Veterinary aspects of ecological monitoring: the natural history of emerging infectious diseases of humans,domestic animals and wildlife

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.     

Molecular cloning and expression analysis of a CXC chemokine gene from large yellow croaker Pseudosciaena crocea

In the present study, we report the cloning of a CXCL12 chemokine gene homologue from the large yellow croaker Pseudosciaena crocea (LycCXCL12). The complete cDNA of LycCXCL12 is 678 nucleotides (nt) encoding a protein of 97 amino acids (aa), with a putative molecular weight of 11.1 kDa. The deduced LycCXCL12 contains a 22-aa signal peptide and a 75-aa mature polypeptide, which possesses the typical arrangement of four cysteines as found in other known CXC chemokines. It shares 57-68% and 32-36% aa sequence identities to known CXCL12 chemokines in fish species and other vertebrates, respectively. The LycCXCL12 gene was constitutively expressed in all tissues examined although at different levels. Upon induction with poly(I:C) or inactivated trivalent bacterial vaccine, LycCXCL12 gene expression was significantly up-regulated in gills, liver, kidney, spleen and blood at 24 h after stimulation. Time course analysis using real-time PCR showed that LycCXCL12 gene expression reached peak level in spleen and kidney at 12 h or in gills at 24 h post-induction by poly(I:C), while its expression increased to the highest level in kidney at 24h or in gills and spleen at 48 h post-induction by bacterial vaccine, indicating that LycCXCL12 gene expression was differentially regulated by poly(I:C) and bacterial vaccine.     

应用单引物PCR指纹技术分析Vc-獭兔的分子遗传结构

采用1条小卫星引物M13(5’GAGGGTGGCGGTTCT3’)和2条微卫星引物(GTG)5、(GACA)4，对Vc—Ⅰ系、Vc—Ⅱ系獭兔、日本大耳白兔(JWR)和青紫蓝(QZL)4个品系各8只，总计32个个体的遗传结构进行了DNA指纹分析。结果，3条引物的扩增产物都呈现良好的多态性和稳定性；对每个品系混合DNA池进行分析，计算出了4个品系间及32个个体间的共有带率及遗传距离指数，通过聚类分析，得出各品系间和个体间欧式遗传距离，并绘制出4个品系间及各品系32个个体问的亲缘关系树状聚类图，从而初步建立了4个品系兔的SPAR指纹图谱。     

水解蜂蛹蛋白对大鼠免疫功能的影响

为了研究水解蜂蛹蛋白对大鼠免疫功能的影响及性别之间的差异,选用50只3周龄SD大鼠随机分成2组,分别灌胃蜂蛹蛋白粉和经消化酶水解的蜂蛹蛋白4周.结果表明,饲喂水解蜂蛹蛋白雌鼠胸腺指数比对照组提高30.00%(p＜0.05),雄鼠脾脏指数比对照组提高8.33%(p＜0.05),而雌鼠脾脏指数和雄鼠胸腺指数与对照组无显著差异.饲喂水解蜂蛹蛋白组雌鼠和雄鼠血清IgG的含量分别比对照组增加21.82%(p＜0.05)和41.34%(P＜0.05);雌鼠血清IgA含量比对照组增加52.78%(0＜0.01).结果提示,水解蜂蛹蛋白有增强大鼠的免疫功能的作用,且存在一定的性别差异.     

Socio-economic factors influencing control of vector-borne diseases in the pastoralist system of south western Uganda

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.     

Acaricidal activity of extracts of neem (Azadirachta indica) oil against the larvae of the rabbit mite Sarcoptes scabiei var. cuniculi in vitro

The acaricidal activity of the petroleum ether extract, the chloroform extract and the acetic ether extract of neem (Azadirachta indica) oil against Sarcoptes scabiei var. cuniculi larvae was tested in vitro. A complementary log-log (CLL) model was used to analyze the data of the toxicity tests. The results showed that at all test time points, the petroleum ether extract demonstrated the highest activity against the larvae of S. scabiei var. cuniculi, while the activities of the chloroform extract and the acetic ether extract were similar. The activities of both the petroleum ether extract and the chloroform extract against the larvae showed the relation of time and concentration dependent. The median lethal concentration (LC(50)) of the petroleum ether extract (1.3muL/mL) was about three times that of the chloroform extract (4.1muL/mL) at 24h post-treatment. At the concentrations of 500.0muL/mL, the median lethal time (LT(50)) of the petroleum ether extract and the chloroform extract was 8.4 and 9.6h, respectively.     

生地提取物对雏鸡免疫器官指数和H9疫苗免疫效果的影响

本试验旨在研究生地提取物对雏鸡免疫器官发育和H9疫苗效果的影响,采用单因素分组设计,选用1 200只1日龄雏鸡,随机分为6组,生地提取物添加组（Ⅰ、Ⅱ、Ⅲ组）分别在基础日粮中添加1‰、2‰、3‰生地提取物,黄芪多糖组（Ⅳ组）在基础日粮中添加0.4‰黄芪多糖,免疫不给药组（Ⅴ组）免疫H9疫苗并饲喂基础日粮,空白组（Ⅵ组）不免疫H9疫苗并饲喂基础日粮,药物添加期为7 d,分别在雏鸡14、21、28、35、42、49、56日龄进行采样,测定鸡群的H9抗体水平,计算法氏囊和脾脏的脏器指数。结果显示：①与Ⅵ组相比,Ⅰ、Ⅱ、Ⅲ、Ⅳ组均能显著提高雏鸡脾脏和法氏囊指数（P < 0.05）,促进雏鸡的脾脏和法氏囊的生长发育,其中,Ⅱ组（2‰生地提取物）的脾脏指数和法氏囊指数较Ⅰ、Ⅲ组显著提高（P < 0.05）,且Ⅱ组与Ⅳ组无显著差异（P > 0.05）。②黄芪多糖和生地提取物的添加可提高雏鸡血清禽流感疫苗抗体效价并且使H9抗体维持在较高水平（log2）,从42日龄起,Ⅱ组的抗体滴度显著高于Ⅰ、Ⅲ组（P < 0.05）,同时与Ⅳ组无显著差异（P > 0.05）。综上所述,生地提取物具有促进雏鸡的脾脏和法氏囊发育的作用,配合H9疫苗使用,可以维持抗体处于较高滴度,建议生地提取物在雏鸡日粮中的添加剂量以2‰为宜。     

Demographic dynamics and off-take of cattle herds in southern Mali

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.     

Improvement of trivalent leptospira vaccine by removal of anaphylactic agents

The anaphylactic reactions in cattle following leptospira vaccination mostly booster dose in different parts of Iran have been reported. The serum proteins as allergic substances are components of liquid phase of the vaccine. Therefore, the vaccine was modified by washing the whole cultures by centrifugations. The modified vaccine was safe in laboratory animals and cattle as well as under field conditions. Microagglutination test revealed a similar pattern of antibody response to the three Leptospira interrogans serovars (Canicola, Grippotyphosa, and Sejro hardjo) in all vaccinated cattle groups while was higher than the response of control animals. The results of the present investigation revealed that we can minimize postvaccination shock in vaccinated cattle populations with removing the shock proteins.