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1.
First-fortnight incidence (FFI) is a modelling parameter that can be used to predict both the prevalence and duration of a foot-and-mouth disease (FMD) epidemic at regional and national levels. With an indication of how long an epidemic may last by the end of week two, it becomes possible to estimate whether vaccination would be economically viable from the start of an epidemic. Where FFI indicates that an epidemic is unlikely to last for as long as an export ban on agricultural produce, it may be inappropriate to implement a policy of 'vaccination to live'. Alternatively where FFI indicates that an epidemic will equal or exceed the ban length, then the benefits of vaccination should be considered at an early stage, during or after the first fortnight. Since blanket vaccination of the national or regional herds and flocks would be both costly and heighten the risk of producing carrier animals, targetting vaccination through risk assessment becomes useful.  相似文献   

2.
Half-pin (type 1) external skeletal fixators with four, three, and two fixation pins and an intramedullary pin, and four-pin external skeletal fixators without an intramedullary pin were applied to prepared canine femurs. Load to failure, load to yield, safe load, and stiffness under compressive and torsional loads were calculated. When tested in compression, all measurements for the four-pin fixators with an intramedullary pin were significantly higher than for the two-pin fixators with an intramedullary pin. The values for all parameters except load to yield were significantly higher for the four-pin fixators with an intramedullary pin than for the four-pin fixators without an intramedullary pin. When tested in torsion, all measurements for the four-pin fixators with an intramedullary pin were significantly higher than for the two or three-pin fixators with an intramedullary pin.  相似文献   

3.
The savanna fauna of treefrogs in East Africa includes five distributional patterns: a widely distributed element, an element in the savanna north of the central forest from Cameroun to northern East Africa, an element south of the central forest, an East African lowland fauna, and an element in the dry savanna of Kenya and northern Tanzania.

The forest fauna includes two elements: a western element connected with the Congo Forest block and an eastern element with a distribution similar to the East African lowland savanna fauna.  相似文献   

4.
发达的畜牧业是现代农业的重要标志,也是推进社会主义新农村建设的重要内容。如何发挥畜牧业的新功能,实现畜牧业的持续健康发展是当代农业的一个发展方向。文章从畜牧业的功能入手,分析了人们对畜牧业旅游功能认识的瓶颈,并以西安秦岭野生动物园为例,对西安畜牧业旅游功能的开发进行探讨。  相似文献   

5.
The association between the occurrence of a lumbosacral transitional vertebra (LTV) and the cauda equina syndrome (CES) in dogs was investigated. In 4000 control dogs without signs of CES, 3.5% had an LTV, while in 92 dogs with CES, 16.3% had an LTV. The lesion causing CES always occurred between the last true lumbar vertebra and the LTV. Dogs with an LTV were eight times more likely to develop CES than dogs without an LTV. German Shepherd dogs were eight times more likely to develop CES compared with other breeds. Male dogs were twice as likely to develop CES than females. Dogs with an LTV develop CES 1-2 years earlier than dogs without an LTV.  相似文献   

6.
旅游产业是当今世界上发展前景广阔、产业规模庞大的新兴产业。广安市是中国一代伟人——邓小平同志的故居,是红色旅游胜地,还是著名的地质公园——华蓥山所在地.因此,探索广安市旅游产业的发展途径显得尤为重要。文中主要从广安市旅游发展的实际问题出发,分析了广安市旅游产业的地位和现状,用SWOT模型法对广安市旅游产业的优势(Strength)、弱点(Weakness)、机会(Opportunity)和威胁(Threat)进行了综合分析,并在此基础上提出了广安市旅游产业的发展对策。  相似文献   

7.
OBJECTIVE: To compare abomasal luminal gas pressure and volume and perfusion of the abomasum in dairy cows with a left displaced abomasum (LDA) or abomasal volvulus (AV). ANIMALS: 40 lactating dairy cows (25 with an LDA and 15 with an AV). PROCEDURE: Abomasal luminal gas pressure and volume and pulse oximetry values for the caudal portion of the dorsal ruminal sac and abomasal wall were measured during laparotomy. Abomasal perfusion was assessed on the basis of abomasal O2 saturation (pulse oximetry) before correction of the LDA or AV. Abomasal perfusion was also assessed after correction of the LDA or AV by measuring venous O2 saturation in the right gastroepiploic vein and calculating the abomasal oxygen-extraction ratio. RESULTS: Abomasal luminal gas pressure and volume were higher in cattle with an AV than in cattle with an LDA. Abomasal O2 saturation was lower and abomasal oxygen-extraction ratio higher in cattle with an AV, compared with values in cattle with an LDA. In cows with an AV, lactate concentration in the gastroepiploic vein was greater than that in a jugular vein, whereas no difference in lactate concentrations was detected in cows with an LDA. Abomasal luminal gas pressure was positively correlated (r, 0.51) with plasma lactate concentration in the gastroepiploic vein and negatively correlated (r, -0.32) with abomasal O2 saturation determined by use of pulse oximetry. CONCLUSIONS AND CLINICAL RELEVANCE: Abomasal perfusion decreases as luminal pressure increases in cattle with an AV or LDA.  相似文献   

8.
Internal abdominal hernias are an uncommon occurrence in the horse. Protrusion of an abdominal organ or viscus may occur through a normal or pathological aperture within the peritoneal cavity, and incarceration of bowel through such an opening may lead to a strangulating obstruction of the intestine, characterised by luminal blockage and concurrent vascular compromise. As such, entrapment of bowel in internal hernias can represent an important indication for colic surgery in the horse.  相似文献   

9.
Provision of an adequate immunoglobulin mass to dairy calves is an essential component for survival, health, and future productivity. To prevent FPT of immunity due to suckling of the dam, newborn dairy calves should be removed from the calving area within 30 minutes of birth. First and later lactation cows are suitable colostrum donors, provided they are healthy, well-vaccinated, have had optimal transition management, and an appropriate dry-period length. Early colostrum collection yields an adequate immunoglobulin mass provided that 3 to 4 L of colostrum is fed to the newborn calf. Regular testing for the adequacy of the dairy's colostrum feeding program is an excellent way to prevent calf health problems and identify potential need for CSs or replacement products.  相似文献   

10.
The presence of an intravaginal sponge impregnated with the fluoro-progestagen is responsible for an alteration in the bacterial flora of cervical mucus of the ewe at the first oestrus following withdrawal. There is an increase in the number of coliform organisms, specifically E. coli, Alcaligenes spp and other Gram negative bacteria, and C. pyogenes, probably through contamination of the string by facees and urine and the actual presence of an intravaginal foreign body.  相似文献   

11.
1997~1999年在四川雅安青农江江滩采集野生扁穗牛鞭草,通过无性系选择选出新品系H2003-5;2003~2006年,在雅安市四川农业大学草学系基地进行品比试验;2006~2008年,在四川雅安、洪雅、南充和重庆荣昌参加区域试验和生产试验;2009年经全国草品种审定委员会审定通过,作为野生栽培驯化品种登记,命名为“雅安”扁穗牛鞭草,新品种产草量高,适应性强,是优良的多年生暖季型牧草,适合在长江中下游地区种植.  相似文献   

12.
OBJECTIVE: To determine risk factors associated with identification of an umbilical hernia during the first 2 months after birth in Holstein heifers. DESIGN: Case-control study. ANIMALS: 322 Holstein heifers born in a single herd (45 with an umbilical hernia and 277 without). PROCEDURE: Risk factors that were examined included sire, whether the dam had a history of umbilical hernia, milk yield, duration of gestation, whether the dam had a history of dystocia, whether the heifer had a twin, birth weight, total serum protein concentration, and whether the heifer had an umbilical infection. Logistic regression was used to analyze risk factors. RESULTS: Heifers born to sires with > or = 3 progeny with an umbilical hernia were 2.31 times as likely to develop an umbilical hernia as were heifers born to sires with < or = 2 progeny with an umbilical hernia. Heifers with umbilical infection were 5.65 times as likely to develop an umbilical hernia as were heifers without umbilical infection. CONCLUSIONS AND CLINICAL RELEVANCE: Sire and umbilical infection were associated with risk of an umbilical hernia during the first 2 months of life in Holstein heifers. Attributable proportion analysis indicated that the frequency of umbilical hernias in Holstein heifers with umbilical infection would have been reduced by 82% if umbilical infection had been prevented.  相似文献   

13.
The structural characteristics of the ventricular myocardium and the arterial distribution of the ventricular wall were studied in two freshwater teleost fish species (Piaractus mesopotamicus and Clarias gariepinus). The ventricular myocardium consists of two distinct layers, an external compact layer and an internal spongy layer. In Piaractus mesopotamicus the compact layer contains fibres with an external longitudinal arrangement and an internal circular arrangement. The arterial vascularization of the compact layer is provided by subepicardial vessels and their ramifications in both species.  相似文献   

14.
A 19-yr-old spayed female coyote (Canis latrans) was evaluated for an elliptical swelling of the skin beneath its right eye and an elevated mass that involved the soft and hard palate and gingivae around the upper right carnassial tooth and molars. Histopathologic analysis revealed a squamous cell carcinoma, and a postmortem examination revealed no evidence of vascular invasion or dissemination to the regional lymph nodes or viscera. This report describes the biology and progresion of an oral squamous cell carcinoma in an aged captive coyote.  相似文献   

15.
Continuous exposure to an aversive mixture was investigated as a means of maintaining aversion to vermeerbos in sheep subjected to the social influence of non-averted sheep. The use of an aversive mixture was based on a hypothesis that continuous exposure to an acceptable aversive mixture (containing both the aversive substance and the identification factors of vermeerbos mixed with maize meal) would tempt sheep to consume small quantities of the aversive mixture each day and that this would keep them averted to vermeerbos, despite the social influence of non-averted sheep. Persistent aversion to a vermeerbos-maize meal mixture (1:99 by mass) by sheep continuously exposed to such an aversive mixture, after an initial aversion conditioning with lithium chloride (LiCl, 160 mg/kg BM), was demonstrated. Aversion in adjacent controls not exposed to the aversive mixture only lasted for some time. A similar result was obtained when sheep were challenged for intake of a pure stand of established vermeerbos. Three sheep continuously exposed to an aversive mixture after an initial aversion conditioning totally refused grazing the vermeerbos during a 42-day trial, despite the social influence of three non-averted control sheep grazing vermeerbos on an adjacent site. These results were confirmed by a second replication the following year. Joint grazing for an hour a day by averted and non-averted sheep during the last seven days of this replication also resulted in total avoidance of vermeerbos by the averted animals, despite continued intake of vermeerbos by the control sheep  相似文献   

16.
1. We investigated whether an individual duckling's (Anas platyrhynchos domesticus) attributes were associated with its response to an approaching human when it was a member of one of three flocks of 12. 2. Each individual was scored according to its response to (i) an approaching human when alone and feeding, (ii) a taxidermist's model fox when alone and feeding, and (iii) an approaching human when alone in a 9 m annulus, and its nearest neighbour distance in the home pen, competitiveness for food in a series of paired encounters, running ability and physical characteristics. 3. Each flock was herded around a 7 m diameter annulus in separate trials by a human walking at 0.5ms(-1). The distance maintained by each duckling from the human, and hence its relative flock position, was calculated. 4. Individual flight distance maintained from an approaching human when alone in an annulus was the attribute that predicted distance maintained from an approaching human when part of a flock. 5. Some ducklings had reduced average distances from an approaching human when they were in a flock compared to when they were tested alone, and inter-individual variation in distance from the human was greatly reduced when birds were part of a flock.  相似文献   

17.
We used a p26 recombinant protein (p26r) from equine infectious-anemia virus (EIAV) expressed in Escherichia coli as antigen to standardize an agar-gel immunodiffusion (AGIDp26r) test and an indirect ELISA (ELISAp26r) for the detection of antibodies against EIAV in 720 equine sera from Brazil. We evaluated the tests's relative diagnostic sensitivities (relSe) and relative diagnostic specificities (relSp) against a commercial AGID kit (Idexx™, USA). We used three sera panels: panel A—196 AGID-negative sera from an AIE non-endemic controlled area; panel B—194 AGID-negative sera from an AIE endemic area and panel C—330 AGID-positive sera from an AIE endemic area. ELISAp26r cut-off value was defined with TG-ROC using sera from panels A and C. AGIDp26r showed an agreement of 100% with the commercial kit. When applied to sera from panels A and C, ELISAp26r showed an agreement of 100% with the kit, but, although relSe was 100% for panel C, the ELISAp26r had relSp of 93.3%.  相似文献   

18.
Measurements of coagulation factor XII levels in F1 progeny of a cat having factor XII deficiency revealed an autosomal recessive pattern similar to that reported in humans (Hageman trait). A study of the pedigree of the colony revealed that F1 kittens had approximately 50% factor XII activity while kittens produced by backcrossing with an F1 progeny possessed an average of 50% and a less than 2% factor XII activity in an approximate 1:1 ratio. Kittens having an average of 50% factor XII activity were postulated heterozygous for the trait while progeny with less than 2% activity were considered genetically homozygous.  相似文献   

19.
Four cases of malignant neoplasia in captive wild birds are described: an adenocarcinoma of the adrenal gland in a Mountain duck (Tadorna tadornoides), a malignant melanoma in the thoracic cavity of a Combed duck (Sarkidiornis melanotos), a hepatocellular carcinoma with pulmonary metastasis in an Asian Purple Swamphen (Porphyrio porphyrio), and an undifferentiated carcinoma in the abdomen with metastasis to skeletal muscle in a White-Breasted Waterhen (Amaurornis phoenicurus). The tumors were diagnosed during a 1-year period and represented an incidence of neoplasia of 3.1%. These appear to be the first documented cases of a malignant adrenal gland tumor and a non-ocular melanoma in the order Anseriformes. The hepatocellular carcinoma failed to react with an immunoperoxidase stain for alphafetoprotein.  相似文献   

20.
Botryomycosis is an uncommon chronic bacterial infection that can have cutaneous and visceral involvement. This report describes an 18-year-old mixed-breed mare presented with dysphagia, dyspnoea and an upper respiratory noise that developed secondary to oropharyngeal botryomycosis. Histological examination of the mass showed a granulomatous formation with Splendore–Hoeppli phenomenon surrounding Gram-positive bacteria. This report describes the clinical signs, approach and management of an oropharyngeal Staphylococcus aureus granuloma in a geriatric mare.  相似文献   

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