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61.
J. Cabaret H. M. Baudet J. Devos J. Hubert J. Cortet C. Sauv 《Veterinary parasitology》1995,60(3-4):331-337
Multispecific resistance to benzimidazoles was studied in three selected farms. These farms had bred dairy goats for more than 15 years. The helminths were introduced with the goats at the establishment of the farms which afterwards remained isolated. Nematode resistance could then be related to their own management practices. Faecal egg count tests and egg hatch assays were performed to assess intensity of resistance. The generic (infective larvae in faecal cultures) and specific richness (adult worms) were assessed. The resistant species were Trichostrongylus colubriformis, Teladorsagia circumcincta, Haemonchus contortus and Oesophagostomum venulosum. Faecal egg count reduction tests and egg-hatch assays did not match exactly. Faecal larval counts after treatments gave a distorted picture of multispecific resistance: Haemonchus and Oesophagostomum were very largely over represented. The number of species found in the three farms was relatively low compared with other reports in goat farms of the area. This reduction of diversity might also be due in part to characteristics of breeding management and history (use of permanent pasture and introduction of goats at the establishment of farm). 相似文献
62.
不同放牧强度对滩羊生产性能影响的研究 总被引:4,自引:2,他引:2
为寻找适宜宁夏盐池县草地的放牧强度,于2003年5-11月在该县四墩子试点设5个处理(0.45、0.60、1.75、1.05和1.50只/hm2)进行轮牧,轮牧周期为42 d,共放牧154 d。结果表明:1)滩羊采食量随放牧强度的加重而降低。同一放牧强度下,随放牧时间推移,采食量先逐渐增大而后下降。2)在试验期内,不同放牧强度下,滩羊体重随时间推移总体上都呈增加趋势。在10月2日之后体重开始出现分化。与放牧强度重的处理相比,放牧强度轻的处理日增重峰值较高,持续时间较长。3)滩羊个体增重与放牧强度之间存在着强的负相关;单位草地面积(1 hm2)增重与放牧强度之间呈强的正相关,初步可以确定在该类草地上放牧强度应在0.75只/hm2左右。4)随着放牧强度的加重,饲料报酬先增大后减小。在同一放牧强度下,饲料报酬随时间的推移先升高后降低。5)当放牧强度超过0.75只/hm2以后,滩羊出现了空怀、产羔率降低和推迟怀孕的现象。6)综合考虑各研究指标,该类草地放牧强度以不应超过0.75只/hm2为宜。 相似文献
63.
64.
Verification by polymerase chain reaction of vertical transmission of Theileria sergenti in cows 总被引:2,自引:0,他引:2
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Byeong K. Baek Kim B. Soo Jin H. Kim Jin Hur Bou O. Lee J. M. Jung Misao Onuma Anthony O. Oluoch Chang-Hyun Kim Ibulaimu Kakoma 《Canadian journal of veterinary research》2003,67(4):278-282
To evaluate the transplacental transfer of Theileria sergenti infection in cattle, we used DNA probes to detect T. sergenti in 6 pregnant cows and their calves. All the animals were monitored by parasitologic, serologic, and polymerase chain reaction (PCR) assays for a predicted 875-base-pair (bp) DNA product and a 684-bp amplicon detected by nested PCR in the blood and spleens of aborted fetuses. An open reading frame (ORF) starting at nucleotide 170 and terminating at position 1021 was shown to code for a polypeptide of 283 amino acid residues. All 6 dams and 5 calves were positive for T. sergenti in all tests. One calf was positive only with nested PCR. We conclude that transplacental transmission of T. sergenti is a significant problem. The relevance of the data in the programmed introduction of new (especially pregnant) animals into established clean herds needs serious consideration with regard to control of theileriosis and other tickborne diseases. 相似文献
65.
M E Olson C J Hannigan P F Gaviller L A Fulton 《The Canadian veterinary journal. La revue veterinaire canadienne》2001,42(11):865-868
Dogs (n = 13), which had failed to be cured of giardiosis following chemotherapeutic measures, were treated with a Giardia vaccine (2-3 injections). Clinical signs resolved between 16 and 42 days postvaccination and cessation of fecal cyst shedding was between 21 and 70 days. Vaccination is a potential method of treating giardiosis in dogs. 相似文献
66.
Χ灾绷吹矸酆康挠跋焓钦?,直接影响比间接影响大。Study on the correlation between rice quality and agronomic traits of quality riceNIE Cheng rong, WEN Yu hui, WANG Yun bo, CHEN Ming zhong,LI Mei, LIU Dao quan(Agronomy Department, Foshan University , Nanhai 528231,China)The correlative analy 相似文献
67.
DONOSO Leonito Acosta 《中国林业科技(英文版)》2005,(1)
The Luntiang Kamaynilaan Project (Metro ManilaGreening Project) launched in 1988 planted trees inmajor thoroughfares, center islands, school premisesand other idle public lands, was basically a governmenteffort. When the funds ran out, the project also fizzledout. In both projects however, it is evident that the keyfactor is peoples participation.Gaining lessons from the past two projects, thegovernment established a collaborative effort ofgovernment and non-government organizations. TheCl… 相似文献
68.
69.
E M Aburto A Cribb I C Fuentealba B O Ikede F S Kibenge F Markham 《Canadian journal of veterinary research》2001,65(2):104-110
This study evaluates the ability of selenium (Se) supplementation to prevent experimental copper (Cu)-induced hepatocellular damage. Weanling male Fischer 344 rats were randomly assigned to groups of 15, 3 groups (A,B,C) were fed Cu-loaded diets (containing 2000 microg/g copper, added as CuSO4) and different levels of Se (added as Na2SeO3 x 5H2O) as follows: A) Cu-loaded/Se adequate diet (0.4 microg/g Se, fed basis); B) Cu-loaded/Se-supplemented diet (2 microg/g Se); and C) Cu-loaded/Se-deficient diet (< 0.2 microg/g). Three additional groups (D,E,F) were fed diets containing adequate levels of Cu (14 microg/g Cu, fed basis) and different levels of Se as follows: D) Cu-adequate/Se-adequate diet; E) Cu-adequate/Se-supplemented diet (2 microg/g Se); and F) Cu-adequate/Se-deficient (< 0.2 microg/g) diet. After 4, 8, and 12 weeks on the experimental diets, liver samples were processed for histology, histochemistry, metal analysis, glutathione peroxidase (GSH-Px) measurement, and quantification of malondialdehyde (MDA). Morphologic changes characteristic of Cu-associated hepatitis, without an increase in hepatic MDA levels, were seen in all Cu-loaded rats in each sampling. Similar changes occurred in rats fed Se-adequate, Se-supplemented and Se-deficient diets. This study demonstrates that Fischer 344 rats fed 2000 microg/g Cu develop morphologic changes due to Cu toxicity without evidence of lipid peroxidation. Furthermore, Se supplementation does not result in protection against Cu-induced liver injury. 相似文献
70.
This paper depicted the physiographic landscape features and natural vegetation situation of study area (the eastern Jilin
Province), and expatiates the definition, basic characters and its development of Ecological Land Classification (ELC). Based
on the combination of relief map, satellite photography for study area and vegetation inventory data of 480 sample sites,
a 5-class and a 15-class ecological land type map was concluded according to 4 important factors including slope, aspect,
vegetation and elevation. Ecological Classification System (ECS) is a method to identify, characterize, and map ecosystems.
The Ecological Land Type (ELT) was examined and applied initially in eastern Jilin Province.
Foundation item: This paper was supported by Chinese Academy of Sciences “100 people” project and the Open Research Station of Changbai Mountain
Forest Ecosystem.
Biography: XIAO Bao-ying (1974-), female, postgraduate in Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016,
P. R. China
Responsible editor: Zhu Hong 相似文献