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121.
122.
Dimitrios G Karpouzas Ioannis O Giannakou Allan Walker Simon R Gowen 《Pest management science》1999,55(11):1089-1094
Soils were collected from a potato-growing area in Serres, Northern Greece, where the nematicide ethoprophos was reported to have lost its effectiveness against cyst nematodes following 30 years of regular use. Incubation studies with ethoprophos and two bioassays using root-knot nematodes demonstrated that, in this heavily treated soil, the nematicide was degraded rapidly and nematicidal activity persisted only up to 14 days. In soil from an adjacent field with no known history of nematicide use during the preceding 14 years, ethoprophos was degraded more slowly and retained its nematicidal activity for more than 35 days. Ethoprophos efficacy was extended when the soil that had been treated in the field was autoclaved, although the effect was only transitory. The addition of ‘pre-conditioned’ soil from the previously treated field to samples of soil from the previously untreated field resulted in a significant acceleration of ethoprophos degradation compared with that observed in unamended soil from the previously untreated field. © 1999 Society of Chemical Industry 相似文献
123.
124.
In laboratory incubations, the times to 50% loss (DT50) of a first application of napropamide were approximately 25, 45 and 75 days in soil incubated at 25, 15 and 5°C respectively. When treated for a second time, the DT50 values were 4, 7 and 15 days at the same temperatures, irrespective of the temperature of the first incubation. This indicates that enhanced degradation of napropamide in soil can be both induced and expressed at low temperature. A mixed microbial culture able to degrade the herbicide to a single degradation product, identified by HPLC retention time as naphthoxypropionic acid, was obtained from a soil capable of rapid degradation. Addition of a sub-sample of this mixed culture to a previously untreated soil introduced rapid degrading ability. When small amounts of soil capable of rapid degradation were added to previously untreated soil, in both the laboratory and the field, the degradation rate of napropamide increased compared with that in unamended soils. 相似文献
125.
Oren Shelef Ofer Guy Elaine Solowey Michael Kam A. Allan Degen Shimon Rachmilevitch 《Arid Land Research and Management》2016,30(2):209-228
With globalization in the last century, introduction of exotic plant species for commercial use has become more accessible. Such attempts may involve extreme land changes. We stress that domestication of native species should be preferred to the introduction of exotic species. We took the initial steps in domesticating several species by examining commercial uses and studying aspects of plant physiology. The following desert plants were considered: Bassia indica, for salt phytoremediation and for livestock feed; Commiphora gileadensis, as an agent against cancer cells; Artemisia sieberi and A. judaica, as plants with allopathic traits; Ficus palmate, as a stand for fig plantation; Balanites aegyptiaca, as a medicinal plant and for other uses; Portulaca oleracea and Scorzonera judaica, as food crops with added values; and Pistacia atlantica, as rootstock for P. vera. 相似文献
126.
Per Wallgren Inger Marit Brunborg Gunilla Blomqvist Gunnar Bergstr?m Frida Wikstr?m Gordon Allan Caroline Fossum Christine Monceyron Jonassen 《Acta veterinaria Scandinavica》2009,51(1):13
Background
Postweaning Multisystemic Wasting Syndrome (PMWS) is an emerging disease in pigs of multifactorial origin, but associated to porcine circovirus type 2 (PCV2) infection. PMWS was first diagnosed in Sweden at a progeny test station that received pigs aged five weeks from 19 different nucleus herds on the day after weaning. The objective of this study was to examine, for the first time in an index outbreak of PMWS, the relationship between PCV2 virus, antibodies to PCV2 and serum amyloid a (SAA) in sequentially collected serum samples from pigs with and without signs of PMWS.Methods
Forty pigs of the last batch that entered the station at a mean age of 37.5 days were monitored for signs of PMWS during the first 55 days after arrival. Serum was collected on six occasions and analysed for presence of PCV2 DNA and antibodies to PCV2, as well as for levels of SAA.Results
Four of the pigs (10%) were concluded to have developed PMWS, with necropsy confirmation in three of them. These pigs displayed low levels of maternal antibodies to PCV2, more than 107 PCV2 viral DNA copies per ml serum and failed to mount a serological response to the virus. Starting between day 23 and 34 after arrival, an increase in PCV2 viral load was seen in all pigs, but PCV2 did not induce any SAA-response. Pigs that remained healthy seroconverted to PCV2 as the viral load was increased, regardless of initially having low or high levels of PCV2-antibodies.Conclusion
In this index case of PMWS in Sweden, pigs affected by PMWS were not able to mount a relevant serum antibody response which contributed to the disease progression. The maximal PCV2 virus load was significantly higher and was also detected at an earlier stage in PMWS-affected pigs than in healthy pigs. However, a viral load above 107 PCV2 DNA copies per ml serum was also recorded in 18 out of 34 pigs without any clinical signs of PMWS, suggesting that these pigs were able to initiate a protective immune response to PCV2. 相似文献127.
J. H. Urdaz-Rodríguez G. T. Fosgate A. R. Alleman D. O. Rae G. A. Donovan P. Melendez 《Tropical animal health and production》2009,41(7):1439-1448
A cross-sectional study was conducted to determine individual cow seroprevalence of Anaplasma marginale in adult lactating dairy cattle of Puerto Rico (PR) and to assess the associations of farm management factors on herd seroprevalence.
Antibody activity against A. marginale was determined using the MSP-5 competitive enzyme-linked immunosorbent assay. Serum samples were obtained from 2,414 adult
lactating dairy cattle from 76 randomly selected commercial dairy farms. Herd seroprevalence ranged from 3 to 100% with an
overall individual cow seroprevalence for A. marginale of 27.4%. Factors associated with high herd seropositivity were pasture grazing as the main feed source (OR = 6.5, 95% CI = 1.2–34),
observed monkeys on the premises (OR = 13, 95% CI = 1.2–138), use of 11% permethrin (OR = 17, 95% CI = 2.2–129), farmers who
attended an acaricide certification program (OR = 0.18, 95% CI = 0.04–0.74), and lack of a fly control program (OR = 5.6,
95% CI = 1.3–24). 相似文献
128.
J. H. Urdaz-Rodríguez G. T. Fosgate S. D. Waghela A. R. Alleman D. O. Rae G. A. Donovan P. Melendez 《Tropical animal health and production》2009,41(7):1465-1473
A cross-sectional study was conducted to determine individual cow seroprevalence of Babesia bovis in adult lactating dairy cattle of Puerto Rico (PR), to assess the associations of farm management factors on herd seroprevalence,
and to document the species of ticks infesting cattle within these farms. Antibody activity against B. bovis was determined using an indirect fluorescent antibody test (IFAT). Serum samples were obtained from 2,414 adult lactating
dairy cattle from 76 randomly selected commercial dairy farms. Herd seroprevalence ranged from 0 to 51% with an overall individual
cow seroprevalence for B. bovis of 26%. Ticks were collected from animals on 7 (9%) of the 76 participating commercial dairy farms. All collected ticks (n = 87)
were Rhipicephalus (Boophilus) microplus. Factors associated with high herd seropositivity were dairy farms with calf but not heifer raising facilities (OR = 16, 95%
CI = 3.0-86), having more than 4 neighbors with cattle (OR = 17, 95% CI = 1.6-178), same producer owning more than one farm
(OR = 7.2, 95% CI = 1.6-32), and use of government services to apply amitraz on cattle (OR = 5.5, 95% CI = 1.5-20). 相似文献
129.
Eduardo Antônio Sanches Giovano Neumann César Pereira Rebechi de Toledo Robie Allan Bombardelli Pitágoras Augusto Piana Elizabeth Romagosa 《Aquaculture Research》2013,44(4):534-541
The aim of this work was to evaluate the spermatic parameters of jundia, Rhamdia quelen, semen stored for short periods under different temperatures. Fifteen males were used in a time factorial experimental design (13 × 3 × 3 × 3). The sperm was stored at: 15; 25 and 35°C and activated in water at: 15; 25 and 35°C each, respectively, within storage periods of: 0; 2; 4; 6; 8; 10; 12; 16; 20; 24; 32; 40 and 48 h after collection. The treatments were performed in triplicates and in sequential protocols every 50 h. The motility parameters were evaluated using Pearson's correlation analysis and the significant parameters (P < 0.05) were summarized using principal component analysis forming two predicted groups. Group 01 composed the following parameters: curvilinear velocity, wobble and linearity; group 02 comprised average path velocity, straight line velocity, beating cross frequency and motility rate. Effects (P < 0.05) of treatments were observed only in group 02, with interaction between time and temperature of exposure and between exposure time and water temperature. Superior results of spermatic parameters of group 02 were observed right after collection. However, the exposure and spermatic activation at 15°C assured significant results 48 h after collection when compared with 25 and 35°C. 相似文献
130.
Allan J. Williamson Joao H.N. Soares Noah D. Pavlisko Robert McAlister Council-Troche Natalia Henao-Guerrero 《Veterinary anaesthesia and analgesia》2017,44(4):738-745