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91.
Listeria monocytogenes is a foodborne pathogen of major concern for public health in industrialised countries. Since L. monocytogenes carriage by pigs at the herd level could be a primary source for carcass contamination, control measures should be designed to reduce the L. monocytogenes load at the pre-harvest stage. For this purpose, an exploratory analytical survey was carried out in 2000-2001 in 93 French farrow-to-finish pig farms concerning L. monocytogenes contamination in pigs before they left for the slaughterhouse. On each farm, the L. monocytogenes status of a batch of contemporary fattening pigs housed in the same room was assessed on faecal material samples taken by means of gauze swabs wiped on the perianal region of the pigs. Fourteen percent of the batches studied had at least one contaminated sample and were therefore classified as L. monocytogenes contaminated batches. Two logistic regression models were used to assess the association between managerial and hygiene practices and the risk of L. monocytogenes contamination of the batch at the end of the finishing period on the whole data set (n = 93) and in the wet feeding farms only (n = 57). Wet feeding during the fattening period was identified as a risk factor for L. monocytogenes contamination. Risk factors related to the introduction of L. monocytogenes in pig facilities were identified for both the general and wet feeding farm data sets. Poor care paid to hygiene on the farms was found to increase the risk of being infected (boots cleaning, change room presence). When the duration of the empty period prior to the introduction of growing pigs was less than one day in the fattening section, the risk of L. monocytogenes contamination was significantly increased. For wet feeding farms, a distribution pipeline cleaning procedure including disinfection was found to be associated with a higher risk of contamination than no cleaning or a procedure consisting of rinsing with water only.  相似文献   
92.
Cloned pregnancies in cattle are considered to be at risk due to a variety of fetal or adnexal abnormalities. Data is lacking concerning the possibility of transabdominal ultrasonography in the assessment of these high risk pregnancies. Transabdominal ultrasonography has rarely been reported in the assessment of bovine cloned pregnancies. Ten Holstein heifers carrying 8-month-old cloned fetuses were assessed by transabdominal ultrasonographic examination during the 3rd trimester of pregnancy. Fetal heart rates (FHR), movements, adnexal appearance, and placentome size were recorded. The outcome of the pregnancies was also noted and potential indicators of fetal demise recorded. Survival rate 1 week after birth was 30%. Mean FHR was 113 beats per minute (range: 92 to 128 bpm) during the fetal ultrasonography. No correlation between FHR and fetal activity was found. Fetal hyperactivity and imaging of hyperechoic particles in both allantoic and amniotic fluids were possible signs of fetal distress. Despite the size of the fetus and the deep bovine abdomen, fetal transabdominal ultrasonography can be performed in cattle. This preliminary study points to the necessity of further larger studies for defining normal and abnormal findings in bovine late pregnancy.  相似文献   
93.
Peritonitis commonly is included in a list of differential diagnoses in food animal practice. Understanding the physiology of the ruminant peritoneal cavity and its response to injury is important to institute an adequate therapeutic plan. Ancillary procedures are used often and are necessary to confirm the diagnosis and should be well-organized.  相似文献   
94.
95.
Field investigations in 361 liver fluke infected cattle- or sheep-breeding farms on acid soil were carried out during thirty years in March and April to record indicator plants in relation to the category of site colonized by the intermediate host of liver fluke, the snail Galba truncatula. Seven types of snail zones and six species of indicator plants were recorded in the 7709 positive sites studied. The most frequent habitats were located at the peripheral extremities of open drainage furrows. Juncus acutiflorus, Juncus effusus, Glyceria fluitans, and Agrostis stolonifera were the indicator plants. Plant indicators were highly efficient (38-80% of variance explained) when used with the size of site area within a hydrographical zone. The identification of positive sites for G. truncatula is a key for controlling the intermediate host on pastures through biological control with predatory molluscs. The positive sites may be detected using a two-step method including first categorization of hydrographical zones and then, within a zone, use of one or several indicator plants (frequently J. acutiflorus).  相似文献   
96.
The aim of the present study was to evaluate the long-term clinical outcome for dogs with leishmaniasis that were treated with 3 different protocols: combined treatment with antimony and allopurinol, antimony alone, or allopurinol alone. Ninety-six dogs included in this study were determined to have leishmaniasis on the basis of (1) clinical features, (2) identification of the parasite in smears of lymph node, bone marrow aspirates, or skin biopsies, and (3) specific immunofluorescent assay. Three groups of dogs were defined: 45 dogs (group 1) were treated with antimony (100 mg/kg s.c. q24h) given concurrently for 1 month with allopurinol (15 mg/kg p.o. q12h), and then allopurinol alone for 8 months at the same dosage; 40 dogs (group 2) were treated with antimony alone according to the manufacturer's instructions (200 mg/kg s.c. q24h at 2-day intervals for 3-6 months); and 11 dogs (group 3) were treated with allopurinol alone (15 mg/kg p.o. q12h for 1-20 months). Information concerning signalment, history, physical examination findings, serologic testing and number of dogs becoming seronegative, outcome for each treated dog (clinical cure versus failure), and long-term survival were recorded. The numbers of the clinical cures versus failures were significantly different among the 3 groups (chi2 = 17.77, P < .001), between groups 1 and 2 (chi2 = 8.02, P < .01), between groups 2 and 3 (chi2 = 11.00, P < .01), and between groups 1 and 3 (chi2 = 16.52, P < .001). No significant difference between groups 1 and 2 was noted in the type of failure (relapse or death), serologic test results, and number of survival years (chi2 = 2.79, P > .05). The results of the present study indicate that antimony in combination with allopurinol produces better results than antimony alone or allopurinol alone for the treatment of the canine leishmaniasis. With combination treatment, duration of treatment with antimony is shorter and long-term administration of allopurinol is well tolerated.  相似文献   
97.
98.
Objective— To investigate the feasibility of, and outcome after, laparoscopic adrenalectomy in dogs with unilateral adrenocortical carcinoma.
Study Design— Case series.
Animals— Dogs (n=7) with Cushing's syndrome caused by unilateral adrenocortical carcinoma.
Methods— Laparoscopic adrenalectomy with the dog in lateral recumbency on the unaffected side. Three 5-mm portals (1 laparoscopic portal, 2 instrument portals) were placed in the paralumbar fossa. A fourth instrumental portal (5–12 mm) was placed above the kidney. After dissection and hemostatic control of the phrenicoabdominal vein, the adrenal gland was carefully dissected or when there was capsule fragility, necrotic content was partially aspirated. The remaining glandular tissue was removed through the 12-mm trocar site.
Results— Dogs with unilateral adrenocortical carcinoma (3 right-sided, 4 left-sided) without invasion of the caudal vena cava were successfully operated by laparoscopic approach. There were no significant intraoperative complications; 2 dogs died within 48 hours of surgery because of respiratory complications. Five dogs were discharged 72 hours after surgery, and signs of hyperadrenocorticism disappeared thereafter (survival time ranged from 7 to 25 months).
Conclusions— Laparoscopic adrenalectomy is feasible in dogs with either right- or left-sided adrenocortical carcinoma not involving the caudal vena cava.
Clinical Relevance— When performed by experienced surgeons, laparoscopic adrenalectomy offers a minimally invasive alternative to open laparotomy or retroperitoneal surgery for the treatment of unilateral adrenocortical carcinoma in dogs.  相似文献   
99.
100.
Mapping quantitative trait loci in plants is usually conducted using a population derived from a cross between two lines. The power of such QTL detection and mapping strategies and the estimation of the effects highly depend on the choice of the two parental lines. Thus, the QTL detected in such populations only represent a small part of the genetic architecture of the trait. Besides, the effects of only two alleles are characterized, which is of limited interest to the breeder. On the other hand, common pedigree breeding material remains unexploited for QTL mapping. From a pre-breeding perspective, the utilization of the good quality phenotypic data generated by breeders can be improved through the search and manipulation of QTL. The development of statistical techniques suitable for QTL mapping in general conventional breeding populations is thus challenging. In this study, we extend QTL mapping methodology to a generalized framework, based on a two-step IBD variance component approach, applicable to any type of breeding population coming from inbred parents. The proposed developments attempt to make full use of any inferable relatedness information between the parents. The power and accuracy of this method were assessed on simulated data mimicking conventional breeding programs in cereals, in an effort to reproduce actual conditions of marker and gene allelic frequencies across the parental lines. A wide range of breeding scenarios and of genetic architectures was explored. We demonstrated that taking into account the estimable relatedness between the parents significantly improved the power and accuracy of the QTL parameter estimations. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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