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Justin D. Thomason Marc S. Kraus Tiffany L. Fallaw Clay A. Calvert 《The Canadian veterinary journal. La revue veterinaire canadienne》2016,57(3):297-298
Pacemakers were implanted in 4 client-owned female dogs which had persistent atrial standstill. Three dogs were alive after 14 to 39 months and 1 dog was euthanized after 10.5 years. This report demonstrates that some dogs with persistent atrial standstill can survive for extended time periods. 相似文献
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The risk of salmonellae shedding by dogs fed Salmonella-contaminated commercial raw food diets
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Finley R Ribble C Aramini J Vandermeer M Popa M Litman M Reid-Smith R 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(1):69-75
Twenty-eight research dogs were enrolled to determine the prevalence of salmonellae shedding after consumption of 1 Salmonella-contaminated commercial raw food diet meal. Sixteen dogs were exposed to Salmonella-contaminated commercial raw food diets and 12 to Salmonella-free commercial raw food diets. Seven of the exposed dogs shed salmonellae 1-7 days after consumption of Salmonella-contaminated raw food diets. None of the dogs fed Salmonella-free diets shed salmonellae. No clinical signs were observed in either group. Five of the 7 dogs shed the same serotypes as those recovered from food samples used for feeding. Results showed the same serotypes and antimicrobial resistance pattern in 2 of the 7 shedders. Dogs fed Salmonella-contaminated raw food diets can shed salmonellae and may, therefore, be a source of environmental contamination potentially leading to human or animal illness. 相似文献
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R. W. Mullen S. B. Phillips W. R. Raun G. V. Johnson W.E. Thomason 《Journal of plant nutrition》2013,36(5):673-681
Bermudagrass (Cynodon dactylon L.) is a warm season perennial that is well adapted in the southern Great Plains. It is one of the region's most important forage crops used for livestock production, and is commonly grown without legume interseeding. Recent research has investigated ways of improving the quality and quantity of this forage. The objectives of this study were to determine the effect of interseeded legumes and phosphorus (P) fertilizer on bermudagrass pasture forage yield and crude protein content. One experiment was initiated in 1993 in eastern Oklahoma in an established bermudagrass pasture. Red clover (Trifolium pratense L.), ladino clover (Trifolium repens L.), and two varieties of alfalfa (Medicago sativah), ’alfagraze’ and'common’, were interseeded by hand into an established stand of bermudagrass. The effect of P on forage yield and crude protein was evaluated using a 30‐kg P ha‐1 rate applied at establishment versus no applied P. Forage yield was collected three times throughout the growing season each year from 1994 through 1997. When both alfalfa varieties were interseeded into a bermudagrass pasture without applying additional P fertilizer, forage yields for the legume‐grass mixtures decreased below those obtained from the monoculture bermudagrass in the first year of the stand. The alfalfa variety ‘alfagraze’ interseeded into established bermudagrass decreased total forage yield over the entire 4‐yr study. Interseeded red clover and ladino clover increased crude protein of the forage compared with monoculture bermudagrass the first two years of the study, with red clover continuing to increase crude protein in the fourth year. However, when 30 kg P ha‐1 was applied to the bermudagrass prior to establishment of the legumes, no change in yield or protein was observed for both alfalfa varieties’ interseeding treatments versus the unfertilized mixtures. Although forage yield may not be increased, interseeding legumes into established bermudagrass could provide an efficient way to improve pasture crude protein without the use of inorganic fertilizers. However, if alfalfa ('common’ or ‘alfagraze') is interseeded, additional P may need to be applied at legume establishment to prevent possible yield decreases. 相似文献
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Toby G Knowles Steve N Brown Paul D Warriss Jeff Lines Ambrose Tinarwo Marta Sendon 《Aquaculture Research》2008,39(16):1731-1738
Food quality aspects of farmed turbot (Psetta maxima) were compared following two methods of slaughter: the current commercial method, by immersion in an ice slurry, which is then dewatered after approximately 20 min, or by first humanely, electrically stunning the fish using a prototype commercial stunner, before immersion in an ice slurry, which is dewatered after 20 min. Quality was assessed for up to 10 days of storage on ice following slaughter. No differences were found between the slaughter methods in terms of an overall carcass quality: overall appearance, haemorrhage, damage, burst gall bladder, staining of the body cavity by leakage from the gut or damage to the spine. No detectable difference was found between the treatments using the industry standard freshness scoring system, the Quality Index Method. Both groups of fish were classified as ‘Fresh’ after 10 days of storage on ice. Using objective measurements of colour, no differences between fish from either treatment were found in fillet colour. Changes in flesh pH were similar in electrically stunned and traditionally killed fish with a mean pH (±SE) at 2 h post‐mortem of 6.80±0.027 declining to 6.44±0.032 at 24 h post‐mortem. Humane electrical stunning of turbot at slaughter neither detectably improved nor decreased product quality as measured between 1 and 10 days of storage on ice. 相似文献
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Jeff Rutan 《Journal of Crop Improvement》2017,31(6):780-800
Weather uncertainty and soil spatial variability impact nitrogen (N) cycling and corn (Zea mays L.) growth, making accurate N predictions a challenge. Field studies were conducted in Lansing, Michigan, to evaluate a computer model (i.e., Adapt-N), a preseason year-based model (i.e., maximum return to N [MRTN]), and a crop sensor model (i.e., active canopy sensor with algorithm) for recommending corn N rates. To determine site-specific economic optimum N rates (EONR), five N rates were also applied (0, 33%, 66%, 133%, and 166% of the suggested MRTN) as starter + sidedress (SD) at V4. In a wet year (i.e., 2015), Adapt-N increased V8 SD N rates 35 kg N ha?1 relative to the MRTN V4 SD N application. Although the greater rate of N may have provided additional yield protection, no statistical yield differences were observed between the two models. The MRTN model increased partial factor productivity (PFP) 20% relative to Adapt-N. Limited expression of V8 corn N deficiency reduced crop sensor total N rates (21–56 kg N ha?1) and yield (0.82–1.05 Mg ha?1) relative to other models. In a drier year (i.e., 2016), N demand was reduced (EONR 64 kg N ha?1 less than 2015), resulting in similar corn response to all three models. Despite differences in actual corn N rate recommendations, all three models resulted in similar economic net returns across study years.Abbreviations: EONR, economic optimum nitrogen rate; MRTN, Maximum Return to Nitrogen; NUE, nitrogen-use efficiency; PFP, partial factor productivity; SBNRC, sensor-based nitrogen rate calculator; SD, side-dress 相似文献