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71.
72.
中国广东家蚕微粒子孢子在Antheraea eucalypti细胞系的感染增殖 总被引:5,自引:0,他引:5
将中国广东的Nosema bombycis CGS,用02mol/LKOH 处理后,接种感染A.eucalypti 细胞系。孢子的发芽率达87% ,在A.eucalypti 细胞初期感染率为27 % 。发育各阶段具2 核,可观察到短极丝孢子和二次感染体形成,孢子芽母细胞按二分裂形成2 个双核的孢子芽,具典型 Nosema 属特征。Nosemabombycis CGS 生物学特性、血清学类型与日本Nosema bombycis NIS001 大致相同,但孢子大小、裂殖体的形态、在A.eucalypti 细胞寄生的细胞感染率、每个细胞的产孢数,2 种微孢子虫却有差异。 相似文献
73.
Michael H. Woodford 《Tropical animal health and production》2009,41(7):1023-1033
Proliferation of disease pathogens capable of affecting humans, domestic livestock and wildlife increasingly threatens environmental
security and biodiversity. Livestock and wild animals in proximity to human beings are often in the chain of transmission
and infection. Globalization of industrial livestock production (especially poultry upon which so much of the burgeoning human
population depends) often permits transcontinental disease spread. Rapidly expanding (and often illegal) international trade
in wild and domestic animals and their products are increasingly involved in the emergence of new diseases that may have the
ability to transmit among humans, livestock and wildlife. Rapidly increasing urbanization has led in many places to overcrowded
townships that rely on “bushmeat” for sustenance and has contributed to the emergence of virulent zoonotic pathogens. The
emergence and proliferation of pathogens are exacerbated by anthropogenic transformation of natural landscapes in order to
increase agricultural and livestock production. This paper posits that data gathered by veterinary ecologists should be interpreted
and used by other disciplines. The importance of a thorough knowledge of the “natural history” (ecology) of the disease agent
and its human, domestic and wild hosts is stressed. 相似文献
74.
Akiyoshi H Sugii S Nahid MA Sone K Tanaka T Zheng C Yijyun L Aoki M Takenaka S Shimada T Shimizu J Kiyomiya K Ohashi F 《Veterinary immunology and immunopathology》2011,144(3-4):255-258
The reactivity of different lectins with crude chromogranin A (CgA) obtained from different animals, namely, cow, horse, dog, pig, and dolphin, was examined to identify lectin(s) that would be useful as coating reagent(s) in a sandwich enzyme-linked immunosorbent assay (ELISA). Of the different lectins studied, the Amaranthus caudatus lectin (ACA), which is specific for the Thomsen-Friedenreich (T)-antigen (Galβ1-3GalNAc), was found to react with the CgA from different animals by western blotting. Purified rabbit anti-bovine CgA antibody was also found to cross-react with the crude CgA preparations. On the basis of these findings, a sandwich ELISA was developed with ACA as the coating reagent and anti-bovine CgA antibody as the probing antibody. Using this method, concentration-dependent curves ranging from 0.003 μg/mL to 25 μg/mL and from 0.02 μg/mL to 25 μg/mL were obtained for bovine CgA and canine CgA, respectively. Similarly, concentration-dependent curves were obtained for the equine, swine, and dolphin crude CgA extracts. Thus, ACA is concluded to be a valuable reagent for CgA detection in crude extracts from different animal species, and for CgA isolation/purification. 相似文献
75.
Research in control of tick-borne diseases and trypanosomosis, and their vectors, namely, ticks and tsetse flies respectively,
has been on going for decades. However, very little attention has been paid to the socio-economic factors that are likely
to influence the outcome of the interventions in the control of these diseases. Thus, this study was designed to investigate
these factors, mainly the intra-household factors influencing decision-making in the control of Vector-borne diseases in the
pastoralist areas of Uganda. These factors included: indigenous technical knowledge, household economic factors, and gender.
Both qualitative and quantitative methods were used in the collection and analysis of data. The tools used for data collection
included among others, participatory learning and action (PLA), and Case studies. The findings included the following: In
pastoralist households, a big proportion of the household budget was allocated to vector-borne diseases control. In the male-headed
households, men dominated decision-making on vector-borne diseases control, although the goals and priorities of men and women
in these households were not the same. Also, vector-borne disease control was predominantly by use of modern veterinary drugs,
and pastoralists treated sick cattle by themselves even in situations where there were veterinary personnel. 相似文献
76.
Ba A Lesnoff M Poccard-Chapuis R Moulin CH 《Tropical animal health and production》2011,43(6):1101-1109
The herds of 95 families were monitored for 1 year in eight villages in the cotton-growing region of southern Mali. In 2006–2007,
reproduction performances were average, with 0.54 calvings/year per cow, and mortality was low. Herd numerical productivity
is not very high, less than 0.13/year, because of the high proportion of males kept for animal draught. Depending on the herd
size, the behaviour of the families differs, in terms of off-take and in-take of animals. Families that only have one or two
draught animals seek to increase their animal draught capacity, with a negative net off-take (−0.13/year). Families with two
to three cows have a very low net off-take (0.02/year), with culling of adult animals compensated by purchase. They therefore
capitalised this year, with an annual herd growth of 8%. Families with a very large herd (20 to 50 cows) take off more of
their stock, with a net off-take of 0.08/year (very few animal purchases) and make a stock growth of 5%. And finally, families
with an average-sized herd (6 to 19 cows) take off the whole of the year’s production, with a net off-take of 0.11/year and
a nil stock growth rate. The use of a demographic model made it possible to measure the sensitivity of the productivity rate
to the different demographic parameters. 相似文献
77.
78.
Abiodun A. Adesiyun Geoff T. Fosgate Anil Persad Mervyn Campbell Ravi Seebaransingh Alva Stewart-Johnson 《Tropical animal health and production》2010,42(8):1685-1694
The preliminary study was conducted to assess the virulence of a strain of Brucella abortus (1969D) and to compare the susceptibility of water buffalo and cattle calves to infection by the intraconjunctival route.
Seven of each cattle and water buffalo (Bubalus bubalis) calves aged 3–6 months were inoculated intraconjunctivally with counts ranging from 1.5 × 107 to 1.7 × 1010 colony forming units of B. abortus. Animals were monitored over an 8-week period for clinical manifestations and serological and hematological evidence of infection.
At slaughter, eight lymph nodes from each animal were sampled for bacteriological and histopathological assessments. Lymph
nodes from three water buffalo (43%) and five cattle (71%) yielded B. abortus (P = 0.048). Parotid/prescapular lymph nodes were most sensitive in detecting B. abortus. Our data suggest that B. abortus strain 1969D may be used as challenge strain, and water buffalo appeared to have a lower susceptibility to B. abortus infection than cattle. 相似文献
79.
Shahbazfar AA Mardjanmehr SH Arab HA Rassouli A Abdollahi M 《Tropical animal health and production》2011,43(4):843-849
Artemisinin has been used for centuries to treat malaria, intestinal tract helminthosis, diarrhea, and used as an antipyretic
and sedative agent, but the usage in veterinary medicine is a new field. Recently, it has been used successfully to control
experimental poultry coccidiosis. The present study aimed to determine the effects of different doses of artemisinin in broiler
chickens with chronic usage. Sixty birds divided into one control and four treatment groups that fed rations mixed with artemisinin
at doses of 17, 34, 68, and 136 ppm for 36 days. During the experiment, birds showed no clinical signs except anemia. In microscopic
examinations, heart, lung, and spleen had no lesion, but liver, kidney, and brain showed various lesions. Degenerative lesions
like intracytoplasmic eosinophilic inclusions were seen in both kidney and liver but fatty change was seen only in liver.
There was no relationship between severity of the liver lesions and drug dosage. Central chromatolysis, scattered neuronal
necrosis, and mild spongy changes were observed in five regions of the brain that were chosen for sectioning (motor cortex,
cerebellar nuclei, midbrain nuclei, and hindbrain nuclei at two separate levels). Severity of lesions in brain was dose-dependent,
and cerebral cortex was the most vulnerable area. Haematologic tests showed lower values for hematocrit and red blood cell
count dose-dependently. In conclusion, artemisinin is a promising drug for prevention and control of coccidiosis in broiler
chickens and its side effects are not too much serious especially at therapeutic doses. 相似文献
80.