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61.
Responses of the two‐spotted oak buprestid,Agrilus biguttatus (Coleoptera: Buprestidae), to host tree volatiles
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62.
Nesar Ahmed Janet H. Brown James F. Muir 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):207-223
The livelihoods of a large number of farmers are associated with freshwater prawn (Macrobrachium rosenbergii) farming in gher (modified rice fields with high, broad peripheral dikes) systems in southwest Bangladesh. Most farmers integrated prawn with fish and rice in their gher and followed extensive methods using low inputs. Although farmers have improved their social and economic conditions through prawn farming, constraints include high production costs, low supply of wild fry and snail meat as prawn feed, lack of technical knowledge of farmers, and negative environmental impacts. 相似文献
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N. M. Cherry B. D. Lambert J. P. Muir 《Journal of animal physiology and animal nutrition》2010,94(5):665-669
Phosphorus (P) excretion in manure is a concern for dairy and beef producers. Excess P released into surface water runoff can lead to eutrophication and algal blooms in streams and lakes. One approach to reducing P excretion is to reduce dietary P. Data regarding P release from feedstuffs is limited and more precise formulations based on specific feed P release in the digestive tract may be one way to lower excreted P. In this experiment, the mobile nylon bag technique was used to determine the disappearance of P in corn silage, alfalfa hay, Coastal bermudagrass hay, and Tifton‐85 bermudagrass hay in steers after ruminal (24 h), ruminal + pepsin/HCl (rumen + PHCl), and ruminal + pepsin/HCl + intestinal (rumen + PHCl + I) incubation. Ruminal disappearance of P differed (p < 0.05) between feedstuffs and by site of incubation. Total tract (rumen + PHCl + I) P disappearance for corn silage, alfalfa hay, Coastal bermudagrass hay, and Tifton‐85 bermudagrass hay were 90.6%, 93.7%, 83.8% and 84.0% respectively. The range in P release (approximately 7%) indicates that considering P availability when balancing rations could have a measurable impact on subsequent P excretion from ruminants. More data concerning P availability as affected by other feed ingredients or plant species, maturity, and/or quality are needed to more accurately define P release from ruminant feeds. 相似文献
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Summary A standardised test of skin set (scuff meter) has been used to demonstrate the increase in skin adhesion of six varieties
following haulm destruction. Increases in skin adhesion were characteristically linear in the six varieties but increased
at different rates. At 49 days after haulm destruction, skin adhesion strengths were similar in all varieties except cv. Record
which had a much greater skin adhesion strength. Differences in skin adhesion strength were poorly related to skin morphological
characteristics such as skin thickness, cell size and suberin content. The method of haulm destruction affected skin adhesion
strength with skins adhering more rapidly and more strongly to the tuber following haulm pulling compared with either desiccation
with diquat or mechanical flailing. The method of haulm destruction did not influence skin morphological characteristics. 相似文献
68.
O'Brien T Baker TA Brounts SH Sample SJ Markel MD Scollay MC Marquis P Muir P 《Veterinary surgery : VS》2011,40(8):942-951
69.
Total allowable catch restrictions (hereafter referred to as catch quotas) play an important role in maintaining healthy fish stocks. While studies have identified a positive relationship between catch quota implementation and improved stock status, these methods are subject to selection bias as catch quotas are typically applied to stocks that are depleted. We address this challenge using the synthetic control method, which estimates the causal effect of catch quotas on fishing mortality and biomass by predicting a synthetic counterfactual outcome. We focus on high seas stocks (tunas, billfishes, and sharks) managed by tuna Regional Fisheries Management Organizations (tRFMOs), first providing an overview of stock status and current management measures in place. We find that implementation of catch quotas by tRFMOs has more than doubled over the past decade. Second, we predict the hypothetical fishing mortality and biomass trajectory for seven high seas quota-managed stocks in absence of a catch quota. These “synthetic non-quota stocks” are predicted using a weighted selection of high seas non-quota stocks. Credibility of the synthetic non-quota stocks is evaluated through diagnostic checks, and robustness tests assess sensitivity to study design. Five credible fishing mortality synthetic controls are predicted: three add support to the hypothesis that catch quotas successfully reduce fishing mortality, while two find that catch quotas increase fishing mortality. While our analysis is limited in scope, given that all seven quota-managed stocks are managed under a single tRFMO, we highlight the potential for the synthetic control method in fisheries management evaluation. 相似文献
70.
Analgesic, hemodynamic and respiratory effects of caudal epidurally administered ropivacaine hydrochloride in mares 总被引:1,自引:0,他引:1
Roman T Skarda Dr. med. vet. PhD Dip ACVA Dip ECVA ;William W Muir DVM PhD Dip ACVA Dip ACVECC 《Veterinary anaesthesia and analgesia》2001,28(2):61-74
Objective To determine the analgesic, hemodynamic and respiratory effects, sedation and ataxia in mares of caudal epidural administration of ropivacaine hydrochloride solution. Study design Prospective, single‐dose trial. Animals Ten healthy mares weighing from 475 to 565 kg. Methods Intravascular catheters and an epidural needle were placed after infiltration of the skin and subcutaneous tissues with 2% lidocaine. Ropivacaine (0.5%, 8 or 9 mL) was then injected epidurally at the fifth sacral or sacrococcygeal vertebrae, respectively. Analgesia was determined by lack of sensory perception to electrical stimulation (> 40 milliamps) and absence of response to needle pricks extending from coccyx to S2 dermatomes. Electrocardiogram, heart and respiratory rates, rectal temperature, arterial blood pressure, arterial acid‐base (pH, standard bicarbonate and base excess), gas tensions (PO2, PCO2), PCV, oxyhemoglobin and total solids concentrations, and numerical scores of perineal analgesia, sedation (head drop), and ataxia (position of pelvic limbs) were determined before and during a 5‐hour testing period. Analysis of variance (anova ) with repeated measures was used to detect significant (p < 0.05) differences of mean values from baseline. Results Epidurally administered ropivacaine induced variable analgesia extending bilaterally from coccyx to S2 (three mares), coccyx to S3 (four mares), and coccyx to S4 (three mares), with minimal sedation, ataxia, and cardiovascular and respiratory disturbances of mares. Perineal analgesia was attained at 10 ± 4 minutes and lasted for 196 ±42 minutes (mean ± SD). Five mares demonstrated inadequate perineal analgesia, probably attributable to deviation of the spinal needle from the midline. They were successfully blocked with ropivacaine on another occasion. Epidural ropivacaine significantly reduced repiratory rates of mares and did not change other variables from baseline. Conclusions and clinical relevance Ropivacaine (0.5%, 8 mL 500 kg?1) can be administered caudal epidurally to produce prolonged (> 2.5 hours) bilateral perineal analgesia with minimal sedation, ataxia, and circulatory and respiratory disturbances in standing mares. 相似文献