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Deborah M. Thompson Frank W. Edens Gerald A. LeBlanc R. Michael Roe 《Pesticide biochemistry and physiology》2004,80(3):131-142
Trypsin modulating oostatic factor (TMOF), a peptide hormone originally isolated from the ovaries of adult Aedes aegypti, is currently under commercial development as a new pesticide chemistry with a novel mode of action for the control of larval mosquitoes. The objective of the current research is to evaluate potential risks of the use of TMOF as an insecticide on non-target organisms. TMOF (YDPAP6) was degraded in vitro (as determined by HPLC and LC/MS) to DPAP6, PAP6, and then AP6 by leucine aminopeptidase, a pancreatic enzyme found in the digestive system of vertebrates. The rate of degradation of TMOF and PAP6 was significantly greater than that of DPAP6, while no metabolism of AP6 was found. TMOF technical insecticide was produced on a commercial scale by recombinant yeast (heat-killed before application). The technical TMOF when administered in a single dose by gavage to male and female mice at 2000 mg dry weight/kg body weight produced no negative effects as compared to controls up to 12 days after treatment. When male and female mallard ducks were treated by gavage with 1250 mg dry weight of technical TMOF/kg body weight each day for 5 days, again no toxic effects were noted through 35 days after the last treatment. TMOF technical insecticide was also applied to the shaved skin of male and female rabbits at the rate of 2000 mg/kg for 1-2 days, with no effect. The end point observations in these in vivo experiments were mortality; changes in growth rate, behavior, body structure, and color; and possible lesions observed during necropsy. Finally, Daphnia incubated with technical TMOF in rearing water at the level of 1.0 × 106 yeast cells/ml (10 mg/ml) also demonstrated no negative effects on mortality, growth, molting, time to first brood, and production of viable neonates. It appears from these studies that TMOF can be degraded by vertebrate digestive proteases and technical TMOF is not toxic to the non-target organisms examined. 相似文献
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We incorporated explanatory factors including stream habitat type and fish density into individual‐based models with dynamic connections among adjacent habitat units to infer dispersal behaviour of juvenile steelhead Oncorhynchus mykiss in a Great Lakes watershed. We used mark–recapture data and an inverse modelling approach to estimate daily probability of steelhead moving out of a habitat unit, P(move), according to four competing models. The models used included (i) a null model where all fish had equal movement probability; (ii) a habitat‐dependent model where P(move) depended on the habitat type; (iii) a density‐dependent model of P(move); and (iv) a model where P(move) depended on both density and habitat type. The habitat‐dependent model provided the most parsimonious fit to the observed data according to Akaike's information criteria (AICc). In the null model, P(move) averaged 0.70, whereas P(move) averaged 0.75 in pools, 0.68 in riffles and 0.73 in runs in the habitat‐dependent model. 相似文献
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Ramona Weishaar Robin Wellmann Amelia Camarinha-Silva Markus Rodehutscord Jörn Bennewitz 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(1):14-22
Most traits in animal breeding, including feed efficiency traits in pigs, are affected by many genes with small effect and have a moderately high heritability between 0.1 and 0.5, which enables efficient selection. Since the microbiota composition in the gastrointestinal tract is also partly heritable and was shown to have a substantial effect on feed efficiency, the host genes affect the phenotype not only directly by altering metabolic pathways, but also indirectly by changing the microbiota composition. The effect of the microbiota composition on the breeding value of an animal is the conditional expectation of its breeding value, given the vector with microbiota frequencies, that is The breeding value of an animal can therefore be decomposed into a heritable contribution that arises from an altered microbiota composition and a heritable contribution that arises from altered metabolic pathways within the animal, so Instead of selecting for breeding value , an index comprising the two components and with appropriate weights, that is , can be used. The present study shows how this breeding strategy can be applied in pig genomic selection breeding scheme for two feed efficiency traits and daily gain. 相似文献
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Joaquin Araos Luca Lacitignola Claudia Acquafredda Caterina DiBella Marzia Stabile Erica Guacci Robin Gleed Salvatore Grasso Antonio Crovace Francesco Staffieri 《Veterinary anaesthesia and analgesia》2021,48(4):484-492
ObjectiveTo determine the specific lung elastance (SEL) in anesthetized dogs and to evaluate the efficacy of a SEL-based recruiting airway pressure (RPaw) at improving global and regional lung aeration.Study designRetrospective and prospective clinical study.AnimalsA total of 28 adult dogs were included in the retrospective study and six adult dogs in the prospective study.MethodsRetrospective study: SEL and SEL-based RPaw were determined using previously published data. In mechanically ventilated dogs undergoing thoracic computed tomography (CT), SEL was calculated as ΔPL/(VT/EELV), where ΔPL is the driving transpulmonary pressure, VT is the tidal volume and EELV is the end-expiratory lung volume. The ratio of lung to respiratory system elastance (EL/Ers) was determined. SEL and EL/Ers were used to calculate the SEL-based RPaw. Prospective study: dogs underwent thoracic CT at end-expiration and at end-inspiration using the SEL-based RPaw, and global and regional aeration was determined. For analysis of regional aeration, lungs were divided into cranial, intermediate and caudal regions. Regional compliance was also calculated. A p value <0.05 was considered significant.ResultsThe SEL and EL/Ers were 12.7 ± 3.1 cmH2O and 0.54 ± 0.07, respectively. The SEL-based RPaw was 29.1 ± 7.6 cmH2O. In the prospective study, the RPaw was 28.2 ± 1.3 cmH2O. During RPaw, hyperinflation increased (p = 0.0003) whereas poorly aerated (p < 0.0001) and nonaerated (p = 0.01) tissue decreased. Normally aerated tissue did not change (p = 0.265). Regional compliance was higher in the intermediate (p = 0.0003) and caudal (p = 0.034) regions compared with the cranial region. Aeration did not differ between regions (p > 0.05).Conclusions and clinical relevanceAn SEL-based RPaw reduces poorly and nonaerated lung tissue in anesthetized dogs. In nonsurgical anesthetized dogs, an RPaw near 30 cmH2O is effective at improving lung aeration. 相似文献
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Cristina de Miguel Garcia Luis Campoy Stephen Parry Julia E. Miller Manuel Martin-Flores Robin D. Gleed 《Veterinary anaesthesia and analgesia》2021,48(2):223-229
ObjectiveTo collect data about the current practice of recovering horses from general anesthesia and recovery personnel safety.Study designOnline survey.MethodsAn online questionnaire, including questions on general demographic data, recovery drugs, modality and characteristics of equine recovery and morbidity and mortality, was designed and distributed via e-mail to equine practitioners worldwide.ResultsPractitioners from 22 countries completed 373 questionnaires; 53% of the participants were board-certified equine surgeons, and the remainder were board-certified anesthesiologists (18%), large animal residents (8%), general practitioners (7%), large animal interns (6%), anesthesia residents (4.5%) and veterinary technicians (1.6%). Respondents were employed by academia (58%) or private practice (42%). Of the respondents employed at a university, 93% had a board-certified anesthesiologist on staff compared with 7% of respondents employed at a private practice. Most of the respondents assist horses during recovery, with 23% assisting every recovery and 44% assisting recovery in the majority of cases. Reasons for choosing to assist horses during recovery were: orthopedic procedures (57%), neurological deficits (49%), bad health (47%), history of poor recovery (44%), foals (42%), draft breeds (30%), magnetic resonance imaging (17%) and computed tomography (16%). Unacceptable recoveries were reported by 77% of participants. Commonly reported complications during recovery with any method were: orthopedic injury (66%), myopathy (54%), skin abrasion (53%) and airway obstruction (37%). The incidences of unacceptable quality of recovery (p = 0.09) or personnel injury (p = 0.56) were not different between assisted and nonassisted recoveries; however, more equine fatalities were reported for assisted recoveries (p < 0.006). Practitioners in academia reported more unacceptable recoveries (p < 0.0007) and personnel injuries (p < 0.002) compared with those in private practice.ConclusionsThe method of recovery differs among hospitals. Recovery personnel injuries associated with assisting horses during recovery are an important and previously unreported finding. 相似文献
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CORRELATIONS AMONG ULTRASONOGRAPHIC MEASUREMENTS OF OPTIC NERVE SHEATH DIAMETER,AGE, AND BODY WEIGHT IN CLINICALLY NORMAL HORSES 下载免费PDF全文
Stacy D. Cooley Peter V. Scrivani Margret S. Thompson Nita L. Irby Thomas J. Divers Hollis N. Erb 《Veterinary radiology & ultrasound》2016,57(1):49-57
Early diagnosis of high intracranial pressure (ICP) is critical for minimizing progressive brain injury due to reduced cerebral perfusion. In people, detecting enlargement of the optic nerve sheath diameter (ONSD) by transpalpebral ultrasonography has been found to be an accurate test for high ICP. Aims of this prospective, observational, cross‐sectional study were to test hypotheses that (1) ultrasonographic measurement of ONSD would be repeatable in horses, (2) have acceptable interobserver agreement, and (3) would be correlated with age and body weight. The sample population included 48 horses without clinical signs of high ICP and with varying ages and body weights. Two observers independently performed ONSD measurements in both eyes. All measurements ranged from 2.6 to 6.5 mm. The mean difference of repeated measures within observers was ≤0.1 mm and the coefficients of variation ranged from 5.0% to 8.8%. The mean difference of measures between observers was ≤0.2 mm. After correcting for performing multiple tests, no significant rank correlation (all r < 0.4 [absolute value]) was detected between ONSD and age or body weight. However, we observed smaller ONSD in foals versus adults (all P ≤ 0.002). In the foals, all observed measures of rostrocaudal and dorsoventral ONSD were <5 mm. In the adults, all observed measures of rostrocaudal and dorsoventral ONSD were ≤6.5 mm. Findings indicated that ultrasonographic ONSD measurement is a feasible test for use in horses of varying ages and sizes. Further investigation of this ultrasonographic measure as a clinical test for horse with suspected high ICP is warranted. 相似文献