共查询到20条相似文献,搜索用时 15 毫秒
1.
Wambura P.N. Mollel J.O. Moshy D.W. Mbise A.N. Taylor W.P. 《Tropical animal health and production》1999,31(1):9-14
In January 1997, serum samples from 1346 adult sheep and goats were tested by a competitive ELISA to determine the prevalence of rinderpest in the northern zone of Tanzania. Seroconversion rates of 20%, 13%, 9%, 7% and 3% in sheep and goats were recorded in Ngorongoro, Monduli, Hai, Arumeru and Simanjiro districts, respectively. The low profile and insidious nature of the rinderpest virus involved caused very mild disease in cattle in some of these area. The mild signs associated with this outbreak of rinderpest resulted in difficulty in its diagnosis. In these circumstances, the presence of rinderpest antibody in sheep and goats served as a valuable and effective indicator of the rinderpest outbreak in cattle. 相似文献
2.
Wambura PN Moshy DW Mbise AN Mollel GO Taylor WP Anderson J Bruning A 《Tropical animal health and production》2000,32(3):141-145
A simple chromatographic strip-test based on Clearview technology, is under development as a pen-side test for the detection of rinderpest antigen in eye swabs taken from cattle in the field. An outbreak of rinderpest occurred in the northern zone of Tanzania from late February to June 1997. The affected cattle exhibited very mild clinical signs, which made clinical diagnosis difficult. One hundred and seven eye swabs were collected from cattle suspected of infection with rinderpest. These were tested in the field using a prototype of the pen-side test and 13 (12.15%) of the samples were found to be positive for the presence of rinderpest antigen. These were confirmed by ICE. The positive cases were predominantly found in the Ngorongoro district. This demonstrates the usefulness of such a simple, rapid pen-side diagnostic assay, particularly when clinically `mild' strains of rinderpest are present. 相似文献
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Taylor WP Roeder PL Rweyemamu MM Melewas JN Majuva P Kimaro RT Mollel JN Mtei BJ Wambura P Anderson J Rossiter PB Kock R Melengeya T Van den Ende R 《Tropical animal health and production》2002,34(6):471-487
In January 1997, Tanzania requested international assistance against rinderpest on the grounds that the virus had probably entered the country from southern Kenya. Over the next few months, a variety of attempts were made to determine the extent of the incursion by searching for serological and clinical evidence of the whereabouts of the virus. At the clinical level, these attempts were hampered by the low virulence of the strain, and at the serological level by the lack of a baseline against which contemporary interpretations could be made. Once it became apparent that neither surveillance tool was likely to produce a rapid result, an infected area was declared on common-sense grounds and emergency vaccination was initiated. The vaccination programme had two objectives, firstly to prevent any further entry across the international border, and secondly to contain and if possible eliminate rinderpest from those districts into which it had already entered. On the few occasions that clinical rinderpest was subsequently found, it was always within this provisional infected area. Emergency vaccination campaigns within the infected area ran from January to the end of March 1997 but were halted by the onset of the long rains. At this time, seromonitoring in two districts showed that viral persistence was still theoretically possible and therefore a second round of emergency vaccination was immediately organized. Further seromonitoring then indicated a large number of villages with population antibody prevalences of over 85%. These populations were considered to have been `immunosterilized'. Although no clinical disease had been observed in them, it was decided to undertake additional vaccination in a group of districts to the south of the infected area. Serosurveillance indicated that rinderpest could have been present in a number of these districts prior to vaccination. Serosurveillance in 1998 suggested that numerous vaccinated animals had probably moved into districts outside the infected and additional vaccination areas, but did not rule out the continued presence of field infection. 相似文献
4.
Effect of Vaccination with Brucella abortus Strain RB51 on Heifers and Pregnant Cattle 总被引:1,自引:0,他引:1
Uza FA Samartino L Schurig G Carrasco A Nielsen K Cabrera RF Taddeo HR 《Veterinary research communications》2000,24(3):143-151
Thirteen cows, which had been vaccinated as calves with strain 19, were revaccinated twice or three times as adults with 1×109 cfu of B. abortus strain RB51. Their serological responses following adult vaccination remained negative to conventional brucellosis surveillance tests. Vaccination with strain RB51 during the eighth month of pregnancy did not induce abortion, although strain RB51 was recovered from milk for up to 69 days after vaccination. In a parallel study, thirteen 8- to 10-month-old heifers were vaccinated as calves with 109 cfu of strain RB51. The heifers remained seronegative to conventional brucellosis surveillance tests but antibody responses to RB51 could be demonstrated using an indirect ELISA. This study showed that multiple vaccination with strain RB51 did not induce seroconversion to brucellosis surveillance tests. In addition, this study suggests that 109 cfu of strain RB51 is safe for use in pregnant cattle. 相似文献
5.
Plasmid vaccine pBK-CMVMP1LC113 expressing the matrix (M) gene of rinderpest virus was assessed for its potential to protect rabbits against a lethal viral challenge. Rabbits immunized with plasmids expressing the M gene were not protected when challenged with lapinized rinderpest virus, despite the production of anti-M antibodies, while rabbits immunized with rinderpest tissue culture vaccine were completely protected from a lethal challenge with lapinized rinderpest virus. The plasmid vaccine also had no significant effect on the lymphopenia in challenged rabbits. The results indicate that rinderpest M protein does not have a protective role in rinderpest infection. 相似文献
6.
Van den Bossche P Shumba W Njagu C Shereni W 《Tropical animal health and production》2001,33(5):391-405
Tsetse have been cleared from large areas of Zimbabwe during the past 65 years. In most areas, they are prevented from re-invading cleared areas by barriers of odour-baited, insecticide-treated targets. A trypanosomosis survey was conducted to determine the effectiveness of such barriers against re-invasion and to confirm the absence of tsetse in areas where they had previously been eradicated. Parasitological diagnostic methods and an anti-trypanosomal antibody detection enzyme-linked immunosorbent assay (antibody ELISA) were used. The prevalence of trypanosomal infections in the tsetse-cleared areas was generally low. However, the prevalence of anti-trypanosomal antibodies was unexpectedly high in some areas. This high proportion of cattle with antibodies could, in most cases, be explained by recent or historic information on the distribution and density of tsetse. The results from the survey demonstrated the value of anti-trypanosomal antibody detection as an additional sensitive tool for monitoring the effectiveness of tsetse control operations. 相似文献
7.
Van den Bossche P Munsimbwe L Mubanga J Jooste R Lumamba D 《Tropical animal health and production》2004,36(1):33-43
A trial to evaluate the efficacy of a 1% cyfluthrin pour-on formulation (Cylence, Bayer) in reducing the incidence of bovine trypanosomosis was conducted in an area of ca. 2000 km2 of the Eastern Province of Zambia. The trial area was cultivated and carried a cattle population of approximately 11 animals/km2. Cattle were the main host of tsetse. Following the free of charge treatment of the adult cattle at intervals of 7 weeks and at a dosage of 15 ml/100 kg body weight, there was an increase in the average packed cell volume in the herd although the decline in the incidence of trypanosomal infections was more prolonged. The monthly incidence of trypanosomal infections started to decline substantially 8 months after the treatments were initiated. No trypanosomal infections were detected from 10 months after the start of the trial. 相似文献
8.
Kamuanga M Sigué H Swallow B Bauer B d'Ieteren G 《Tropical animal health and production》2001,33(2):141-153
Interviews with all the households in the Agropastoral Zone (ZAP) of Yalé, southern Burkina Faso, were conducted in 1994 and again in 1997 to assess the impacts of a tsetse control programme implemented from 1994, using insecticide-impregnated targets and pour-on treatments of all cattle with deltamethrin 1%. In the absence of health and productivity monitoring, data were collected in single-visit surveys in order to generate quantitative estimates of relevant reproductive performance variables for cattle and to assess changes in the inputs used and outputs produced. The results indicate a 25% increase in herd size and an increase in the number of oxen from 0.1 to 1.1 per household; a reduction in mortality from 63.1% to 7.1% and reductions in the rates of abortions and stillbirth of 55.9% and 51.3%, respectively; and an increase in the rate of live births of 57.6% and in the milk yield from 0.2 to 2.2 litres/cow per day in the dry season. These results show the dramatic impacts that trypanosomosis control can have on Zebu cattle exposed to high tsetse challenge. Well-designed surveys can be a cost-effective way to obtain estimates of productivity impacts that can be used to simulate projections of herd growth and meat and milk production in herd models. While there are many confounding factors associated with farmers' perception of a gain in productivity, these estimates form a useful alternative to subjective assessments in modelling the economic benefits of tsetse and trypanosomosis control. 相似文献
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A Comparison of Methods for Measuring the Antibody Response in Mice and Cattle following Vaccination against Food and Mouth Disease 总被引:1,自引:0,他引:1
Dus Santos MJ Wigdorovitz A Maradei E Periolo O Smitsaart E Borca MV Sadir AM 《Veterinary research communications》2000,24(4):261-273
We present a comparison of methods for evaluating the potency of foot and mouth disease vaccine in the laboratory. The anti-FMDV antibodies (Ab) in vaccinated mice were tested by liquid phase (lp) ELISA, solid phase (sp) ELISA and virus neutralization (VN), and were compared with the Ab titres detected by lpELISA, which is the official test in Argentina for testing the potency of FMD vaccines and protection against a virulent challenge in cattle. The results demonstrated that it is possible to relate the Ab levels induced in vaccinated mice with both the Ab and protective responses elicited in cattle. Furthermore, it was found that the anti-FMDV Ab titres in mice detected by lpELISA 14 days after vaccination should be an accurate parameter for predicting the results of the challenge test in cattle. Thus, this test in mice appears to be an inexpensive and rapid alternative for testing FMD vaccines in cattle. 相似文献
11.
The prevalence of trypanosomosis, mean packed cell volume and anti-trypanosomal antibody levels in village cattle of different age groups (<0.5 year, 0.5–2 years, >2–5 years and >5 years) in the areas with tsetse control were compared with those of corresponding age groups in areas without tsetse control in Tororo, southeast Uganda. The prevalence of trypanosomosis in cattle in the age groups of 0.5–2 years, >2–5 years and >5 years in the areas with tsetse control was significantly lower than in cattle in similar age groups in the areas without tsetse control (p<0.5). Trypanosoma vivax was the most predominant Trypanosoma species in the areas with tsetse control, while T. congolense was the most predominant species in the areas without tsetse control. The mean Trypanosoma antibody levels in cattle in the age groups <0.5 year, 0.5–2 years and >2–5 years in the areas with tsetse control were significantly lower than those of the similar age groups in the areas without tsetse control (p<0.5). The mean PCV values for cattle in the age groups 0.5–2 years, >2–5 years and >5 years from the areas with tsetse control were significantly higher than those of the similar age groups in the areas without tsetse control. Tsetse control appeared to have a considerable impact on the prevalence of trypanosomosis, distribution of Trypanosoma species, specific antibody levels and the packed cell volume of cattle in the different age groups. 相似文献
12.
This study was conducted in Masaba and Masafu Sub-counties, Busia District, Uganda to assess the effect on the tsetse fly population of first treating all cattle with 1% w/v deltamethrin pour-on for a few months, followed by treating 10% of the cattle population. Treatment of all cattle for 6 months resulted in a significant reduction in the density of tsetse flies from 6.3 to 0.1 flies/trap/day (FTD), a 98.4% reduction. During the same period, the point prevalence of bovine trypanosomosis dropped from 37.7% to 2.9% (a 92.3% reduction). Treatment was resumed six months later, but this time only 10% of the cattle population received the pour-on treatment at three week intervals for a period of one year. This treatment maintained the tsetse fly density between 0 and 0.5 FTD and the prevalence of bovine trypanosomosis generally remained below 10%. In conclusion, under the local prevailing conditions, treatment of all communally grazed cattle with deltamethrin pour-on effectively suppressed the Glossina fuscipes fuscipes population. However, subsequent treatment of 10% of the cattle probably failed to control the tsetse fly population at a level sufficient to reduce trypanosomosis to acceptable levels. 相似文献
13.
西北地区养牛业进展 总被引:1,自引:1,他引:0
我国西北地区包括陕、甘、青、宁、新五省区,总土地面积296.6万km2,占全国的30.9%,人口占7.23%.2003年末存栏黄牛1 333.9万头,奶牛253.0万头,分别占全国相应牛数的13.4%和28.3%;总产牛肉60.8万t,牛奶270.1万t,分别占全国产量的9.6%和15.5%;奶牛平均每头年产奶1 068 kg,为同期全国平均每头产奶量(1 955 kg)的54.6%,出栏牛产肉量平均每头120.3 kg,为全国平均每头出栏牛产肉量(134.0 kg)的89.9%.新疆是西北地区的牛肉、牛奶生产大区,产量分别占西北区总产量的47.3%和41.8%.甘肃、青海、新疆是我国传统牧区,可发展与其草原改良相适应的低成本养牛业.西北区养牛科技进步对养牛业发展起到推动作用,遗传改良、胚胎移植、黄牛选育、高产奶牛培育、饲草基地建设等都取得了显著进展. 相似文献
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近年来,通渭县引进大量的良种肉牛冻精,冻配改良了本地肉牛,为提高肉牛杂交改良效果,提高单体经济效益,增加农户养牛收入。对引进的肉牛杂交改良本地肉牛进行了试验研究。在通渭县以夏洛来为父本、西本杂交牛为母本,杂交一代肉牛初生重达到36.4 kg,平均日增重达到689.3 g,18月龄夏西本体高18月龄达到146.4 cm,体斜长达到158.8 cm,胸围达到192.8 cm,管围达到20.2 cm。18月龄夏西本体高比利西本高15.8%,体斜长比夏利本高14.7%,胸围比利西本高17.0%,管围比夏利本和利西本高5.7%。因此以夏洛来为终端父本,西门塔尔与本地黄牛杂交F_1为母本,进行杂交改良,其生长速度快,个体较大,能快速提高三元杂交肉牛经济效益。 相似文献
16.
A study to compare the profitability of rearing sheep and goats under natural trypanosomosis challenge was carried out on Galana ranch in south-eastern Kenya between July 1996 and October 1997. Seventy-nine male weaner sheep and 79 male weaner goats were monitored monthly for weight changes and fortnightly for trypanosomosis. The animals of each species were divided into two groups. Group 1 was an untreated control, while group 2 was treated with isometamidium chloride (Samorin) at 0.5 mg/kg body weight every 3 months. In both groups, trypanosome infections were detected by microscopy and treated with diminazene aceturate (Veriben), at 3.5 mg/kg body weight, when the packed cell volume reached 17% or below. The profitability of each drug regime was expressed as the marginal revenue over the cost of trypanosomosis (MOT). There were greater losses occasioned by trypanosomosis in sheep than in goats. Animals of both species on chemoprophylaxis gave higher MOT values than those that received chemotherapy on diagnosis. However, the MOT values for the chemoprophylactic regime were higher for sheep than for goats, suggesting that the greater weight gain by sheep more then compensated for the higher cost of maintaining them under high trypanosomosis challenge. Thus, a Galana rancher would be better off keeping sheep rather than goats, other things being equal. The marginal revenue per dose of Samorin was lower than that of Veriben for both species, suggesting that strategic use of Samorin timed to precede the peak incidence of trypanosomosis might be a better option to raise the overall profitability in sheep and goats. 相似文献
17.
为优化颗粒细胞单层共培养体系,实验研究了颗粒细胞单层体外培养时间、颗粒细胞单层的种属及更换培养单层时间对黄牛孤雌胚胎体外发育的影响。结果表明:将培养0、2d和4d后的颗粒细胞单层用于胚胎的体外共培养,3组的卵裂率和囊胚率分别为84.47%/40.23%、78.49%/36.99%和71.55%/25.30%;来自黄牛、小鼠和猪的颗粒细胞单层在支持黄牛孤雌胚胎体外发育方面无显著差异(P>0.05);第4天更换培养单层的囊胚率最高(55.17%),与不更换单层的对照组(41.25%)有显著差异(P<0.05)。 相似文献
18.
Greco A Loria GR Dara S Luckins T Sparagano O 《Veterinary research communications》2000,24(7):471-475
Veterinary Research Communications - 相似文献
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