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21.
We examined the enzymatic saccharification and ethanol fermentation of the spent media (SMs) from Auricularia polytricha cultivation using wood meals of Falcataria moluccana, Shorea sp., and Tectona grandis. Although the hydrolysis weight decrease and reducing sugar yield were higher in SM of F. moluccana, the ethanol yield was higher in SM of Shorea sp. Ozone treatment of SM further increased the hydrolysis weight decrease, reducing sugar, and ethanol yields in Shorea sp. These results indicate that SM of A. polytricha is a suitable biomass material to produce fermentable sugars for ethanol production, and that ozone treatment is a suitable method for increasing the ethanol yield.  相似文献   
22.
Pelibuey and Suffolk sheep were compared as to their capacity to regulate body temperature under environmental hyperthermia by measuring their differences in cellular response to heat stress (HS). In a first experiment, seven Pelibuey and seven Suffolk ewes were kept in a climatic chamber for 6 h daily during 10 days (temperatures within the 18 to 39.5 °C range). As chamber temperature rose, sheep rectal temperature increased in both groups, but to a lesser extent in Pelibuey (0.3 °C) than in Suffolk sheep (0.7 °C) (P?<?0.05). In a second experiment, cellular viability was assessed using cultured blood mononuclear cells from 15 Pelibuey and 15 Suffolk sheep. They were incubated at 37 °C for 24 h (control) or 43 °C for 6 h followed by 18 h at 37 °C (HS). In a third experiment, another blood mononuclear cells culture from eight Pelibuey and eight Suffolk sheep was kept at 37 °C for 15 h; these were subsequently cultured for 6 h at 37 °C (controls) or 43 °C (HS). Next, HSP-70 concentration was determined. HS reduced the percentage of viable cells to a greater extent in Suffolk [37 °C (73.7 %) vs. 43 °C (61.9 %); P?<?0.05] than in Pelibuey sheep [37 °C (74.9 %) vs. 43 °C (66.7 %); P?>?0.05]. HS significantly increased HSP-70 average concentrations for both breeds at 43 °C. A significant effect was observed for the breed by temperature interaction (P?<?0.05) caused by a greater difference between Pelibuey and Suffolk at 43 °C (2.85 vs. 0.53 ng/mL, respectively; P?<?0.05) than at 37 °C (0.05 vs. 0.03 ng/mL, respectively; P?>?0.05). In conclusion, Pelibuey sheep show more effective body temperature regulation under conditions of environmental hyperthermia. Also, cell viability after HS was higher in Pelibuey than in Suffolk, an effect that could be mediated by an HSP-70-related mechanism.  相似文献   
23.
AIMS: To determine immune responses, and the localisation and persistence of Mycobacterium bovis bacille Calmette-Guérin (BCG) in gut-associated lymphoid tissues (GALT) and other organs in possums vaccinated orally with lipid-formulated BCG vaccine. To determine the duration of excretion and longevity of survival of BCG in the faeces of vaccinated animals.

METHODS: Possums (n=28) were vaccinated with lipid-formulated BCG (1 x 10 8 colony forming units (cfu) of formulated BCG) by the oral route. Control possums (n=17) were fed oral bait pellets containing formulation medium only. Possums were sacrificed at 3 days and at 1, 3, 6 and 8 weeks after vaccination or ingestion of bait. Proliferation responses to bovine purified protein derivative (PPD) were measured in lymphocytes from blood and mesenteric lymph nodes (MLN) and samples of lung, spleen, liver, MLN and Peyer's patches (PP) were cultured for the presence of BCG. The number of BCG organisms excreted in faeces and the duration of excretion were determined in eight vaccinated possums and eight control possums over a 3-week period. In a separate experiment, a further six possums were vaccinated with oral BCG vaccine (5–10 x 10 8 cfu BCG/possum) and their faeces collected over 48–72 h, for culture of BCG. The longevity of survival of BCG in these faeces was determined by storing faecal samples (n=12) under three different conditions: in an incubator (22.5°C), and conditions which simulated the forest floor and open pasture. A proportion (1–2 g) of these faecal samples was collected after storage for 1, 3, 5, 8 or 20 weeks, and cultured for BCG.

RESULTS: Possums vaccinated orally with BCG vaccine showed strong proliferation responses to bovine PPD in peripheral blood lymphocytes at 6–8 weeks post-vaccination (p.v.). Positive lymphocyte proliferation assay (LPA) responses to bovine PPD were first evident in MLN at 3 weeks p.v. BCG was cultured from MLN and PP in a proportion of animals at 3–8 weeks p.v. BCG was not cultured from sections of spleen, lung or liver at any time p.v. BCG was recovered in low to moderate numbers from the faeces of vaccinated possums for up to 7 days, and maximal numbers were cultured in faeces collected 48–72 h p.v. After storage for 1 week, BCG was cultured from all faecal samples placed in the incubator and from a proportion of faeces exposed to conditions similar to those on the forest floor and pasture. With the exception of one faecal sample stored under forest floor conditions which was culture-positive for BCG at 3 and 5 weeks, BCG was not cultured from any other faecal sample stored for more than 1 week.

CONCLUSIONS: Ingestion of oral BCG vaccine by possums was associated with the development of strong cell-mediated immunity in both blood and MLN. Following oral vaccination with BCG, the organisms were localised and persisted in GALT but did not spread to the spleen, liver or lungs. BCG was shed in low to moderate numbers in the faeces for up to 7 days p.v. The viability of BCG excreted in faeces decreased rapidly, particularly when faeces were exposed to an open pasture environment. Oral vaccination of possums with formulated BCG is unlikely to result in undue contamination of the environment with BCG.  相似文献   
24.
AIMS: To determine factors that may influence the efficacy of an oral pelleted vaccine containing Mycobacterium bovis bacille Calmette-Guérin (BCG) to induce protection of brushtail possums against tuberculosis. To determine the duration of protective immunity following oral administration of BCG.

METHODS: In Study 1, a group of possums (n=7) was immunised by feeding 10 pellets containing dead Pasteur BCG, followed 15 weeks later with a single pellet of live Pasteur BCG. At that time, four other groups of possums (n=7 per group) were given a single pellet of live Pasteur BCG orally, a single pellet of live Danish BCG orally, 10 pellets of live Pasteur BCG orally, or a subcutaneous injection of live Pasteur BCG. For the oral pelleted vaccines, BCG was formulated into a lipid matrix, and each pellet contained approximately 107 colony forming units (cfu) of BCG, while the vaccine injected subcutaneously contained 106 cfu of BCG. A sixth, non-vaccinated, group (n=7) served as a control. All possums were challenged by the aerosol route with a low dose of virulent M. bovis 7 weeks after vaccination, and killed 7–8 weeks after challenge. Protection against challenge with M. bovis was assessed from pathological and bacteriological findings.

In Study 2, lipid-formulated live Danish BCG was administered orally to three groups of possums (10–11 per group), and these possums were challenged with virulent M. bovis 8, 29 or 54 weeks later. The possums were killed 7 weeks after challenge, to assess protection in comparison to a non-vaccinated group.

RESULTS: The results from Study 1 showed that vaccine efficacy was not adversely affected by feeding dead BCG prior to live BCG. Feeding 10 vaccine pellets induced a level of protection similar to feeding a single pellet. Protection was similar when feeding possums a single pellet containing the Pasteur or Danish strains of BCG. All vaccinated groups had significantly reduced pathological changes or bacterial counts when compared to the non-vaccinated group. In Study 2, oral administration of Danish BCG induced protection against challenge with M. bovis, which persisted for at least 54 weeks after vaccination. Some protection was observed in possums challenged 54 weeks after vaccination, but this protection was significantly less than that observed in groups vaccinated 29 or 8 weeks prior to challenge. There was a strong relationship between the proportion of animals producing positive lymphocyte proliferation responses to M. bovis antigens and protection against challenge with M. bovis.

CONCLUSIONS: Factors considered potentially capable of interfering with vaccination, including feeding dead BCG to possums prior to feeding live BCG, feeding multiple doses of BCG at one time, and changing strains of BCG, were shown not to interfere with the acquisition of protective immune responses in possums. Protection against tuberculosis was undiminished up to 29 weeks after vaccination with BCG administered orally. It is concluded that vaccination of possums by feeding pellets containing BCG is a robust and efficient approach to enhance the resistance of these animals to tuberculosis.  相似文献   
25.
McGarvey JA  Denny TP  Schell MA 《Phytopathology》1999,89(12):1233-1239
ABSTRACT One susceptible and two resistant cultivars of tomato were tested for differences in infection by Ralstonia solanacearum and for the subsequent multiplication, colonization, and production of the wilt-inducing virulence factor, exopolysaccharide I (EPS I). Bacterial ingress into the taproot was fastest in the susceptible cv. Marion, followed by the resistant cvs. L285 (fivefold slower) and Hawaii 7996 (15-fold slower). Once inside the taproot, R. solanacearum colonized, to some extent, almost all regions of the resistant and susceptible plants. However, colonization occurred sooner in the susceptible than in the resistant cultivars, as measured by viablecell counts of bacteria in the midstems. Rates of multiplication and maximum bacterial cell densities were also greater in the susceptible than in the resistant cultivars. Growth experiments utilizing xylem fluid from infected and uninfected plants indicated that neither antimicrobial activities nor reduced levels of growth-supporting nutrients in the xylem fluids were responsible for the reduced bacterial multiplication in the resistant cultivars. Quantification of EPS I in the infected plants, using an enzyme-linked immunosorbent assay, revealed that the bacterial populations in the susceptible cultivar produced greater amounts of EPS I per plant than those in the resistant cultivars. Immunofluorescence microscopy using antibodies against either EPS I or R. solanacearum cells revealed that bacteria and EPS I were distributed throughout the vascular bundles and intercellular spaces of the pith in the susceptible cultivar, whereas in the resistant cultivars, bacteria and EPS I were restricted to the vascular tissues.  相似文献   
26.
This paper presents the results of the first formal epidemiological study in Northern Ireland of risk factors for bovine tuberculosis (TB) associated with farm boundaries, neighbours and wildlife. The study was designed as a case-control study and 427 dairy herds were investigated between December 1993 and January 1995. The case herds had more than 30 cattle, and herds in which the source of infection had been ascribed to purchased cattle were avoided. Data on the Department of Agriculture Animal Health Computer were used in conjunction with data collected through a questionnaire to examine a range of possible risk factors, including the number and nature of the farm boundaries, the number of neighbours and their TB history, the number of hedgerows, the presence of badger setts, whether badger carcases had been found on the land, and the possible presence of deer. A follow-up telephone survey was conducted to minimise bias. The results highlighted two main associations with TB breakdowns, the presence of badgers, and contiguous neighbours who had had confirmed TB breakdowns. The estimated aetiological fraction for both associations was approximately 40 per cent, suggesting that although infected cattle may have a significant role in the transmission of TB their importance relative to the badger may have been over-estimated in the Northern Ireland TB scheme. The contribution of the badger is possibly one of several main reasons for the lack of significant progress in TB eradication despite strenuous efforts associated with all aspects of the scheme.  相似文献   
27.
28.
The indications for laparotomy in 140 horses are analysed, with particular emphasis on the operative or autopsy findings in 82 cases of colic. In cases of exploratory laparotomy, the overall recovery rate was only 28 per cent but 48 of the 82 animals were considered to have inoperable lesions. The recovery rate and causes of death for each indication are briefly reviewed.  相似文献   
29.
Pelvic fractures in the dog: a review of 123 cases   总被引:1,自引:0,他引:1  
  相似文献   
30.
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