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1.
Withanage GS Sasai K Fukata T Miyamoto T Baba E 《Veterinary immunology and immunopathology》1999,67(2):185-193
The production and secretion of Salmonella enteritidis whole cell antigen-specific antibodies in the oviducts and in the serum of laying hens experimentally infected with Salmonella enteritidis, was analyzed by ELISA. The dynamics of the antibody levels in the oviducts were identical to that in the serum. Subclasses of antibodies (IgA, IgG, and IgM) in the infected hens were found to increase significantly (p < 0.01) compared to those in the control uninfected hens throughout the experiment. IgG and IgM levels in both oviducts and in sera reached to a peak by 14 days post-inoculation, and remained elevated throughout. The secretion of IgA seemed to be transient since the IgA levels increased to a peak 7 days after both primary and secondary inoculations, and declined rapidly. The elevated levels of antibodies were followed by partial clearance of Salmonella organisms from the oviducts. The present results indicate a significant local immune reaction against the Salmonella infection and suggest an association of the local antibodies with the clearance of Salmonella from the oviducts at least partially. 相似文献
2.
Withanage GS Mastroeni P Brooks HJ Maskell DJ McConnell I 《British poultry science》2005,46(3):261-267
Phagocytes limit replication or kill ingested organisms by producing toxic reactive oxygen and nitrogen species via NADPH oxidase and inducible nitric oxide synthase (iNOS). The present experiments were to investigate the production and the possible roles of superoxide, hydrogen peroxide (H2O2) and nitric oxide (NO) in the MQ-NCSU chicken macrophage cell line infected with Salmonella in vitro. After infection, intracellular Salmonella viable counts remained constant until 24 h post infection (PI) and started to decline from 48 h PI. Infection of cells with S. Typhimurium, S. Enteritidis and S. Gallinarum, as well as exposure to S. Enteritidis LPS induced low, but significant concentrations of superoxide 1 to 2 h PI, as determined by reduction of ferricytochrome c. There was no difference in superoxide production in infected cells and control cells after 4 h. Increased H2O2 was observed from cells infected with all the different Salmonella species between 2 and 3 h of infection. Nitrite was always greater in infected cells compared to uninfected cells at all times. However, Salmonella was not completely eliminated from the cells though these cells are capable of eliciting a noticeable oxidative burst response and great nitrosative responses, indicating that a strong oxidative burst (and other mechanism/s) is essential for the elimination of intracellular Salmonella. 相似文献
3.
The efficacy of Salmonella enteritidis (SE) oil-emulsion bacterin (a commercially available vaccine) was evaluated in an intravaginal challenge model in hens producing a high rate of SE-contaminated eggs. Hens were vaccinated at 38 wk of age. A second (booster) bacterin injection was administered 4 wk later. Two weeks after the second vaccination, all hens were challenged intravaginally with 10(7) colony-forming units of SE. After challenge, 36 of 189 eggs (19.0%) in the vaccinated hens were positive for SE, and this contamination rate was significantly (P < 0.01) lower than that in the unvaccinated hens (61 of 165 eggs, 37.0%). SE was highly recovered from the cloacal and vaginal swabs of the unvaccinated and vaccinated hens, but the number of SE from the cloaca of the vaccinated hens was significantly (P < 0.05) lower than that in the unvaccinated hens at 7 days post-challenge (PC). The recoveries of SE from the spleen and ovary in the vaccinated hens were significantly (P < 0.05) lower than those in the unvaccinated hens at 7 days PC. At necropsy, SE was recovered from 2 of 15 forming eggs (13.3%) taken from the oviducts of the unvaccinated hens, whereas no SE was recovered from 17 forming eggs in the vaccinated hens. After vaccination, serum antibodies for SE in the vaccinated hens were significantly higher than those in the unvaccinated hens. Antibodies from the oviductal washing, especially immunoglobulin G isotype, in the vaccinated hens were higher than those in the unvaccinated hens after challenge. This intravaginal challenge model produced frequent contaminated eggs and clearly demonstrated the ability of the bacterin to protect against egg contamination. The present model may be a useful tool for further studies to evaluate the protective effect against SE contamination of eggs by potential vaccine candidates. 相似文献
4.
Maureen Kumaunang Chatthaphisuth Sanchart Wasana Suyotha 《Journal Of Aquatic Food Product Technology》2013,22(8):877-890
Fermented shrimp paste (Kapi) is traditionally produced using a high content of salt and mainly consumed as a food condiment by the Thai people. In order to select potential functional autochthonous starter culture, the protease-producing bacteria from Kapi were isolated, screened, and evaluated for technological and safety aspects. Among 195 isolates, five bacterial strains (MSK-3P, MSK-4P, MSK-5P, MSK-7P, and MSK-10P) exhibited the highest activity of protease using Anson method. All of them were identified as Virgibacillus halodenitrificans using 16S rRNA sequence analysis. All selected strains exhibited growth in the presence of NaCl up to 25%. Neither strain showed hemolytic activity nor biogenic amine formation. Among all selected strains, only strain MSK-10P had no ability to form a biofilm, while four other strains showed a weak ability. Strain MSK-7P exhibited multiple resistances to tetracycline and vancomycin, while strains MSK-3P, MSK-4P, and MSK-10P showed susceptibility to all antibiotics tested. According to the obtained results, this protease-producing V. halodenitrificans MSK-10P is a good candidate for further investigation for use in Kapi fermentation to assess its technological performance as a autochthonous starter culture. 相似文献
5.
Penprabha Piyadhammaviboon Wasana Wongngam Soottawat Benjakul 《Journal Of Aquatic Food Product Technology》2013,22(3):265-278
Solid wastes from threadfin bream (Nemipterus spp.) surimi production composed of head and frame were hydrolyzed by various commercial proteases (Alcalase, Flavourzyme, Neutrase, Protamex, papain, and pepsin) to produce protein hydrolysates with bioactive properties. An Alcalase-hydrolyzed sample at 24.4% degree of hydrolysis (DH) displayed the highest antioxidant activity based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power (FRAP) assay, and potassium ferricyanide method. In addition, it showed an inhibitory activity toward angiotensin-converting enzyme (ACE) of 25.5%. Antioxidant activity of threadfin bream by-product hydrolysates increased with hydrolysis time and reached the highest DPPH activity after 6 h, while that hydrolyzed for 3 h showed the highest reducing power based on FRAP and potassium ferricyanide assays. In addition, ACE inhibitory activity was found to be at an optimum after 3 h of hydrolysis. The hydrolysates (1 mg/mL) also retarded oxidation of a linoleic acid emulsion system to a similar extent as 0.1 mg/mL 3-tert-butyl-4-hydroxy anisole (BHA), indicating a potential use in the food system. Protein hydrolysates from threadfin bream surimi by-products could be tailor-made to possess both antioxidant and ACE inhibitory activity through controlling DH of Alcalase-catalyzed reactions. 相似文献
6.
Sorption and desorption of Hg(II) on clay minerals can impact the biogeochemical cycle and bio-uptake of Hg in the environment. We studied the kinetics of the desorption of Hg(II) from kaolinite as affected by oxalate and cysteine, representing the ligands with carboxylic and thiol groups of different affinities for Hg(II). The effects of pH (3, 5, and 7), ligand concentration (0.25 and 1.0?mM), and temperature (15??C, 25??C, and 35??C) on the Hg(II) desorption were investigated through desorption kinetics. Our study showed that the Hg(II) desorption was pH dependent. In the absence of any organic ligand, >90% of the previously adsorbed Hg(II) desorbed at pH?3 within 2?h, compared to <10% at pH?7. Similar results were observed in the presence of oxalate, showing that it hardly affected the Hg(II) desorption. Cysteine inhibited the Hg(II) desorption significantly at all the pH tested, especially in the first 80?min with the desorption less than 20%, but the inhibition of the desorption appeared to be less prominent afterwards. The effect of the ligand concentration on the Hg(II) desorption was small, especially in the presence of oxalate. The effect of temperature on the Hg(II) desorption was nearly insignificant. The effect of the organic acids on the Hg(II) sorption and desorption is explained by the formation of the ternary surface complexes involving the mineral, ligand, and Hg(II). The competition for Hg(II) between the cysteine molecules adsorbed on the particle surfaces and in the solution phase probably can also affect the Hg(II) desorption. 相似文献
7.
Cook SM Higuchi DS McGowan AL Schrader JS Withanage GS Francis MJ 《Avian diseases》2010,54(4):1152-1156
Diagnosis of turkey Eimeria infection by conventional parasitologic methods is challenging and, until now, no molecular tools existed that clearly distinguished the four widely recognized pathogenic species: Eimeria adenoeides, E. meleagrimitis, E. gallopavonis, and E. dispersa. In this study, the internal transcribed spacer region one (ITS-1) was amplified and sequenced from 23 conventionally characterized reference samples. Phylogenic analysis segregated samples into five distinct cluster groups. The ITS-1 region(s) within each cluster were of a particular length and shared from 96% to 100% identity, while amplified ITS-1 region(s) between clusters differed in length and shared only 10.6% to 49.7% sequence identity. In addition, we developed PCR primer sets as diagnostic tools capable of specifically identifying members of each of the five clusters. 相似文献
8.
Wasana Suebsong Supawadee Poompuang Prapansak Srisapoome Skorn Koonawootrittriron Amorn Luengnaruemitchai Harry Johansen Morten Rye 《Journal of fish diseases》2019,42(11):1553-1562
The potential of selection to improve resistance to streptococcosis was evaluated in a commercial population of Nile tilapia in Thailand. The base generation (G0) consisted of offspring from 98 sires and 149 dams using a partly nested design. At 60 days post‐hatch, 30 fish from each family were injected intraperitoneally with a Streptococcosis agalactiae solution (1 × 109 CFU/ml) and evaluated for 14 days. Disease resistance was recorded as the number of days from challenge until death (DD) and as a binary (BIN) trait (dead/alive) on day 14. Three models were used for genetic analyses: Cox frailty model for DD; animal model for DD; and animal model for BIN. Age at challenge was fitted as a covariate and contemporary group as fixed or random effect, depending on the model. Fish from the 18 most resistant families were selected to produce the first generation (G1). Heritability estimates for G0 were 0.22, 0.14 ± 0.02 and 0.11 ± 0.02 for the Cox, linear DD and linear BIN models, respectively. Selection response indicated that the risk of death decreased to 54%, survival time increased to 3.4 days and survival rate increased to 21%. These results suggest that genetic improvement is possible for this population. 相似文献
9.
Jirawat Yongsawatdigul Saowanee Pivisan Wasana Wongngam Soottawat Benjakul 《Journal Of Aquatic Food Product Technology》2013,22(5):460-473
Small-scale mud carp (SC, Cirrhina microlepis) and common carp (CC, Cyprinus carpio) are underutilized freshwater fish. The objective of this study was to elucidate the gel-forming ability of mince and washed mince from these species in relation to washing cycles and CaCl2 addition. Protein loss of up to 67% was observed after three-washing cycles of both species, rendering relatively low yield. About 85–90% of total fat was removed from SC flesh after three-washing cycles, but only two-washing cycles were sufficient for fat removal in CC mince. Mince and washed mince of both species did not exhibit severe proteolysis with low autolytic activity at 65°C. SC exhibited superior gel-forming ability to CC. Two- and three-washing cycles in conjunction with a 40°C-preincubation resulted in the highest textural properties of SC and CC, respectively. CaCl2 increased the breaking force of CC and SC mince gels up to 65 and 95% at 0.3 and 0.5% CaCl2, respectively, as compared to without CaCl2. However, it showed negative effects on surimi gels of both species. Both SC and CC are potential freshwater fish resources for mince and washed mince production with reasonable good gel-forming ability. 相似文献
10.
Withanage Prasadini Wasana Amal Senevirathne Chamilani Nikapitiya Tae-Yang Eom Youngdeuk Lee Jong-Soo Lee Do-Hyung Kang Chulhong Oh Mahanama De Zoysa 《Marine drugs》2021,19(12)
A marine bacterial strain was isolated from seawater and characterized for it beneficial probiotic effects using zebrafish as a model system. The strain was identified by morphological, physiological, biochemical, and phylogenetic analyses. The strain was most closely related to Pseudoalteromonas xiamenensis Y2, with 99.66% similarity; thus, we named it Pseudoalteromonas xiamenensis S1131. Improvement of host disease tolerance for the P. xiamenensis isolate was adapted in a zebrafish model using Edwardsiella piscicida challenge. The larvae were pre-exposed to P. xiamenensis prior to E. piscicida challenge, resulting in a 73.3% survival rate compared to a 46.6% survival for the control. The treated larvae tolerated elevated temperatures at 38 °C, with 85% survival, compared to 60% survival for the control. Assessment of immunomodulatory responses at the mRNA level demonstrated the suppression of pro-inflammatory markers tnfα and il6, and upregulation of heat shock protein hsp90 and mucin genes. The same effect was corroborated by immunoblot analysis, revealing significant inhibition of Tnfα and an enhanced expression of the Hsp90 protein. The antibacterial activity of P. xiamenensis may be related to mucin overexpression, which can suppress bacterial biofilm formation and enhance macrophage uptake. This phenomenon was evaluated using nonstimulated macrophage RAW264.7 cells. Further studies may be warranted to elucidate a complete profile of the probiotic effects, to expand the potential applications of the present P. xiamenensis isolate. 相似文献