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71.
Neetu Shahi László Ardó Gyöngyvér Fazekas Elen Gócza Shivendra Kumar Norbert Rèvèsz Zsuzsanna Jakabné Sándor Zsuzsanna Molnár Galina Jeney Zsigmond Jeney 《Aquaculture International》2018,26(3):727-741
To evaluate the effect of thermal and microbial stress on the immune response of common carp (Cyprinus carpio L.), relative mRNA expression level of pro-inflammatory cytokines [tumor necrosis factor alpha (TNF-α) and interleukin (IL)-1β] and other genes related to immune or stress response [inducible nitric oxide synthase (iNOS), heat shock protein 70 (Hsp70), superoxide dismutase one (SOD1), and glucocorticoid receptor (GR)] was measured by quantitative PCR (qPCR). In addition, total protein and total immunoglobulin level in blood plasma of experimental common carp was also assayed. All the above parameters were estimated 24 h post-challenge with Gram-negative bacterium, Aeromonas hydrophila. Common carp (54.89?±?6.90 g) were initially exposed to 20 °C (control group) and 30 °C (thermal stress group) water temperature for 30 days, followed by experimental challenge with 2.29?×?108 colony forming unit/mL (CFU/mL; LD50 dose) of A. hydrophila. Exposure of fish to thermal stress and subsequently challenge with A. hydrophila significantly (P?<?0.05) increases the IL-1β mRNA expression in head kidney and spleen of common carp by ~?39.94 and ~?4.11-fold, respectively. However, TNF-α mRNA expression in spleen decreased ~?5.63-fold in control fish challenged with A. hydrophila. Thermal stress and challenge with bacterium suppresses the iNOS and GR mRNA expression in spleen of common carp. Moreover, significant (P?<?0.05) increase in total protein content of blood plasma (~?43 mg/g) was evident in fish exposed to thermal stress and challenged with A. hydrophila. In conclusion, our study highlights the importance of elevated temperature stress and microbial infection in differential regulation of expression of several immunogenes in common carp. 相似文献
72.
Ferreira SR Araújo JV Braga FR Araujo JM Carvalho RO Silva AR Frassy LN Freitas LG 《Tropical animal health and production》2011,43(3):639-642
The ovicidal effect of the nematophagous fungus Pochonia chlamydosporia on eggs of Ascaris suum was tested under laboratory conditions. A. suum eggs were plated on 2% water–agar with seven fungal isolates (Isol. 5, Isol. 31, Isol. 1, VC1, Isol. 12, Isol. 22 and VC4)
and control without fungus. After 5, 7, 10, 14, 15 and 21 days of incubation, approximately 100 eggs were removed from the
plates and classified according to the following parameters: type 1, biochemical and physiological effect without morphological
damage to the eggshell, type 2, lytic effect with morphological alteration of the eggshell and embryo and type 3, lytic effect
with morphological alteration of eggshell and embryo showing hyphal penetration and internal egg colonization. The isolates
effectively destroyed A. suum eggs and all types of effects were observed during the experiment. There was no variation in ovicidal capacity (type 3 effect)
among the isolates (p > 0.05) throughout the experiment. After 21 days, isolate 5 showed the highest percentages of type 3 effect (58.33%). The
results indicated that P. chlamydosporia (Isol. 5, Isol. 31, Isol. 1, VC1, Isol. 12, Isol. 22 and VC4) can destroy A. suum eggs and is, therefore, a potential biological control agent of nematodes. 相似文献
73.
Jemberu Dessie Solomon Melaku Firew Tegegne Kurt J. Peters 《Tropical animal health and production》2010,42(5):841-848
The experiment consisting of 7 days of digestibility and 90 days of feeding trial was conducted at Wogda (Ethiopia) to determine
the effect of supplementation of graded levels of concentrate mix (CM) on feed intake, digestibility, and body weight (BW)
change in hay-based feeding of Simada sheep. Twenty-yearling Simada sheep with a mean initial BW of 17.9 ± 0.81 kg (mean ±
SD) were used in randomized complete block design arranged into five blocks of four animals. The four dietary treatments that
consisted of hay alone (T1), hay +150 g dry matter (DM; T2, low), hay +250 g DM (T3, medium), and hay +350 g DM (T4, high)
CM were randomly assigned to each sheep within a block. The CM consisted of wheat bran (WB), noug seed (Guizotia abyssinica) meal and safflower (Carthamus tinctorius) seed meal at the ratio of (2:1:1), respectively. Supplementation with T2 and T3 increased (P < 0.001) total DM and organic matter intake than the control treatment. Overall, supplementation improved (P < 0.001) crude protein intake, digestibility, feed conversion efficiency, BW gain, and profitability compared to the control,
whereas sheep on the high than the low and medium level of supplementation performed better in these parameters among the
supplemented treatments. From the results of this study, T4 is recommended as the best level of supplementation since it resulted
in better nutrient utilization, animal performance, and profitability. 相似文献
74.
Kang-Le Lu Li-Na Wang Ding-Dong Zhang Wen-Bin Liu Wei-Na Xu 《Fish physiology and biochemistry》2017,43(1):65-76
High-fat diets may have favorable effects on growth and cost, but high-fat diets often induce excessive fat deposition, resulting in liver damage. This study aimed to identify the hepatoprotective of a Chinese herb (berberine) for blunt snout bream (Megalobrama amblycephala). Fish were fed with a normal diet (LFD, 5 % fat), high-fat diet (HFD, 15 % fat) or berberine-supplemented diets (BSD, 15 % fat with berberine 50 or 100 mg/kg level) for 8 weeks. After the feeding, histology, oxidative status and mitochondrial function of liver were assessed. The results showed that HFD caused fat accumulation, oxidative stress and apoptosis in hepatocytes of fish. Hepatocytes in HFD group appeared to be hypertrophied, with larger liver cells diameter than these of LFD group. Berberine-supplemented diets could attenuate oxidative stress and hepatocytes apoptosis. HFD induced the decreasing mitochondrial complexes activities and bulk density and surface area density. Berberine improved function of mitochondrial respiratory chain via increasing the complex activities. Moreover, the histological results showed that berberine has the potential to repair mitochondrial ultrastructural damage and elevate the density in cells. In conclusion, our study demonstrated that berberine has attenuated liver damage induced by the high fat mainly via the protection for mitochondria. 相似文献
75.
J.M. Snyder L. Lipitz K.A. Skorupski F.S. Shofer T.J. Van Winkle 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2008,22(1):172-177
Background: This study investigates the frequency, location, and clinical findings associated with 177 secondary brain tumors in dogs.
Hypothesis: Secondary intracranial neoplasia is more common than primary intracranial neoplasia in dogs during the time period studied, and hemangiosarcoma (HSA) is the most common secondary intracranial tumor.
Animals: One hundred and seventy-seven client-owned dogs presented to the Matthew J. Ryan Veterinary Hospital between 1986 and 2003.
Methods: Medical records were searched for a diagnosis of intracranial neoplasia in dogs who underwent complete postmortem examination. Of these dogs, those with a diagnosis of primary intracranial neoplasia were excluded.
Results: Of the 177 secondary brain tumors, 51 (29%) were HSAs, 44 (25%) were pituitary tumors, 21 (12%) were lymphosarcomas, and 21 (12%) were metastatic carcinomas. The average age at diagnosis was 9.6 ± 3.0 years. Most tumors were located in the cerebrum, and a mentation change was the most common presenting clinical sign. On postmortem examination, the same tumor that was in the brain was also present in the lung in 84 cases (47%), in the kidney in 62 cases (35%), and in the heart in 55 cases (31%).
Conclusions and Clinical Importance: Secondary intracranial neoplasia in dogs was more common than primary intracranial neoplasia during the time period studied. Many of these dogs had related disease in other body systems that was apparent on diagnostic tests such as thoracic radiography. 相似文献
Hypothesis: Secondary intracranial neoplasia is more common than primary intracranial neoplasia in dogs during the time period studied, and hemangiosarcoma (HSA) is the most common secondary intracranial tumor.
Animals: One hundred and seventy-seven client-owned dogs presented to the Matthew J. Ryan Veterinary Hospital between 1986 and 2003.
Methods: Medical records were searched for a diagnosis of intracranial neoplasia in dogs who underwent complete postmortem examination. Of these dogs, those with a diagnosis of primary intracranial neoplasia were excluded.
Results: Of the 177 secondary brain tumors, 51 (29%) were HSAs, 44 (25%) were pituitary tumors, 21 (12%) were lymphosarcomas, and 21 (12%) were metastatic carcinomas. The average age at diagnosis was 9.6 ± 3.0 years. Most tumors were located in the cerebrum, and a mentation change was the most common presenting clinical sign. On postmortem examination, the same tumor that was in the brain was also present in the lung in 84 cases (47%), in the kidney in 62 cases (35%), and in the heart in 55 cases (31%).
Conclusions and Clinical Importance: Secondary intracranial neoplasia in dogs was more common than primary intracranial neoplasia during the time period studied. Many of these dogs had related disease in other body systems that was apparent on diagnostic tests such as thoracic radiography. 相似文献
76.
Tomoko Suzuki Shougo Nishimura Kazuhiro Yagi Ryousuke Nakamura Yoshihiro Takikawa Yoshinori Matsuda Koji Kakutani Teruo Nonomura 《Phytoparasitica》2018,46(1):31-43
The lengths of conidiophores in fungal colonies of the melon powdery mildew pathogen Podosphaera xanthii Pollacci KMP-6 N cultured under greenhouse (natural) conditions differed markedly from those cultured in a growth chamber. We hypothesized that light wavelength was responsible for the differences in conidiophore length. In this study, we examined the effects of light-emitting diode (LED) irradiation (purple, blue, green, orange, and red light) and white light on colony development and conidiophore formation in KMP-6 N using a stereomicroscope and a high-fidelity digital microscope. Colonies on leaves were flat under greenhouse conditions and under red LED light irradiation but were stacked under growth chamber conditions and under purple, blue, green, and orange LED light irradiation. In addition, KMP-6 N formed catenated conidia comprising six conidia per conidiophore under greenhouse conditions and red light but more than seven conidia per conidiophore under growth chamber conditions and purple, blue, green, and orange light. Furthermore, almost none of the conidia on top of the conidiophores grown under blue light were fully constricted. Therefore, these fungi could not scatter their conidia and spread infection. This is the first report of the effects of LED lights on conidiophore formation in the melon powdery mildew fungus P. xanthii. The results provide insight into the mechanisms underlying the responses of conidiophores to light of specific wavelengths and conidial scatter from conidiophores of melon powdery mildew fungi. 相似文献
77.
Hideaki Endo Tadayoshi Muramatsu Goro Yoshizaki Huifeng Ren Hitoshi Ohnuki 《Fisheries Science》2012,78(2):391-398
A label-free immunosensor for detecting the oocyte maturation-inducing hormone 17, 20β-dihydroxy-4-pregnen-3-one (DHP), was
developed. A principle of the sensor system was based on differences in electrochemical activity changed by an immunoreaction
in the absence and presence of DHP. For preparation of the immunosensor, anti-DHP IgG was immobilized on an Au working electrode
modified with a self-assembled monolayer of 3-mercaptopropionic acid. The sensor was immersed into a sample solution containing
DHP. DHP was determined by cyclic voltammetry. The immunosensor showed a specific response to DHP, and the oxidation peak
current linearly decreased in the range of 7.8–500 pg ml−1 with a correlation coefficient of 0.996. The sensor system was applied to determine the DHP levels in plasma of goldfish
and was compared with the DHP levels of the same samples determined using an ELISA as the conventional method. Good correlation
was obtained between values determined using both methods in the range of 0.1–7.7 ng ml−1 (correlation coefficient 0.876). These findings suggest that the proposed label-free immunosensor can be used to analyze
DHP levels in fish plasma samples. 相似文献
78.
79.
Shima Bagherabadi Doustmorad Zafari Yousef Moradi Amirabad Joyce H. C. Woudenberg 《Journal of General Plant Pathology》2017,83(6):398-401
Drimia maritima (squill) is a historically important medicinal plant. During the spring of 2016, small, yellow leaf spots, which became brown and finally necrotic, were observed on squill plants in Kohgiluyeh and Boyer-Ahmad Provinces in Iran. A fungus was consistently isolated from infected leaves and identified as Alternaria alternata based on morphological and phylogenetic analyses. Pathogenicity tests confirmed A. alternata to be the causal agent of the newly observed leaf spot disease. This is the first report of leaf spot on D. maritima caused by A. alternata in the world. 相似文献
80.
Ricardo Rocha Milou Groenenberg Paulo E. D. Bobrowiec Mar Cabeza Jorge M. Palmeirim Christoph F. J. Meyer 《Landscape Ecology》2017,32(1):31-45