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101.
Cadaveric material has long been used to teach anatomy and more recently to train students in clinical skills. The aim of this study was to develop a systematic approach to compare the impact of four embalming solutions on the tissues of human cadavers. To this end, a formalin‐based solution, Thiel, Genelyn and Imperial College London soft‐preservation (ICL‐SP) solution were compared. The effect of these chemicals on the properties of the tissue was assessed by measuring the range of motion (ROM) of joints and measuring the dimensions of different structures on computed tomography (CT) images before and after embalming. The mean changes in the ratio (angle to ROM) differed statistically between embalming methods (Welch Statistic 3,1.672 = 67.213, p = 0.026). Thiel embalmed cadavers showed an increase in range of motion while ICL‐SP cadavers remained relatively the same. Genelyn and formalin embalmed cadavers registered a notable decrease in range of motion. Furthermore, investigation into the impact of the embalming chemicals on the dimensions of internal organs and vessels revealed that Thiel embalming technique leads to a decrease in the dimension of the cardiovascular system alone while formalin‐based solutions maintain the shape of the organs and vessels investigated. Our findings suggest that the joints of cadavers’ embalmed using ICL‐SP technique may faithfully mimic that of unembalmed cadavers and that formalin is necessary to retain shape and size of the organs and vessels investigated in this study. Despite this, a study with larger numbers of cadavers is required to confirm these findings.  相似文献   
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Twenty-seven of 427 Angora goats of mixed age became blind within a week of consuming large amounts of Stypandra glauca ("nodding blue lily"). A further 200 goats were depressed for several weeks, but most subsequently recovered. Blindness was associated with optic nerve neuropathy which is postulated to have followed compression of the optic nerves within the bony optic canals as a result of severe myelin oedema. Histologically, the intracanalicular portion of the optic nerve was sclerotic, while the intracranial portion of the optic nerve and the optic tracts were degenerating. The retrobulbar portion of the optic nerve was relatively unaffected. In addition, multifocal retinal photoreceptor degeneration was found ophthalmoscopically and histologically. The syndrome was not reproduced during a trial in which 2 goats were fed 4 and 20 kg of S. glauca harvested after it had finished flowering, more than 3 weeks after the first natural cases of blindness. Based on epidemiological and pathological data we propose that S. glauca is toxic to stock, but only for a short period while flowering in spring.  相似文献   
104.
Objective To assess the validity of claims that heavy metal contamination from an open-cut mine caused the death of 226 cattle on a nearby farm over a period of 18 months, and to investigate other possible contributing factors.
Procedure A retrospective assessment of previous investigations combinded with additional chemical analyses.
Results Extensive chemical analyses produced no evidence of heavy metal contamination associated with the mine. Analysis of bones indicated exposure to fluoride in greater than normal amounts. The main source of fluoride seems to have been gypsum that was included in a feed supplement and also ingested from fertiliser dumps on paddocks. The gypsum itself may have contributed significantly to the ill health. Other factors probably affected some classes of animals, notably the young calves.
Conclusions What originally seemed to be a disease problem of single aetiology probably was an expression of interacting multifactorial causes. This investigation has highlighted the potential toxicity of gypsum to livestock and the need for further studies to establish its basis.  相似文献   
105.
Bovine lymphotropic herpesvirus (BLHV) was detected for the first time in the UK in December 2005 in a dairy herd suffering from chronic, non-responsive post-partum metritis (NPPM). A small-scale investigation was undertaken in order to determine whether this was an isolated case. Samples of vaginal exudates or vaginal swabs were collected from cows in 13 UK dairy herds with a history of post-partum metritis that had not responded to standard treatment regimes for this condition. Cows in 9/13 herds and 1/13 herds were positive for BLHV and bovine herpesvirus-4, respectively, by pan-herpesvirus polymerase chain reaction. No consistent pattern of infectious agents or nutritional/metabolic factors commonly associated with post-partum metritis was observed at the times of sampling. The detection of BLHV in association with NPPM indicates that further work is warranted to determine the impact this virus has on cattle health.  相似文献   
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Infectious bovine rhinotracheitis (IBR), caused by bovine herpes virus 1 (BoHV-1), may result in various clinical consequences, including severe respiratory disease and conjunctivitis, venereal disease and reduced reproductive performance and abortion. This paper presents the serosurveillance findings from an intake of bulls into a performance testing station in Ireland during November 2007. The herd and within-herd BoHV-1 prevalence in 53 Irish beef herds and the risk factors for infection in these herds were determined, among bulls entering a beef performance testing station in Ireland. BoHV-1 status was determined for 41 herds, of which 30 (73.2%) herds were infected and the mean within-herd BoHV-1 prevalence was 28 (± 20)%. Multivariate exact logistic modelling revealed increasing numbers of contiguous herds and decreasing percentage of males within the herd as significant risk factors associated with infected herds. These findings highlight the high prevalence of BoHV-1 infection in those Irish beef herds that submitted bulls to this performance testing station, and raise concerns regarding IBR control nationally.  相似文献   
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Two dry-cow therapy products were evaluated in seven factory-supply dairy herds in the Waikato area. A product containing neomycin sulphate and the benzathine salt of penicillin (Neopen D.C. White; Smith-Biolab) was used in five herds, and one containing benzathine cloxacillin (Orbenin, Beecham) was used in two herds. Non-treated control cows were included in each herd. Both products were effective in eliminating intramammary infections with Staphylococcus aureus, Streptococcus uberis, and Streptococcus agalactiae. Efficacy of dry-cow therapy against S. aureus was 83.8% and 85.2% respectively. Spontaneous cure rate among controls was 30.8% for S. aureus during the dry period. Spontaneous cure rate for Str. uberis was 50%, while dry-cow therapy eliminated 100% and 77.8%, respectively, for the two products. Dry-cow therapy with either product eliminated more than 90% of Str. agalactiae infections while spontaneous cure rate was only 28.6%. These results further support the effectiveness of dry-cow therapy in reducing the level of subclinical mastitis in dairy herds by shortening the duration of intramammary infections.  相似文献   
110.
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