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971.
The aim of this study is to assess the risk of contamination by Salmonella Typhimurium of pigs by nose-to-nose contact or the airborne route. Thirty twelve-week-old SPF pigs were divided into 4 groups housed in 4 different rooms: the first room contained Salmonella-free control pigs (n = 4), the second room had 10(3) CFU S. Typhimurium inoculated pigs (n = 5) and non-inoculated "contact" pigs (n = 4), the third room had pigs (n = 8) receiving potentially contaminated air from the following room through a hole (4 pigs housed in the pen situated near the hole and 4 pigs in the pen at the opposite side of the room), and the fourth room had pigs (n = 5) inoculated with 10(6) CFU Salmonella Typhimurium and also non inoculated "contact" pigs (n = 4). The "contact" and the inoculated pigs were housed in adjacent pens allowing nose-to-nose contact. The 5 pigs orally inoculated with 10(6) CFU S. Typhimurium were bacteriologically and serologically positive 1 week later and their environment was contaminated as early as 1 day pi. The faecal samples of 4 nose-to-nose contact pigs were bacteriologically positive and one of them was seropositive 5 weeks pi before the pigs were commingled. The 8 pigs housed in the third room received S. Typhimurium by an active airflow coming from the contaminated room (1000 m3/hour). Their faecal samples remained negative until 8 weeks pi but the environmental swabs taken in the room close to the airinlet were contaminated 2 days pi and positive swabs were found elsewhere in the room 5 weeks pi. Two seropositive pigs were encountered 8 weeks pi in the pen situated near the hole. Only one among the 5 pigs inoculated with 10(3) CFU had bacteriologically positive faeces 1-week pi and the 4 pigs kept in nose-to-nose contact with them remained negative. A dose of 10(3) CFU was too small to induce persistent excretion and to stimulate a humoral immune response. However, the dose of 10(6) CFU induced contamination of nose-to-nose contact pigs and contamination of the environment by airflow.  相似文献   
972.
REASONS FOR PERFORMING STUDY: Disorders of the equine sphenopalatine sinus, including empyema and neoplasia, have been reported to cause damage to cranial nerves II and V. However, the clinical anatomy of these sinuses is not well described in horses. OBJECTIVE: To examine the anatomy of the sphenopalatine sinuses in a range of equidae and, in particular, to examine the relationship of these sinuses to adjacent major nerves and vessels. METHODS: The anatomy of the sphenoidal and palatine paranasal sinuses was examined in 16 equidae, primarily using transverse skull sections. Relevant structures were documented and photographed. RESULTS: There was much variation between individual horses in sphenopalatine sinus anatomy. The sphenoidal sinuses were small in young horses and appeared to become larger and more complex with age. Variation was present in the extent that the sphenopalatine sinus extended into the basisphenoid bone. The septum dividing left and right sphenoidal sinuses was frequently not midline, but was intact in all cases. The sphenoidal and palatine sinuses communicated in most horses. In such cases, what could accurately be termed the (combined) sphenopalatine sinuses usually drained directly into the caudal maxillary sinuses. Additionally, in 5 out of 16 cases, some compartments of the sphenoidal sinus also drained into the ethmoidal sinus. The dorsal and lateral walls of the sphenoidal sinus were very thin and directly adjacent to cranial nerves II, III, IV, V and VI and major blood vessels. CONCLUSIONS: The equine sphenoidal and palatine sinuses are very variable in their anatomy, but are always in close proximity to multiple cranial nerves and major blood vessels. POTENTIAL RELEVANCE: Many cranial nerves and blood vessels could be damaged with disorders involving the sphenopalatine sinus, potentially causing major and variable neurological syndromes, haemorrhage and extension of sepsis.  相似文献   
973.
The prevalence of subclinical hepatitis was investigated in a group of 106 randomly selected 3-year-old Doberman Pinschers. Histopathologic examination of liver samples from 65 dogs (52 dogs with high bile acids, alkaline phosphatase activity, or alanine aminotransferase activity or with copper granules in hepatocytes in a liver aspirate and 13 normal dogs) revealed subclinical hepatitis in 22 dogs (19 females and 3 males). Liver copper concentrations measured by instrumental neutron activation analysis was significantly higher (mean +/- SD; 419 +/- 414 microg/g dry matter) in dogs with hepatitis than those without liver disease (197 +/- 113 microg/g; P = .0008). At 2.6 +/- 0.6 years hepatitis persisted in 5 of 16 dogs available for examination. One dog with a high copper concentration but normal liver subsequently developed subclinical hepatitis after 3 years. During the follow-up period, the average copper concentration of the 6 dogs with persistent subclinical hepatitis was 939 +/- 299 microg/g and had continued to rise significantly (P = .02). The hepatitis in these dogs was associated with apoptotic hepatocytes and copper-laden Kupffer cells in centrolobular regions. The results of this study suggest that there is a relationship among copper storage, hepatocellular damage, and hepatitis in Doberman Pinschers.  相似文献   
974.
975.
1. A 28-d experiment was conducted to evaluate the effects of fumonisin B1 (FB1) on egg production and egg quality of young laying Japanese quail fed on fumonisin-contaminated rations. 2. To this end, 128 7-week-old birds were randomly distributed into 4 experimental groups (32 birds per group) and given rations containing 0 (control), 10, 50 and 250mg FB1/kg feed. Each treatment consisted of 4 replicates of 8 quail. Egg production and egg weight were checked daily. Feed consumption and feed conversion were determined weekly. Eggs laid on the last day of each 7-d period were collected and subjected to individual analysis for specific gravity, Haugh units and percentage eggshell. 3. Compared with controls, quail given > or = 50 mg FB1/kg had reduced feed intake and lower body weight gain. Feed conversion was reduced only in birds given 250 mg FB1/kg. 4. Mean egg production and egg weight were lower in birds given 250mg FB1/kg. Eggshell weight was reduced in birds given > or =50mg FB1/kg. However, mean specific gravity, Haugh units and percentage eggshell were not affected by FB1. 5. No histopathological changes were observed in liver, kidney or heart samples from any treatment group. 6. The results indicated that exposure to FB1 at concentrations > or = 50 mg/kg could adversely affect quail performance, emphasising the importance of controlling fumonisin contamination of quail rations.  相似文献   
976.
Six cats with an advanced stage squamous cell carcinoma (SCC) of the nasal planum were treated with a combination of superficial radiotherapy and intralesional carboplatin therapy. This multimodality protocol was well tolerated by the majority of cats and resulted in complete responses in all cats (100%). Median follow‐up for all cats is 268 days, and the median time‐to‐recurrence, time‐to‐progression and overall survival have not yet been reached. Our study, although limited in number of animals and with a relatively short median follow‐up compared to other studies for this disease, suggests that a combination of radiotherapy and intralesional carboplatin is a useful treatment option for an advanced stage SCC of the nasal planum in cats and warrants further application of the multimodality approach presented here.  相似文献   
977.
Two previously identified single-nucleotide polymorphism markers located within the micromolar calcium-activated neutral protease gene (CAPN1) were evaluated for their association with variation in meat tenderness using one commercial sample of Simmental x Angus crossbred calves and one multibreed, crossbred research herd. The commercial sample included 362 animals sired by 23 registered Simmental bulls bred to unregistered Angus cows and represented current industry animals in which to test the predictive merit of the markers. The second sample was a research herd including 564 steers from the Germplasm Evaluation Cycle VII population at the U.S. Meat Animal Research Center, produced with semen from popular sires of the seven Bos taurus beef breeds with the most registrations in the United States (Angus, Charolais, Gelbvieh, Hereford, Limousin, Red Angus, and Simmental) on Angus, Hereford, and MARC III cows. These animals form a relatively outbred population that constituted a stringent test of the predictive merit of the genetic markers, although small groups were half-sibs. Warner-Bratzler shear force measurements were used to determine tenderness phenotypes for all animals. The populations were genotyped for two markers that predict variation at amino acid positions 316 and 530 of the mu-calpain polypeptide, produced by the CAPN1 gene. Minor allele frequencies for markers 316 and 530 in the commercial sample were 0.17 and 0.37, respectively, and in the Cycle VII animals, were 0.20 and 0.28, respectively. Both markers showed association with shear force in the commercial sample (P = 0.04) and the Cycle VII population (P = 0.02), supporting the hypothesis that they represent potential markers to aid selection for improved meat tenderness in commercial populations of beef cattle in the United States.  相似文献   
978.
The economic impact of different extension messages used was calculated using enterprise budgeting (gross margin analysis). Input data were gleaned from the literature, from participatory appraisals, as well as a field study, spanning 12 months, of small-scale communal goat farming systems in Jericho in the Odi District of North West Province. The number of offspring weaned per annum, as a proportion of does owned, was selected as the desired output for analysis. This study has shown that small-scale communal goat farmers are not adopting or implementing extension messages to improve production capacity. In South Africa the majority of goats are slaughtered in the informal sector. If the informal sector is to be persuaded to market goats commercially through formal channels, then knowledge of the economics of goat farming on communal lands should be provided. The economic aspects of extension messages are probably an important factor in determining acceptance and sustainability yet appear to be seldom investigated. The probable reason for lack of adoption of standard extension messages, which promote improved nutrition, parasite control, vaccination and treatment of goats, was economic. In other words, the so-called 'poor management practices' used by communal farmers appeared to be economically more profitable than the 'good management practices' suggested to increase production. The price of communal goats was not related to their mass. A higher level of inputs would probably have resulted in a heavier kid, however it was established that this would not have influenced the price received as a majority of the goats were slaughtered for ritual purposes where age, colour and sex were more important to the purchaser than body mass. It is standard practice in commercial farming systems to evaluate the economic benefits of all management practices before they are implemented. Production animal veterinarians use veterinary economics to compare different scenarios to control diseases or select management practices in commercial herds. It is suggested that the inputs and outputs of small-scale farming systems should be carefully analysed and that veterinary economics should also be used to evaluate the probable impact of extension messages formulated by veterinarians and animal health technicians.  相似文献   
979.
The complete archive of the New Zealand Veterinary Journal went online on 1 January 2003 on SciQuest (www.sciquest.org.nz), an innovative new e-publishing website developed by the New Zealand Veterinary Association (NZVA). This follows hot on the heels of the CD-Rom version released from the same platform in June last year. Subscribers in 2003 will be able to search and retrieve, online, the full text of any article published in the journal since its inception in 1952. To date, few veterinary science journals are able to offer such a complete and comprehensive resource. SciQuest's mission is to provide high-speed access to science and continuing education articles to scientists and veterinarians in a fully indexed and searchable format, both online (via the internet) and offline (via CD-Rom). Searching and browsing the archive online is free and abstracts are available for all articles published from 1972 onwards. Access to full text, which is presented in PDF format exactly as published, is restricted to journal subscribers. The site will be updated with each issue of the journal as it is published. The online format will largely suit institutional users and casual enquiries, whereas the offline version is designed to be loaded onto computer hard drives for immediate access, any-time, and is better suited to frequent users and veterinary practitioners. A major advantage of the offline resource is its speed and immediacy, returning search results and full text much faster than the online version, without the need for internet access. The search engine has been designed to suit specific problem-oriented enquiries, and great effort has been expended to ensure the archive is both complete and accurate. The same search engine and interface has been provided on both versions, which allows for fast and highly specific searching of titles and full text of all articles for the occurrence of any word or combinations of words, as well as indexes of author, volume, year, article type, animal type and subject. Search results can be instantly sorted by author and date of publication, and powerful secondary search features such as 'by the same author', 'in the same issue' and 'same subject' links add power and flexibility. The offline version will be updated with annual releases and is available for purchase to subscribers and members of the NZVA.  相似文献   
980.
The influence of 0, 60 or 120 min access to a grove of either Ziziphus mauritiana (Ziziphus) or Combretum aculeatum (Combretum) on forage intake and on the digestibility, growth and excretion of nutrients was determined using 40 Oudah rams grazing for 7 h/day on poor-quality dry season pasture in the Sahel. The effects of browse species and browsing duration (0, 30, 60 or 120 min) on the ruminal ammonia content were also evaluated using 8 mature fistulated rams. Ziziphus increased both total digestible organic matter and total dry matter intakes per (kg live weight)0.75 without decreasing herbage intake, whereas 60 or 120 min access to Combretum reduced herbage intake by 6.3% and 4.2%, respectively. The digestibility of the diet decreased (p<0.05) with the duration of access to the groves. Despite the provision of more nitrogen (N) than in the control diet, ruminal NH3-N decreased 24 h after browsing commenced. The reduced live weight gain of sheep browsing Combretum may indicate more deleterious compounds in Combretum than in Ziziphus. Ziziphus appears to have more potential than Combretum to increase sheep production in low-input crop/livestock systems.  相似文献   
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