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排序方式: 共有365条查询结果,搜索用时 15 毫秒
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2.
Filipe?Selau?CarlosEmail author Bruno?Loss?dos?Santos Robson?Andreazza Marino?José?Tedesco Lawrence?Morris Flávio?Anastácio?de?Oliveira Camargo 《Paddy and Water Environment》2017,15(1):133-144
Treated industrial effluents have high levels of nutrients and dissolved organic matter. The irrigation of rice by flooding can increase nutrient uptake and grain yield. Therefore, this study evaluated the nutrient contents in the shoots and grain of the rice crop and also the chemical of the soil after irrigation of the crop with leachate of the treated industrial effluent. A greenhouse experiment was conducted using pots filled with 20 kg of soil in a randomized block design with three replications. The treatments consisted of control (irrigation with distilled water) and four concentrations of the leachate (25, 50, 75, and 100 %) for irrigation. At the end of the experiment, the nutrient contents in tissues of rice plants, sterility of spikelets, and grain mass were evaluated. Results showed that irrigation with the leachate at 25 % content increased the macro- and micronutrients’ concentrations in the shoot biomass and grain, except for potassium and iron. Irrigation with the industrial leachate decreased tillering and grain yield; however, it increased chlorophyll content, sterility of spikelets, and sodium intake at this leachate concentration. The potassium and sodium levels and the electrical conductivity values of soils irrigated with treated industrial leachate were increased. The use of the treated leachate from industrial effluents is an alternative that reuses the nutritional load, but the volume of leachate should be limited and monitored to prevent the sodicity in the soil and problemsdue to eutrophication. 相似文献
3.
Puccio M Marino DJ Stefanacci JD McKenna B 《Journal of the American Animal Hospital Association》2003,39(5):473-478
A retrospective study was performed describing the clinical presentations, radiographic findings, and surgical outcomes of 17 dogs (18 elbows) following medial coronoidectomy for the treatment of elbow joint incongruity as a sole disease entity. Complete resolution of lameness was achieved in 100% of the cases. The mean radiographic arthrosis grade progressed in 70% of the cases. Results of this study indicate that resolution of clinical lameness may be achieved with medial coronoidectomy in dogs with elbow incongruity; however, progression of degenerative joint disease with unknown, long-term clinical significance can be expected after surgery. 相似文献
4.
Sevi A Albenzio M Annicchiarico G Caroprese M Marino R Taibi L 《Journal of animal science》2002,80(9):2349-2361
A 6-wk trial was performed with thirty-six lactating Comisana ewes during the summer of 2001. The animals were divided into three groups of 12, which were designated low (LVR), moderate (MVR), and programmed (PROGR) ventilation regimens. In LVR and MVR rooms, fans provided 10 ventilation cycles of 12.5 and 25 min/h, respectively, whereas in the PROGR room, the fan was programmed to operate at 30 degrees C air temperature and 70% relative humidity. Mean ventilation rates were 33, 66, and 173 m3/h per ewe in LVR, MVR, and PROGR rooms. Air concentrations of microorganisms and dust and of gaseous pollutants were measured twice weekly. Respiration rate and rectal temperature were monitored throughout the trial at 1430. Behavioral traits of ewes were recorded once per week from 0930 to 1230. Cell-mediated immune response to phytohemagglutinin at d 3, 20, and 40 and humoral response to chicken egg albumin at d 11, 21, 30, and 40 were determined. At d 37, ewes were injected with 2 IU porcine ACTH/kg body weight(0.75) and subjected to blood sampling for evaluation of cortisol concentrations immediately before and 1, 2, and 4 h after ACTH injection. Milk yield was recorded daily. Individual milk samples were analyzed weekly for composition and renneting parameters and fortnightly for bacteriological characteristics. Averages of temperature-humidity index values were 78.9, 76.8, and 74.5 in LVR, MVR, and PROGR rooms, respectively. The LVR and MVR treatments resulted in higher NH3 and CO2 air concentrations than PROGR treatment (P < 0.05). The LVR and MVR ewes had higher rectal temperatures than PROGR ewes (P = 0.001). LVR animals also exhibited higher idling compared to PROGR (P < 0.01) and lower feeding times than MVR (P < 0.05) and PROGR animals (P < 0.01). Ewes under the LVR treatment displayed significant lower averages of antibody titers and higher plasma cortisol levels than PROGR (P < 0.01) and MVR ewes (P < 0.05) 60 min after ACTH injection. The LVR treatment resulted in lower yields of milk (P < 0.01) and reduced feed efficiency (P < 0.01) than PROGR treatment. Results suggest that a fan-ventilated system, providing ventilation cycles during the warmest hours of the day and the night at a mean ventilation rate of 66 m3/ewe per hour, may sustain the performance and welfare in lactating ewes raised in warm climates during summer. A ventilation regimen, programmed to operate over upper critical air temperature and relative humidity, may be economically unattractive under these conditions. 相似文献
5.
Alessandra Torina Victoria Naranjo Maria Grazia Pennisi Tatiana Patania Fabrizio Vitale Pietro Laricchiuta Angelina Alongi Salvatore Scimeca Katherine M Kocan José de la Fuente 《Journal of zoo and wildlife medicine》2007,38(4):591-593
Lions (Panthera leo) are an endangered species threatened by illegal hunting, habitat loss, and infectious diseases. Little is known about the tick-borne pathogens that infect lions and could contribute to population declines. The objective of this study was to characterize Rickettsia spp., Anaplasma phagocytophilum, and Coxiella burnetii infections in 10 lions from the Fasano Safari Park in Italy by serology, polymerase chain reaction, and sequence analysis. Although animals did not show clinical signs of tick-borne diseases, evidence of infection with C. burnetii, spotted fever group Rickettsia sp., and A. phagocytophilum were found in 50%, 20%, and 10% of the lions, respectively. One of the lions tested positive for all three pathogens. This study is the first report of molecular evidence of infection with C. burnetii, Rickettsia sp., and A. phagocytophilum in lions and provides evidence that these felids become infected and serve as hosts for tick-transmitted bacteria. 相似文献
6.
G. La Rosa M. Muscillo A. Di Grazia S. Fontana M. Iaconelli M. Tollis 《Zoonoses and public health》2006,53(6):257-265
Porcine enteroviruses (PEVs) and teschoviruses (PTVs) are described as causative agents of neurological disorders, fertility disorders and dermal lesions of swine. Difficulties in the serological detection of these viruses may lead to a significant underestimation of infections with clinical symptoms. With the recent availability of genome sequence data for all the serotypes, molecular diagnosis is a possibility. The present study describes a new approach to molecular ‘serotyping’ of PTVs and PEV‐B viruses, involving the amplification and sequencing of a genomic fragment of the VP1 coding region. A molecular characterization of Italian entero‐teschovirus isolates was performed using a set of previously published and newly designed polymerase chain reaction primers. A total of 33 porcine isolates and 10 reference strains were analysed. Porcine enterovirus‐B samples were first diagnosed as positive for enterovirus by amplification of the 5′‐non‐translated region. Samples were then typed by amplification and sequencing of a portion of the VP1 coding region. Porcine enterovirus‐A and PTVs were detected by a published assay in the 5′‐NC region that allows them to be differentiated according to the size of amplification product, using the same set of primers. For serotype characterization of PTV, we evaluated four different regions: the N terminus of the capsid protein VP2, the region encoding for RNA‐dependent RNA polymerase, and the capsid VP1 and VP4 regions. The newly designed primers in the VP1 region was proved to be broad in range and suitable for serotype assessment and therefore constitute a useful diagnostic tool for molecular diagnosis of porcine teschovirus/enterovirus strains and for the study of molecular epidemiology and evolution of these viruses. 相似文献
7.
By C. Hagger 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2000,117(1):57-64
Fixed effects of age at first litter and of season of lambing as well as variance components for additive genetic, flock × year and sire of litter effects on size of first litter were estimated for an animal model by a derivative-free REML procedure. Data of the four Swiss sheep breeds White Alpine (WAS), Brown-headed Meat (BFS), Black-Brown Mountain (SBS) and Valais Black Nose (SN) were available. Number of first litters used were 21 384, 21 607, 15 013, 12 394 and 18 110 the WAS (two data sets, WAS1, WAS2), BFS, SBS and SN, respectively. Litter size of ewes lambing the first time at 2 years of age was 0.27, 0.31, 0.41, 0.46 and 0.26 lambs larger than of ewes lambing the first time at 1 year of age. The largest increase occurred for the two breeds (BFS, SBS) with the lowest average age at first litter. The largest difference between any two lambing seasons within breed were 0.16, 0.16, 0.29, 0.22 and 0.07 lambs. Estimates of additive genetic variance of size of first litter were between 0.0269 (SN) and 0.0765 (SBS). Heritability estimates for this trait were 0.171, 0.156, 0.114, 0.225 and 0.122 for WAS1, WAS2, BFS, SBS and SN, respectively. A large flock × year component (relative to phenotypic variance) of 0.148 was found for SN, compared with estimates between 0.042 and 0.067 for the other breeds. A sire of litter component (relative to phenotypic variance) of 0.066 was found for SN, compared with estimates between 0.016 and 0.039 for the other breeds. It can be concluded that all nongenetic effects investigated should be taken into account for the estimation of additive genetic variance and breeding values for size of first litter, and that considerable variation in size of genetic and nongenetic effects exists in the sheep breeds under consideration. 相似文献
8.
By K. Ruhland W. Gränzer W. Groth† F. Pirchner 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》1999,116(5):415-423
High-altitude grazing, at or above the timberline in summer months continues to be important in alpine regions of Europe, where about 80% of young stock spend much of the three summer months on these pastures. Apart from direct utilization of these resources and saving of feed in the home farms, alped cattle are said to have greater longevity and better growth, i.e. they display compensatory growth. K& uuml ; nzi et al. (1988), S uttner (1980) and R uhland (1983) reported that heifers which spent one or two summers on alpine pastures, have, as cows in intra-herd comparisons, about one lactation more than homegrown heifers. Compensatory growth after alpage was reported by these authors, by B ianca (1977), W eilenmann -B ossart (1988) and other authors. The effects of alpine sojourn on physiological and biochemical traits were investigated by B ianca and E spinosa (1975), B ossart et al. (loc. cit.), K rippl et al. (1961) and S uttner (1980). This investigation concerns the comparative effects of alpine pasture and farm feeding on subsequent physiological and biochemical traits. 相似文献
9.
A technique for determining the ergosterol content in mycorrhizal pine roots using HPLC was developed. Pure cultures of different my corrhizal fungi contained very similar and constant amounts of ergosterol, and calculations of fungal biomass in mycorrhizal roots based on ergosterol readings agreed well with results using other methods. The extraction and sample purification were simple and reliable. Consequently, the technique is considered practical wherever accurate estimates of the intensity of mycorrhizal infection are required. 相似文献
10.
Inmaculada Moreno Julio Álvarez Nerea García Santiago de la Fuente Irene Martínez Eloy Marino Alfredo Toraño Joaquin Goyache Felipe Vilas Lucas Domínguez Mercedes Domínguez 《Veterinary parasitology》2014,199(3-4):264-267
An outbreak of human leishmaniosis was confirmed in the southwest of the province of Madrid, Spain, between July 2009 and December 2012. Incidence of Leishmania infection in dogs was unchanged in this period, prompting a search for alternative sylvatic infection reservoirs. We evaluated exposure to Leishmania in serum samples from animals in the area with an indirect immunofluorescence test (IFAT). Using promastigotes from six culture passages and a 1/25 threshold titer, we found anti-Leishmania infantum seroreactivity in 9.3% of cats (4 of 43), 45.7% of rabbits (16/35) and 74.1% of hares (63/85). Use of promastigotes from >10 in vitro passages resulted in a notably IFAT lower titer, suggesting antigenic changes during extended culture. Postmortem inspection of seropositive animals showed no clinical signs of infection. The results clearly suggest that asymptomatic hares were the main reservoir in the outbreak, and corroborate IFAT as a sensitive serological surveillance method to detect such cryptic Leishmania infections. 相似文献