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21.
Polymerase chain reaction/electrospray ionization-mass spectrometry (PCR/ESI-MS, previously known as "TIGER") utilizes PCR with broad-range primers to amplify products from a wide array of organisms within a taxonomic group, followed by analysis of PCR amplicons using mass spectrometry. Computer analysis of precise masses allows for calculations of base compositions for the broad-range PCR products, which can then be compared to a database for identification. PCR/ESI-MS has the benefits of PCR in sensitivity and high-throughput capacity, but also has the distinct advantage of being able to detect and identify organisms with no prior characterization or sequence data. Existing broad range PCR primers, designed with an emphasis on human pathogens, were tested for their ability to amplify DNA of well characterized phytobacterial strains, as well as to populate the existing PCR/ESI-MS bacterial database with base counts. In a blinded panel study, PCR/ESI-MS successfully identified 93% of unknown bacterial DNAs to the genus level and 73% to the species/subspecies level. Additionally, PCR/ESI-MS was capable of detecting and identifying multiple bacteria within the same sample. The sensitivity of PCR/ESI-MS was consistent with other PCR based assays, and the specificity varied depending on the bacterial species. Preliminary tests with real life samples demonstrate a high potential for using PCR/ESI-MS systems for agricultural diagnostic applications.  相似文献   
22.
The objectives of the present study were to quantify the effects of a biological chronic stressor (lameness) on the duration and frequency of different oestrous behaviours in parallel with milk hormone profiles. Dairy cows 51.8 ± 1.4 days postpartum (n = 59), including 18 non‐lame control cows, were scored for lameness and closely observed for signs of oestrus having had their follicular phases synchronized by administration of gonadotrophin‐releasing‐hormone (GnRH) followed by prostaglandin F (PG) 7 days later. Lameness shortened the period when herd‐mates attempted to mount the lame cows (1.83 ± 0.69 h vs 5.20 ± 1.53 h; p = 0.042) but did not affect the overall duration of total behaviours (lame 12.3 ± 1.3 h vs non‐lame 15.2 ± 1.3 h). Lameness also lowered the intensity of oestrus [1417 ± 206 points (n = 18) vs 2260 ± 307 points (n = 15); p = 0.029]. Throughout the synchronized oestrous period, lame cows mounted the rear of herd‐mates less frequently (p = 0.020) and tended to chin rest less (p = 0.075). Around the period of maximum oestrous intensity, lameness also diminished the proportion of cows mounting the rear of another cow and chin resting (p = 0.048, p = 0.037, respectively). Furthermore, lame cows had lower progesterone values during the 6 days before oestrous (p ≤ 0.05). Fewer lame cows were observed in oestrus following PG (non‐lame 83%, lame 53%; p = 0.030); however, if prior progesterone concentrations were elevated, lame cows were just as likely to be observed in oestrus. In conclusion, following endogenous progesterone exposure, lameness shortens the period when herd‐mates attempt to mount lame cows but does not affect the incidence of oestrous. However, lame cows are mounted less frequently and express oestrus of lower intensity. This is associated with lower progesterone prior to oestrus but not with abnormal oestradiol or cortisol profiles in daily milk samples.  相似文献   
23.
Susceptibility of cats to equine morbillivirus   总被引:7,自引:0,他引:7  
Objective To assess the susceptibility of cats to equine morbillivirus (EMV) by direct administration of the virus by subcutaneous, intra-nasal or oral routes, and following exposure to infected cats.
Design A disease transmission study, with controls, using ten cats.
Procedure Groups of cats were given the virus by the designated methods and assessed for evidence of infection by clinical examination, plus pathological and virological tests.
Results All cats administered the virus by subcutaneous, intra-nasal or oral routes became infected and developed the disease within 4 to 8 days. One of two cats in contact with affected cats also developed the disease, but two cats kept near to affected cats did not become infected. The virus was isolated from a range of tissues collected from the infected cats, and the lesions observed in affected cats were similar to those previously observed in horses naturally and experimentally infected with the virus.
Conclusion This is the first demonstration that animals can be infected with EMV by non-parenteral means, that the virus can transmit naturally between animals and confirms other reports of the similarity of EMV disease in horses and cats.  相似文献   
24.
SUMMARY: Records of 220 thoroughbred horses presented to the Randwick Equine Centre or the University of Queensland Veterinary Teaching Hospital for surgical management of carpal injury were reviewed. Details of racing performance were obtained, enabling evaluation of racing success following surgery. Age and sex matched control horses not known to have suffered carpal injury were selected from the Australian Stud Book and the Australian Racehorse Register. Control and treated populations were compared in terms of overall career racing success.
Radiographs or xeroradiographs from 198 horses were available for evaluation. The dorsomedial aspects of the distal articular surface of the radial carpal bone and the proximal articular surface of the third carpal bone were the most commonly observed locations of osteochondral fracture. Bilateral carpal injury was found to be sufficiently common to warrant routine radiographic examination of both limbs. The dorsolateral-palmaromedial oblique, flexed lateral and dorsoproximal-dorsodistal oblique (skyline) projections were the most useful views for evaluation of carpal degenerative joint disease. Surgical removal of osteochondral fractures by arthrotomy or arthroscopy was found to be a suitable method of treatment.
Arthroscopy was associated with a significantly shorter convalescent period than arthrotomy. Seventy-six percent of the treated population returned to racing following surgery. Average earnings following surgery were 20 000. However, the median value was only 1400 and 48% of the treated population failed to earn more than 1000. Male horses in both the treated and control groups performed significantly better than females. Treated horses performed significantly better than the randomly selected control population.  相似文献   
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27.

Aim

A prospective, observational study to determine the prevalence of post‐exercise conditions at Australian Greyhound race meetings and to assess association with race performance and other environmental, race‐ and dog‐related factors was undertaken.

Methods

A total of 4020 starters were observed (2813 Greyhounds, 1009 trainers, 536 races, 52 race meets, 48 race dates and 11 race tracks) following a race. The presence of diaphragmatic flutter (DF), ataxia, seizure, collapse or sudden death was recorded. Risk factors were screened by univariable logistic regression prior to multivariable backward stepwise model building.

Results

In this study, 962 starters (n = 768 dogs) had DF (23.9%), 16 starters were ataxic (0.4%) and there were no observed cases of collapse, seizure or sudden death. Race track location, increasing race distance, race grade based on increasing 1st place prize value, lower (earlier) race number at the meeting, age, a previous observation of DF at the last start, females, colour (white) and better finishing position were all associated with an increased risk of a Greyhound being observed with DF. However, when logistic regression assessing the random effect of dog was performed, the presence of previous DF was not significant. In this cohort, DF was common following strenuous exercise in Greyhounds and on its own does not appear to result in reduced performance or distress to the animal.

Conclusion

The incidence of ataxia was low and collapse, seizure and sudden death were not observed. However, even though uncommon, ataxia has welfare concerns for racing Greyhounds that warrants further investigation.  相似文献   
28.
To study the evolution of recombination rates in apes, we developed methodology to construct a fine-scale genetic map from high-throughput sequence data from 10 Western chimpanzees, Pan troglodytes verus. Compared to the human genetic map, broad-scale recombination rates tend to be conserved, but with exceptions, particularly in regions of chromosomal rearrangements and around the site of ancestral fusion in human chromosome 2. At fine scales, chimpanzee recombination is dominated by hotspots, which show no overlap with those of humans even though rates are similarly elevated around CpG islands and decreased within genes. The hotspot-specifying protein PRDM9 shows extensive variation among Western chimpanzees, and there is little evidence that any sequence motifs are enriched in hotspots. The contrasting locations of hotspots provide a natural experiment, which demonstrates the impact of recombination on base composition.  相似文献   
29.
Dairy bull sperm may be sex‐sorted, frozen and used to artificially inseminate heifers with acceptable fertility if the herd is well‐managed. One drawback to the technology is that donor bulls must be located within a short distance of the sorting facility in order to collect semen, which limits the number of bulls from which sorted sperm are available. A successful method used to overcome this limitation in sheep is sex‐sorting from frozen–thawed semen and refreezing for artificial insemination. This technique is attractive to the dairy industry, and therefore a series of three experiments was designed to investigate the optimal methods to prepare, sex‐sort and re‐freeze frozen–thawed bovine sperm. Sperm were prepared for sorting by density gradient separation in either PureSperm® or BoviPure?, followed by staining in one of three diluents (Androhep®, Bovine Sheath Fluid + 0.3% BSA or TALP buffer). Sperm were sorted and collected into Test yolk buffer, and frozen in an extender containing 0, 0.25, 0.375 or 0.5% Equex STM Paste. Frozen–thawed sperm were better orientated (p = 0.006) and had fewer damaged membranes (8.7 ± 0.6% vs 19.5 ± 2.4%; p = 0.003) after centrifugation in PureSperm® rather than BoviPure? gradients. Sperm orientation (p < 0.05) and motility (69.9 ± 3.0 vs 55.6 ± 4.0; p < 0.001) were highest after staining in Androhep® rather than in TALP buffer. Sperm were more motile (58.2 ± 4.7 vs 38.7 ± 3.5; p < 0.001) and had better acrosome integrity (74.3 ± 2.9 vs 66.8 ± 2.0; p < 0.001) after freezing in an extender containing 0.375% Equex STM Paste than in extender without Equex. Hence, a protocol has been developed to allow frozen–thawed bull sperm to be sex‐sorted with high resolution between the sexes, then re‐frozen and thawed with retention of motility and acrosome integrity.  相似文献   
30.
Repair of a type IV Monteggia fracture in a foal   总被引:1,自引:1,他引:0  
A Monteggia fracture is a humero-radial luxation combined with a fracture of the ulna. It is a rare injury, infrequently reported in the horse. This case report describes the surgical repair of such a fracture in a 4-month-old filly.  相似文献   
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