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排序方式: 共有328条查询结果,搜索用时 15 毫秒
61.
Jingping Guo Anneleen Swanepoel Joo Reis Guillaume Salze Melanie Rhodes Donald Allen Davis 《Aquaculture Nutrition》2020,26(2):368-381
A series of growth, feed stability and consumption trials were conducted to evaluate the efficacy of salmon by‐product in practical diets for Pacific white shrimp, Litopenaeus vannamei. This included a salmon by‐product meal (Salmon meal: SM) and a silage hydrolysate (hydrolysed salmon meal: HSM). The basal diet containing 120 g/kg SM was incrementally replaced (0. 25, 50, 75, 100%) by HSM to produce five test diets used in two trials. A sixth diet was included which evaluated gelatin supplementation (trial 1) or pH neutralization (trial 2). In trial 1, each diet was produced using two processing conditions (laboratory extruded and formed with meat grinder) and offered to shrimp in a clear water system. The results demonstrate that up to 50% of the SM can be used to replace with HSM; however, further increases resulted in reduced performance of shrimp. The addition of gelatin reduced leaching but there was limited effect of processing on leaching. There were no detectible effects of pH adjustment of the diets. Results indicated that the growth performance of shrimp has not influenced by HSM up to 60 g/kg to replace 50% of the SM in practical diets; however, higher levels resulted in significant decrease in performance. 相似文献
62.
Florida pompano Trachinotus carolinus is an important species in which the essentiality of taurine has been demonstrated, yet a quantitative requirement has not been estimated. Two experiments were conducted where a combined twelve diets were formulated with graded levels of taurine (ranging 1.6–41.6 g/kg dry matter) and fed to juvenile pompano (initial weight 7.73 and 4.37 g in trial 1 and 2, respectively). Dose responses were observed in terms of growth, feed efficiency and whole‐body taurine content, but there was no effect on survival. Several regression models were evaluated to determine the most appropriate one to draw conclusions from. A 4‐parameter saturation kinetic model was selected to model feed efficiency, while a 5‐parameter saturation kinetic model fitted the growth data (as thermal‐unit growth coefficient, TGC). A broken‐quadratic model served to estimate a breaking point in the whole‐body taurine content, although it also showed that whole‐body taurine kept increasing even at dietary levels in far excess of the requirement. The dietary taurine requirement was estimated at 2.5 g/kg (2.0–3.3 g/kg, 95% CI, dry matter basis) based on feed efficiency, while TGC was maximized at levels between 4.9 and 31.4 g/kg dietary taurine. 相似文献
63.
Synthesis and evaluation of hydroxyazolopyrimidines as herbicides; the generation of amitrole in planta 下载免费PDF全文
64.
Daub Matthias Hakl Ulrike Molendijk Leendert PG Schomaker Corrie Been Thomas H van Beers Thea G Jivishova Sevda Jivishov Emil Keusgen Michael Bluemel Roman Fischer Daniel Grundler Florian MW Reuther Marie Cappel Sabrina Bauer Harald Lang Christian Watrin Cliff den Nijs Loes JMF Van Bruggen Anne-Sophie Karssen Gerrit Kiewnick Sebastian Büchler Urs Roth Irma Frey Jürg 《植物病害和植物保护杂志》2015,122(4):189-193
Journal of Plant Diseases and Protection - 相似文献
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66.
Jonathan D. Bates Edward C. Rhodes Kirk W. Davies Robert Sharp 《Strength and Conditioning Journal》2009,62(1):98-110
Prescribed fire in rangeland ecosystems is applied for a variety of management objectives, including enhancing productivity of forage species for domestic livestock. In the big sagebrush (Artemisia tridentata Nutt.) steppe of the western United States, fire has been a natural and prescribed disturbance, temporarily shifting vegetation from shrub–grass codominance to grass dominance. There is limited information on the impacts of grazing to community dynamics following fire in big sagebrush steppe. This study evaluated cattle grazing impacts over four growing seasons after prescribed fire on Wyoming big sagebrush (Artemisia tridentata subsp. Wyomingensis [Beetle & Young] Welsh) steppe in eastern Oregon. Treatments included no grazing on burned and unburned sagebrush steppe, two summer-grazing applications after fire, and two spring-grazing applications after fire. Treatment plots were burned in fall 2002. Grazing trials were applied from 2003 to 2005. Vegetation dynamics in the treatments were evaluated by quantifying herbaceous canopy cover, density, annual yield, and perennial grass seed yield. Seed production was greater in the ungrazed burn treatments than in all burn–grazed treatments; however, these differences did not affect community recovery after fire. Other herbaceous response variables (cover, density, composition, and annual yield), bare ground, and soil surface litter did not differ among grazed and ungrazed burn treatments. All burn treatments (grazed and ungrazed) had greater herbaceous cover, herbaceous standing crop, herbaceous annual yield, and grass seed production than the unburned treatment by the second or third year after fire. The results demonstrated that properly applied livestock grazing after low-severity, prescribed fire will not hinder the recovery of herbaceous plant communities in Wyoming big sagebrush steppe. 相似文献
67.
Myers CJ Magdesian KG Kass PH Madigan JE Rhodes DM Marks SL 《Veterinary journal (London, England : 1997)》2009,181(2):137-144
This retrospective study describes the use of and complications associated with parenteral nutrition (PN) administration to 53 equine neonates at the University of California Veterinary Medical Teaching Hospital. Medical records were examined and information obtained on signalment, physical examination, clinical diagnosis, outcome, total hospitalization time, insulin administration, microbiology culture results, other complications (i.e. thrombophlebitis) and necropsy findings. Complete blood count and serum biochemistry analytes, venous blood gas, serum electrolyte and glucose concentrations, and blood lactate concentration results were compared before and during PN administration in all foals. Seventeen foals (32%) developed hypertriglyceridemia (>200mg/dL). Triglyceride concentrations >200mg/dL were significantly (P=0.049) associated with non-survival. Forty-seven foals (89%) developed hyperglycemia (blood glucose >120mg/dL) and eight (15%) developed catheter-related complications (thrombosis or local sepsis). Packed cell volume, total protein, creatinine, blood urea nitrogen, and sorbitol dehydrogenase concentrations decreased while foals were on PN, while serum chloride concentration increased. This study highlighted that hypertriglyceridemia during the acute phase of neonatal illness may be detrimental to outcome, and that the safety of lipid-containing solutions in foals warrants further study. 相似文献
68.
Leandro E. Miranda Giancarlo Coppola Hunter R. Hatcher Matthew B. Jargowsky Zachary S. Moran Michael C. Rhodes 《Fish and Fisheries》2021,22(1):128-140
Reservoirs are mostly managed at local scales as spatially independent units. A basin‐scale perspective may increase awareness at a broader scope and generate insight not evident at local scales. We examined the array of reservoir attributes and fisheries in the Mississippi Basin to identify management opportunities. The basin is the third largest in the world and includes over 1,700 reservoirs >100 ha, the most of any river basin. Our bird's‐eye view shows a piecemeal approach where reservoirs are mostly administered at the local level. Basin‐wide or catchment coordination to holistically address problems that recur across the basin is mostly lacking. A basin‐wide coordination arrangement could facilitate various facets of reservoir management. We reviewed governance arrangements in major river basins across the globe and concluded that the basin‐wide administrative layer we encourage for the Mississippi Basin may already exist in some basins but may not be directly applicable everywhere. 相似文献
69.
70.
Evaluation of the safety in dogs of long‐term,daily oral administration of capromorelin,a novel drug for stimulation of appetite 下载免费PDF全文
B. Zollers M. Huebner G. Armintrout L. C. Rausch‐Derra L. Rhodes 《Journal of veterinary pharmacology and therapeutics》2017,40(3):248-255
The objective of the study was to evaluate the safety of capromorelin, a ghrelin agonist that stimulates appetite and causes increased body weight and the release of growth hormone (GH). Beagle dogs (n = 32) received either oral placebo or 0.3, 7, or 40 mg/kg capromorelin once daily for 12 consecutive months. Safety was evaluated by physical examinations, including ECG and ophthalmic examinations, and comprehensive clinical pathology. Serum levels of capromorelin, GH, and insulin‐like growth factor 1 (IGF‐1) were measured periodically. Necropsies and histopathological evaluations were performed at study termination. As expected, GH and IGF‐1 levels were mildly increased in capromorelin‐treated dogs. Adverse events were limited to mild emesis and loose stools in all groups and excess salivation among some dogs receiving higher capromorelin doses. Clinical pathology testing was generally normal, although blood lipids and alkaline phosphatase levels were moderately increased among dogs receiving capromorelin. Treated dogs had slightly longer post‐treatment PR intervals seen on ECG, but with no changes in cardiac histopathology. Postmortem findings were normal. Drug‐related increases in liver weight were linked to overall increases in body weight. Capromorelin was well tolerated in dogs at daily doses up to 40 mg/kg for 12 months, demonstrating a wide safety margin. 相似文献