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1.
Tuberculosis in wild seals and characterisation of the seal bacillus   总被引:3,自引:0,他引:3  
SUMMARY Tuberculosis was diagnosed in 3 otariid seals found dead on beaches at 3 locations on the south coast of Western Australian between May 1990 and March 1991. This confirms that tuberculosis is present in the 2 native seals (Neophoca cinerea and Arctocephalus forsteri) in Western Australian waters. Mycobacterium sp isolated from the lungs of 2 of the seals were studied to determine the similarity of the strains to each other, to the strains isolated during 1986 from Australian sea lions and New Zealand fur seals kept in captivity at a marine park near Perth, Western Australia, and to a strain isolated in 1988 from a seal trainer who worked with the infected captive seals for 3 years. After restriction endonuclease analysis (REA) with the endonucleases Bst Ell, Bcl I and Pvu II, one of the wild seal strains appeared to have identical DNA fragment patterns to the strains from the captive seals and the seal trainer. The other wild seal isolate had identical REA profiles using Bst EII and Bcl I, but a minor difference was detected using Pvu II. Differences in these isolates were more clearly seen in restriction fragment length polymorphisms after hybridisation with two DNA probes. The secretory protein MPB70, present in M bovis, was not detected in wild seal isolates using sodium dodecyl sulphate polyacrylamide gel electrophoresis and Western blotting techniques. Analysis of protein and DNA fragment profiles indicated that seal tuberculosis isolates form a unique cluster within the M tuberculosis complex.  相似文献   
2.
The following compounds of milk from Indian-Rhino (Rhinoceros unicorns) were examined: water-, fat-, protein-, potassium-, sodium-, calcium-content. Besides this we analyzed by gas-Liquid chromatography the short-chain and the long-chain fatty-acids.  相似文献   
3.
Correlations among selected pork quality traits   总被引:15,自引:0,他引:15  
Establishing relationships among specific quality traits is important if significant progress toward developing improved pork quality is to be realized. As part of a study to examine the individual effects of genes on meat quality traits in pigs, a three-generation resource family was developed. Two Berkshire sires and nine Yorkshire dams were used to produce nine F1 litters. Sixty-five matings were made from the F1 litters to produce four sets of F2 offspring, for a total of 525 F2 animals used in the study. These F2 animals were slaughtered at a commercial facility upon reaching approximately 110 kg. Carcass composition traits, pH measurements, and subjective quality scores were made at 24 h postmortem. Loin samples (n = 525) were collected at 48 h postmortem, and meat quality traits were evaluated. These traits included pH (48 h), Hunter L-values, drip loss, glycolytic potential, ratio of type IIa/IIb myosin heavy chains (IIa/IIb), total lipid, instrumental measures of tenderness using the Star Probe attachment of the Instron, cook loss measurements, and sensory evaluations. Significant phenotypic correlations were found between many carcass, instrumental, and biochemical measurements, and sensory quality traits. Star Probe measurements were significantly correlated with drip loss (0.29), glycolytic potential (0.30), pH (-0.29), total lipid (-0.14), and Hunter L-values (0.28). Drip loss was significantly correlated with glycolytic potential (0.36), pH (-0.28), IIa/IIb (-0.10), and Hunter L-values (0.33). Hunter L-values were also significantly correlated with total lipid (0.33) and IIa/ IIb (-0.11). Sensory tenderness, flavor, and off-flavor scores were significantly correlated with drip loss, pH, and glycolytic potential measurements. Marbling score, total lipid, and drip loss were not significantly correlated with sensory juiciness scores, but cooking loss was. Marbling and total lipid were significantly correlated with firmness scores (0.37 and 0.31, respectively). Taken together, the data in this study suggest that changes in some meat quality traits can affect many other meat quality attributes. The correlations yield information that could aid in directing future studies aimed at understanding the underlying biological mechanisms behind the development of many quality traits.  相似文献   
4.
Zoonotic cutaneous leishmaniasis (ZCL), a vector‐borne disease, poses serious psychological as well as social and economic burden to many rural areas of Iran. The main objectives of this study were to analyse yearly spatial distribution and the possible spatial and spatio‐temporal clusters of the disease to better understand spatio‐temporal epidemiological aspects of ZCL in rural areas of an endemic province, located in north‐east of Iran. Cross‐sectional survey was performed on 2983 recorded cases during the period of 2010–2012 at village level throughout the study area. Global clustering methods including the average nearest‐neighbour distance, Moran's I, general G indices and Ripley's K‐function were applied to investigate the annual spatial distribution of the existing point patterns. Presence of spatial and spatio‐temporal clusters was investigated using the spatial and space–time scan statistics. For each year, semivariogram analysis and all global clustering methods indicated meaningful persistent spatial autocorrelation and highly clustered distribution of ZCL, respectively. Eight significant spatial clusters, mainly located in north and northeast of the province, and one space–time cluster, observed in northern part of the province and during the period of September 2010–November 2010, were detected. Comparison of the location of ZCL clusters with environmental conditions of the study area showed that 97.8% of cases in clusters were located at low altitudes below 725 m above sea level with predominantly arid and semi‐arid climates and poor socio‐economic conditions. The identified clusters highlight high‐risk areas requiring special plans and resources for more close monitoring and control of the disease.  相似文献   
5.
Genetic Resources and Crop Evolution - Brassica napus L is an important oilseed crops grown throughout many parts of the world. It is well adapted to long day photoperiods. Synthetic B. napus was...  相似文献   
6.
Urban and industrial air pollution can cause elevated heritable mutation rates in birds and rodents. The relative importance of airborne particulate matter versus gas-phase substances in causing these genetic effects under ambient conditions has been unclear. Here we show that high-efficiency particulate-air (HEPA) filtration of ambient air significantly reduced heritable mutation rates at repetitive DNA loci in laboratory mice housed outdoors near a major highway and two integrated steel mills. These findings implicate exposure to airborne particulate matter as a principal factor contributing to elevated mutation rates in sentinel mice and add to accumulating evidence that air pollution may pose genetic risks to humans and wildlife.  相似文献   
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Placement of markers on anatomical landmarks represents a large source of error in three-dimensional kinematics. Our objectives were to test the accuracy and precision of a custom-made pointer and compare it to conventional skin markers in dogs. The pointer was first assessed by pointing at the surface of a spherical marker of known dimensions and position in space. Secondly, a point located cranio-distally to the lateral epicondyle was marked in 12 canine elbows with a Steinmann pin and reflective markers. Ability to locate a landmark was compared between the pointer and skin-mounted marker. The distance between experimental and true locations was compared between the two methods. A sphere was mathematically fitted through 29 collected points on the spherical marker. Centre, diameter and volume overlap of the fitted sphere were compared to that of the marker. A 0.729 mm bias was found indicating good accuracy. Residual values were small indicating good precision. The average distance between the true and experimental position of the anatomical landmarks were 9.55 ± 4.20 mm and 9.32 ± 3.28 mm for the pointer and the marker respectively. No significant differences were observed between the two methods. The pointer proved to be accurate and reliable for localizing virtual points and was at least equivalent to skin mounted markers for the detection of anatomical landmarks in the dog. It should prove useful in the localization of anatomical landmarks for kinematic analysis.  相似文献   
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Dual choice bioassays were used to evaluate the antifeedant property of essential oil and methanolic extract of Alpinia galanga (L.) (locally known as lengkuas) against two species of termites, Coptotermes gestroi (Wasmann) and Coptotermes curvignathus (Holmgren) (Isoptera: Rhinotermitidae). A 4-cm-diameter paper disc treated with A. galanga essential oil and another treated with either methanol or hexane as control were placed in a petri dish with 10 termites. Mean consumption of paper discs (miligram) treated with 2,000 ppm of essential oil by C. gestroi was 3.30 ± 0.24 mg and by C. curvignathus was 3.32 ± 0.24 mg. A. galanga essential oil showed significant difference in antifeedant effect, 2,000 ppm of A. galanga essential oil was considered to be the optimum concentration that gave maximum antifeedant effect. The essential oil composition was determined using gas chromatography-mass spectrometry. The major component of the essential oil was 1,8-cineol (61.9%). Antifeedant bioassay using 500 ppm of 1,8-cineol showed significant reduction in paper consumption by both termite species. Thus, the bioactive agent in A. galangal essential oil causing antifeeding activity was identified as 1,8-cineol. Repellent activity shows that 250 ppm of 1,8-cineol caused 50.00 ± 4.47% repellency for C. gestroi, whereas for C. curvignathus 750 ppm of 1,8-cineol was needed to cause similar repellent activity (56.67 ± 3.33%). C. curvignathus is more susceptible compare to C. gestroi in Contact Toxicity study, the lethal dose (LD50) of C. curvignathus was 945 mg/kg, whereas LD50 value for C. gestroi was 1,102 mg/kg. Hence 1,8-cineol may be developed as an alternative control against termite in sustainable agriculture practices.  相似文献   
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