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Indirect evidence is presented that human disturbances are having a profound effect on reproductive efforts of Larus occidentalis livens at several colonies in the Gulf of California. Breeding adults that lose their eggs or chicks apparently practise conspecific predation whether or not humans are present, thus increasing effects of human intrusions. These combined effects could lead to a severe decline in numbers or even pose a threat to the survival of this endemic population, if human disturbance is widespread. Attempts to assess breeding success throughout the Gulf seem warranted and, if necessary, some action to regulate human contact may be essential.  相似文献   
3.
Streptococcus (S.) suis plays an important role in pig breeding causing invasive diseases such as meningitis and polyarthritis. Herd problems with Streptococcus suis are common in many pig farms and are frequently characterised by disease outbreaks. In this context, it is often important to identify chains of infection, e.g. between a farrow-to-wean and a grower farm. In the following case report a possible chain of infection among the different farms of a farrow-to-finish system was investigated. In two grower units herd problems with S. suis were present; the mortality was higher than 5 %. It appeared likely, that the streptococci causing these problems were transmitted from a single farrow-to-wean unit to the two different grower farms. In the respective farms swabs were taken from different healthy animals and, in the case of the grower farms, also from the infected animals. Genotypic profiling of strains by a multiplex-PCR and AFLP typing method revealed that two different S. suis pathotypes were responsible for the herd problems. Both pathotypes could not be detected in the farrow-to-wean farm.Thus, a chain of infection originating from the farrow-to-wean farm appeared unlikely. The multiplex PCR was in this case sufficient to elucidate the described problem.  相似文献   
4.
The objective of this retrospective study was to determine the occurrence of joint-related complications after elective arthroscopy of the tibiotarsal joint (TTJ) in 329 horses, and the association with specific clinical parameters. Data were collected from medical records of horses undergoing elective tibiotarsal joint arthroscopy for fragment removal. Exact conditional univariate regression was used to determine significant risk factors for joint-related post-operative complications.Of 485 joints, 2 (0.4%) developed surgical site infection, 4 (0.8%) developed septic arthritis, 1 (0.2%) developed synovial fistula. There was a significantly increased odds of having septic arthritis as height and length of the distal intermediate ridge of the tibia (DIRT) lesion increased. The median height and length of the DIRT fragments in affected cases was 13.5 mm and 18.0 mm, respectively. For each unit (1 mm) increase in height, there was a 42% increase in the risk of septic arthritis occurrence (P = 0.0042), and a 15% increase for each unit increase in length (P = 0.035). Horses were significantly less likely to develop septic arthritis when suture smaller than USP 0 was used.Horses with larger osteochondritis dissecans lesions of the DIRT region have an increased risk of developing septic arthritis following fragment removal.  相似文献   
5.
Pre-harvest sprouting (PHS) causes significant yield loss and degrade the end-use quality of wheat, especially in regions with prolonged wet weather during the harvesting season. Unfortunately, the gene pool of Triticum durum (tetraploid durum wheat) has narrow genetic base for PHS resistance. Therefore, finding out new genetic resources from other wheat species to develop PHS resistance in durum wheat is of importance. A major PHS resistance QTL, Qphs.sicau-3B.1, was mapped on chromosome 3BL in a recombinant inbred line population derived from ‘CSCR6’ (Triticum spelta), a PHS resistant hexaploid wheat and ‘Lang’, a PHS susceptible Australian hexaploid wheat cultivar. This QTL, Qphs.sicau-3B.1, is positioned between DArT marker wPt-3107 and wPt-6785. Two SCAR markers (Ph3B.1 and Ph3B.2) were developed to track this major QTL and were used to assay a BC2F8 tetraploid population derived from a cross between the durum wheat ‘Bellaroi’ (PHS susceptible) and ‘CSCR6’ (PHS resistant). Phenotypic assay and marker-assisted selection revealed five stable tetraploid lines were highly PHS resistant. This study has successfully established that PHS-resistance QTL from hexaploid wheat could be efficiently introgressed into tetraploid durum wheat. This tetraploid wheat germplasm could be useful in developing PHS resistant durum cultivars with higher yield and good end-use quality.  相似文献   
6.
A domestic shorthair cat was presented for lethargy and ataxia. Clinical findings included an abdominal mass, lumbosacral pain, ataxia. Aspirates from the liver and lymph nodes revealed intracellular, negative-staining rods. Treatment for presumptive mycobacterium infection was unsuccessful and the cat was euthanized. Disseminated Mycobacterium avium was confirmed on culture.  相似文献   
7.
Xiphinema diversicaudatum and X. index are vector nematode species of economic importance in viticulture regions as they can transmit Arabis Mosaic, Grapevine Fanleaf and Strawberry Latent Ringspot viruses to grapevine. Wang et al. (2003) designed species-specific diagnostic primers from ribosomal genes for both these vector species as well as a vector and a non-vector species X. italiae and X. vuittenezi, respectively. Our study aimed to confirm the specificity and determine the sensitivity and reliability of the primers for the two vector species, X. diversicaudatumand X. indexwhen challenged with closely related longidorid species and general nematode communities typical of vineyard soil. With one exception, no PCR product was observed when the primers were tested against six Longidorus, one Paralongidorus and one Xiphinema non-target species. Occasionally (three out of eight replicate PCR reactions) a weak PCR product was noted when primers for X. index were tested with L. elongatus. Furthermore, when challenged with a range of non-target nematode species comprising the nematode community typical of viticulture soil, no PCR product was amplified. An experimental dilution series of extracted DNA rigorously demonstrated that DNA from an equivalent single specimen of the target virus-vector species, X. diversicaudatum and/or X. index, could be detected amongst 1000 equivalent non-targetX. vuittenezi. Also, extracted DNA from an equivalent single target specimen was detected when added to DNA extracted from the overall soil nematode community. The primers were assessed further by using serial mixtures of actual nematodes rather than extracted DNA to simulate field soil. Using this method, a single target nematode could be detected amongst 200 non-target specimens. Given their specificity, sensitivity and reliability, it appears that these diagnostic primers will be of great benefit to phytosanitary/quarantine services related to the viticulture industry.  相似文献   
8.
A 6-year retrospective study (2000–2005) of animals slaughtered at the Zango abattoir in Zaria, Kaduna State, Nigeria was carried out to determine disease conditions encountered in slaughtered animals. Records kept at the abattoir were analysed. A total of 69,307 cattle, 3,820 goats and 1,763 sheep were slaughtered for the period under study. Of the 69,307 cattle slaughtered for the period, 22,459 (32.41%) were males and 46,848 (67.59%) were females, while 1,763 sheep were slaughtered comprising of 506 (28.70%) males and 1,257 (71.30%) females, and 3,820 goats made up of 1,212 (31.73%) males and 2,608 (68.27%) were females. The major disease and/or pathological conditions were helminthosis (fascioliasis, haemonchosis and paramphistomosis) 16.20%, Streptothricosis 4.15%, Pericarditis 2.20%, liver cirrhosis 2.08%, abscesses 1.04%, pneumonia 0.14%, nephritis 0.05% and Contagious Bovine Pleuropneumonia, Tuberculosis and Nocardiosis 0.01% each. Out of the 15,075 infected organs, 13,314 (88.38%) were partially salvaged while 1,751 (11.6%) whole organs were condemned. A total of 1,239 pregnant cows, 221 pregnant ewes and 637 pregnant does were slaughtered, representing a foetal wastage of 2.65% for cattle, 17.58% for sheep and 24.43% for goats. The result of this study apart from serving as an indicator of field disease condition also demonstrates cases of serious losses in production due to slaughter of pregnant animals especially for sheep and goats.  相似文献   
9.
The present study confirms that following infection with the ectoparasitic sheep scab mite, Psoroptes ovis, there is a rapid (within 24 h) inflammatory influx of eosinophils and apoptosis of the keratinocytes at the site of infection. In order to investigate whether these inflammatory reactions are important in the maintenance of mite infection, a group of animals were treated daily after the establishment of infection with the potent anti-inflammatory drug, Cyclosporin A. The course of infection was monitored by determining the lesion area and mite numbers, systemic antibody and blood eosinophils, as well as the inflammatory cells and T cell sub-populations within the lesion throughout the 6-week duration of the experiment. These parameters were compared with those in a similar infected control (non-treated) group. In control infected animals, the lesion area and mite numbers increased steadily throughout the 6-week period. In contrast, lesion area and mite numbers were severely depressed in the group which received Cyclosporin A. Local and systemic eosinophils, and systemic antibody were also significantly reduced in the drug treated animals, compared to controls. Surprisingly however, the number of lesional pan T cells, T helper cells, gammadeltaT cells and dendritic cells in Cyclosporin A treated animals were either the same, or significantly (P < 0.05) enhanced when compared to the control infected animals at the termination of the experiment. The results will be discussed in terms of the role of the dermal inflammatory response in the establishment and maintenance of the sheep scab mite.  相似文献   
10.
Following the hypothesis that metabolic screens may be useful tools in the diagnosis of canine aggression we have investigated the blood plasma amino acid levels of dogs which have been found aggressive (N = 10) against dogs or men in comparison to non-aggressive dogs (N = 10). In summary, the aggressive dogs showed elevated plasma concentrations of the neurophysiological active aromatic amino acids tryptophan (46/171 micromol/l, p < 0,001), tyrosine (38/67 micromol/l, p < 0.01) and histidine (74/91 micromol/l, p < 0.01) and lower lysine concentrations (175/151 micromol/l, p < 0.05), which seems to point to a stress situation of these dogs. The nitrogen metabolism is impaired in the urea-cycle in the conversion of ornithine (17/34 micromol/l, p < 0.01) to citrulline (64/47 micromol/l). Higher levels of branched chain amino acids, especially leucine (122/150 micromol/l, p < 0.01), mainly metabolized in muscles, and isoleucin (60/71 micromol/l, p < 0.05) show a high energy potential.The acidose-stimulator methionine (48/78 micromol/l, p < 0.01) proved elevated. The results show that the changed behavior in the aggressive dogs is also reflected in their free amino acid plasma concentrations, independent of the question whether these data are the cause or the result of the aggressivity.  相似文献   
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