technique favourably influenced the incidence of complications and the success rate. 相似文献
224.
M Steinhardt S Reimer J Kutschke U Bünger 《Archiv fuer experimentelle veterinaermedizin》1989,43(1):111-119
4 female and 2 male untrained fattening pigs, weighing 43.9 +/- 1.6 kg at the beginning of the experiment underwent continuous measurement of VO2, VCO2, and rectal temperature, prior to, during, and after running on a horizontal exercise belt set to speeds of 0.7, 1.3, and 2.5 m.s-1. The highest values of VO2 and VCO2 (ml-min-1/kg-1) and rectal temperature (degrees C) were usually measured few minutes after running. They were 18.84 +/- 3.65 and 20.4 +/- 4.53 as well as 41.2 +/- 0.4, 28.41 +/- 4.07 and 33.26 +/- 5.92 or 41.3 +/- 0.5, 26.21 +/- 7.7 and 32.32 +/- 7.14 as well as 40.5 +/- 0.7, depending on the above belt speeds. Exercise belt speeds of 1.3 to 1.8 m.s-1 were found to be suitable for testing aerobic metabolic capacity of untrained young pigs. 相似文献
225.
The spontaneous EEG and somatosensory evoked potentials (SEPs) were examined in chickens before and after electrical stunning using a waterbath stunner. Fifty-four per cent of the birds became epileptic and lost their SEPs, and 17% were non-epileptic and appeared to retain their SEPs. It was concluded that there was a reasonably close association between the presence of epileptiform activity in the EEG and the absence of SEPs following electrical stunning, but that the absence of SEPs could be preferred as an indicator of an effective stun on conceptual grounds. 相似文献
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A 3‐year‐old Burmese cat was presented with a history of nonresolving crusted and papular lesions of the face and prior treatment with prednisolone. Skin biopsies revealed typical pox lesions with hyperplasia and ulceration of the epidermis and eosinophilic cytoplasmic inclusion bodies in the epidermal cells. In the upper dermis there was prominent diffuse mast cell infiltration and mild neutrophilic and eosinophilic inflammation. Rare cytoplasmic inclusion bodies were also present in swollen endothelial cells of dermal venules, which showed no other degenerative changes. Histological diagnosis was confirmed by electron microscopic evidence of pox virus particles in inclusion bodies of epidermal cells. The lesions resolved within 6 weeks with systemic antibiotic therapy and supportive care. A 2‐year‐old domestic short‐haired cat was presented with multiple disseminated papular and ulcerative pox lesions with central eschar over the entire body. Histologically, large epidermal inclusion bodies (up to 6 μm in diameter) were present. Widespread haemorrhage and vascular wall necrosis was visible in the dermis and subcutis. Some subcutaneous vessels showed neutrophilic vasculitis. In addition to diffuse dermal neutrophilic and eosinophilic inflammation, a lymphohistiocytic panniculitis was also present. The cat died as a result of massive haemorrhage and lymphedema, despite supportive care. Funding: Self‐funded. 相似文献
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Abstract. Current tillage erosion models account for the influence of tillage direction in the magnitude of the soil (tillage) transport coefficient. It is argued here that this is counter-intuitive and causes significant problems in modelling tillage erosion in areas of complex terrain. This article examines whether a re-modelling of tillage erosion is possible that separates tillage direction (an interaction with the landform) from the soil transport coefficient (a measure of tillage intensity representing the combination of implement erosivity and soil erodibility). Experimental data for mouldboard ploughing upslope, downslope and cross-slope at Coombe Barton Farm, Devon are examined. Integration of data for all directions into a single relationship, which relates translocation in the direction of tillage to slope in the direction of tillage and translocation perpendicular to tillage to slope perpendicular to tillage, is not possible using previously published methods of analysis. However, when total translocation distance is regressed against the tangent of the slope at 45° to the tillage direction (bisecting the tillage direction and the direction of overturning) it is found that a single relationship can be used to describe tillage in all three directions. Therefore, this relationship is used to determine a single value of the soil transport coefficient ( k fTa ) for constant soil and implement conditions but different tillage directions. This redefinition of tillage is important both for true estimation of tillage erosion severity, the adirectional coefficient being 40% larger than the directional coefficient, and for modelling of tillage erosion in complex terrain. These improvements are vital when tillage erosion simulation is used to direct soil conservation strategies. 相似文献