Association between the genetic similarity of the open reading frame 5 sequence of Porcine reproductive and respiratory syndrome virus and the similarity in clinical signs of Porcine reproductive and respiratory syndrome in Ontario swine herds     

Thomas Rosendal  Cate Dewey  Robert Friendship  Sarah Wootton  Beth Young  Zvonimir Poljak 《Canadian journal of veterinary research》2014,78(4):250-259

A study of Ontario swine farms positive for Porcine reproductive and respiratory syndrome virus (PRRSV) tested the association between genetic similarity of the virus and similarity of clinical signs reported by the herd owner. Herds were included if a positive result of polymerase chain reaction for PRRSV at the Animal Health Laboratory at the University of Guelph, Guelph, Ontario, was found between September 2004 and August 2007. Nucleotide-sequence similarity and clinical similarity, as determined from a telephone survey, were calculated for all pairs of herds. The Mantel test indicated that clinical similarity and sequence similarity were weakly correlated for most clinical signs. The generalized additive model indicated that virus homology with 2 vaccine viruses affected the association between sequence similarity and clinical similarity. When the data for herds with vaccine-like virus were removed from the dataset there was a significant association between virus similarity and similarity of the reported presence of abortion, stillbirth, preweaning mortality, and sow/boar mortality. Ownership similarity was also found to be associated with virus similarity and with similarity of the reported presence of sows being off-feed, nursery respiratory disease, nursery mortality, finisher respiratory disease, and finisher mortality. These results indicate that clinical signs of PRRS are associated with PRRSV genotype and that herd ownership is associated with both of these.  相似文献   

From Matterhorn to Mt Everest: Empowering Rescuers and Improving Medical Care in Nepal     

Monika M. Brodmann Maeder  Buddha Basnyat  N. Stuart Harris 《The Forestry Chronicle》2014,25(2):177-181

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The effect of vitamin E on the serum complement activity of the rainbow trout, Oncorhynchus mykiss (Walbaum)     

J. Pearce  J.E. Harris  & S.J. Davies 《Aquaculture Nutrition》2003,9(5):337-340

Rainbow trout were fed three experimental diets with varying levels of vitamin E (α‐tocopherol) supplementation (0, 100 and 1000 mg kg^?1 diet), and the effects of feeding these diets on serum spontaneous haemolytic activity and classical complement activity were investigated. Hepatic α‐tocopherol levels reflected the dietary intake of the vitamin. Fish fed the diet deficient in vitamin E showed reduced growth and increased mortality. Their hepatosomatic index and erythrocyte fragility was significantly higher than both the supplemented groups and haematocrit, and complement activity were all significantly lower. There appeared to be some enhancement of serum complement activity correlated with increased dietary supplementation with vitamin E but the benefits of supplementation at levels above those currently recommended were not established.  相似文献   

Interannual variability of Calanus helgolandicus in the English Channel     

Xabier Irigoien  Roger P. Harris 《Fisheries Oceanography》2003,12(4-5):317-326

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Effects of oxygen supersaturation and temperature on juvenile greenlip, Haliotis laevigata Donovan, and blacklip, Haliotis rubra Leach, abalone     

James O Harris  Christopher M Burke  Stephen J Edwards  & Deon R Johns 《Aquaculture Research》2005,36(14):1400-1407

Growth and survival of juvenile greenlip (39.03 (SD 3.80) mm (n=524)) and blacklip (31.92 (SD 4.19) mm (n=531) abalone were investigated at high dissolved oxygen levels (95–120% saturation) between 17 and 19°C. Abalone were fed the same artificial diet and each species was contained in groups of approximately 30 individuals within triplicate tanks for each of six treatments and were exposed to flow through water adjusted to give experimental conditions for up to 75 days. Blacklip abalone held at 16.9°C and 97% oxygen saturation grew in shell length significantly faster than all other treatments of blacklip abalone held at 19°C, and significantly faster than blacklip abalone maintained at 111% oxygen saturation and 17.5°C. Both temperature and oxygen saturation significantly affected the survival of this species. Blacklip abalone held at 19°C had significantly lower survival for both 96% oxygen saturation and 120% oxygen saturation, compared with blacklip abalone maintained at either 110% oxygen saturation and 19°C, or for any 17°C treatment. No significant differences were noted for greenlip abalone within the range tested in terms of growth rate, food consumption rate or survival, indicating that greenlip abalone tolerated these conditions better than did blacklip abalone.  相似文献   

Nitrogen excretion and absorption efficiencies of white steenbras, Lithognathus lithognathus CuvieSparidae, under experimental culture conditions     

S A Harris  T Probyn 《Aquaculture Research》1996,27(1):43-56

The various components of the nitrogen budget of white steenbras,Lithognathus lithognathus Cuvier (Sparidae), were determined under experimental culture conditions. A simple closed system respirometer was used where experiments were conducted to investigate faecal prodution, nitrogen excretion rates and absorption efficiencies at 16C and 20C. Faecal loss, as a percentage of the ingested nitrogen, amounted to 3.59%. Gross, carbon and nitrogen absorption efficiencies ranged from 8 6 to 9 8 % and were not significantly affected by fish size, ration size or temperature (P < 0.05). Net protein utilization (NPU) and the biological value (BV) ranged from 78 to95%. Ammonia and urea constituted 77.93 and 10.07%, respectively, of the total exogenous nitrogen excretion, the balance being made up of other dissolved organic nitrogen (DON). Endogenous ammonia excretion rates were significantly greater in small fish compared to large fish (P < 0.05). Total non-faecal losses as a percentage of the ingested ration amounted to 21.86%. Fish size and ration size increased nitrogen excretion, but temperature had no effect. Maintenance rations were 7.55 mg g-¹ dry weight day-¹ (0.76%dry body weight) and 5.99 mgg-¹ (0.60% dry body weight) for small and large fish, respectively. The high absorption efficiencies and high nitrogen indicated that white steenbras utilize the commercial trout pellet diet very efficiently.  相似文献   

Conservation status of the world's hagfish species and the loss of phylogenetic diversity and ecosystem function     

Landon Knapp  Michael M. Mincarone  Heather Harwell  Beth Polidoro  Jonnell Sanciangco  Kent Carpenter 《水产资源保护:海洋与淡水生态系统》2011,21(5):401-411

Laboratory testing in pet avian medicine.     

D J Harris 《Veterinary Clinics of North America: Small Animal Practice》1991,21(6):1147-1156

The importance of employing laboratory diagnostics in the examination of avian patients cannot be overemphasized. The physical examination alone is grossly insufficient. Many avian illnesses do not display external signs, and laboratory work is imperative in detecting them. Only after the assessment of various laboratory parameters can an examination be considered complete.  相似文献   

Computer simulation model of swine production systems: I. Modeling the growth of young pigs   总被引：1，自引：0，他引：1  

C Pomar  D L Harris  F Minvielle 《Journal of animal science》1991,69(4):1468-1488

Theoretical concepts and relationships were used to develop a deterministic pig growth model. The model predicts, in a continuous form, growth and body composition of boars, barrows, and gilts according to genotype, diet, and management conditions. The model is aggregated at the whole-animal level with three main elements of body composition; total body DNA, total body protein mass (PT), and total body mass of lipids, with PT determining the secondary elements of ash and moisture. The primary factors regulating growth were associated with cellular hyperplasia and hypertrophy in agreement with the basic concepts described by Baldwin and Black (1979). Differential equations representing DNA accretion and protein synthesis and degradation were adapted from Oltjen et al. (1985). Normal pig protein growth was characterized from published data. Body PT was used to reflect several metabolic activities related to animal size and age, as in some prior models. Dietary energy and protein were used in sequence until requirements are satisfied, first for maintenance, then for protein growth, and finally for fat deposition. A comparison between experimental and simulated results illustrates that the model may simulate growth and body composition of young pigs adequately.  相似文献   

关于库拉索芦荟     

Beth Lulinski  Cathy Kapica  贺敏 《中国农村科技》2006,(10):35-35

芦荟是一种非常好的室内植物,它作为一种用途广泛的民间药物有着悠久的历史。最常为人知的是库拉索芦荟,这个植物能够分成两个基础的产品,即凝胶和乳汁。库拉索芦荟凝胶是叶子的果肉或者黏液,这是一种能够从软组织中得到的稀薄的清澈的果冻样物质,这个软组织由芦荟叶内部的一部  相似文献