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921.
Otranto D Llazari A Testini G Traversa D Frangipane di Regalbono A Badan M Capelli G 《Veterinary parasitology》2003,118(1-2):7-18
A cross-sectional serological survey for Neospora caninum was carried out on beef and dairy cattle in southern and northern Italy. A total of 111 herds and 1140 animals were tested using an ELISA assay (CHEKIT-Neospora) to detect anti-N. caninum antibodies. Management and individual data were collected and analysed both by linear and logistic multiple-regression models in order to find good predictors of the cattle seroprevalence and anti-N. caninum antibody level. At least one seropositive animal was found in 49 herds (44.1%), of which 31 (39.7%) from southern Italy and 18 (54.5%) from northern Italy. A total of 126 head of cattle (11%) were found to be seropositive and the seroprevalence was lower in southern (8.7%) than in northern Italy (16%). One of the best predictors of neosporosis seroprevalence in this study was the practice of self-rearing replacement heifers. Further risk factors were linked to higher stocking density, i.e. animals farmed in large herds and with no summer or permanent grazing practices were more likely to be seropositive than others. Farms with two or more dogs had higher herd seropositivity than farms with one or no dogs and this factor interacted significantly with the farm size and presence of poultry. Among individual characteristics, seropositivity was higher in animals sampled in mid- or late-pregnancy compared to animals either in early pregnancy or not pregnant. There was a significant interaction between the factors for pregnancy status and grazing practices. None of the epidemiological data recorded was a good predictor of the anti-N. caninum antibody level. 相似文献
922.
The present report addresses the development of cutaneous and ocular reactions possibly related to meloxicam administration in a dog. Based on clinical signs and absence of laboratory data compatible with the other differential diagnoses considered, the possibility of an adverse drug reaction (ADR) due to meloxicam was considered. Skin biopsy revealed haemorrhage of the superficial and deep dermis, associated with hyperplasia of endothelial cells and epidermal sloughing. Vasculitis in the deep dermis was also noted. Such lesions were considered compatible with an ADR. Although the owner was not aware of any previous allergic reaction to drugs, the animal had a clinical history of atopic dermatitis. Meloxicam is a nonsteroid anti-inflammatory drug (NSAID) in the oxicam family, indicated for the control of inflammation and pain in acute and chronic musculoskeletal disorders in dogs. Although meloxicam is usually well tolerated, the present clinical case represents an alert to practitioners about the potential role of NSAIDS in ADRs in dogs with a history of allergic cutaneous diseases. 相似文献
923.
Garcia MV Monteiro AC Szabó MP Mochi DA Simi LD Carvalho WM Tsuruta SA Barbosa JC 《Veterinary parasitology》2011,181(2-4):267-273
This work aimed to assess the effect of the fungus Metarhizium anisopliae on off-host Rhipicephalus (Boophilus) microplus from tick-infested Brachiaria decumbens pasture undergoing cattle grazing. For this purpose a naturally tick-infested Brachiaria decumbens pasture of 60 m × 100 m with twelve grazing Holstein Friesian-Nelore (Bos indicus) cross breed bovines was sprayed 12 times, 21 days apart with an aqueous conidial suspension of the E9 isolate of M. anisopliae fungus. Control pasture was treated with conidial suspension vehicle only. Efficacy of treatment was evaluated by tick larvae counts on the pasture and that of engorged female ticks on grazing cattle. Fungus persistence on grass stems as well as soil pasture was assessed after each spray. Efficacy of fungus against ticks was also measured by an in vitro immersion test. Whereas in vitro test showed a clear pathogenic effect of the fungus on ticks, no pathogenic effect over R. (B.) microplus ticks was detected in the field trial by spraying pasture with fungal suspension. Fungus from the suspension could be recovered from both the grass stem as well as the soil of sprayed pasture, even though the numbers obtained varied distinctly and could only be recovered shortly after spray. Pasture environments with exposure to sun and rain, seem to be very detrimental to the fungus, thus suspensions which provide fungus with protection or more resistant isolates to these should be looked for. In order to achieve high fungal efficacy against tick under field conditions, accurate laboratory assays, optimization of application strategy and knowledge of interactions between fungal strains and environmental factors are warranted. 相似文献
924.
Arráez-Román D Segura-Carretero A Cruces-Blanco C Fernández-Gutiérrez A 《Pest management science》2004,60(7):675-679
This paper describes a UV detection method for the pesticides aldicarb and carbofuran, and some of their main metabolites, aldicarb-sulfoxide, aldicarb-sulfone and 3-hydroxy-carbofuran, in ground waters. Micellar electrokinetic chromatography (MEKC) with diode-array detection was developed for their determination at 210 nm. The experimental study was performed using sodium dodecyl sulfate (SDS) at a concentration level of 140 mM, and a buffer of borax/HCl 20 mM at pH 8 which gives the best resolution with an analysis time of less than 20 min. Different instrumental parameters such as voltage (23 kV), injection time (12 s) and temperature (25 degrees C) were optimized. The detection limits were in the range 2-7.4 microg glitre(-1) by solid-phase extraction (SPE) with a subsequent evaporation step. Groundwater spiked samples were pre-concentrated off-line with graphite carbon and subsequently analyzed by MEKC with diode-array detection yielding average recoveries between 77 and 97% (n = 4) with RSD between 2-7%. 相似文献
925.
Jorge F. Toro-Vazquez Carlos A. Gmez-Aldapa Antonio Aragon-Pia Edmundo Brito-de la Fuente Elena Dibildox-Alvarado Miriam Char-Alonso 《Journal of Cereal Science》2003,38(3):269-279
In this study we evaluated the thermo-mechanical properties of maize starch pastes (80% wt/wt) under the effect of exogenous lysophosphatidylcholine (LPC) using differential scanning calorimetry (DSC), dynamic mechanical spectrometry (DMS), and scanning electron microscopy (SEM). Particular attention was paid to the development of the amylose-LPC inclusion complex. Results from SEM and DSC showed that with no exogenous LPC, granular maize starch developed the amylose network structure for starch gelling at 80–95 °C. In comparison, at 1.86 and 3.35% of LPC, heating up to 130 °C was needed to develop the three-dimensional network required for starch gelling. Results showed that at these LPC concentrations LPC interacted mainly with amylose within the starch granule. At concentrations ≥8.26% the LPC interacted with amylose both inside the granule and on the granule's surface. At such LPC concentrations heating to 130 °C did not fully develop the starch network structure for gelling. These results suggested that a higher thermal stability was achieved by starch granules because of LPC inclusion complex formation. DSC or DMS did not detect the development of this complex, probably because its formation took place below the onset of gelatinization under conditions of limited molecular mobility. Subsequently, a lower level of organization (i.e. complex in form I) was achieved than in the complex developed at high temperature and water excess (i.e. complex in form II). On the other hand, the changes in the starch granule structure observed by SEM as a function of the time–temperature variable were well described by the phase shift angle (δ) rheograms for starch pastes with and without addition of LPC. 相似文献
926.
Landaeta-Hernández Antonio J. Ungerfeld Rodolfo Randles Ronald Littell Ramon Rae D. Owen Chenoweth Peter J. 《Tropical animal health and production》2020,52(2):743-751
Tropical Animal Health and Production - The objective of this study was to assess aspects of the social behavior of a mixed-breed herd of beef cows as a potential source for stress and economic... 相似文献
927.
Humberto J. Domínguez Guillermo D. Crespín Adrián J. Santiago-Benítez José A. Gavín Manuel Norte José J. Fernández Antonio Hernández Daranas 《Marine drugs》2014,12(1):176-192
Marine organisms are an increasingly important source of novel metabolites, some of which have already inspired or become new drugs. In addition, many of these molecules show a high degree of novelty from a structural and/or pharmacological point of view. Structure determination is generally achieved by the use of a variety of spectroscopic methods, among which NMR (nuclear magnetic resonance) plays a major role and determination of the stereochemical relationships within every new molecule is generally the most challenging part in structural determination. In this communication, we have chosen okadaic acid as a model compound to perform a computational chemistry study to predict 1H and 13C NMR chemical shifts. The effect of two different solvents and conformation on the ability of DFT (density functional theory) calculations to predict the correct stereoisomer has been studied. 相似文献
928.
Associations between immune competence phenotype and feedlot health and productivity in Angus cattle
Brad C Hine Amy M Bell Dominic D O Niemeyer Christian J Duff Nick M Butcher Sonja Dominik Laercio R Porto-Neto Yutao Li Antonio Reverter Aaron B Ingham Ian G Colditz 《Journal of animal science》2021,99(2)
Genetic strategies aimed at improving general immune competence (IC) have the potential to reduce the incidence and severity of disease in beef production systems, with resulting benefits of improved animal health and welfare and reduced reliance on antibiotics to prevent and treat disease. Implementation of such strategies first requires that methodologies be developed to phenotype animals for IC and demonstration that these phenotypes are associated with health outcomes. We have developed a methodology to identify IC phenotypes in beef steers during the yard weaning period, which is both practical to apply on-farm and does not restrict the future sale of tested animals. In the current study, a total of 838 Angus steers, previously IC phenotyped at weaning, were categorized as low (n = 98), average (n = 653), or high (n = 88) for the IC phenotype. Detailed health and productivity data were collected on all steers during feedlot finishing, and associations between IC phenotype, health outcomes, and productivity were investigated. A favorable association between IC phenotype and number of mortalities during feedlot finishing was observed with higher mortalities recorded in low IC steers (6.1%) as compared with average (1.2%, P < 0.001) or high (0%, P = 0.018) IC steers. Disease incidence was numerically highest in low IC steers (15.3 cases/100 animals) and similar in average IC steers (10.1 cases/100 animals) and high IC steers (10.2 cases/100 animals); however, differences between groups were not significant. No significant influence of IC phenotype on average daily gain was observed, suggesting that selection for improved IC is unlikely to incur a significant penalty to production. The potential economic benefits of selecting for IC in the feedlot production environment were calculated. Health-associated costs were calculated as the sum of lost production costs, lost capital investment costs, and disease treatment costs. Based on these calculations, health-associated costs were estimated at AUS$103/head in low IC steers, AUS$25/head in average IC steers, and AUS$4/head in high IC steers, respectively. These findings suggest that selection for IC has the potential to reduce mortalities during feedlot finishing and, as a consequence, improve the health and welfare of cattle in the feedlot production environment and reduce health-associated costs incurred by feedlot operators. 相似文献
929.
Vittorio Alba Cinzia Montemurro Wilma Sabetta Antonella Pasqualone Antonio Blanco 《Scientia Horticulturae》2009,123(1):11-16
Olive (Olea europaea L.) is an important fruit species in Italy and Mediterranean basin constituted by a wide germplasm with a large number of cultivars present in all the Mediterranean area. SSRs are becoming the markers of choice for variability studies in olives as they are simple to perform, transferable, hypervariable, highly polymorphic and show a high information content.Olive genetic diversity was studied using 16 SSR markers on 30 cultivars diffused in Southern-Italy. Resolving Power (RP) and Power of Discrimination (PD) were calculated to evaluate the efficiency of the SSR markers investigated in studies of cultivars fingerprinting. Based on their high efficiency, two SSR markers, UDO43 and DCA16 were chosen to set up an identification key to distinguish the entire set of cultivars, confirming the high biodiversity of the Southern-Italian olive germplasm and the suitability of SSR markers in studies of cultivar diagnosis. 相似文献
930.
ABSTRACT The effect of different combinations of temperatures and exposure times on the mortality of Heterodera schachtii eggs was assessed in two different experiments under laboratory conditions. In the first experiment, cysts in water were exposed to 25, 35, 37.5, 40, 42.5, 45, 47.5, 50, or 52.5 degrees C for a maximum period of 2 h. In the second experiment, cysts in naturally infested soil were exposed to 25, 32.5, 35, 37.5, 40, 42.5, or 45 degrees C for a minimum period of 2 h to a maximum of 2,048 h. Viability of eggs in cysts was assessed by a hatching test in 3 mM zinc chloride solution. Viability in water was suppressed after 2-h exposure at 50 degrees C and inhibited after 1 to 2 h at 52.5 degrees C. Emergence of juveniles from cysts in soil was greater at the lower temperature x exposure time combinations and suppressed at higher combinations. Egg mortality started after exposure for 256 h at 40 degrees C, 32 h at 42.5 degrees C, and 16 h at 45 degrees C, and 81, 31, and 7 h of exposure were necessary to kill 50% of the nematode egg population at 40, 42.5, and 45 degrees C, respectively. The data fitted the models P(t) = P(0)10(-t/ (q + mT)) and P(T1) = P(T0)10(-T/(z - pt)) for m = -0.0111, q = 0.8238, z = 2.444, and p = -0.23. 相似文献