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1.
We explored observed risk factors and drivers of infection possibly associated with African swine fever (ASF) epidemiology in Uganda. Representative sub-populations of pig farms and statistics were used in a case-control model. Indiscriminate disposal of pig viscera and waste materials after slaughter, including on open refuse dumps, farm-gate buyers collecting pigs and pig products from within a farm, and retention of survivor pigs were plausible risk factors. Wire mesh-protected windows in pig houses were found to be protective against ASF infection. Sighting engorged ticks on pigs, the presence of a lock for each pig pen and/or a gate at the farm entrance were significantly associated with infection/non-infection; possible explanations were offered. Strict adherence to planned within-farm and community-based biosecurity, and avoidance of identified risk factors is recommended to reduce infection. Training for small-scale and emerging farmers should involve multidimensional and multidisciplinary approaches to reduce human-related risky behaviours driving infection.  相似文献   

2.
The straight white spines of African Acacia species are conspicuous, rather than being brown and cryptic as in other species. In comparison with species with brown spines, Acacia spines are composed of less dense material. I suggest that by the Acacia spines being readily apparent, browsers can avoid biting them. This avoidance facilitates the trade-off of decreased sturdiness for increased apparency.  相似文献   

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《African Zoology》2013,48(2):412-417
The name Turritella declivis, as described by Adams and Reeve in the ‘The Zoology of the Voyage of HMS Samarang’ (Adams & Reeve 1848-1850), is currently used for two distinct species of turritellid gastropod, one inhabiting the Agulhas Bank off South Africa and the other occurring off the Australian coast. Examination of the type material clearly shows that the name is referable to the southern African species. The Australian species must henceforth be known as Turritella captiva Hedley, 1987, a name previously regarded as a junior synonym of T. declivis. The original type locality ‘China Seas’ is erroneous, as was often the case with material collected during the voyage of the Samarang. It is emended to be the Agulhas Bank, over much of which T. declivis is common and may, in places, be hugely abundant, forming Turritella-dominated benthic communities. Such communities have been recorded in other parts of the world and are frequently associated with seasonal upwelling events, but have not previously been documented off South Africa.  相似文献   

5.
One hundred and fifty West African Dwarf (WAD) kids were tested at the National Goats Breeding Station to determine the effects of some neonatal factors on their vigour levels within the first 24 h post-partum. The kids were also tested to establish the relationship between maternal weight, rectal temperature, times of first standing and sucking, sucking period and vigour. The distance covered (in meters) by a kid towards its mother during a 5-min test period was considered as vigour trait. Vigour levels increased significantly (p?<?0.05) with increasing age within the first 24 h post-partum. Kids born to second parity mothers had higher (p?<?0.05) vigour than those born to first parity mothers. Similarly, high birth weight kids had higher (p?<?0.05) vigour levels than low birth weight kids. Weak positive and negative correlations (p?<?0.05), respectively, were found between vigour and rectal temperature, and vigour and the time of first successfully standing. However, there was moderate positive correlation (p?<?0.01) between vigour and sucking period. The time it took for the newborn kid to stand up for the first time also correlated weakly and negatively (p?<?0.01) with the duration of sucking by the newborn within the first 5 min of accessing the teat. Vigour within the first 24 h post-partum in WAD kids increased with increasing age, parity and birth weight and might be responsible for the earlier and longer sucking time and periods, respectively, in high birth weight kids and those dropped by multiparous does.  相似文献   

6.
Trypanosomosis is a serious threat to both man and animals mostly in Africa. Although the first pathogenic trypanosome was discovered over a hundred years ago, there is still no prospect for effective control or eradication of the disease through the development and use of vaccines because of the phenomenon of antigenic variation. Control continues to rely heavily on chemotherapy and vector control strategies. This therapy and prophylaxis depends on the use of drugs which, apart from having been developed over 5 decades ago, suffer from such limitations as toxicity and with their continued use, drug resistance. Resistance to currently used drugs is a serious problem in most fields of anti-microbial chemotherapy, particularly in the case of trypanosomosis where resistance and cross-resistance in animals and man have been developing rapidly. The frequently and widely reported decreasing efficiency of available trypanocides, difficulties of sustaining tsetse control and little hope that a conventional, anti-trypanosome vaccine will be produced in the near future, increase the imperative need for new drugs and alternative effective ways for the control of trypanosomosis. This review examines aspects of drug resistance in pathogenic trypanosomes, measures to minimise it, areas of future research in new drug targets and alternative control strategies. Based on these, it is our opinion that for now the management and control of trypanosomosis will continue to depend on proper usage of the few available trypanocides, especially strategic deployment of the sanative drugs in order to reduce the development of drug resistance, in addition to the continued use of environmentally friendly vector control programmes such tsetse trapping.  相似文献   

7.
A community-based intervention combining health education (HE) and treatment of pigs for control of porcine cysticercosis (PC), gastrointestinal (GI) helminths, African swine fever (ASF) and external parasites was tested involving six villages of resource-poor smallholder pig farmers. Farmers and pigs of six rural villages were randomly allocated into group 1 (HE), which served as controls, and group 2 (HE?+?OFZ) pigs received a single oral dose of 30 mg/kg OFZ. Farmers were trained in pig health, housing and feeding. The proportion of farmers with confined pigs, the adoption rate of the introduced pig pen, the sero-prevalence of PC and ASF, the prevalence and intensity of GI nematodes and the prevalence of ectoparasites were measured at 9, 15 and 24 months after initiation and compared to a baseline survey to seek the effectiveness of the interventions. There was no clear effect of the intervention on the sero-prevalence of PC, but analysis of the rate of change in prevalence between the two groups showed significant effect with the rate of change to lower prevalence in the HE?+?OFZ group compared to the HE group. Although HE managed to improve the farmer’s knowledge in the control and prevention of ASF and ectoparasites, there was no significant reduction in the sero-prevalence of ASF and the prevalence of ectoparasites throughout the two-year period. The reported ineffectiveness of the intervention in this study suggested that more research is needed to develop more effective methods for controlling PC, ASF and pig parasites.  相似文献   

8.
Investigations to identify the causes of high mortalities in cattle in the agropastoral zone (ZAP) of Yalé started in March 1993. African animal trypanosomosis (AAT) was found to be the major constraint, with incidence rates exceeding 30%, justifying a tsetse control programme, which started in March/April 1994. The treatment of all cattle at bimonthly intervals with deltamethrin 1% pour on and the display of 1500 insecticide impregnated targets during the 6 months of the dry season each year helped to reduce the tsetse populations (Glossina tachinoides and G. morsitans submorsitans) by more than 90%. In less than 7 months, the incidence of AAT dropped below 5% and remained there throughout the intervention until June 1996, in spite of an increase to 3 months in the interval between the treatments. Mean PCV values increased significantly from 26.5–30.9%, before, to 30.7–36.3% during the intervention. The improvement in the overall health resulted in a resumption in fertility and milk production, allowing the sale of dairy products in Léo, thus creating a gross income of about $US3/day for the Fulani women.  相似文献   

9.
The accurate estimation of livestock weights is important for many aspects of livestock management including nutrition, production and appropriate dosing of pharmaceuticals. Subtherapeutic dosing has been shown to accelerate pathogen resistance which can have subsequent widespread impacts. There are a number of published models for the prediction of live weight from morphometric measurements of cattle, but many of these models use measurements difficult to gather and include complicated age, size and gender stratification. In this paper, we use data from the Infectious Diseases of East Africa calf cohort study and additional data collected at local markets in western Kenya to develop a simple model based on heart girth circumference to predict live weight of east African shorthorn zebu (SHZ) cattle. SHZ cattle are widespread throughout eastern and southern Africa and are economically important multipurpose animals. We demonstrate model accuracy by splitting the data into training and validation subsets and comparing fitted and predicted values. The final model is weight0.262?=?0.95?+?0.022 × girth which has an R 2 value of 0.98 and 95 % prediction intervals that fall within the ±20 % body weight error band regarded as acceptable when dosing livestock. This model provides a highly reliable and accurate method for predicting weights of SHZ cattle using a single heart girth measurement which can be easily obtained with a tape measure in the field setting.  相似文献   

10.
African horsesickness (AHS) is an infectious but noncontagious viral disease affecting all species of Equidae. The recall immune response of AHSV na?ve horses immunised with an attenuated African horsesickness virus serotype 4 (AHSV4) was characterised using immune assays including ELISPOT, real-time PCR (qPCR) and flow cytometry. The recall immune response detected in PBMC isolated from three inoculated horses showed an upregulation of circulating B lymphocytes that correlated with elevated IL-4 mRNA expression indicative of humoral immunity, but reduced frequency of CD4? cells. In addition to the expected antibody response, an increase in CD8? cells was also detected. Although these CD8? cells may be CTL, the role of these cells in immunity against AHSV still has to be determined.  相似文献   

11.
Holistic Planned Grazing? (HPG) is purported to have positive long-term effects on rangelands, enhancing ecosystem services. Given comparable environmental templates, but different management regimes, vegetation monitoring and landscape function analysis showed the Africa Center for Holistic Management (ACHM) at Dimbangombe had a significantly higher rangeland condition (composition, cover, standing crop and soil health) than adjacent Sizinda (SCR) and Monde (MCR) communal rangelands. Overall grazer density on ACHM is 42% higher than that of SCR (no data for MCR). Finer-scale satellite collar data for ACHM yielded a calculated stocking rate of 0,55 LSU ha-1 y-1 or 24 590 kg km-2, which constitutes high-density grazing. An energy flow estimate shows that the grazing resource would, on average, not be limiting for livestock on ACHM but limiting on SCR. HPG may include an element where kraals are inserted into degraded rangelands for a short period. Overall, ACHM shows stable perennial composition with smaller tufts significantly closer together. A similar result was visible in SCR where maize yields were visibly higher on kraaled areas than on adjacent untreated fields. HPG yields positive long-term effects on ecosystem services (soils and vegetation) and points to the HPG approach enhancing the sustainability of livestock and wildlife in this environment.  相似文献   

12.
The Food and Agricultural Organization (FAO) defined transboundary animal diseases (TADs) as those that are of significant economic, trade, and food security importance for a considerable number of countries. TADs can easily spread to other countries, reach epidemic proportions, and where control, management, or exclusion is required cooperation between several countries. The North African countries are vulnerable to several TADs by virtue of its geographical location, its borders with the Sahel region, and peculiar control constraints on the budgets of the national veterinary services of each country and on the livelihoods of livestock owners across the region. In a narrative approach, we comprehensively described the epidemiology of TADs in North African countries, eradication constraints and control measures adopted to conclude with a proposition of a regional control strategy. Our review uncovered foot-and-mouth disease, peste des petites ruminants, bluetongue, sheep/goats pox, brucellosis, West Nile and Rift Valley fever, as the major TADs in this region, while the major constraints identified were illegal animal movement, communal clashes, unreported outbreaks, poor vaccination coverage, and other factors peculiar to each etiology. Therefore, the establishment of early warning systems and proper implementation of control measures at regional level are highly recommended to the relevant stakeholders involved in TADs control in the region.  相似文献   

13.
ObjectiveTo compare induction times and physiological effects of etorphine–azaperone with etorphine–midazolam immobilization in African buffaloes.Study designRandomized crossover study.AnimalsA group of 10 adult buffalo bulls (mean body weight 353 kg).MethodsEtorphine–azaperone (treatment EA; 0.015 and 0.15 mg kg–1, respectively) and etorphine–midazolam (treatment EM; 0.015 and 0.15 mg kg–1, respectively) were administered once to buffaloes, 1 week apart. Once in sternal recumbency, buffaloes were instrumented and physiological variables recorded at 5 minute intervals, from 5 minutes to 20 minutes. Naltrexone (20 mg mg–1 etorphine dose) was administered intravenously at 40 minutes. Induction (dart placement to recumbency) and recovery (naltrexone administration to standing) times were recorded. Arterial blood samples were analysed at 5 and 20 minutes. Physiological data were compared between treatments using a general linear mixed model and reported as mean ± standard deviation. Time data were compared using Mann-Whitney U test and reported as median (interquartile range) with p ≤ 0.05.ResultsActual drug doses administered for etorphine, azaperone and midazolam were 0.015 ± 0.001, 0.15 ± 0.01 and 0.16 ± 0.02 mg kg–1, respectively. Induction time for treatment EA was 3.3 (3.6) minutes and not different from 3.2 (3.2) minutes for treatment EM. The overall mean arterial blood pressure was significantly lower for treatment EA (102 ± 25 mmHg) than that for treatment EM (163 ± 18 mmHg) (p < 0.001). The PaO2 for treatment EA (37 ± 12 mmHg; 5.0 ± 1.6 kPa) was not different from that for treatment EM (43 ± 8 mmHg; 5.8 ± 1.1 kPa). Recovery time was 0.8 (0.6) minutes for treatment EA and did not differ from 1.1 (0.6) minutes for treatment EM.Conclusions and clinical relevanceTreatment EA was as effective as treatment EM for immobilization in this study. However, systemic arterial hypertension was a concern with treatment EM, and both combinations produced clinically relevant hypoxaemia. Supplemental oxygen administration is recommended with both drug combinations.  相似文献   

14.
The relations between woody and herbaceous plants in southern African savannas are reviewed in the context of pastoral use. Current knowledge is summarized, important gaps are indicated and research priorities are suggested. Although all savannas consist of a grass and a woody component, the physical determinants, biological interactions and individual species properties are unique to each spatial and temporal situation. In addition, past management has resulted in different kinds and degrees of modification. Primary and secondary determinants are discussed in terms of how they influence the structure and productivity of savanna communities. More than one outcome is possible to any competitive interaction owing to the modification of the effects of determinants by changing weather sequences, asymmetrical competition and biological interactions. This contrasts sharply with the conventional rangeland succession model. Relations between woody and herbaceous plants are often discontinuous because of the dynamic interactions between determinants, plants and herbivory. There is an apparent discrepancy between the convex and concave response of grass productivity to increasing woody biomass. It is hypothesized that a single discontinuous function explains this apparent discrepancy. This unifying theorem accounts for the modifications due to changes in levels of determinants and different species mixes within and between sites. With a few notable exceptions, research in southern Africa has been of an ad hoc, empirical and limited nature. It has not aimed at achieving an understanding and a predictive capability beyond the site and circumstances of individual trials themselves. A case is made for a systems‐orientated research approach, so that site and situation‐specific problems can be solved to fulfil management objectives.  相似文献   

15.
Artemisia herbaalba Asso (known in Arabic as Shih) is an evergreen aromatic shrub endemic in North African rangelands with high pastoral and medicinal relevance. The present work was designed to determine the effect of four soluble salts (NaCl, Na2SO4, MgCl2, and CaCl2) on germination of A. herbaalba seeds. Four concentrations (0, 50, 10, and 150 mM) of each salt were used to test the influence of salinities on germination percentage (GP), rate of germination (RG), and germination tolerance index (GTI %). The experiment was conducted in a controlled incubator with a 12h–photoperiod under 15°C dark/25°C light. The results showed that both GP and (RG) decreased significantly with salinity, and the highest GP was observed in the distilled water control (~ 80%). The germination tolerance index (GTI %) revealed that A. herba–alba seeds were more tolerant to CaCl2 than other soluble salts. Comparatively, at high salt concentrations, MgCl2 and Na2SO4 were generally the most toxic salts followed by NaCl and CaCl2. The germination of A. herba–alba over a wide range of soluble salts suggests that this species can establish in salt-degraded soils. Therefore, this species appears a promising candidate for the rehabilitation of rangeland with saline soils.  相似文献   

16.
Summary

The fertility of ten West African Dwarf goats in which oestrus was induced with PGF2α was comparable to that of the five West African Dwarf goats in the control group. Performance indices as determined by duration of oestrus and length of gestation were not affected. Similarly the birth weight of kids was not significantly influenced. However, treated goats were superior to controls when the interval from commencement of experiment to oestrus is considered, although there was no difference between the two treated groups of goats (5 mg vs 10 mg PGF2α).

Results showed that PGF2α could be an important tool in oestrus synchronization and thus in control of the reproductive performance of the West African Dwarf goats under humid lowland tropical environmental conditions.  相似文献   

17.

Objective

The combination of butorphanol, azaperone and medetomidine (BAM) with subsequent antagonism by naltrexone–yohimbine or naltrexone–atipamezole was evaluated for reversible immobilization of captive African lions (Panthea leo).

Study design

Prospective, clinical trial.

Animals

Twenty lions, 11 males and nine females, weighing 38–284 kg were immobilized in South Africa.

Methods

The BAM volume dose rate administered was 0.005–0.008 mL kg?1 (0.6 mL 100 kg?1). Physiologic variables were recorded every 5 minutes. Four arterial blood samples were collected from all animals at 20, 30, 40 and 50 minutes after immobilization for analysis of blood-gases and acid-base status.

Results

The actual doses administered were as follows: butorphanol, 0.18 ± 0.03 mg kg?1; azaperone, 0.07 ± 0.01 mg kg?1; and medetomidine, 0.07 ± 0.01 mg kg?1. The inductions were calm and smooth, and induction time ranged from 4 to 10 minutes (7 ± 2 minutes). The amount of time needed to work with each lion was 70 minutes, and no additional drug doses were needed. Heart rate (40 ± 8 beats minute?1) and respiratory frequency (15 ± 4 breaths minute?1) were stable throughout immobilization. The mean arterial blood pressure of all animals was stable but elevated (142 ± 16 mmHg). The rectal temperature slightly increased over time but remained within acceptable range. The recovery time was significantly shorter when using naltrexone and atipamezole (9 ± 1 minutes) compared to using naltrexone and yohimbine (22 ± 7 minutes).

Conclusion and clinical relevance

The BAM combination proved to be reliable for general veterinary anaesthesia in lions. During anaesthesia, minor veterinary procedures such a blood collection, intubation, vaccination and collaring could safely be performed with no additional dosing required.  相似文献   

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采用混合选择法,育成抗寒、抗病、种子产量高的老芒麦新品种康巴老芒麦。其牧草青绿期长、抗寒、耐旱、抗病、抗倒伏,种子成熟期集中。试验通过品种的育种过程、特征、特性和生产性能。其品种干物质较对照提高15%,种子产量高于对照川草2号品种20%,适应川西北高寒牧区及类似地区种植,是建立人工草地、改良天然草地和生态建设的优良牧草。  相似文献   

20.
内蒙古马业协会一匹新锡林郭勒马(太阳花马)因外力导致臀部大面积血肿,由于受伤面积大导致血肿不能吸收,进而液化周围皮下组织形成囊状[1]。穿刺抽取囊内液体,可见液体呈淡红色并伴有组织碎片。马匹体温及精神正常,无跛行,按压局部反应敏感。内部渗出液不断增多,皮下囊区面积不断下延增大。为防止室间隔综合征出现,计划实施外科穿刺放液并进行留置管冲洗,治疗20 d后痊愈。现将此病例分享给广大兽医,供参考。  相似文献   

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