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1.
The objective of this study was to compare the application of different in vitro and in situ methods in empirical and mechanistic predictions of in vivo OM digestibility (OMD) and their associations to near-infrared reflectance spectroscopy spectra for a variety of forages. Apparent in vivo OMD of silages made from alfalfa (n = 2), corn (n = 9), corn stover (n = 2), grass (n = 11), whole crops of wheat and barley (n = 8) and red clover (n = 7), and fresh alfalfa (n = 1), grass hays (n = 5), and wheat straws (n = 5) had previously been determined in sheep. Concentrations of indigestible NDF (iNDF) in all forage samples were determined by a 288-h ruminal in situ incubation. Gas production of isolated forage NDF was measured by in vitro incubations for 72 h. In vitro pepsin-cellulase OM solubility (OMS) of the forages was determined by a 2-step gravimetric digestion method. Samples were also subjected to a 2-step determination of in vitro OMD based on buffered rumen fluid and pepsin. Further, rumen fluid digestible OM was determined from a single 96-h incubation at 38°C. Digestibility of OM from the in situ and the in vitro incubations was calculated according to published empirical equations, which were either forage specific or general (1 equation for all forages) within method. Indigestible NDF was also used in a mechanistic model to predict OMD. Predictions of OMD were evaluated by residual analysis using the GLM procedure in SAS. In vitro OMS in a general prediction equation of OMD did not display a significant forage-type effect on the residuals (observed - predicted OMD; P = 0.10). Predictions of OMD within forage types were consistent between iNDF and the 2-step in vitro method based on rumen fluid. Root mean square error of OMD was least (0.032) when the prediction was based on a general forage equation of OMS. However, regenerating a simple regression for iNDF by omitting alfalfa and wheat straw reduced the root mean square error of OMD to 0.025. Indigestible NDF in a general forage equation predicted OMD without any bias (P ≥ 0.16), and root mean square error of prediction was smallest among all methods when alfalfa and wheat straw samples were excluded. Our study suggests that compared with the in vitro laboratory methods, iNDF used in forage-specific equations will improve overall predictions of forage in vivo OMD. The in vitro and in situ methods performed equally well in calibrations of iNDF or OMD by near-infrared reflectance spectroscopy.  相似文献   

2.
Information gathered from cases of fowl cholera (FC) in commercial turkey flocks through case records, flock records, and telephone and mail surveys was used to estimate disease costs. The cost to the Georgia commercial turkey industry in 1986 from preventive measures, treatment of outbreaks, and production losses from the disease was estimated at $634,545. The cost of FC per kg of live production was estimated to be $0.015.  相似文献   

3.
In 2007, 678 pigs of all age groups out of 347 different farms from Lower Saxony and Northrhine-Westphalia and 86 persons occupationally exposed to pigs were investigated for their nasal colonisation with methicillin-resistant Staphylococcus areus (MRSA) by the Field Station for Epidemiology of the University of Veterinary Medicine Hannover and the Robert Koch-Institute. At the individual animal level, a frequency of positive results of 13% (n = 85 positive animals) and at the herd level, a frequency of positive results of 18% (n = 62 positive herds) were found. All isolates were assigned to the Multilocus Sequence Typing Type ST398. Within MRSA-positive herds, there were more MRSA-negative than MRSA-positive animals. Among the occupationally exposed persons (veterinarians, laboratory personnel and meat inspection personnel), 20 persons (23%) showed a nasal colonisation with MRSA ST398. A quite strong association between the intensity of the contact to pigs with the frequency of nasal colonisation in the occupationally exposed persons was detected. None of the animals or the humans nasally colonised by MRSA ST398 showed any clinical symptoms of a staphylococcal infection. Conclusions are drawn on the herd and intra-herd prevalence of the nasal colonisation of pigs with MRSA ST398 in pigs, but especially on which questions need to be addressed by further research.  相似文献   

4.
中国野生动物驯养与繁殖法律制度的缺陷与完善   总被引:1,自引:0,他引:1  
陈春艳 《野生动物》2006,27(1):53-56
野生动物驯养繁殖在世界野生动物资源保护中具有重要作用,有关野生动物驯养繁殖的法律制度也成为各国野生动物资源保护立法的主要内容。本文针对目前中国野生动物驯养繁殖的立法现状与存在问题,提出完善中国野生动物驯养繁殖的国内法对策,以推进中国野生动物资源保护立法的发展。  相似文献   

5.
In 5 cases of glaucoma (2 from trauma, 2 from narrowed drainage angles, 1 secondary to lens extraction), cyclocryotherapy was used to control intraocular pressure. In all cases the intraocular pressure decreased, with the usual result being a cosmetic and painless but blind eye.  相似文献   

6.
中国圈养野生动物疫苗使用调查   总被引:1,自引:0,他引:1  
2005年对中国动物园协会单位中的18家动物园饲养野生动物疫苗免疫情况进行调查。受调查动物园在野生动物疫苗使用和动物种类方面具有一定的代表性。调查结果显示动物园动物现共使用18类36种疫苗,预防31种疫病。其中哺乳动物使用14类24种疫苗,预防24种疫病;禽类使用4类12种疫苗,预防7种疫病。使用范围最广的有禽流感、犬瘟热疫苗等、新城疫疫苗、猫瘟热疫苗等。共有24目58科动物接种疫苗,其中食肉动物类1目8科,食草动物类3目9科,杂食动物类2目3科,禽类18目38科。研究结果提示应加强动物园之间疫病信息交流、防疫资源的利用、疫病监测和研究,加大对动物园动物疫病的研究投入,逐步建立动物园动物统一的防疫规程。  相似文献   

7.
应激宁对HSP70在大鼠应激性溃疡中表达的影响   总被引:2,自引:0,他引:2  
为了探讨热休克蛋白70(HSP70)在应激性溃疡中表达的变化及应激宁对其变化的影响,选用Wistar大鼠水浸-束缚应激(WRS)4 h的方法,建立应激性溃疡模型.用免疫组织化学方法检测胃黏膜组织HSP70的表达.结果表明,HSP70的表达主要分布在胃腺区,对照组大鼠胃黏膜组织中有散在的表达,应激组中HSP70阳性细胞数目较应激宁组增多,两者具有明显的差异(P<0.05),而且,应激组和应激宁组中HSP70阳性细胞数目均比对照组明显增多(P<0.01).表明应激宁对WRS后胃黏膜组织HSP70的表达具有调节作用,这也表明应激宁具有抗应激的作用.  相似文献   

8.
A study was conducted to determine the seroprevalence of leptospirosis and infecting serovars across livestock (cattle, sheep, goats, and pigs) in Trinidad using the microscopic agglutination test with an international panel of 23 serovars. Of a total of 590 cattle tested, 21.5% were seropositive with agglutinations to 13 of the 23 antigens used in the panel. Icterohaemorrhagiae (9.3%), Sejroe (4.1%), Ballum (4.1%), and Autumnalis (1.9%) were the predominant serogroups detected in the cattle sampled (n = 590). Of 222 sheep tested, 5.0% were seropositive with agglutinations to five serovars belonging to two serogroups. These serogroups were Autumnalis at 2.7%, and Icterohaemorrhagiae at 2.3% of all sheep tested (n = 222). Of a total of 180 goats tested, 3.3% were seropositive, all agglutinating to the Icterohaemorrhagiae serogroup, 1.7% to serovar Copenhageni, 1.1% to serovar Mankarso, and 0.6% to serovar Icterohaemorrhagiae. Among pigs (n = 200), 5.0% were seropositive for five serovars belonging to three serogroups. These serogroups were Icterohaemorrhagiae at 2.5%, Australis at 2%, and Ballum at 0.5%. Overall, age and sex of animals were not significantly associated with leptospirosis with the exception of cattle where age was a significant factor for seropositivity. It was concluded that for livestock, leptospirosis may be an important zoonotic and economic disease, particularly in the case of cattle. It is imperative that the impact of leptospirosis on abortion, stillbirths, and decreased milk production in livestock in the country be assessed.  相似文献   

9.
细胞因子是一类小分子多肽,通过自分泌和旁分泌传递细胞应答.细胞因子间复杂的相互作用控制着为保护机体免受病原体侵害而发生的炎症反应和特异性免疫应答,它是启动和维持机体防御功能的调节器,最终决定传递性应答反应类型和作用机制,作为效应分子暂时的、局部的来控制反应的发生范围和持续时间.文章介绍了细胞因子在禽传染病防治中的应用.  相似文献   

10.
The faeces of 205 domestic cattle (Bos taurus) from 5 regions of Saudi Arabia were examined for the presence of coccidian parasites. The following species of Eimeria were recovered: Eimeria auburnensis, E. bovis, E. cylindrica, E. ellipsoidalis, E. subspherica, E. wyomingensis and E. zuerni. A total of 34.1% of the individual faecal samples were positive for the presence of coccidial oocysts. Mixed infections of 2-4 species were found in 15.7% of the specimens. E. zuerni and E. bovis occurred most frequently and were generally the most predominant species. The incidence of coccidia-infected cattle was higher in the eastern region.  相似文献   

11.
A cross-sectional survey of the seroprevalence of brucellosis in sheep, goats and cattle in Kosovo was made in January 2001. A total of 12,000 serum samples, from 7941 cattle, 3548 sheep and 511 goats, were screened using the Rose Bengal test. Doubtful and positive results were further tested with competitive and indirect ELISAS. The overall serological prevalences derived from the samples positive to all three tests, were 6.26 per cent (95 per cent confidence intervals [CI] 5.5 to 7.1 per cent) for sheep, 7.24 per cent (5.3 to 9.8 per cent) for goats and 0.58 per cent (0.43 to 0.77 per cent) for cattle. The survey covered 26 of the 29 municipalities and showed that brucellosis was widely but unevenly distributed throughout the province. Seropositive animals were found in 25 per cent (19 to 32 per cent) of 162 villages surveyed. The risk of cattle being infected on holdings where both cattle and sheep were kept was greater, with a risk ratio of 4.6 (2.2 to 9.6), than on holdings where only cattle were kept. Brucella melitensis probably predominates as the cause of brucellosis in ruminants in the province of Kosovo.  相似文献   

12.
精原干细胞体外培养研究进展   总被引:2,自引:1,他引:1  
精原干细胞(SSCs)是指位于睾丸生精小管基膜上既能自我更新维持自身群体数量恒定,又能定向分化形成精母细胞,最终形成精子的一类原始干细胞。其体外培养以及近年来兴起的移植、基因转染的深入研究,为探讨精子的发生机制、重建不育个体的精子发生、生产转基因动物提供了新的途径。文章综述了精原干细胞体外培养的研究现状,并对其体外的纯化、鉴定,以及未来的应用进行了介绍,旨在为精原干细胞的研究提供借鉴。  相似文献   

13.
利用PACS(preferential amplification of cod ing sequence)法鉴别鸡中的差异表达基因。结果表明,该方法具有操作简单、假阳性率低、能选择性扩增mRNA编码区等优点,可作为禽类基因差异表达研究中的首选方法。  相似文献   

14.
Outbreaks of dermatophilosis in nine herds of dairy cattle in Israel were studied retrospectively. The outbreaks might have been associated with the exposure of the animals to intense showering during the spring and summer months of May to October, in addition to calving and postcalving stress. The acute exudative form of dermatophilosis occurred in the first-calving cows during the six weeks after they calved. The morbidity rate ranged from 10.0 to 66.6 per cent and the period of morbidity ranged from eight to 19 days. Mortality or culling occurred in four of the herds and ranged from 1.6 to 17.1 per cent. The disease also resulted in a gradual loss of condition, a decrease in milk production and marked increases in the somatic cell counts in milk.  相似文献   

15.
对湖南省2个规模化山羊养殖场进行附红细胞体病的感染调查,结果表明:山羊附红细胞体总感染率为51.4%,其中A场感染率为53.4%,B场感染率为0。将镜检阳性山羊血液人工感染小白鼠,10d后小白鼠体内出现附红细胞体。  相似文献   

16.
Summary Parvaquone was tested in cattle infected withTheileria annulata when they were presented at clinics in the vicinity of Baghdad. Out of over 200 cases presented with suspected theileriosis between July 1984 and July 1985, the drug was used in 45 cases where theileriosis was confirmed by microscopic examination of blood and lymph node biopsy smears. Twenty seven of the cases were considered mild and 18 cases severe. Weights of the cattle were estimated and parvaquone was administered by intramuscular injection at a nominal dose of 20 mg/kg. A single treatment with parvaquone was used in 25 cases and 20 cases were treated twice but there was no correlation between severity of disease and the number of treatments given. Twelve cases (27%) also received antibacterial therapy. All cases were in exotic cattle or cattle born from exotic (imported) cattle and 64% of the cases were in cattle under six months of age. Temperatures dropped immediately after treatment and the majority were normal (below 39.5°C) by two to three days after the first treatment. Of the 45 cases treated 43 recovered. This compares very favourably with a previously reported mortality of 66% in untreated imported cattle in Iraq.
Eficacia Del Parvaquone En El Tratamiento De La Theilerosis Natural En Ganado En Iraq
Resumen Se trató ganado infectado conTheileria annulata en forma natural con parvaquone, en clínicas veterinarias localizadas en la vecindad de Baghdad. De 200 casos admitidos con sospecha de theileriosis, entre julio 1984 y julio 1985, la droga se usó en 45 casos confirmados mediante el examen microscópico de frotis de sangre y biopsias de ganglios linfáticos. Veintisiete de los casos se consideraron moderados y 18 casos severos. Se estimaron los pesos de los animales enfermos, suministrandoles parvaquone vía intramuscular en dosis nominales de 20 mg/kg (rango 16–35 mg/kg). Se utilizó un solo tratamiento con parvaquone en 25 casos clínicos, mediante la aplicación de una sola inyección y se aplicaron dos inyecciones en 20 casos (doble tratamiento), sin que se encontrara correlación alguna entre la severidad de la enfermedad, recuperación y número de tratamientos. Doce casos (27%) recibieron también algún tratamiento antibacteriano. Todos los casos de theileriosis se presentaron en ganado exótico o nacido de ganado exótico (importado) y 64% de los casos ocurrieron en ganado bajo los seis meses de edad. La temperatura bajó inmediatamente después del tratamiento, normalizándose dos o tres días después de tratamiento (bajo 39.5°C). De los 45 casos tratados 43 se recuperaron. Se informa una mortalidad previa de 60% en ganado importado no tratado contra theileriosis en Iraq.

Efficacite De La Parvaquone Pour Le Traitement De La Theileriose Naturelle Des Bovins En Irak
Résumé La parvaquone a été essayée pour le traitement de bovins infectés parTheileria annulata lorsqu'ils étaient présentés aux cliniques des environs de Bagdad. Sur plus de 200 cas présentés pour suspicion de theilériose entre juillet 1984 et juillet 1985, le médicament a été utilisé dans 45 cas où la theilériose était confirmée par l'examen microscopique du sang et de biopsies de ganglions lymphatiques, 27 cas étaient considérés comme des atteintes modérées et 18 comme des cas graves. Les poids des animaux étaient estimés à l'oeil et la parvaquone administrée par voie intra-musculaire à la dose normale de 20 mg/kg (soit 16 à 35 mg/kg). Un traitement unique à la parvaquone a été pratiqué dans 25 cas et il a du être renouvelé dans 20 cas mais il n'y avait pas corrélation entre la gravité des symptômes et le nombre de traitements requis. Dans 12 cas (27%) une thérapie antibactérienne a également été mise en oeuvre. Tous les malades étaient des animaux importés ou issus d'animaux importés et dans 64% des cas les animaux étaient âgés de moins de 6 mois. Les températures ont chuté immédiatement après le traitement et, pour la plupart, étaient normales (moins de 39°5) deux à trois jours après le traitement—sur 45 animaux traités, 43 ont guéri. Ces résultats apparaissent très favorables par rapport à la mortalité de 66% rapportée antérieurement et affectant les bovins non traités en Irak.
  相似文献   

17.
The study was conducted on six reindeers in December. It was established that concentration of reducing sugars in the chyme of jejunum increases substantially (6 times in comparison with abomasum), whereas concentration cellulose, on the contrary, decreases (4.5 times). The maximal increase of monosaccharides in the small intestine testifies to formation of metabolic fund of sugars in this part of the alimentary tract due to high degree of polysaccharides hydrolysis of exogenous, as well as endogenous, microbial formation. Obtained data assume that the need of the reindeer for glucose is provided for not only by gluconeogenesis as it was considered before, but also by absorption of monosaccharides from the alimentary tract.  相似文献   

18.
Polymerase chain reaction (PCR) and deoxyribonucleic acid (DNA) probes were used to characterise trypanosomes from cattle in Morogoro region of Tanzania. Blood samples collected from 390 beef and dairy cattle in selected farms in Morogoro region were examined for presence of trypanosomes using the buffy coat technique (BCT) and blood smears (BSs). Fifty-two animals were found infected: 40 with Trypanosoma congolense, 10 with T. vivax and two with both T. congolense and T. vivax. DNA extracted from all the parasitologically positive and 62 randomly selected parasitologically negative samples were subjected to PCR amplification using primers specific for different trypanosome species. Using a set of seven specific-pairs of primers on the parasitologically positive samples, we detected only T. congolense, either the Savannah- or the Kilifi-type, as single or mixed infections. With the PCR, trypanosome DNA could be detected in 27 (43%) out of 62 samples that were parasitologically negative. DNA hybridisation using probes specific for Savannah- or Kilifi-types T. congolense, or T. vivax, confirmed the presence of these parasites in cattle kept on some farms in Morogoro region of Tanzania. From these studies, it is clear that there is a need to undertake molecular epidemiological studies to determine the distribution of trypanosome species and subspecies, and to assess the economic impact of these parasites in the productivity of livestock in Tanzania. In particular, it would be desirable to verify the assumed association between the different presentations of trypanosomosis on one hand and genotypes of T. congolense on the other.  相似文献   

19.
2014年12月—2015年2月中旬,内蒙古赤峰市的气温偏高、降水偏少,且降水分布不均匀,该气候条件对牧区正常的牧业生产活动产生了不利影响。通过对天然草场牧草返青期与前期气候条件综合分析后,对该地区天然草场牧草返青期进行了预测,即2015年赤峰市天然草场牧草返青期出现在4月下旬—5月上旬,总体较常年偏早3~6 d。  相似文献   

20.
Acute laminitis can be induced experimentally in horses by the administration of carbohydrate, resulting in fermentation within the cecum and ischemia-reperfusion of the digits. The products of fermentation that trigger acute laminitis are as yet unknown; however, compounds such as amines might play a role due to their potential vasoactive properties. The objectives of this study were to quantify the amines present in equine cecal contents and to use a model of carbohydrate overload in vitro to test the hypothesis that carbohydrate fermentation is associated with increased amine production. Cecal contents from each horse were divided into aliquots and incubated anaerobically with either cornstarch or inulin (a form of fructan carbohydrate; both 1 g/100 mL). The pH was measured and samples were taken at the same time for amine measurement by HPLC at 2-h intervals over a 24-h period. In a second set of experiments, the effects of the antibiotic virginiamycin (1 mg/100 mL), calcium (CaPO4; 0.3 g/100 mL), and plant steroidal saponin (Yucca schidigera extract; 0.1 g/100 mL) were examined on pH and amine concentrations in cecal contents incubated with starch or inulin. Both starch and inulin caused significant time-dependent falls in pH, from 6.7 +/- 0.1 at 0 h to 5.2 +/- 0.1 (starch) and 5.0 +/- 0.1 (inulin) at 24 h. Fermentation of carbohydrate was also associated with increased production of phenylethylamine and isoamylamine (two- to threefold increases) as well as putrescine and cadaverine (1.5- to twofold increases). Virginiamycin inhibited the fall in pH and increases in production of phenylethylamine and isoamylamine, while calcium phosphate moderated the changes in pH only. Yucca schidigera extract was without effect. These data show that fermentation of carbohydrate by equine cecal microbiota may lead to increased production of amines.  相似文献   

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