A field study was conducted in Brazil to evaluate the efficacy of single vaccination of pigs with two bacterins to prevent Mycoplasma hyopneumoniae lung lesions. The first (T1) treatment group (174 pigs) was injected with 2 mL of saline solution; group T2 (177 pigs) with 2 mL of bacterin A, and group T3 (174 pigs) with 2 mL of bacterin B. On days-on-test (DOT) 0, 35, 66, 97 and 125, blood samples and tonsil swabs were collected from selected pigs for antibody determination (indirect ELISA) and PCR assay for the presence of M. hyopneumoniae. Pigs were slaughtered on DOT 126-129 and lung lesions were scored blindly. Bacterin A vaccinated pigs had significantly (P < or = 0.05) lower lung lesion scores (0.2%) than bacterin B (0.4%) or saline-treated pigs (1.2%); there was also a significantly lower (P < or = 0.05) number of pigs with lung lesions (27.1%), than bacterin B (38.2%) or saline-treated (55.4%) pigs. The two vaccines had similar (P>0.05) results in terms of mean weight gain, average daily weight gain, feed efficiency, frequency of PCR positives, and there was similar antibody conversion (ELISA). It was concluded that although the productivity parameters and antibody conversions were similar, bacterin A was more effective in preventing and reducing the severity of lung lesions than bacterin B. 相似文献
Leptospirosis is a systemic disease of humans and domestic animals, mainly dogs, cattle and swine. The course of human leptospirosis varies from mild to severe fatal forms and the most severe form of human leptospirosis is principally caused by Leptospira interrogans serovar icterohaemorrhagiae (L. icterohaemorrhagiae). The enzyme adenosine deaminase (ADA) plays an important role in the production and differentiation of blood cells. The aim of this study was to evaluate the activity of ADA in serum, erythrocytes and lymphocytes of rats infected with L. icterohaemorrhagiae, as compared with non-infected rats. Twenty-four adult rats, divided into two uniform groups (A and B) were used for the enzymatic assays. The animals in Group B were inoculated intraperitoneally with 2×10(8) leptospires/rat, and the rodents in Group A (control) were not-inoculated. Blood collection was performed on days 5 and 15 post-infection (PI) and the blood used to assess the ADA activity. The infection by L.icterohaemorrhagiae altered erythrocyte count, hemoglobin concentration and hematocrit, causing a decrease in all these parameters on day 15 PI. Lymphocytes decreased significantly on day 15 PI, and ADA activity in serum was inhibited in infected rats on days 5 and 15 PI and its activity in erythrocytes were increased on day 5 PI. On day 5 PI, we found an increase in ADA activity in erythrocytes of infected rats. No correlation was observed between hematocrit and erythrocyte ADA activity on days 5 and 15 PI. The ADA activity was inhibited in rats infected on day 15 PI. A positive correlation (r(2)=60) was also observed between the number of lymphocytes and ADA activity in lymphocytes on day 15 PI (P<0.05). In conclusion, our results showed that the ADA activity is altered in serum, lymphocytes and erythrocytes in experimental infection by L.icterohaemorrhagiae in rats, concomitantly with hematological parameters. 相似文献
Consumption of fresh apple fruits can induce allergic reactions in humans. The apple allergen Mal?d?1 is responsible for these allergic reactions in humans in Central Europe and North America. Biosynthesis of Mal?d?1 depends on apple cultivar, and its concentration increases with time during fruit storage. However, data on the impact of different fruit storage conditions during long-term storage are scarce. Hence, the Mal?d?1 contents of eight apple cultivars were analyzed for this study during long-term storage in a cold chamber as well as under controlled atmosphere conditions (CA). After harvest, apple fruits were stored for 12, 20, 28 or 36 weeks in a cold-chamber at +?2?°C or as under controlled atmosphere conditions of 1.5?% CO2, 1.5?% O2 at +?2?°C. Mal?d?1 content in apple fruit of all eight cultivars examined increased during fruit storage. In most cases, differences between Mal?d?1 of apple fruits stored in the cold chamber and under CA conditions were significant, but inconsistent. In apple cv. ??Elise??, fruits stored in the cold chamber contained more Mal?d?1 compared with those stored in CA, whereas the situation reversed in other varieties like cv. ??Boskoop??. The greatest Mal?d?1 content was measured in fruits of cvs. ??Golden Delicious?? and ??Gala??, whereas the smallest Mal?d?1 level was in cvs. ??Elise?? and ??Pinova?? over the whole storage time. Overall, this experiment showed the complexity of the relationship between the Mal?d?1 content, allergenicity of apple fruits, different cultivars, storage conditions and storage time. Persons allergic to apple fruits should consume the fruits as fresh as possible or only after a limited storage time. Furthermore, they should prefer apple varieties with a low content of allergenic proteins, such as cv. ??Elise?? or cv. ??Boskoop?? as a cultivar known for its large polyphenol content. 相似文献
This study aimed to evaluate the effects of a constant rate infusion (CRI) of xylazine or xylazine in combination with lidocaine on nociception, sedation, and physiologic values in horses. Six horses were given intravenous (IV) administration of a loading dose (LD) of 0.55 mg/kg of xylazine followed by a CRI of 1.1 mg/kg/hr. The horses were randomly assigned to receive three treatments, on different occasions, administered 10 minutes after initiation of the xylazine CRI, as follows: control, physiologic saline; lidocaine low CRI (LLCRI), lidocaine (LD: 1.3 mg/kg, CRI: 0.025 mg/kg/min); and lidocaine high CRI (LHCRI), lidocaine (LD: 1.3 mg/kg, CRI: 0.05 mg/kg/min). A blinded observer assessed objective and subjective data for 50 minutes during the CRIs. In all treatments, heart and respiratory rates decreased, end-tidal carbon dioxide concentration increased, and moderate to intense sedation was observed, but no significant treatment effect was detected in these variables. Ataxia was significantly higher in LHCRI than in the control treatment at 20 minutes of infusion. Compared with baseline values, nociceptive threshold increased to as much as 79% in the control, 190% in LLCRI, and 158% in LHCRI. Nociceptive threshold was significantly higher in LLCRI (at 10 and 50 minutes) and in LHCRI (at 30 minutes) than in the control treatment. The combination of CRIs of lidocaine with xylazine produced greater increases in nociceptive threshold compared with xylazine alone. The effects of xylazine on sedation and cardiorespiratory variables were not enhanced by the coadministration of lidocaine. The potential to increase ataxia may contraindicate the clinical use of LHCRI, in combination with xylazine, in standing horses. 相似文献
The effects of epidural and intravenous (IV) methadone (0.5mg/kg) on the minimum alveolar concentration of isoflurane (ISO(MAC)) were compared in dogs. Six dogs (16.5 ± 2.5 kg bodyweight) received three treatments in random order during isoflurane anaesthesia, with a 7 day washout interval between each study. Methadone was injected via a lumbosacral epidural catheter introduced 10 cm cranially into the epidural canal and the electrical stimulation for ISO(MAC) determination was applied either to the thoracic (EP(T) treatment) or to the pelvic limb (EP(P) treatment) during separate study days. In the IV treatment, ISO(MAC) was determined via electrical stimulation of the pelvic limb. Variables were recorded before (baseline), 2.5 and 5h after drug injection. The ISO(MAC) decreased significantly (P<0.05) from baseline at 2.5 and 5h after methadone in all treatments. At 2.5h, the magnitude of ISO(MAC) reduction did not differ between treatments (mean decreases from baseline: 30-33%). The ISO(MAC) reduction lasted longer following epidural methadone in the thoracic limb (decreases from baseline: 30% at 5h in the EP(T) treatment vs. 19% and 16% in the EP(P) and IV treatments, respectively). Although the isoflurane sparing effect provided by epidural methadone was not significantly greater than IV methadone during the initial stage (2.5h), it was more prolonged than the IV route in specific dermatomes (5h in the thoracic limb) with the epidural technique employed. Methadone may therefore provide a greater isoflurane sparing effect when administered epidurally, compared to IV, when noxious stimulation occurs in specific dermatomes. 相似文献
The evaluation of changes in litter decomposition rate due to increasing trend in tropospheric ozone is an emerging field of investigation, providing relevant information on long-term forest ecosystem sustainability.
Aims
This research aims to clarify the effects of ozone exposure on Quercus ilex leaf chemical composition and decomposition slow down.
Methods
Young plants were fumigated in growth chambers at a cumulative dose of 17.15 ppm h. To assess the fumigation effectiveness, stomatal conductance and net photosynthesis were monitored. Leaves were analysed for C, N, S, Ca, Mg, K, Fe, Zn, Mn, total soluble sugars, starch, acid-detergent fibre (ADF), lignin and cellulose prior to the incubation in litter bags in mesocosms, and during decomposition along 395 days.
Results
Ozone-exposed leaves showed a significant reduction in net photosynthesis and stomatal conductance but did not differ from control leaves in all the chemical parameters analysed. Nevertheless, leaf decomposition rate was lower in treated leaves. The main differences between the models describing the mass loss in exposed and control leaves were played by ADF for exposed leaves and by lignin for control leaves, as well as by N, that showed a greater contribution in the model for the exposed leaves.
Conclusion
Ozone fumigation of Q. ilex results in leaf litter decomposition slowing down, mainly due to ADF joint dynamics with the other variables describing mass decay, even if no detectable changes in initial leaf composition occur. 相似文献
Serum protein electrophoresis (SPE) is a technique that could be considered one of the most useful diagnostic aids available to the clinician. The effect of storage time and temperature on the total proteins and electrophoretic fractions (albumin, α1-, α2-, β1-, β2-, and γ-globulins) was assessed in 24 healthy horses. All samples, collected by jugular vein puncture, were centrifuged and divided into 4 aliquots. The 1st aliquot was analyzed within 3 h from collection (time 0), the 2nd was refrigerated at +4°C for 24 h, the 3rd was refrigerated at +4°C for 48 h, and the last was frozen at −20°C for 48 h. One-way repeated-measures analysis of variance (ANOVA) showed a significant effect (P < 0.05) of the different storage conditions on the concentrations of all the parameters studied and significant variations in the percentages of albumin, α1-globulins, α2-globulins, and γ-globulins. Compared with time 0 the total protein concentration increased significantly after 48 h at −20°C, the albumin percentage decreased after 48 h at −20°C, the α1-globulin percentage increased after 24 h at +4°C, the α2-globulin percentage increased after 48 h at +4°C and at −20°C, and the γ-globulin percentage increased after 48 h at −20°C. The results should help veterinary practitioners handle and store equine serum samples appropriately. Further investigations at different storage times and temperatures could be useful. 相似文献
Methods based on RGB (Red, Green, Blue) image segmentation may emerge as a new and low-cost method for estimation the quality of tree seedlings. However, the vast number of indexes based on the use of the RGB image segmentation and the lack of references in the literature still hinder the widespread use of this technology. Thus, we conducted a study aiming to test the relationships between methods based on absorbance and reflectance, widely used for the estimation of chlorophyll contents and physiological status of trees, and ten indexes based on RGB component analysis. We used leaves of five tropical tree species, belonging to different botanical families. Leaf absorbance was measured using the handheld chlorophyll meter SPAD-502, reflectance was measured using a spectrometer and the RGB indices were obtained from digitalized images of the leaves using a flatbed scanner. Modified linear regression models including all five species were used to relate RGB indices to absorbance and reflectance indices. Data collected from leaves of seedlings of five tropical tree species indicated that digital image processing technology can be a useful and rapid nondestructive method for assessment of physiological status of tree seedlings at nursery stage. Among the RGB indexes tested in this study the R, 2R*(G???B)/(G?+?B) and 2G*(G???B)/(G?+?B) are the most promising for analysis the tropical seedlings physiological status and quality.
Agricultural herbicides are among the most commonly used pesticides worldwide, posing serious concerns for both humans, exposed to these chemicals through many routes, and the environment. To clarify the effects of three herbicides as commercial formulations (namely, Pointer, Silglif, and Proper Energy), parameters related to oxidative issues were investigated on an autochthonous wine yeast strain. It was demonstrated that herbicides were able to affect the enzymatic activities of catalase and superoxide dismutase, as well as to induce carbonylation and thiol oxidation as post-translational modifications of proteins. Saccharomyces cerevisiae is an optimal model system to study responses to xenobiotics and oxidative stress. Thus, the results obtained could further the understanding of mechanisms underlying the toxicity of herbicides. 相似文献