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91.
Orla M Keane Jason D Keegan Barbara Good Theo de Waal June Fanning Michael Gottstein Mícheál Casey Christine Hurley Maresa Sheehan 《Irish veterinary journal》2014,67(1):16
Background
In 2013 a Technology Adoption Program for sheep farmers was established to encourage the implementation of best management practices on sheep farms in Ireland. There were 4,500 participants in this programme in 2013. As part of this programme, farmers had the option to carry out a drench test to establish the efficacy of their anthelmintic treatment.Results
Flock faecal samples were collected before and after treatment administration and gastrointestinal nematode eggs enumerated. In total there were 1,893 participants in the task, however only 1,585 included both a pre- and post-treatment faecal sample. Of those, 1,308 provided information on the anthelmintic product that they used with 46%, 23% and 28% using a benzimidazole (BZ), levamisole (LEV) and macrocyclic lactone (ML) product respectively. The remaining farmers used a product inapplicable for inclusion in the task such as a flukicide or BZ/LEV combination product. Samples were included for analysis of drench efficacy if the pre-treatment flock egg count was ≥200 eggs per gram and the interval post-sampling was 10–14 days for BZ products, 4–7 days for LEV products and 14–18 days for ML products. These criteria reduced the number of valid tests to 369, 19.5% of all tests conducted. If the reduction post-treatment was ≥95% the treatment was considered effective. Only 51% of treatments were considered effective using this criterion. There was a significant difference in efficacy between the anthelmintic drug classes with BZ effective in only 30% of treatments, LEV effective in 52% of cases and ML effective in 76% of cases.Conclusions
Gastrointestinal nematode anthelmintic treatments, as practiced on Irish farms, have a high failure rate. There was a significant difference between the efficacies of the anthelmintic classes with BZ the least effective and ML the most effective. 相似文献92.
Elisa Crisci Lorenzo Fraile Sonia Valentino Laura Martínez-Guinó Barbara Bottazzi Alberto Mantovani Maria Montoya 《Veterinary microbiology》2014
Long pentraxin 3 (PTX3) is a conserved pattern-recognition secreted protein and a host-defence-related component of the humoral innate immune system. The aim of the present study was to characterize swine PTX3 (SwPTX3) protein expression in influenza virus infected pigs. First, we performed in silico studies to evaluate the cross-reactivity of PTX3 human antibodies against SwPTX3. Secondly, we used in vitro analysis to detect SwPTX3 presence in swine bone marrow dendritic cells (SwBMDC) upon stimulation with different agents by Western blot and immunofluorescence. Finally, the levels of SwPTX3 were assessed in experimental infection of pigs with different strains of influenza virus. This is a novel study where the expression of SwPTX3 was evaluated in the context of a pathogen infection. The initial characterization of SwPTX3 in influenza virus infected pigs contributes to understand the role of PTX proteins in the immune response. 相似文献
93.
94.
Barbara Szonyi Amy Swinford Alfonso Clavijo Renata Ivanek 《Journal of Equine Veterinary Science》2014
In recent years, Texas has seen a dramatic increase in the number of clinical cases of Corynebacterium pseudotuberculosis (pigeon fever) infection in horses. Equine pigeon fever cases at Texas Veterinary Medical Diagnostic Laboratories (TVMDL) were analyzed with the objectives of investigating the spatiotemporal distribution and seasonal and annual trends of pigeon fever infection in horses in Texas between 2005 and 2011 and identifying high-risk areas and create a risk map for pigeon fever in horses in Texas. The study population consisted of horses culture-positive for C. pseudotuberculosis between January 1, 2005, and December 31, 2011 at TVMDL. The Poisson model of scan statistics was fitted to identify disease clusters. Empirical Bayesian smoothing was performed with the crude incidence estimates, followed by the geostatistical method of kriging to delineate high-risk areas. Cases increased 10-fold between 2005 and 2011. The annual cumulative incidence ranged from 9.3 to 99.5 per 100,000 horses at risk. Two seasonal peaks in the number of cases were observed in June and in December. Scan statistics identified a primary cluster in central Texas in 2011 (P < .0001 and relative risk of 9.2). Isopleth risk mapping also delineated a high-risk area in central Texas. High-risk areas were also detected in the panhandle and northern Texas. The epidemiological investigation supported anecdotal reports that pigeon fever is re-emerging in the Texas horse population. This study provides a baseline for future investigations of pigeon fever in the Texas horse population and serves as a reference for the disease distribution for veterinarians and horse owners. 相似文献
95.
Richard J Onders Steven D Mims Barbara A Wilhelm & Jesse D Robinson 《Aquaculture Research》2005,36(16):1602-1610
Paddlefish are gaining increasing acceptance as an aquaculture species worldwide. Commercial trout feeds, containing high protein and lipid levels, are currently used in intensive culture; however, nutritional requirements of paddlefish are not currently known. A study was conducted examining the effects on growth, survival and fillet composition of juvenile paddlefish when fed commercial feeds differing in protein and lipid levels. Paddlefish larvae were first stocked in 14.0 m3 round tanks and fed trout starter feeds for 43 days until trained to accept a 1.6 mm pellet. Paddlefish juveniles of mean weight (±SE) 20±0.27 g were randomly stocked into six0.02 ha ponds at 12 500 ha?1 and fed floating commercial trout or catfish (lower protein and lipid) feeds, twice daily (08:00 and 15:30 hours) for 92–97 days. At harvest, there were no significant differences in final weight, percent survival, specific growth rate , relative growth and feed conversion ratio between treatments, which averaged 223.6 g, 96.2%, 2.5% day?1, 10.2 and 1.98 respectively. Surface feeding activity index was significantly higher in ponds supplied with catfish feed than in ponds supplied with trout feeds. Relative pellet buoyancy was not a factor in feeding activity. Fulton's condition factor averaged0.238, was not significantly different, and was similar to a reported value for extensively cultured paddlefish (zooplanktivore). There was no significant difference in liver somatic index between treatments, which averaged 1.91%. Percent protein and moisture of fillets averaged 14.9% and 80.9%, respectively, and were not significantly different between treatments. However, lipid content of fillets was significantly higher in paddlefish fed the trout feed (4.45%), compared with paddlefish fed the catfish feed (2.42%). Fillet lipid content for both treatments was higher than reported values for extensively cultured paddlefish. Percent abdominal fat was significantly higher (0.82%) in paddlefish fed the trout feed compared with paddlefish fed the catfish feed (0.52%). Results from this study indicate that paddlefish can be fed a commercial catfish feed labeled to contain 32% protein and 4.5% lipid without adverse effects on growth, survival and fillet composition, lowering production costs. 相似文献
96.
Kathleen G. Haynes Xinshun Qu Barbara J. Christ 《American Journal of Potato Research》2014,91(3):254-259
Foliar late blight, caused by Phytophthora infestans, is an important disease problem worldwide. Foliar resistance to late blight was found in a hybrid population of the cultivated diploid species Solanum phureja-S. stenotomum (phu-stn). The objective of this study was to determine if resistance to late blight could be improved by recurrent maternal half-sib selection in the phu-stn population. Four clones from each of 72 maternal half-sib families plus the check cultivar ‘Atlantic’ were evaluated for late blight resistance in replicated field trials in Pennsylvania. The most late blight resistant clone from each of the 72 families was randomly intermated to advance the population. The cycle 1, 2, and 3 populations were evaluated in 1996–1997, 2003–2004, and 2009–2010, respectively. Percent infected foliage was recorded several times towards the end of the growing season and used to compute area under the disease progress curve (AUDPC). Mean AUDPC was 652 (cycle 1), 556 (cycle 2), and 276 (cycle 3), whereas the mean AUDPC of ‘Atlantic’ ranged from 775 to 863 each cycle. Narrow-sense heritability for resistance was estimated as 0.78, 0.77, and 0.80 in cycles 1, 2, and 3, respectively. Recurrent maternal half-sib selection continues to improve the levels of resistance to late blight in this diploid population with no adverse effect on the amount of additive genetic variance. Additional improvements for late blight resistance are likely to occur if this approach is continued. 相似文献
97.
Gary S. Burr Peng Li Jonathan B. Goff Delbert M. Gatlin III Barbara Grisdale-Helland Ståle J. Helland 《Journal of the World Aquaculture Society》2006,37(4):421-430
To investigate potential use of increasing nutritional density of diets for rapid growth of warm‐water fishes, a feeding trial was conducted in which growth performance, body indexes, and whole‐body composition of juvenile hybrid striped bass fed diets comprising protein (49, 54, and 59%), lipid (16, 20, 23, and 28%), and energy (22.0–25.1 kJ/g) concentrations beyond established minimum levels were compared to those of fish fed a more typical commercial reference diet (37.5% crude protein, 10.5% crude lipid, and 19.6 kJ/g energy on a dry matter basis). A subset of the experimental diets and the commercial reference diet also were fed to juvenile red drum. After 6 wk of feeding, hybrid striped bass fed the high‐protein and high‐lipid diets showed much greater growth performance compared to fish fed the commercial diet. Increasing dietary protein level, but not lipid level, tended (P ≤ 0.1) to enhance weight gain and feed efficiency of hybrid striped bass. Hepatosomatic index (HSI), intraperitoneal fat (IPF) ratio, and whole‐body protein were significantly (P < 0.01) influenced by dietary protein level. The dietary lipid and associated energy level had significant negative linear effects on daily feed intake. Linear regression analysis showed that dietary energy : protein ratio, largely influenced by dietary protein level, moderately but significantly influenced weight gain, HSI, IPF ratio, and whole‐body protein of hybrid striped bass and red drum. Red drum grew very similar to hybrid striped bass in response to the experimental diets. However, significant differences in HSI, IPF ratio, whole‐body protein, lipid, moisture, and ash between hybrid striped bass and red drum were observed, indicating species differences in protein and energy partitioning. In particular, the excessive lipid in the diet increased HSI and whole‐body lipid of red drum but not of hybrid striped bass. 相似文献
98.
99.
Barbara Sherman Simpson Mark G Papich 《Veterinary Clinics of North America: Small Animal Practice》2003,33(2):365-404, vii
As our knowledge expands, behavioral pharmacology plays an increasingly important role in behavioral medicine. Drugs traditionally categorized as anxiolytics, antidepressants, anticonvulsants, and hormones may be used to help manage a range of animal behavioral problems. Knowledge of how these agents act in the body and interact with other agents is imperative for safe and efficacious use. 相似文献
100.
The aim of this study was to examine the embryogenic potential of floral material of the cassava cultivar MCOL 1505. Macerated
immature inflorescences were found to be highly embryogenic, with almost 78% of the explants producing somatic embryos. Somatic
embryos were also produced from whole male florets and half florets although at much lower rates. No regeneration was obtained
from anther, microspore or floret wall tissue. Somatic embryos derived from immature inflorescences were regenerated via organogenesis
and the plants derived from this process were assessed in terms of phenotype and ploidy level. If haploid plants could be
produced by this method, this would have significant implications in assisting traditional cassava breeding, as this would
allow homozygosity to be reached more rapidly. In a crop such as cassava, which is highly heterozygous in nature, the use
of haploids in a breeding programme could considerably shorten the time taken to produce new desirable cultivars. This is
the first report on plant regeneration through somatic embryogenesis from floral tissue of cassava.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献