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1.
A survey was conducted to identify tick species and determine the prevalence of tick infestation in small ruminants of Miesso District, West Harergie Zone. Collection and identification of the ticks were undertaken from November 2007 to April 2008. All visible individual adult ticks were collected from the body of 328 goats and 40 sheep. The prevalence of tick infestation in goats and sheep was found to be 89.9% and 87.5%, respectively. In this study, ten species of ticks which grouped under four genera were identified. The most abundant species found in this study were Boophilus decoloratus (60%), Rhipicephalus pulchellus (25.1%), and Amblyomma gemma (11%). Hyalomma dromedarii was the minor species observed on goats. The difference in the prevalence of tick infestation between sheep and goats was not statistically significant (Χ 2   = 0.22, p = 0.63) but found to be statistically significant between male and females (Χ 2  = 9.8, p = 0.003). Attention should be given to the control and prevention of ticks, since they cause sever damage to the skins of small ruminants and thereby reduce the foreign exchange of the country; they also transmit some diseases which can cause sever loss to the productivity of these animals.  相似文献   

2.
The seasonal occurrence of Karoo paralysis in relation to the infestation density of female Ixodes rubicundus was investigated in an enzootic area of the southwestern Orange Free State, South Africa. Young and adult Angora goats were exposed to infestation during two paralysis tick seasons. Only the young goats became paralysed and their infestation densities (female ticks kg-1 host body weight) were significantly higher than those of healthy animals. The infestation densities on paralysed goats varied between 0.64 and 3.56 ticks kg-1. During the 1988 season, 30% of the naive young goats became paralysed compared with 67% the following season. Twenty-nine percent of previously paralysed goats were paralysed again during the same season. Paralysis occurred during periods of peak tick activity (April-June).  相似文献   

3.
This paper reports further results of a two year livestock mortality survey in Afghanistan, where a war of more than a decade had completely disrupted the veterinary field services. A questionnaire-based survey to measure the impact of a veterinary field programme indicated that average annual mortality in cattle, sheep, and goats was substantially lower in districts that received veterinary services (covered districts) than in districts without any veterinary services (control districts). The impact of the programme varies according to the season and the age group of the animals involved. The programme lacked impact in winter, in particular in adult small ruminants. The highest impact was noted in the spring and autumn for adult goats, and summer and autumn for adult sheep.The impact of the programme was also limited (in small ruminants even completely absent) during the suckling period in young animals. The highest impact was noted in the post-weaning period in small ruminants, when approximately four times more lambs and kids died in the control districts than in the covered districts.It was concluded that the major impact of the veterinary programme was achieved when animals are in contact with other flocks during grazing seasons, when parasitic and infectious diseases are present and against which the veterinary programme is directed. Additional inputs – including extension activities – are therefore required to improve the effect of the programme in the winter and in the neonatal period.  相似文献   

4.
Trypanosome infections, packed red cell volume levels (PCV), body weight and nematode faecal egg counts of village-based small ruminants were monitored in two areas in The Gambia with either moderate or high trypanosomosis risk for 24 and 30 months respectively. Outflows from the flock and new-born animals were recorded and data on housing and management were compiled. Reported mortality rates were higher in goats than in sheep, but for both species highest in the moderate risk area. The peak of trypanosome infections lagged the peak of tsetse densities by 1-3 months in both areas. Trypanosoma vivax was the predominant species found in the infected animals, followed by T. congolense. Trypanosome prevalence was, in general, higher in sheep than in goats but only significantly higher during Year 1 in the moderate risk area. Trypanosome infection reduced the PCV level significantly and seasonal effects indicated significantly lower PCV levels during the rains. Trypanosome infection significantly depressed weight gain in both species at periods where infection rates were highest. In both species considerably lower weight gains were observed during the rainy season. Abortion rates were higher in goats than in sheep in both study sites, and highest in the high-risk site. Trypanosome infection in ewes in the high risk area increased lamb mortality significantly but had no effect on birth weights, nor on growth rates up to 4 months. Offspring mortality up to 4 months was generally high at both sites. Trypanosome infection in the dam between 3.5 to 7 months post parturition significantly increased parturition interval in both species. Peak faecal egg output occurred at the end of the rainy season and was highest for both species in the moderate risk site. Poor grazing management was found responsible for a seasonal nutritional constraint. Based on these results, these breeds of sheep and goats can be considered as trypanotolerant since they are able to remain productive under high and moderate levels of trypanosome challenge. Nevertheless, trypanosomosis affected their health and production level as shown by reduced PCV levels, depressed weight gains, longer parturition intervals and higher lamb mortality. In addition, during the rains, helminth infections and poor management leading to nutritional constraints had also a negative impact on health and production and therefore influenced the innate resilience to trypanosomosis in those indigenous breeds. Adaptations in management may have an equal impact as certain disease control measures to improve biological and economical returns from small ruminants in tsetse infested rural areas.  相似文献   

5.
Giemsa-stained thin blood smears prepared monthly from cattle, sheep and goats in the Greater Accra region of Ghana between May 1994 and December 1996 were examined for presence of tick-borne haemoparasites. The majority of animals were less than 2 months old at the start of the survey. Monthly and cumulative incidences are presented of Anaplasma sp., Babesia bigemina, Borrelia sp., Eperythrozoon sp., Theileria mutans and Theileria velifera in cattle, Anaplasma sp., Borrelia sp., and Theileria sp. in sheep, and Anaplasma sp. in goats. T. mutans was the commonest parasite in cattle, with 100% incidence in calves by 10 months of age, and Anaplasma was commonest in small ruminants. The relative prevalence of these haemoparasites in blood smears from cattle, sheep and goats sampled on a single occasion at sites in all 10 regions of Ghana was found to be similar, though actual infection rates were lower. Packed cell volume (PCV) measurements from the sampled animals are also presented; no seasonal trends were evident in the PCV of the cattle, sheep and goats sampled monthly. In animals sampled on a single occasion, mean PCV was significantly higher in cattle and sheep without detectable haemoparasite infection, and in cattle was lowest in animals positive for both Babesia and Anaplasma, while there was no difference in mean PCV levels between parasitised and non-parasitised goats.  相似文献   

6.
Monoclonal antibody-based competitive ELISA (C-ELISA) has been used for the specific measurement of antibodies to peste des petits ruminants (PPR) viruses in sheep, goats, cattle and Buffalo. Serum samples from sheep (n = 232), goats (n = 428), cattle (n = 43), buffalo (n = 89) were tested. The animals had not been vaccinated against rinderpest or PPR. Findings suggested that the sero-positive cases were significantly higher in sheep (51.29%) than in goats (39.02%) (P = 0.002). The overall sero-prevalence of PPRV in small ruminants was 43.33%. The PPR antibodies seroprevalence was 67.42% in buffalo and 41.86% in cattle which was significantly higher in buffalo (P = 0.005). The overall sero-prevalence of PPRV in large ruminants was 59.09%. Cattle and buffalo sera showed a high prevalence of antibody against PPR virus which may explain the difficulty experienced in achieving high post-vaccination immunity levels against rinderpest. Because antibodies against PPR virus are both cross-neutralizing and cross-protective against rinderpest virus, further vaccination in the presence of antibodies against PPR virus may be a waste of national resources. It was also suggested that antibodies to PPR virus could prevent an immune response to the rinderpest vaccine. This paper presents serological evidence for the transmission of PPR virus from sheep and goats to cattle and buffalo and highlights the need to include PPR serology in the sero-monitoring programme to give a better indication of national herd immunity of sheep and goats against PPR.  相似文献   

7.
隐孢子虫是可以感染小反刍动物的肠道原生生物,具有潜在的公共卫生学问题。隐孢子虫可引起人和动物的腹泻和肠道疾病,严重情况下会出现死亡。被感染的动物可能是人畜共患型隐孢子虫的宿主,可引起公共卫生风险、农场利润减少和动物福利等问题。隐孢子虫病已被报道是新生牛、羊等反刍动物腹泻和死亡的一个重要原因,认为是新生羔羊腹泻的第二大诱因,仅次于轮状病毒。羊隐孢子虫病在世界范围内都有发现,不同程度地威胁着人和动物的身体健康,基于此,现就隐孢子虫对羊感染的危险因素和常用检测方法,以及我国羊感染的现状进行综述,为其防控提供参考。  相似文献   

8.
Faecal samples were obtained from sheep and goats before, during and after the rainy season at three locations in south-west Mauritania. Several animals were also necropsied at the same time.Haemonchus contortus was the most prevalent worm. Infection by digestive-tract strongyles andStrongyloides papillosus was always very light (prevalence less than 20%). Sheep were more heavily infected than goats but animals under 1 year of age were not infected by digestive-tract strongyles. It is likely that young small ruminants became infected during the rainy season and that the parasites so acquired are inhibited in their development and/or survive nearly one year as adults.  相似文献   

9.
Trypanosomosis is a major impediment to livestock production and economic development in those areas of Africa where it is endemic. Although small ruminants appear to perform better than cattle in various agro-ecological zones, the importance of trypanosomosis has not been extensively investigated in these livestock. This study was designed to investigate the prevalence of trypanosomosis in sheep and goats in an endemic area and to evaluate the performance of different breeds under high tsetse challenge and the potential role of chemoprophylaxis in the control of the disease. The results showed that tsetse flies feed readily on small ruminants, and that these animals are susceptible to trypanosomosis. The Small East African goats acquired fewer infections than the Black Head Persian and Dorper sheep used in the study. In both sheep and goats, chemoprophylaxis with isometamidium chloride (Samorin, Rhone Merieux, Annecy, France) was protective, resulting in fewer infections and higher body weight gain. Trypanosomosis caused anaemia in both sheep and goats, and animals whose PCV fell below 15% rarely recovered, even with trypanocidal drug treatment. The peak transmission period was between 1 and 3 months after the peak tsetse fly density, which raises the possibility of effective strategic prophylaxis.  相似文献   

10.
Data on reproduction and mortality were collected over one year from 5100 sheep and 13 300 goats in treated and control flocks. The treated animals received vaccination against peste des petits ruminants (PPR) and anthelmintics twice a year. Productivity parameters (fecundity and mortality rates) obtained with and without prophylaxis were fitted into a benefit–cost economic analysis model and run for project lifespans varying from one to five years. At a 7% discount rate, the overall benefits for a project lifespan of five years were estimated as over 15 million FCFA and 11 million FCFA for sheep and goats, respectively. The benefit–cost ratio ranged from 2.26 to 3.27 in goats and 3.01 to 4.23 in sheep, depending on the project lifespan. It was concluded that PPR and gastrointestinal helminthosis are important causes of economic losses in small ruminants in Cameroon. A national or even a regional vaccination campaign against PPR and strategic anthelmintic treatment of small ruminants are recommended.  相似文献   

11.
Tick-borne fever (TBF) is a rickettsial disease of domestic and wild ruminants in temperate climates where the hard tick Ixodes ricinus is present. The disease is characterized by a high temperature and severe leukopenia. In the present study, the effects of TBF on the activity of serum alkaline phosphatase (ALP), and on the concentrations of plasma zinc, iron, total bilirubin, urea, creatinine and albumin were investigated by inoculating one group of eight sheep and one group of eight goats with the Old Sourhope (OS) strain of Ehrlichia (Cytoecetes) phagocytophila. All goats and sheep experimentally infected with E. phagocytophila reacted with fever, rickettsiaemia and leukopenia. The leukopenia was due to an acute lymphocytopenia and prolonged neutropenia. In both groups of animals. TBF was characterized by significant reductions in the activities of serum ALP and concentrations of plasma zinc, iron and albumin. However, there were significant increases in the concentrations of plasma total bilirubin, urea and creatinine in both species of animals. The reductions in ALP and iron were significantly more pronounced in sheep than in goats.  相似文献   

12.
We report Marie Galante as one of the Caribbean islands most heavily infested by the tropical bont tick (TBT) Amblyomma variegatum which is associated with two major diseases of ruminants: heartwater and dermatophilosis. In 2005, a survey was undertaken to assess the prevalence of TBT infestation in cattle, the prevalence of Ehrlichia ruminantium infection in TBTs, and the tick control measures implemented by livestock owners. A random sample of 195 cattle herds out of 1885 recorded on the island was investigated by thoroughly counting adult ticks on each animal and filling a questionnaire. A randomly collected sample of 136 TBTs was tested for infection by E. ruminantium by pCS20 nested PCR. Cattle herd prevalence (hp) was 73.8% for infestation by at least one TBT, 17.9% for infestation by at least one engorged female TBT, and 8.2% for clinical dermatophilosis. Cattle individual prevalence was 42.3% for infestation by at least one TBT, 6.6% for infestation by at least one engorged female TBT, and 2.2% for clinical dermatophilosis. The minimum, maximum and average numbers of TBTs per infested animal were, respectively 1, 108 and 11.5. Prevalence of TBT infection by E. ruminantium was 19.1%. No significant difference in herd prevalence was found among parishes or among ecological zones. For cattle owners treating against ticks (97.9% of all owners), all used aspersion of amitraz and herd prevalence was significantly different among those treating every 1-2-week (hp=69.6%, n=148), and less often than every 2-week (hp=88.6%, n=35) (P=0.031). Of the 42 herd subunits treated less than 4 days before the survey, 27 (64%) were infested with at least one TBT, and 6 (14%) with at least one engorged female TBT. These results indicate a high level of TBT infestation in Marie Galante, the inefficacy of tick treatments currently performed, and the need for an improved tick control strategy. Persisting high levels of infestation in Marie Galante threaten the success of on-going TBT eradication programs in the Caribbean because TBT can spread through migrating birds and trade of animals or of animal hides to other islands and potentially the American continent.  相似文献   

13.
Isometamidium chloride has been used for the control of trypanosomosis in animals for over 36 years, but recently there have been reports of prophylaxis failure under natural conditions. In this study, use of the drug for prophylactic purpose against trypanosomosis in small ruminants was investigated. Forty-two sheep and 44 goats were divided into four treatment groups. Groups 1 and 2 were treated with isometamidium chloride (Samorin, Rhone Merieux, Lyon, France) at 3-month intervals while groups 3 and 4 were used as controls. All the animals were exposed to natural tsetse challenge and monitored for serum isometamidium levels and anti-trypanosome antibodies. Seven days after drug administration, isometamidium levels were significantly higher in goats 13.7+/-0.07 ng/ml than in sheep 6.2+/-0.06 ng/ml. However, the elimination half-life in the sheep was 14.2+/-0.92 days and was significantly higher (P> 0.05) than that of the goats 12+/-0.5 days. This study established that isometamidium metabolism differs between sheep and goats and this difference may have important implications in high tsetse challenge areas.  相似文献   

14.
Village production of West African Dwarf goats and sheep in Nigeria   总被引：2，自引：2，他引：0  
Results from a 41 month study of West African Dwarf goats and sheep under village conditions in south-west Nigeria are reported. Even at a very low level of management these trypanosomiasis-tolerant animals produced 2.01 kids or 1.51 lambs per dam per year. Mortality of young particularly kids and low growth rates limit production. Of these mortality is probably the first constraint to increased productivity and profitability. Control of peste des petits ruminants appears to significantly reduce mortality and should stimulate the further development of this production system.  相似文献   

15.
Yin H  Luo J  Guan G  Lu B  Ma M  Zhang Q  Lu W  Lu C  Ahmed J 《Veterinary parasitology》2002,108(1):21-30
Experiments on the transmission of an unidentified Theileria sp. infective for small ruminants by Haemaphysalis qinghaiensis and Hyalomma anatolicum anatolicum were carried out. Three Theileria-free batches of adult, larvae, and nymphs of laboratory reared H. qinghaiensis and Hy. a. anatolicum ticks were infected by feeding them on sheep infected with Theileria sp. The Theileria sp. was originally isolated from adult ticks of H. qinghaiensis, by inoculation of blood stabilates or tick transmission. H. qinghaiensis has been shown to be capable of transmitting the Theileria sp. infective for small ruminants transstadially to sheep and goats. The nymphs developed from the larvae engorged on the sheep infected with the parasite transmitted the pathogen to splenectomized sheep with prepatent periods of 30, 31 days, respectively; but the subsequent adult ticks of H. qinghaiensis derived from the nymphs did not transmit the pathogen to sheep. However, adults developed from the nymphs engorged on the sheep infected with the parasite transmitted the pathogen to sheep with prepatent periods of 24-27 days. The larvae, nymphs and adult ticks derived from female H. qinghaiensis ticks engorged on infected sheep were not able to transmit the parasite transovarially. The same experiments were done with Hy. a. anatolicum, but examination for presence of piroplasma of Theileria sp. from all animals were negative, demonstrating that Hy. a. anatolicum could not transmit the organism to sheep or goats.  相似文献   

16.
To screen the host-dependent abundance of hard tick (Acari: Ixodidae) developmental stages on ruminants in South Hungary, red and roe deer, as well as goats and sheep were examined in a season, when larvae and nymphs are active. Altogether 2271 ticks were collected. In the relevant period the prevalence of tick-infestation was significantly higher among goats, than among sheep kept in the very same area, most likely in association with the browsing habit of the former. Roe deer and goats were found to be important hosts for Ixodes ricinus and Haemaphysalis concinna larvae, in contrast to the view that this stage does not usually feed on medium-sized mammals. Interestingly, one third of I. ricinus larvae and one larva of H. concinna and of Dermacentor reticulatus collected from goats in the same herd in August have started the moulting process (showed apolysis) on their host, despite being three-host ticks. This is the first survey involving four species of domestic and wild ruminants in Europe to compare the host-preference of ixodid ticks in the same region.  相似文献   

17.
Switzerland is controlling Transmissible Spongiform Encephalopathies (TSE) in cattle (BSE) and small ruminants (scrapie). Since BSE is potentially transmissible to sheep, goats or pigs through feeding of contaminated meat and bone meal, implementation of an active surveillance programme for TSE in these species is discussed. The aim of this pilot study was to obtain preliminary data on the prevalence ofTSE and other neurological disorders in these populations. For that purpose, a total of 398 perished and 825 slaughtered adult small ruminants and pigs was examined for the presence of neuropathological changes. None of these animals revealed positive for TSE. However, the investigations demonstrated that perished sheep and goats exhibited a higher prevalence of relevant neuropathological changes when compared with slaughtered animals. From these results, it is concluded that perished small ruminants are probably a risk population for TSE and should be considered as target populations for an active surveillance programme.  相似文献   

18.
A serological survey on dermatophilosis was carried out amongst sheep and goats in Kaduna State of Nigeria. Sera were obtained from slaughter animals and from sheep kept on an isolated ranch. The percentage of seropositive animals was 28.0 in slaughter sheep, 0.0 in sheep kept on the ranch, and 23.2 in slaughter goats. The high prevalence of D. congolensis antibodies among small ruminants compares well with the level of prevalence reported of cattle of cattle and calls for a concerted government effort for the control of the disease.  相似文献   

19.
Serum samples collected on a single occasion from cattle, sheep and goats at sites in all 10 regions of Ghana were tested for antibodies to Ehrlichia (previously Cowdria) ruminantium, the causative agent of heartwater, by polyclonal competitive ELISA (PC-ELISA). The survey revealed the presence of heartwater-exposed ruminants throughout the country, with local seroprevalence up to 100%. Seronegative, and therefore presumably susceptible, animals were also present in all regions, in some areas in numbers high enough to indicate local endemic instability. Overall seroprevalences in cattle, sheep and goats were 61, 51 and 28% respectively, and were generally higher in the northern part of the country and lower in the forest zone. Amongst animals over 1 year old, two thirds of cattle and sheep, and around one third of goats throughout the country had been exposed to E. ruminantium. In the north, seroprevalence in sheep sampled with and without cattle was similar, whereas in the south seroconversion rates in sheep were significantly higher in areas where cattle were present.  相似文献   

20.
OBJECTIVE: To determine the prevalence and characteristics of attaching and effacing Escherichia coli (AEEC) in diarrheic and healthy small ruminants. ANIMALS: 502 lambs and kids with diarrhea and 511 healthy sheep and goats. PROCEDURE: Fecal samples from diarrheic and healthy sheep and goats were screened for the eae gene. In addition, E coli isolates with positive results for the eae gene (E coli eae+) were analyzed for the espB gene, production of verotoxins (VT), and serogroup. RESULTS: A significantly higher prevalence of healthy lambs and kids were infected with AEEC, compared with diarrheic lambs and kids and healthy adult sheep and goats. Some differences in the characteristics of E coli eae strains isolated from diarrheic and healthy animals were detected. Thus, the espB gene was detected more frequently among E coli eae+ strains isolated from healthy animals than in those isolated from diarrheic animals, and VT production was only detected in E coli eae+ strains isolated from healthy lambs and kids. The E coli eae+ isolates belonged to several O serogroups. However, 17 of 40 (42.5%) isolates from diarrheic lambs and only 4 of 168 (2.4%) isolates from healthy sheep belonged to serogroup 026. CONCLUSIONS AND CLINICAL RELEVANCE: Our results suggest that E coli eae+ 026 strains may play a role in diarrheal disease in lambs, whereas E coli eae+ strains that also had VT production and eae+ strains that had positive results for the espB gene did not appear to be associated with diarrhea in small ruminants.  相似文献   

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