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171.
172.
M. C. Vidotto S. F. Kano F. Gregori S. A. Headley O. Vidotto 《Zoonoses and public health》2006,53(9):404-411
Anaplasma marginale is an obligate intraerythrocytic rickettsial pathogen (order, Rickettsiales: family, Anaplasmataceae) that causes bovine anaplasmosis. This disease is widely distributed in tropical and sub‐tropical regions of the world and causes important economic losses to cattle production. Major surface protein (MSP)1a (msp1α gene) is one of the six MSPs identified on A. marginale from cattle, whose sequence and size vary according to the number of tandem 28‐ to 29‐amino acid repeats. This study characterized the msp1α and msp4 genes obtained from three distinct Brazilian herds from the State of Paraná. Three strains of the msp1α and one strain of the msp4 gene were sequenced. The strains evaluated revealed PCR products of different size, representing three, five and six internal repeats. Sequence analyses confirmed the number of tandem sequence copies and revealed a high degree of sequence identity with strains from other Brazilian States, as well as strains from the USA, Europe and Israel. The msp1α DNA and amino acid sequences from A. marginale and DNA sequences of msp4 strains did not reveal distinct phylogeographical segregation. However, the amino acid sequences of msp4 demonstrated definite phylogeographical relationship. These results suggest that the amino acid sequences of msp4 should be used for phylogenetic identification of A. marginale strains and may be an important tool for the epidemiology and control of anaplasmosis. Additionally, the close similarity of the Paraná strains of A. marginale with strains from USA, Europe and Asia may reflect the introduction of these genes during the development of the Brazilian bovine herd. 相似文献
173.
C. Devitt L. Boyle D. L. Teixeira N. E. O’Connell M. Hawe A. Hanlon 《Irish veterinary journal》2015,69(1):17
Background
A SWOT (Strengths, Weaknesses, Opportunities and Threats) analysis is a strategic management tool applied to policy planning and decision-making. This short report presents the results of a SWOT analysis, carried out with n?=?16 stakeholders i) involved in the pig industry in the Republic of Ireland and Northern Ireland, and ii) in general animal welfare and food safety policy areas. As part of a larger study called PIGWELFIND, the analysis sought to explore the potential development of pig meat inspection as an animal welfare and diagnostic tool.Findings
The final SWOT framework comprised two strengths, three opportunities, six weaknesses, and five threats. Issues around relationships and communication between producers and their veterinary practitioner, processors and producers were common to both the strengths and weakness clusters. Practical challenges within the processing plant were also named. Overall, the SWOT framework complements results reported in Devitt et al. (Ir Vet J 69:2, 2016) regarding problematic issues within the current system of information feedback on meat inspection especially within the Republic of Ireland, and the wider challenges of communication and problems of distrust.Conclusion
The results of the SWOT analysis support the conclusions from Devitt et al. (Ir Vet J 69:2, 2016), that trust between all stakeholders across the supply chain will be essential for the development of an effective environment in which to realise the full diagnostic potential of MI data. Further stakeholder engagement could seek to apply the findings of the SWOT analysis to a policy Delphi methodology, as used elsewhere.174.
Use of genomic recursions and algorithm for proven and young animals for single‐step genomic BLUP analyses – a simulation study 下载免费PDF全文
B.O. Fragomeni D.A.L. Lourenco S. Tsuruta Y. Masuda I. Aguilar I. Misztal 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(5):340-345
The purpose of this study was to examine accuracy of genomic selection via single‐step genomic BLUP (ssGBLUP) when the direct inverse of the genomic relationship matrix ( G ) is replaced by an approximation of G ?1 based on recursions for young genotyped animals conditioned on a subset of proven animals, termed algorithm for proven and young animals (APY). With the efficient implementation, this algorithm has a cubic cost with proven animals and linear with young animals. Ten duplicate data sets mimicking a dairy cattle population were simulated. In a first scenario, genomic information for 20k genotyped bulls, divided in 7k proven and 13k young bulls, was generated for each replicate. In a second scenario, 5k genotyped cows with phenotypes were included in the analysis as young animals. Accuracies (average for the 10 replicates) in regular EBV were 0.72 and 0.34 for proven and young animals, respectively. When genomic information was included, they increased to 0.75 and 0.50. No differences between genomic EBV (GEBV) obtained with the regular G ?1 and the approximated G ?1 via the recursive method were observed. In the second scenario, accuracies in GEBV (0.76, 0.51 and 0.59 for proven bulls, young males and young females, respectively) were also higher than those in EBV (0.72, 0.35 and 0.49). Again, no differences between GEBV with regular G ?1 and with recursions were observed. With the recursive algorithm, the number of iterations to achieve convergence was reduced from 227 to 206 in the first scenario and from 232 to 209 in the second scenario. Cows can be treated as young animals in APY without reducing the accuracy. The proposed algorithm can be implemented to reduce computing costs and to overcome current limitations on the number of genotyped animals in the ssGBLUP method. 相似文献
175.
Barry O. Hughes 《British poultry science》1993,34(3):625-626
Poultry Health and Management: Chickens, Ducks, Turkeys, Geese, Quail, 3rd edn. By David Sainsbury, 1992. 214 pp., illustrated. Oxford, Blackwell Scientific Publications. £17.99. ISBN 0–632–03325–8. 相似文献
176.
Indigenous chicken (IC) and their production systems were characterized to understand how the whole system operates for purposes
of identifying threats and opportunities for holistic improvement. A survey involving 594 households was conducted in six
counties with the highest population of IC in Kenya using structured questionnaires. Data on IC farmers’ management practices
were collected and analysed and inbreeding levels calculated based on the effective population size. Indigenous chicken were
ranked highest as a source of livestock income by households in medium- to high-potential agricultural areas, but trailed
goats in arid and semi-arid areas. The production system practised was mainly low-input and small-scale free range, with mean
flock size of 22.40 chickens per household. The mean effective population size was 16.02, translating to high levels of inbreeding
(3.12%). Provision for food and cash income were the main reasons for raising IC, whilst high mortality due to diseases, poor
nutrition, housing and marketing channels were the major constraints faced by farmers. Management strategies targeting improved
healthcare, nutrition and housing require urgent mitigation measures, whilst rural access road network needs to be developed
for ease of market accessibility. Sustainable genetic improvement programmes that account for farmers’ multiple objectives,
market requirements and the production circumstances should be developed for a full realization of IC productivity. 相似文献
177.
Kagawa S Klein F Corboz L Moore JE Murayama O Matsuda M 《Veterinary research communications》2001,25(7):565-575
Forty-six isolates of Taylorella equigenitalis were analysed by pulsed-field gel electrophoresis (PFGE) after separate digestion of the genomic DNA with ApaI and with NotI. The isolates had been obtained from horses in six European countries and were classified into 18 genotypes. In Belgium, 2 genotypes were detected in 2 isolates, in England 9 among 15, in Finland 2 in 2, in France 2 among 10, in Sweden 3 among 5, and in Switzerland 3 among 12. Two English isolates and 4 French isolates gave identical PFGE profiles to those of Kentucky 188 from the United States. A common genotype was found in 5 isolates from Belgium and England and also in 10 isolates from France and Switzerland. The analysis of genomic DNA from 12 isolates of T. equigenitalis obtained from male horses in France, Sweden and Switzerland gave no evidence of a sex-related difference in the genomic DNA. Genomic DNA from 11 streptomycin (STM)-susceptible isolates obtained in Sweden and Switzerland were classified into four genotypes by PFGE. Each of the six genotypes determined among the 17 isolates from these two countries had single phenotypes for resistance or susceptibility to STM. 相似文献
178.
Syakalima O Choongo K Nakazato Y Onuma M Sugimoto C Tsubota T Fukushi H Yoshida M Itagaki T Yasuda J 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(3):315-318
Exposure and ecological risks to heavy metals (copper, zinc, manganese, iron) at Lochnivar and Blue Lagoon National Parks in wildlife dependent on the Kafue river contaminated with mining waste was evaluated. Samples included water, fish, grasses and Kafue Lechwe (Kobus leche kafuensis) liver. At both parks copper ranged from 0.03-0.04 mg/l; 3.0-6.0 mg/kg; 11.0-44.0 mg/kg; trace -199.0 mg/kg; while zinc was 0.01 mg/l; 32.0-82.0 mg/kg; 15.0-21.0 mg/kg; and 52.0-138.0 mg/kg; in water, fish, grasses and lechwe, respectively. Manganese ranges were 0.15-0.16 mg/l; 7.0-18.0 mg/kg; 51.0-145.0 mg/kg; and 40.0-53.0 mg/kg while iron ranges were 0.13-0.14 mg/l; 26.0-134.0 mg/kg; 1766.0-1797.0 mg/kg; and 131.0-856.0 mg/kg; in water, fish, grasses and lechwe, respectively. Levels in all samples except water were high indicating potential for adverse effects. 相似文献
179.
The safety and protective efficacy of a horse antiserum raised against inactivated whole cell preparations of Streptococcus suis serotype 2 was investigated in pigs by experimental challenge. The antiserum was evaluated in two similar experiments each comprising 12 4-week-old pigs treated with 6 ml of antiserum the day before challenge and four pigs used as challenge controls. Pigs were infected by subcutaneous injection with approximately 10(11) colony forming units of S. suis serotype 2. Clinical disease in the pigs that could be attributed to infection with S. suis was reduced from 88 to 35% (P = 0.015). The percentage of pigs with lesions that could be associated with S. suis was reduced from 88 to 22% (P = 0.002) and isolation of S. suis serotype 2 was reduced from five (63%) out of eight pigs in the combined challenge control groups to 3 (13%) out of 23 pigs in the combined treatment groups. These results indicate that passive immunization of pigs may be a way to reduce or control S. suis serotype 2 infections in pigs. 相似文献
180.