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21.
Currently, mesenchymal stem cells (MSCs) are used in veterinary clinical applications. Bone marrow and adipose tissue are the most common sources of stem cells derived from adult animals. However, cord blood which is collected non‐invasively is an alternative source of stem cells other than bone marrow and adipose tissue. Moreover, high availability and lower immunogenicity of umbilical cord blood (UCB) haematopoietic stem cells compared to other sources of stem cell therapy such as bone marrow have made them a considerable source for cell therapy, but MSCs is not highly available in cord blood and their immunogenicity is poorly understood. In this study, the cells with spindle morphology from 7 of 9 bovine UCB samples were isolated and cultured. These mesenchymal stromal cells were successfully differentiated to osteocytes, chondrocytes and adipocytes. In addition, Oct‐4 and SH3 were determined by RT‐PCR assay. It is the first report of isolation, culture, characterization and differentiation of bovine umbilical stem cells.  相似文献   
22.
AIMS: To examine pigs at slaughter in New Zealand for the presence of Pasteurella multocida, and to determine for isolates, their biochemical profiles, somatic and capsular types, and the presence or absence of the HSB and toxA genes, associated with haemorrhagic septicaemia (HS) and progressive atrophic rhinitis (PAR), respectively.

METHODS: Swabs from 173 lungs, 158 palatine tonsils and 82 nasal passages of pigs at two abattoirs in New Zealand were cultured for P. multocida using conventional techniques, and isolated colonies were subjected to biochemical tests for identification of biovars. Somatic serotyping was conducted using an agar gel immunodiffusion (AGID) test. Polymerase chain reaction (PCR) assays were used to confirm phenotypic identification of colonies using species-specific primers, capsule type using serogroup-specific primers and multiplex PCR, and to test for the presence of HSB and toxA genes.

RESULTS: Pasteurella multocida was isolated from 11/173 (6.4%) lung, 32/158 (20.2%) palatine tonsil and 5/82 (6.1 %) nasal swab samples, a total of 48 isolates from 413 samples (11.6%). Isolation rates per farm ranged from 1–53% of tissue samples collected from pigs 5–6 months of age. On phenotypic characterisation, isolates were allocated to seven main biovars, viz 1, 2, 3, 5, 9, 12, and a dulcitol-negative variant of Biovar 8, the majority (30/48) being Biovar 3. Of the 42 isolates for which somatic serotyping was conducted, 10% were Serovar 1, 79% were Serovar 3, 2% were Serovar 6,1, 2% were Serovar 12, and 7% could not be typed. All 48 isolates were confirned as P. multocida using a species-specific PCR. In the capsular multiplex PCR, 92% of isolates were Capsular (Cap) type A, 2% were Cap D, and 6% could not be typed. None of the samples were positive for the HSB or toxA genes.

CONCLUSION: Serovars or capsular types of P. multocida associated with HS or PAR in pigs were not detected. Establishment of species-specific, capsular and toxin PCR assays allowed the rapid screening of isolates of P. multocida, while serotyping provided an additional tool for epidemiological and tracing purposes.  相似文献   
23.
AIM: To determine the aetiolog y of a recurring and severe form of infectious keratoconjunctivitis (IKC) in sheep.

METHODS: Five sheep flocks that had experienced a severe form of IKC were examined. Clinical history, conjunctival swabs and blood samples were collected from affected animals. Culture for bacteria, and also specifically for Mycoplasma and Chlamydophila spp, and detection of Mycoplasma conjunctivae DNA by polymerase chain reaction (PCR) were attempted. Serum samples were tested for antibodies to M. agalactiae, M. capricolum, M. conjunctivae and Chlamydophila spp.

RESULTS: Mycoplasma conjunctivae DNA was detected using PCR in 3/5 flocks, and in all flocks antibodies to M. conjunctivae were detected in sera. A pure growth of Branhamella ovis was cultured from conjunctival swabs from a small proportion of sheep in two flocks. No other pathogens were detected.

CONCLUSIONS: This investigation demonstrated that M. conjunctivae was a primary pathogen causing severe IKC in sheep, and is the first report of detection of this organism in sheep in New Zealand. Introduction of clinically normal carrier sheep appeared to have caused the outbreaks.  相似文献   
24.
25.
SUMMARY Three groups of 15 to 17 adult fallow does with some additional yearling does in 2 of the groups were treated to synchronise oestrous cycles, and mated. All does were scanned by ultrasound at 4 weeks of gestation and at weekly intervals from week 7 to week 14 of gestation. Growth rates of 13 foetal and uterine characters, which have been used for ageing foetuses of red deer, were similar for adult and yearling does and among the 3 groups. Transrectal ultrasound scanning was a reliable and accurate means of detecting pregnancy and of ageing foetuses of fallow deer during weeks 7 to 17 of pregnancy.  相似文献   
26.
Forestry variables are usually calculated at a forest managementunit scale. However, a region's forestry sector is affectedby various other factors that interact over space and time,many of which are not directly associated to silvicultural activitiesbut nonetheless play an important part in its development froma socio-economic or environmental point of view. To understanda region's forestry dynamics, and especially to predict itsfuture tendencies, we must include all the necessary variablesin a single database, calculated for spatial units that arestable over time and adequate for planning purposes. In ourstudy, we developed a Forest Geographic Information System forGalicia called ‘SIFGa’. We used it to examine 310variables describing the environment, population tendencies,land tenure and forest management in the Spanish autonomousregion of Galicia, at both council and parish levels. Resultsreveal the connections between our variables, which reflectthe changes the regional forestry sector has experienced inthe past, and explain its current situation. They also confirmthe heterogeneity of forestry in the area and the need to adaptforest-planning strategies to each study unit, as well as tothe entire region.  相似文献   
27.

Objective

To evaluate the effect of Equivac® HeV Hendra virus vaccine on Thoroughbred racing performance.

Design

Retrospective pre‐post intervention study.

Methods

Thoroughbreds with at least one start at one of six major south‐eastern Queensland race tracks between 1 July 2012 and 31 December 2016 and with starts in the 3‐month periods before and after Hendra virus vaccinations were identified. Piecewise linear mixed models compared the trends in ‘Timeform rating’ and ‘margin to winner’ before and after initial Hendra virus vaccination. Generalised linear mixed models similarly compared the odds of ‘winning’, ‘placing’ (1st–3rd) and ‘winning any prize money’. Timeform rating trends were also compared before and after the second and subsequent vaccinations.

Results

Analysis of data from 4208 race starts by 755 horses revealed no significant difference in performance in the 3 months before versus 3 months after initial Hendra vaccination for Timeform rating (P = 0.32), ‘Margin to winner’ (P = 0.45), prize money won (P = 0.25), wins (P = 0.64) or placings (P = 0.77). Further analysis for Timeform rating for 7844 race starts by 928 horses failed to identify any significant change in Timeform rating trends before versus after the second and subsequent vaccinations (P = 0.16) or any evidence of a cumulative effect for the number of vaccines received (P = 0.22).

Conclusion

No evidence of an effect of Hendra virus vaccination on racing performance was found. The findings allow owners, trainers, industry regulators and animal health authorities to make informed decisions about vaccination.  相似文献   
28.
The use of vesicles co‐incubated with plasmids showed to improve the efficiency of cytoplasmic injection of transgenes in cattle. Here, this technique was tested as a simplified alternative for transgenes delivery in porcine zygotes. To this aim, cytoplasmic injection of the plasmid alone was compared to the injection with plasmids co‐incubated with vesicles both in diploid parthenogenic and IVF zygotes. The plasmid pcx‐egfp was injected circular (CP) at 3, 30 and 300 ng/μl and linear (LP) at 30 ng/μl. The experimental groups using parthenogenetic zygotes were as follows: CP naked at 3 ng/μl (N = 105), 30 ng/μl (N = 95) and 300 ng/μl (N = 65); Sham (N = 105); control not injected (N = 223); LP naked at 30 ng/μl (N = 78); LP vesicles (N = 115) and Sham vesicles (N = 59). For IVF zygotes: LP naked (N = 44) LP vesicles (N = 94), Sham (N = 59) and control (N = 79). Cleavage, blastocyst and GFP+ rates were analysed by Fisher's test (p < 0.05). The parthenogenic CP naked group showed lower cleavage respect to control (p < 0.05). The highest concentration of plasmids to allow development to blastocyst stage was 30 ng/μl. There were no differences in DNA fragmentation between groups. The parthenogenic LP naked group resulted in high GFP rates (46%) and also allowed the production of GFP blastocysts (33%). The cytoplasmic injection with LP vesicles into parthenogenic zygotes allowed 100% GFP blastocysts. Injected IVF showed higher cleavage rates than control (p < 0.05). In IVF zygotes, only the use of vesicles produced GFP blastocysts. The use of vesicles co‐incubated with plasmids improves the transgene expression efficiency for cytoplasmic injection in porcine zygotes and constitutes a simple technique for easy delivery of plasmids.  相似文献   
29.
The southern Australian landscape is characterised by large climatic variability and an old, weathered surface with generally low hydraulic gradients. Many of these landscapes are prone to salinisation. The original ecosystems have strategies to cope with this environment in ways which minimise runoff and groundwater recharge. Replacement of these ecosystems with conventional agriculture has resulted in large-scale disruption of the natural water cycle with severe environmental, economic and social consequences. Sustainable agricultural systems aimed at mimicking natural hydrology must either minimise groundwater recharge over most of this landscape or intercept groundwater discharge in lower parts of the landscape prior to salinisation to restore the original hydrological balance. Empirical and theoretical analyses suggest that however vegetation is managed in the landscape, effective water balance control will be achieved only at a leaf area index approaching that of the natural state, indicating revegetation of most or all parts of the catchment with either trees or plants with similar ecohydrological characteristics as trees. There are at present few economically- attractive agricultural systems able to achieve hydrologic mimicry likely to be adopted at the necessary scale. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
30.
Leptospirosis is a zoonosis, found worldwide, affecting many species of animals. We conducted a cross-sectional study to estimate the prevalence of Leptospira borgpetersenii sv Hardjo and Leptospira interrogans sv Pomona in cattle in dairy herds in South-Western Victoria, Australia. Fifty-three herds were enrolled in the study. Urine samples were collected from 15 late-lactation cows in each herd. A questionnaire was provided to herd managers at the time of each herd visit, asking them to describe the methods they used for controlling leptospirosis, including vaccination. Urine samples were pooled at the herd level and tested for leptospira spp. using real time PCR. Urine samples from individual cows within the positive pooled samples were then tested for Leptospira Hardjo and Leptospira Pomona using qPCR. Four of the 53 herds showed positive leptospirosis results giving an apparent prevalence of 8 (95% CI 2–18) leptospira-positive herds per 100 herds at risk. Based on the 53 completed questionnaires, leptospirosis vaccination programs were not compliant with label directions in 36 of the 52 vaccinated herds: 69 (95% CI 55–81) of 100 herd managers that routinely vaccinated for leptospirosis did not comply with label directions. One herd was completely unvaccinated. Based on our findings, we estimate that approximately 10% of dairy farms in South-Western Victoria are likely to be infected with leptospirosis. While most herds are vaccinating for leptospirosis, most are not doing so according to label directions. We conclude that herd managers need to be better educated regarding leptospirosis vaccination programs.  相似文献   
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