Rough vaccines in animal brucellosis: structural and genetic basis and present status   总被引：14，自引：0，他引：14  

Moriyón I  Grilló MJ  Monreal D  González D  Marín C  López-Goñi I  Mainar-Jaime RC  Moreno E  Blasco JM 《Veterinary research》2004,35(1):1-38

Brucellosis control and eradication requires serological tests and vaccines. Effective classical vaccines (S19 in cattle and Rev 1 in small ruminants), however, induce antibodies to the O-polysaccharide of the lipopolysaccharide which may be difficult to distinguish from those resulting from infection and may thus complicate diagnosis. Rough attenuated mutants lack the O-polysaccharide and would solve this problem if eliciting protective immunity; the empirically obtained rough mutants 45/20 and RB51 have been used as vaccines. Strain 45/20 is reportedly unstable and it is not presently used. RB51 is increasingly used instead of S19 in some countries but it is rifampicin resistant and its effectiveness is controversial. Some controlled experiments have found good or absolute protection in adult cattle vaccinated orally (full dose) or subcutaneously (reduced dose) and in one field experiment, RB51 was reported to afford absolute protection to calves and to perform better than S19. Controlled experiments in calves, however, have shown reduced doses of RB51 to be ineffective, full doses only partially effective, and RB51 less effective than S19 against severe challenges. Moreover, other observations suggest that RB51 is ineffective when prevalence is high. RB51 is not useful in sheep and evidence in goats is preliminary and contradictory. Rough mutants obtained by molecular biology methods on the knowledge of the genetics and structure of Brucella lipopolysaccharide may offer alternatives. The B. abortus manBcore (rfbK) mutant seems promising in cattle, and analyses in mice suggest that mutations affecting only the O-polysaccharide result in better vaccines than those affecting both core and O-polysaccharide. Possible uses of rough vaccines also include boosting immunity by revaccination but solid evidence on its effectiveness, safety and practicality is not available.  相似文献   

In vitro effect of classical swine fever virus on a porcine aortic endothelial cell line     

Campos E  Revilla C  Chamorro S  Alvarez B  Ezquerra A  Domínguez J  Alonso F 《Veterinary research》2004,35(6):625-633

The effect of classical swine fever (CSF) virus on some phenotypic and functional features of an established porcine aortic endothelial cell (AOC) line was investigated. AOC cells show most of the characteristics of primary endothelial cells, avoiding the alterations and senescence that these cells undergo after a few passages in culture. AOC cells were susceptible to CSF virus infection to a high degree, reaching 90% of CSF virus positive cells after 24 h of infection; however as with other porcine susceptible cells, no cytopathic effect could be observed. In these conditions none of the surface molecules studied, including SLA-II MHC antigens, adhesion or co-stimulatory molecules, were altered by virus infection after 24 or 48 h. Functionally CSF virus infection induced a decrease in the pro-coagulant activity of the AOC cells, determined by the increase in the clot formation time shown by the lysates of these cells. This contrasts with the increase observed in the expression of mRNA corresponding to IL-1 alpha and IL-6, two proinflammatory and pro-coagulant cytokines, in CSF virus-infected AOC cells.  相似文献   

Haptoglobin and pig-major acute protein are increased in pigs with postweaning multisystemic wasting syndrome (PMWS)     

Segalés J  Piñeiro C  Lampreave F  Nofrarías M  Mateu E  Calsamiglia M  Andrés M  Morales J  Piñeiro M  Domingo M 《Veterinary research》2004,35(3):275-282

The objective of this study was to determine the serum concentration levels of selected acute phase proteins (APP), haptoglobin (HPT) and pig-major acute phase protein (pig-MAP), in postweaning multisystemic wasting syndrome (PMWS) affected pigs and PCV2-subclinically infected pigs. In a first study, a group of 15 eight-week-old conventional pigs from a PMWS affected farm were bled and a complete necropsy, histopathology and in situ hybridisation to detect PCV2 were performed. Based on the results, pigs were classified as suffering from PMWS (n = 10) or healthy animals (n = 5). In a second study, a group of 45 pigs from another PMWS affected farm were selected and bled at 3, 7, 12 and 28 weeks of age. The assessment of PCV2 infection status in these pigs was retrospectively done by PCV2 PCR in serum samples. Selected APP were measured in the serum of all studied pigs by means of radial immunodiffusion. Mean HPT and pig-MAP levels were significantly increased (p = 0.004 and p = 0.0006 respectively) in PMWS-affected pigs when compared to levels found in healthy pigs (2.52 +/- 0.88 mg/mL vs. 1.06 +/- 0.73 mg/mL for HPT and 3.81 +/- 1.53 mg/mL vs. 0.76 +/- 0.34 mg/mL for pig-MAP). In the second study, no significant difference in mean HPT and pig-MAP values were observed between PCV2 PCR positive and negative pigs of any age. However, both APP increased significantly with age in PCV2 PCR negative pigs. Altogether, the present results suggest that APP levels are significantly increased in pigs that develop PMWS, but not in animals with a PCV2 subclinical infection.  相似文献   

Changes in selected serum parameters of broiler chicken fed supplemental chromium   总被引：2，自引：0，他引：2  

Króliczewska B  Zawadzki W  Dobrzanski Z  Kaczmarek-Oliwa A 《Journal of animal physiology and animal nutrition》2004,88(11-12):393-400

The present study was conducted to evaluate the effect of chromium (Cr) from Cr yeast on the growth performance and total cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, triglycerides, glucose, total protein and Cr concentration in the serum of broiler chicken. The birds were fed a control diet or a control diet supplemented with Cr at a level of 300, 500 microg/kg Cr. The supplementation of 500 mug/kg Cr increased body weight, weight gain and feed efficiency (p < 0.05). In addition, supplementation with Cr decreased the serum total cholesterol, LDL cholesterol (p < 0.05), triglycerides (p < 0.05) and glucose (p < 0.05) concentrations whereas serum HDL cholesterol increased. Serum total protein and serum Cr concentration slightly but not significantly increased in both Cr groups. The study suggest that Cr supplementation particularly at 500 microg/kg Cr from Cr yeast can influence on carbohydrate and lipid metabolism of broiler chicken and can be used as additives in animal diet but it still needs more investigations.  相似文献   

Reactivity of the immunological system of turkeys vaccinated with the Newcastle virus after intoxication with carbaryl     

Wójcik R  Swiecicka-Grabowska G 《Polish journal of veterinary sciences》2004,7(1):9-13

Research has shown that among pesticides, carbaryl is one of the strongest immunosuppressors for numerous animal species. In this paper, the effect of carbaryl on biochemical parameters and on specific and non-specific immunity in carbaryl-intoxicated birds was determined. The results indicate a significant immunosuppressive effect in turkeys, on almost all the investigated biochemical parameters and on the indices of specific and non-specific immunity. The only exception is a slightly elevated level of total protein and reactivity of T lymphocytes to non-specific mitogen in the group of intoxicated birds.  相似文献   

Modification of zearalenone structure in model and natural conditions     

Góra M  Luczyński MK  Smoczyński L  Obremski K  Polak M  Swist M  Zielonka L  Gajecki M 《Polish journal of veterinary sciences》2004,7(3):181-185

Zearalenone is a mycotoxin widely occurring in cereals and animal feed, and it is associated with hyperestrogenism and other reprodutive disorders in animals. A new method of detoxication of feedstuffs involves alkaline hydrolysis of toxic macrolactone (1) (as well as model compounds (2a, 2b)). The method caused modification of zearalenone structure under mild conditions and the toxin underwent irreversible hydrolysis with high efficiency.  相似文献   

Changes in chymotrypsin hydrolysis of beta-lactoglobulin A induced by high hydrostatic pressure     

Chicón R  López-Fandiño R  Quirós A  Belloque J 《Journal of agricultural and food chemistry》2006,54(6):2333-2341

Beta-lactoglobulin (beta-Lg) was subjected to high pressures up to 400 MPa and proteolysis with chymotrypsin. The hydrolysates were analyzed by SDS-PAGE and RP-HPLC, and the fragments obtained were identified by ESI-MS/MS. The results obtained showed that beta-Lg was hydrolyzed by chymotrypsin in a "progressive proteolysis" manner at either atmospheric or high pressure. Proteolysis during or after high-pressure treatment showed longer and more hydrophobic peptides than proteolysis at atmospheric pressure. Chymotrypsin showed a behavior similar to that of trypsin, with some differences, probably related to the orientation of the target residues specific for each enzyme. The similarities between proteolytic fragments produced by the two enzymes support that proteolysis enhancement under high pressure depends on the substrate changes rather than the enzyme. High pressure seemed to accelerate the first steps of proteolysis, probably through dimer dissociation, while leaving portions of the molecule more resistant to the enzyme.  相似文献   

Save the lab in Montemar, Chile     

Borges R  Viveros OH  Latorre R 《Science (New York, N.Y.)》2006,311(5769):1866

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The effect of beta-glucanase supplementation of barley- and oat-based diets on growth performance and fermentation in broiler chicken gastrointestinal tract     

Józefiak D  Rutkowski A  Jensen BB  Engberg RM 《British poultry science》2006,47(1):57-64

1. The aim of the present study was to investigate whether grain type (barley or oats) and ss-glucanase inclusion influence the performance and the gastrointestinal ecosystem of broiler chickens, taking the concentrations of short-chain fatty acids and lactic acid, pH, ileal viscosity, and the weight of the caeca and liver into consideration. 2. The inclusion of beta-glucanase in the oat-based diet improved body weight gains. Enzyme supplementation of barley-based diets improved feed conversion efficiency and reduced intestinal viscosity. 3. Irrespective of the type of cereal, beta-glucanase supplementation increased the lactic acid concentration and lowered the pH of the crop contents. No such changes in fermentation were observed in the contents of the gizzard and ileum. 4. Larger amounts of total dietary fibre and its fractions (arabinoxylans and beta-glucans) in oats decreased the weight of the caeca. 5. Molar ratios of acetate, propionate and butyrate in the caecal chyme were affected by cereal type but not by enzyme supplementation. The barley-based diet increased the butyrate:propionate ratio but the opposite effect was observed with the oat-based diet.  相似文献   

Effects of long-term dietary supplementation of monensin or saccharomyces cerevisiae on blood acid-base and productive performance in growing feedlot steers     

Castillo C  Benedito JL  Méndez J  García-Partida P  Vázquez P  Pereira V  López-Alonso M  Hernández J 《Berliner und Münchener tier?rztliche Wochenschrift》2006,119(11-12):480-485

The aim of this study was to evaluate the effects of two dietary supplements (monensin and a live yeast culture) on acid-base balance in steers maintained in a commercial feedlot system, considering effects over the growing period (14 to 23 weeks of age). A 63-day feedlot study was performed using 42 double-muscled Belgian Blue steers. Steers were allotted randomly to one of the three study groups: (1) control group [no supplementation, C], (2) monensin supplementation [MON] at a concentration of 30 mg/kg (DM basis), and (3) live Saccharomyces cerevisiae strain supplementation [SACC] at a dose of 500 mg/kg (DM basis).Venous blood samples were collected for the measurement of acid-base parameters and L-lactate. Production parameters were also used as a complementary tool for understanding the internal changes associated with supplementation. Our results show that during the study period no statistical differences were observed between supplemented and control steers, although non-supplemented animals tended to gain more efficiently than those fed monensin or yeast. Nevertheless, taking into account blood parameters, these control animals showed a greater risk of acid overload due to a more marked decline in blood buffer levels over time in comparison with supplemented steers although no differences were observed between monensin or yeast supplemented animals. Additionally, significant effect of supplementation was observed in packed cell volume (PCV) values.  相似文献