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91.
An in vivo experiment was conducted to evaluate the effects of tetracycline and zinc on pig colonization and transmission of methicillin-resistant Staphylococcus aureus (MRSA) sequence type (ST) 398. Eight piglets naturally colonized with MRSA ST398 and 8 MRSA-negative piglets of the same age and breed were assigned to three groups treated with tetracycline and zinc (Group 1), zinc (Group 2) or tetracycline alone (Group 3) and one non-treated group (Group 4), each containing two MRSA-positive and two MRSA-negative animals. Two additional non-treated control groups composed of only MRSA-positive (Group 5) and MRSA-negative (Group 6) animals were used to check for stability of MRSA carriage status. Nasal swabs and environmental wipes were collected on Days 0, 7, 14, and 21, and the occurrence of MRSA in each sample was quantified by bacteriological counts on Brilliance? MRSA agar. Significantly higher nasal MRSA counts were observed in the zinc-treated (p=0.015) and tetracycline-treated (p=0.008) animals compared to the non-treated animals. Environmental MRSA counts appeared to increase over time in Groups 1 and 2 but such an increase was not statistically significant. MRSA-negative animals housed with MRSA-positive animals became positive in all groups, whereas the carriage status of the animals in Groups 5 and 6 did not change. This study demonstrates that feed supplemented with tetracycline or zinc increases the numbers of MRSA ST398 in the nasal cavity of pigs. Transmission of MRSA from positive to negative animals housed within the same pen was not influenced by exposure to these agents. 相似文献
92.
Martelli P Ferrari L Morganti M De Angelis E Bonilauri P Guazzetti S Caleffi A Borghetti P 《Veterinary microbiology》2011,149(3-4):339-351
This study investigated the efficacy of a one-dose porcine circovirus 2 (PCV2) subunit vaccine based on the PCV2 Cap protein expressed in a baculovirus system on two different farms at which a history of porcine circovirus-associated disease (PCVD) was present. Morbidity, mortality, average daily weight gain, carcass weight, PCV2 load in serum and vaccine immunogenicity were assessed. Serology to porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae was performed. A double-blind, randomised, and controlled field trial was performed distributing 818 piglets between two treatment groups. At inclusion (weaning at 21 ± 3 days of age), 408 animals (group B) received a 2-mL intramuscular dose of Porcilis PCV(?) (vaccinated group). Controls (group A, 410 pigs) received 2 mL of the adjuvant Diluvac Forte(?) intramuscularly. Weights were recorded at inclusion and at 12 and 26 weeks of age, and the average daily weight gain (ADWG) was calculated. The carcass weights of the pigs from farm 2 were recorded at slaughter (274 days old). All dead animals (died or culled) underwent autopsy to classify them as PMWS-affected or not. At each farm, blood samples were taken from 22 pigs/group for serologic studies. A beneficial effect was found after vaccination with a single dose of a PCV2 Cap vaccine against PCVD. The vaccination reduced the mortality rate and morbidity, reduced PCV2 viremia and viral load, improved productive performances (e.g. ADWG: +70 g/day between 12 and 26 weeks of age when viremia and the specific disease occurred) as well as carcass weight at slaughter age (+4.5 kg). These effects were associated with virologic and clinical protection from the immunogenicity of the vaccine measured as activation of both a humoral and a cellular immune response. 相似文献
93.
A novel and reproducible method is described for accurately determining the molecular weight distribution by size exclusion chromatography (SEC) of whole lignocellulosic materials. This approach offers the opportunity to compare the molecular weight distributions of intact milled woods and its component fractions, lignins and holocelluloses, all from the same source, thus highlighting the potential of the technique and the contributions of the individual components to the chromatogram. The method is based on the dissolution of the ball-milled samples in the ionic liquid 1-allyl-3-methylimidazolium chloride ([amim]Cl). Under these homogeneous ionic liquid media, a derivatization reaction was performed with benzoyl chloride in the presence of pyridine. The thoroughly benzoylated wood with its associated carbohydrate and lignin components was found to be completely soluble in the THF SEC eluent with marked UV detector sensitivity. This methodology, when applied to the individually isolated holocellulose and lignin (enzymatic mild acidolysis lignin; EMAL) materials from Norway spruce ( Eucalyptus grandis ) wood and corn stover, offered a better understanding as to the possible ways the lignin and the carbohydrates may interact within these three different species. Finally, the applicability of the methodology is shown for a series of pure cellulosic samples under intense mechanical defibration conditions, offering a visualization of the molecular weight distribution changes induced during the production of nanofibrillated cellulose. 相似文献
94.
95.
Ali Ismael Choukeir Levente Kovács Luca Fruzsina Kézér Dávid Buják Zoltán Szelényi Mohamed Kamel Abdelmegeid András Gáspárdy Ottó Szenci 《Reproduction in domestic animals》2020,55(11):1535-1540
In this study, the utility of a commercial intravaginal thermometer was evaluated as an automated method for the prediction of calving in a total of 257 healthy pregnant Holstein–Friesian female cattle. The accuracy and the sensitivity of predicting calving within 48 hr before calving were also evaluated. The intravaginal temperature changes from 72 hr before and up to calving were significantly (p ≤ .001) affected by parity, season (summer vs. autumn), the time of day (8 a.m. or 8 p.m.) and the 6-hr time intervals (38.19°C: first interval 0 to 6 hr before calving vs. 38.78°C: twelfth interval 66 to 72 hr before calving), while the gender (p = .943), and the weight of the calf (p = .610), twinning (p = .300), gestation length (p = .186), foetal presentation (p = .123), dystocia (p = .197) and retention of foetal membranes (p = .253) did not affect it significantly. The sensitivity of the SMS of expecting calving within 48 hr and the positive predictive value were 62.4% and 75%, respectively, while the sensitivity and the positive predictive value for the SMS of expulsion reached 100%. It can be concluded that the investigated thermometer is not able to predict calving within 48 hr accurately; however, imminent calving can be accurately alerted. 相似文献
96.
Domenico Rongai Claudio Cerato Luca Lazzeri 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(4):613-619
This study examines the effects of a vegetable fungicide on sugar beet powdery mildew (Erysiphe betae) and cucumber powdery mildew (Erysiphe cichoracearum). The formulations consisting of a dispersion of Brassicaceae meal in vegetable or mineral oils on infected leaves of sugar beet, reared in the greenhouse, and of musk melons cultivated
under plastic tunnels, were tested in comparison to each oil taken separately. Both formulations containing Brassicaceae meals, caused 94% of conidia to be distorted while for the untreated group only 2% were distorted. Furthermore, the leaf
area infected by E. betae was 56% for untreated plants and 2.7 and 9.9% respectively, for plants treated with meal containing mineral and vegetable
oil. Vegetable oil considered separately or with Brassicaceae meals showed no phytotoxicity, while the formulations based on mineral oil showed a significantly lower fresh and dry weight
on tomato plants. The low level or absence of phytotoxicity of plants treated with vegetable oil formulations suggests that
to improve the efficacy of powdery mildew control, they could be used mixed with sulphur. The efficiency of the vegetable
formulations in the powdery mildew control observed during these trials encourages further investigation on other parasitic
fungi and foliar pathogens. 相似文献
97.
98.
An adenocarcinoma of the disseminated prostate gland with pulmonary, myocardial and renal metastases is described in a 12-year-old, neutered male European cat. Histologically, the tumour was localised in the spongy layer of the prostatic urethra and showed an epithelial alveolar pattern. Considering the anatomic, microscopic and immunohistochemical findings, the tumour was diagnosed as an adenocarcinoma of the disseminated prostate gland. To our knowledge this is the first report of adenocarcinoma of the disseminated prostate gland in a cat. 相似文献
99.
Three cats were examined because of acute dyspnoea and sudden abdominal enlargement. In all cats, radiographs revealed gastric dilatation-volvulus (GDV) and diaphragmatic hernia. Cardiovascular shock and dyspnoea were treated by intravenous fluid-therapy, oxygen administration and relief of diaphragmatic pressure by means of stomach decompression and in one case placing the patient in an inclined position. Gastric decompression was performed by needle gastrocentesis, placement of a rhino-gastric tube, or a combination of these. Diaphragmatic herniorrhaphy was performed in either case; one cat also underwent gastropexy. The immediate postoperative period resolved uneventfully and the cats were doing well at follow-up. Feline GDV is a rare event in which diaphragmatic hernia may be a predisposing factor. 相似文献
100.
Luca Fava Paola Bottoni Angela Crobe Anna Barra Caracciolo Enzo Funari 《Pest management science》2001,57(12):1135-1141
The metabolites of pesticides can contaminate groundwater and pose a risk to human health when this water is used for drinking. This paper reports the results of a laboratory study on aldicarb and its main metabolites, aldicarb sulfone and aldicarb sulfoxide. Aldicarb and its metabolites showed Koc values (6–31) which were lower than that of atrazine (55), indicating that they are very mobile in soil. They are less persistent than atrazine (DT50 = 25 days), with DT50 values from less than 1 day and up to 12 days. Aldicarb behaved as a non‐leacher, whereas its metabolites clearly showed the characteristics of leachers. Aged residue leaching experiments showed that aldicarb can occur at high concentrations in the leachate, together with its two metabolites. The leachate composition depends on the incubation time of the parent compound. Aldicarb and its metabolites can form various mixtures in groundwater on the basis of the time elapsing between the application of the insecticide and the first significant rainfall. This study confirms the characteristics of contaminants of aldicarb and especially its metabolites, as reported in the literature. © 2001 Society of Chemical Industry 相似文献