Large Numbers Of Livestock Research Articles

Adoption of recommended hand hygiene practices to limit zoonotic disease transmission at agricultural fairs

Rapid transmission and spread of infectious pathogens are enhanced by the agricultural fair environment, where large numbers of livestock and people from numerous backgrounds congregate for several days. The transmission of influenza A virus and zoonotic enteric pathogens to fairgoers is a considerable risk and has occurred several times over the past decade. In an effort to mitigate zoonotic disease transmission in these settings, public health guidelines and recommendations including hand sanitation stations have been implemented. While hand hygiene recommendations to prevent the spread of zoonotic disease are well communicated, it is hypothesized that the adoption of these recommendations by agricultural fairs and fairgoers is low. To test this hypothesis, hand hygiene data collected from 658 agricultural fairs between 2012 and 2019 was analyzed to determine frequency and function of hand sanitation stations at the fairs, as well as utilization of educational signage. In addition, an observational study was performed to calculate the proportion of fairgoers who use hand sanitation stations at the fair. Lastly, samples were taken from working hand sanitation stations present at the exits of livestock barns and tested for the presence of influenza A virus and antimicrobial resistant coliform bacteria. Hand sanitation stations were present at most fairs (77.4 %) as recommended, but only 142 out of 2021 (7.0 %) visitors were observed using the stations. Health risk signage was displayed at more than half of fairs while the proper wash procedure was displayed at less than half. No influenza A virus was detected on any of the hand sanitation stations, however antimicrobial resistant coliform bacteria were recovered from 75.5 % of the sampled hand sanitation stations. Fairs should employ educational material along with functional hand sanitation stations in order to promote hand hygiene at fairs. Stations should be maintained and cleaned often to ensure effectiveness, as hand hygiene continues to be recommended to fairgoers when exiting animal barns to reduce zoonotic disease transmission.

Innovative Design of Dryer in Utilization and Disposal of Livestock and Poultry Manure

With the rapid development of large-scale and intensive livestock and poultry farming, a large number of livestock and poultry manure has been produced. If livestock and poultry manure is directly stacked or improperly disposed of, it will cause extremely serious pollution to the surrounding water, air and soil, and endanger human health. It is an effective method to dispose and utilize livestock and poultry manure properly according to local conditions. However, because of the large water content of livestock and poultry manure, most of the water in the manure needs to be removed before resource disposal. Therefore, drying livestock and poultry manure is a necessary link in the resource disposal and utilization of livestock and poultry manure. In view of the shortcoming of high energy consumption, uneven drying and low drying efficiency existing in the existing drying technology equipment for livestock and poultry manure, on the basis of overall design and working principle analysis of the livestock and poultry manure dryer, innovative designs are made in the following aspects: improving the efficiency of material transportation from the sloping spiral feeding device; at the bottom of the feed box, seepage holes are equipped with, which can preliminarily filter and separate the moisture in livestock and poultry manure; the conveyor belt in the drying oven adopts three-step jump conveyor mode to realize the rolling conveyor drying of livestock and poultry manure. These innovative designs can improve the transportation efficiency, drying uniformity and drying efficiency of livestock and poultry manure, effectively reduce the moisture content in livestock and poultry manure, reduce the energy consumption of dryer, and effectively realize the resource disposal and utilization of livestock and poultry manure.

Can hyena behaviour provide information on population trends of sympatric carnivores?

Mammalian carnivores are declining worldwide owing to human activities. Behavioural indicators have the potential to help identify population trends and inform conservation actions, although this area of research is understudied. We investigate whether behaviour is linked to abundance in a community of carnivores in the Masai Mara National Reserve, Kenya. Anthropogenic disturbance increased exponentially in parts of the Reserve between 1988 and 2017, mainly owing to daily incursions by large numbers of livestock and tourists. Previous research showed that hyena behaviour changed markedly during this period. Through a series of vignettes, we inquire whether hyena behaviours correlate with changes in abundance of hyenas themselves, or those of other carnivore species in the region. We find that changes in spotted hyena behaviour in disturbed areas, but not in undisturbed areas, can be linked to changes in their demography (vignette 1). We also find that declines in observed lion-hyena interactions, as well as increases in spotted hyena abundance, are probably caused by competitive release of hyenas from declining lion abundance (vignette 2). Finally, we demonstrate that in some cases, hyena behaviour and demography is linked to the density and distribution of sympatric carnivores, and that behavioural changes in hyenas can provide information on shifts within the carnivore community (vignettes 3 and 4). Our vignettes reveal intriguing relationships between behaviour and demography that should be explored in future research. Pairing behavioural studies with more traditional monitoring efforts can yield useful insights regarding population and community trends, and aid wildlife conservation and management. This article is part of the theme issue 'Linking behaviour to dynamics of populations and communities: application of novel approaches in behavioural ecology to conservation'.

Cross-border dissemination of lumpy skin disease: risc analysis for Ukraine

National biosecurity is a system of organizational and technical measures that help protect humans, animals and the environment from potential and actual biological threats. That is why analysis of the main hazardous biological sources for humans and animals has been carried out. The influence of climate change on the animals’ welfare as well as their predisposition to the deferred type tendency is proved. The prevalence of vector diseases of animals, mycoses and mycotoxicoses, which can manifest themselves in the form of such emergencies as outbreaks of exotic diseases, large-scale epizootics, a sharp increase of the incidence of endemic diseases, etc., are of both ecological and biological danger. Contagious vesicular (nodular) dermatitis (Lumpy skin disease, LSD) is caused by the virus belonging to the genus Capripoxvirus, the Poxviridae family and affects mainly cattle and buffaloes. The virus is distributed mainly by means of mechanical carriers (species of Stomoxys spp. and other flies). Global warming on the European continent facilitates the migration of blood-sucking insects that are carriers of vector diseases. As a result, the insects occupy new ecological niches adapting to the new biocenoses. A poorly controlled movement of large numbers of livestock also creates a risk of disease spreading. The World Organization for Animal Health (OIE) has identified LSD as highly dangerous illnesses subject to notification. The focus is made on policies dealing with the control and eradication of contagious nodular dermatitis in case of its detection. The spread of LSD can be prevented through the introduction of biosafety measures at the farm level and the introduction of restrictions on the movement of infection-susceptible animals and goods from the infected territories. Vaccination is the most effective disease control tool in endemic areas. LSD control and elimination policy in case of disease detection includes sanitary slaughter (stamping-out) of infected animals – a complex of antiepizootic measures that carry out by direction of the chief state inspector, including the slaughter of sick and infected animals of the herd, and if necessary, animals of another herd that could lead before the transmission of a pathogenic agent – the pathogen of contagious nodular dermatitis of cattle. All animals, that are susceptible to the disease, whether vaccinated or not, are clogged and their carcasses are destroyed by burning, burial with the guarantee of preventing the spread of infection through carcasses or other products of dead animals. Emergency control of outbreaks envisages the ring vaccination of buffer zones within 25–50 km from infected areas, as well as foundation of temporary or permanent slaughter places in the infected areas. Sufficient herd immunity must be created and maintained within large territories both around the infected area and at the borders with infected countries. Such immunity is achieved when 80% of the herd is covered by vaccination.

Fuzzy risk assessment modelling of wild animal life in Bijar protected area

Bijar protected area (BPA) is suffering from land use change and livestock grazing. Since 1977, the number of main species (Ovis orientalis gmelini) living in BPA has reduced from 2000 to 435. In order to study the wild animal life (WAL) risk of BPA, a Fuzzy model in Geographical information system (GIS) environment and remote sensing was utilized. The seven selected input indices for the model were 'BPA conversion rate', 'Natural resource', 'Population density', 'Population growth rate', 'Social status', ' Security threat', and 'Livelihood status'. BPA conversion rate was obtained based on Landsat 8 Satellite images of 2016 and agricultural area maps of BPA villages. The weight and Fuzzy rules ranges of the sub-indices were created based on an expert opinion survey (questionnaire) developed according to the related literature. Sub-indices were union in vector format in the GIS environment to acquire the main indices and they were overly in raster format based on Fuzzy membership functions to obtain the WAL risk in three levels of high, moderate and low. Results showed that the areas with high risk were (i) agricultural lands, (ii) lands that underwent use change (rangelands to agricultural lands), (iii) areas with a large number of livestock, (iv) areas within the proximity to roads, and (v) areas far from the protected stations. From the results it can be concluded that low level of livelihood, low number of protective stations and weak protective regulations are the main reasons behind increasing WAL risk in BPA.

Epidemiological features of Echinococcus granulosus in Southern Russia

Background: Human Echinococcosis is a widely distributed parasitic infection with formation of permanent endemic foci. Dry and hot climate in the South of Russia, a large number of livestock and dogs maintain current foci of disease. These areas are the habitat of all wild animals - definitive hosts of Echinococcosis (wolf, jackal, fox, raccoon dog and Vulpes corsac). High prevalence of echinococcosis in humans constantly is recorded in Karachay-Cherkessia and Kabardino-Balkaria, Astrakhan and Stavropol Territories. Human morbidity in these areas exceeds the average level in Russian Federation 2 times or even more. However, in the neighboring areas (Ingushetia, Chechnya, Rostov region), with the same conditions for the implementation of the full life cycle of parasite, the incidence of Echinococcosis is missing or significantly below average in Russian Federation. Aim of the study is to determine the reasons of variability in the incidence of Echinococcosis population on the territories with similar climatic and household conditions in southern Russia Methods & Materials: During the period from 2008 to 2016 we performed a retrospective analysis of 92 medical records of patients who were surgically treated for echinococcosis in the Republican hospital in Karachay-Cherkessia and 76 patients, operated on Echinococcosis in Regional hospitals #2 in the Rostov region. Also we analyzed 96 epidemiological survey of Echinococcosis cases in the Karachay-Cherkessia and 52 - in the Rostov region. 6210 blood serum of healthy inhabitants of Rostov and Astrakhan regions, Krasnodar Territory, Adygea and Karachay-Cherkessia has been studied by enzyme immunoassay (ELISA). Results: Analysis of the medical records demonstrated that the number of patients received surgical treatment in hospitals of Rostov region in the period 2008-2016 exceeds the number officially registered. In Karachay-Cherkessia the number of officially reported cases more than number of patients surgery treated for Echinococcosis in the Republican hospital, because patients operated in other territories of southern Russia are also taken into account. The results of sero-epidemiological surveys showed that the percentage of seropositive persons among conditionally healthy population of the Rostov Region two times higher than in Karachay-Cherkessia (1.01% and 2.85% respectively). Conclusion: The real prevalence of Echinococcosis in some territories of southern Russia higher than official statistics.

Exploring the spatio-temporal processes of communal rangeland grabbing in Sudan

The persistent policy of successive Sudanese governments in favouring large-scale agricultural investments at the expense of traditional land use is creating material differences among significant groups of the population. A significant share of this type of investment falls within the territories of the communal rangelands of the country. The aim of this paper is to provide analytical insights of the geographical allocation and the temporal evolution of land grabbing on the expanses of communal land utilized by local inhabitants in Butana area in eastern Sudan. The study relies on multi-temporal Landsat satellite imagery (2000, 2005, 2009, and 2014), ground surveys, and key informant interviews. The results show that large-scale mechanized agriculture (LSMA) in Butana communal rangeland increased incrementally from 2.5% in 2000 to 17.6% in 2014. The starting location of the expansion of LSMA was in surrounding valleys. From the images, it is clear that land grabbing is converting the natural vegetation cover of Butana communal rangeland into spatially fragmented patches. Large-scale farmers (LSFs) involved in the process included wealthy pastoralists who own large numbers of livestock and absentee farmers who rely on hired representatives to manage their agricultural operations. Without a fundamental change in governmental policy, which currently turns a blind eye to the illegal activities of LSFs on communal rangeland, the gloomy scenario of land-based conflict may erupt in the eastern part of the country.

WATER AND HYGIENE IN THE KHARAA RIVER BASIN, MONGOLIA: CURRENT KNOWLEDGE AND RESEARCH NEEDS

The Kharaa River Basin has some of the highest densities of population, agricultural and industrial activities in Mongolia. This puts the naturally limited water resources under pressure in both a quantitative and qualitative perspective. Besides mining, key sources of surface water contamination include large numbers of livestock in riverine floodplains and the discharge of untreated or poorly treated waste waters, both into rivers and by soil infiltration. Since both shallow groundwater and river water are used by people and for livestock, there are at least theoretical risks related to the transmission of water-borne pathogens. Only a very limited number of studies on water and hygiene have so far been conducted in Mongolia, all indicating (potential) risks to water users. However, a lack of current and reliable water microbiology data leads to the need of systematic screening of water hygiene in order to derive conclusions for public health and drinking water management at the local and regional scale.

Assessment of Vaccination Coverage of Sheep and Goat using Retrospective Data in Woreda Raya Alamata

A retrospective study using data of the record of the veterinary clinic of Alamata Woreda with the objective of assessment vaccine coverage in the area was conducted from May to June 2014. The data indicated that there was vaccination program for ovine pasteurellosis, sheep and goat pox, pestides petites ruminits and anthrax. The vaccination coverage in the area was very minimal and did not cover the whole livestock population. This might be the reason for the re-occurrence of the disease in different years. Hence, use of high quality and effective vaccines to cover a large number of livestock is essential for the disease mitigation in the area. Keywords : Anthrax, Pasteurellosis, Pest ides petites ruminits, Pox vaccine, Alamata, Tigray, Ethiopia.

Smart livestock feeding strategies for harvesting triple gain – the desired outcomes in planet, people and profit dimensions: a developing country perspective

Of the total greenhouse gas emission from the livestock sector, 45% relates to feed production and processing. Enteric methane (35%), land-use change (9%) and manure nitrous oxide and manure methane together (9.5%) are the other sources of greenhouse gas emissions, which to a large extent depend on feed types. Inefficient use of feeds reduces profitability. Increasing future feed demand and food-feed-fuel competition have environmental and social impacts. The growth for demand in livestock products comes with social, economic and environmental challenges. This paper argues that the efficient utilisation of feed resources and application of appropriate feeding strategies are vital for strengthening the three conventional pillars of sustainability (environment, social and economic). Towards this end, it identifies and explores a series of promising innovations and practices in feed production and feeding including balanced and phased feeding; increase in the quality and level of use of forages in diets; reduction in use of grains; harvesting forages when nutrient availability per unit of land is maximum; targeted mineral feeding; reduction in feed losses; use of straw-based densified feed blocks; better recycling of human food wastes and human-inedible food components to feed; new business models for production and use of urea-ammoniated straws, urea-molasses blocks, forages and silages in smallholder farms; and use of underutilised locally available feed crops linked with strengthening of seed development and distribution infrastructure. The development of simple tools and on-site assays for correcting nutritional imbalances also offers interesting opportunities. Collection of data on feed availability at the national level, and generation of sound chemical composition and nutritional value data of feeds, are a prerequisite to innovate. The focus of the discussion will be on low-input livestock systems in developing world. A large number of livestock are found in such systems and small improvements can have high global impact. In addition to the technological aspects, policy and institutional building options required to realise large impact are also discussed.

Surface modeling of soil antibiotics

Large numbers of livestock and poultry feces are continuously applied into soils in intensive vegetable cultivation areas, and then some veterinary antibiotics are persistent existed in soils and cause health risk. For the spatial heterogeneity of antibiotic residues, developing a suitable technique to interpolate soil antibiotic residues is still a challenge. In this study, we developed an effective interpolator, high accuracy surface modeling (HASM) combined vegetable types, to predict the spatial patterns of soil antibiotics, using 100 surface soil samples collected from an intensive vegetable cultivation area located in east of China, and the fluoroquinolones (FQs), including ciprofloxacin (CFX), enrofloxacin (EFX) and norfloxacin (NFX), were analyzed as the target antibiotics. The results show that vegetable type is an effective factor to be combined to improve the interpolator performance. HASM achieves less mean absolute errors (MAEs) and root mean square errors (RMSEs) for total FQs (NFX+CFX+EFX), NFX, CFX and EFX than kriging with external drift (KED), stratified kriging (StK), ordinary kriging (OK) and inverse distance weighting (IDW). The MAE of HASM for FQs is 55.1μg/kg, and the MAEs of KED, StK, OK and IDW are 99.0μg/kg, 102.8μg/kg, 106.3μg/kg and 108.7μg/kg, respectively. Further, RMSE simulated by HASM for FQs (CFX, EFX and NFX) are 106.2μg/kg (88.6μg/kg, 20.4μg/kg and 39.2μg/kg), and less 30% (27%, 22% and 36%), 33% (27%, 27% and 43%), 38% (34%, 23% and 41%) and 42% (32%, 35% and 51%) than the ones by KED, StK, OK and IDW, respectively. HASM also provides better maps with more details and more consistent maximum and minimum values of soil antibiotics compared with the measured data. The better performance can be concluded that HASM takes the vegetable type information as global approximate information, and takes local sampling data as its optimum control constraints.

Bird Abundance, Diversity and Habitat Preferences in the Riparian Zone of a Disturbed Wetland Ecosystem – the Kilombero Valley, Tanzania

Wetlands provide important habitats to many bird species but are also under threat from human-caused degradation. The Kilombero Valley Floodplain Ramsar site in Tanzania has been subject to an increasing level of disturbance, but harbors the endemic Kilombero Weaver, Kilombero Cisticola and White-tailed Cisticola, as well as several other species of local, national and global importance. Using point counts over a year, we studied seasonal patterns in bird species richness, diversity and abundance, as related to habitat types in the riparian zone along the Kilombero River. Particular focus was on Important Bird and Biodiversity Area (IBA) ‘trigger’ species. Richness, abundance and diversity were highest in July, just after the wet season, and lowest in March when the water level started rising. The endemic Kilombero Weaver (Ploceus burnieri) was by far the most common species. Reeds and grass-bush habitats had the highest bird diversity throughout, and all three endemic taxa showed a preference for these vegetation types. After decades of increasing human disturbance, Kilombero still qualify as an IBA. Large numbers of livestock have recently been evicted from the area, and this study could serve as a benchmark on how this change will affect bird populations in the future.

Context-, phenotype-, and kin-dependent natal dispersal of barn swallows (Hirundo rustica)

Natal dispersal is a major life-history trait, with important consequences for population dynamics and genetic structure. Successful dispersal depends on a complex blend of decisions at all main stages of the dispersal process: emigration, prospection for a site, and settling. Costs and benefits of such decisions are expected to depend on sex and on the ecological context, on individual physiological state, and on concomitant decisions by relatives, which affect competition with kin and inbreeding. We analyzed natal dispersal propensity (i.e., dispersing or not) and dispersal distance in the semicolonial barn swallow (Hirundo rustica) in relation to context-, phenotype-, and kindependent factors. Females had larger dispersal propensity and distance than males. Dispersal propensity of both sexes was negatively density dependent and was less likely from colonies (farms) with large number of livestock, which is important to barn swallow distribution. Dispersal propensity was larger among males ranking high in the body mass brood hierarchy and smaller among late-hatched females. Dispersal distance was larger for late-hatched males and for females that ranked high in the body mass brood hierarchy. Finally, both dispersal propensity and distance of males increased with the number of male siblings. We, thus, identified several context-, pheno type-, and kin-dependent components of dispersal decisions. Phenotype-dependent effects suggest that decisions of whether to disperse and of dispersal distance are different processes under control of sex-specific traits. Finally, male dispersal behavior suggests that kin selection favors males that reduce the risk of sib–sib mating competition, in a population with male-biased tertiary sex ratio.

Effect of glucose, galactose and lactose on the growth curve of Clostridium perfringens type A

One of the common diseases of cattle and sheep and other animals in the world and Iran, is enterotoxaemia. This disease is dangerous and deadly threat to the livestock facilities because of economic conditions for the bacteria to multiply in large numbers of livestock in a place. In the study, bacteria were isolated in Phosphate Buffered Saline (PBS) culture by ELISA. The Effect of sugars glucose, galactose and lactose on the growth curve ofClostridium perfergenesis type A was measured by spectrophotometry. In 0.2 ml concentration, sugars were not significantly different between control and treatment but in the 0.3 and 0.4 ml concentration, the start of growth stage of sugars can be significantly affected. These sugars can have effect on the start stage of C. perfringens type A. Key words: Clostridium perfringens type A, growth curve, glucose, galactose, lactose.

Livestock Husbandry and Economic-Sustainability of Small Farmers in Peri-Urban Areas: A Case Study from West Gojjam Region, Ethiopia

The study attempts livestock husbandry and sustainability of small farmers in West Gojjam region, Ethiopia where a large number of livestock are reared due to the favorable climatic conditions. The mainstay of the population (those with holding of less than 3 ha) practices mixed crop-livestock farming. It discovers issues of the economic and gender profiles of livestock rearers and their engagement in different operations of livestock husbandry for economic sustainability. Systematic random sampling was applied technique to select 240 households from four micro geographical areas (kebeles) of peri-urban region on the basis of purposive sampling at the distance of 10, 20, 30, 40 km from central business district. The findings describe 51.6% contribution of females in livestock husbandry for barn and cleaning while men performed 71.5% marketing activities. More than 87% agricultural operations were done by men using livestock. The Animal husbandry contributes 60-70% income among the 51.25% households of small farmers. The growing of income by livestock per year was 6.1% during 2001-2011. However, ranching of goats and sheep was remarkable for high value added role (11%) during 2001-11. The study presents recommendations for efficient marketing system, well equipped transportation facilities to improve social-economic sustainability of small farmers.Keywords: work equity, productivity by gender, economic viability and sustainability

Good dog! Using livestock guardian dogs to protect livestock from predators in Australia's extensive grazing systems

Context Wild predators are a serious threat to livestock in Australia. Livestock guardian dogs (LGDs) may be able to reduce or eliminate predation, but their effectiveness in Australian grazing systems has not been systematically evaluated. In particular, little is known about the effectiveness of LGDs in situations where they range freely over large areas in company with large numbers of livestock. Aims We aimed to evaluate the effectiveness of LGDs as currently used in Australia and determine the factors influencing effectiveness, in particular in relation to scale of management. We also documented how LGDs are managed in Australia, evaluated their cost effectiveness, and identified factors that influence the number of dogs required in different property situations. Methods We conducted a telephone survey of 150 livestock producers with LGDs in Australia, including all livestock types and property situations, in all States. Ten producers were visited, of which one is detailed as a case study. Key results Effectiveness was apparently high: 65.7% of respondents reported that predation ceased after obtaining LGDs, and a further 30.2% reported a decrease of predation. When the number of stock per dog exceeds 100, LGDs might not be able to eliminate all predation. Dogs are often kept free-ranging on large properties where wild dogs are the main predator, but are usually restricted in their movements on smaller properties or with smaller predators. The cost of obtaining a LGD is returned within 1–3 years after the dog starts working. The number of dogs required for a property mainly depends on the number of livestock needing protection, and the main type of predator in the area. Conclusions Provided a sufficient number of LGDs are used, they can be as effective in protecting livestock from predators in Australia when ranging freely on large properties with large numbers of livestock as they are in small-scale farming systems. Implications LGDs can provide a cost-effective alternative to conventional predator control methods in Australia’s extensive grazing enterprises, potentially reducing or eliminating the need for other forms of control. LGDs could play a major role in securing the viability of livestock businesses and reconciling people–predator conflict in Australia.

The Prevalence of Antimicrobial-Resistant Escherichia coli in Two Species of Invasive Alien Mammals in Japan

The prevalence of antimicrobial resistance in 128 Escherichia coli isolates was investigated in two species of invasive alien mammals (IAMs): the small Asian mongoose (SAM) and Japanese weasel (JW). The SAM is found on the main island of Okinawa, Japan, where a large number of livestock is available, and the JW is present on a small island, where is isolated from the main island, and have a small number of livestock. We focused on the two IAMs, inhabiting under the different environments, and compared their prevalence of antimicrobial-resistant E. coli. In the comparison of the frequencies of antimicrobial-resistant E. coli isolates between the SAM and JW, JW showed significantly higher prevalence of resistance against three drugs, ampicillin, chlortetracycline and nalidixic acid, compared with SAM's test results (P<0.05). The bla(TEM) gene and the aph1 gene were detected in 35 subjects (91%) of ampicillin-resistant isolates and 6 subjects (100%) of kanamycin-resistant isolates, respectively. The tet (A) gene was detected in 62 subjects (46%) of CTC-resistant isolates, and the tet (B) gene was detected in 25 subjects (8%) of those in IAM. The present results suggest that some IAMs were the carrier of antimicrobial-resistant bacteria and their genes, and the frequencies of these resistances were different between two IAM species.

Influence of livestock on the regeneration of fodder trees along ephemeral rivers of Namibia

Faidherbia albida and Acacia erioloba (Mimosoideae) are important fodder trees for livestock and wildlife along the westward flowing ephemeral rivers of the Namib Desert. Together with other, mainly woody vegetation, F. albida and A. erioloba line these rivers and present a linear oasis in a resource poor environment. For centuries nomadic to semi-nomadic inhabitants seasonally utilised the resources of these ephemeral rivers to survive in the otherwise harsh desert environment. In the past decades, more permanent settlements were established along these rivers, with small stock subsistence farmers making a living from the available resources. Livestock (mainly goats) usually moves freely around, feeding on the available vegetation.This study investigated the influence of free moving animals on the regeneration and recruitment of F. albida and A. erioloba along the Kuiseb ephemeral river. It was found that a large numbers of recently emerged seedlings were removed soon after germination. In addition, tree densities of adult versus juvenile individuals differed in areas with large numbers of livestock. The overall height increase and health of juvenile plants were influenced negatively by browsing livestock. In general, browsing pressure differed spatially and was higher close to the main water channel.

Molecular cloning and expression of epsilon toxin from Clostridium perfringens type D and tests of animal immunization

Epsilon toxin produced by Clostridium perfringens types B and D causes enterotoxemia in sheep, goats and calves. Enterotoxemia can cause acute or superacute disease, with sudden death of the affected animal. It provokes huge economic losses when large numbers of livestock are affected. Therapeutic intervention is challenging, because the disease progresses very rapidly. However, it can be prevented by immunization with specific immunogenic vaccines. We cloned the etx gene, encoding epsilon toxin, into vector pET-11a; recombinant epsilon toxin (rec-epsilon) was expressed in inclusion bodies and was used for animal immunization. Serum protection was evaluated and cross-serum neutralization tests were used to characterize the recombinant toxin. To analyze the potency of the toxin (as an antigen), rabbits were immunized with 50, 100 or 200 microg recombinant toxin, using aluminum hydroxide gel as an adjuvant. Titers of 10, 30 and 40 IU/mL were obtained, respectively. These titers were higher than the minimum level required by the European Pharmacopoeia (5 IU/mL) and by the USA Code of Federal Regulation (2 IU/mL). This rec-epsilon is a good candidate for vaccine production against enterotoxemia caused by epsilon toxin of C. perfringens type D.

A survey of Crimean-Congo haemorrhagic fever in livestock and ticks in Ardabil Province, Iran during 2004–2005

Crimean-Congo haemorrhagic fever (CCHF) is a viral haemorrhagic fever caused by the CCHF virus. It is mainly transmitted to humans and animals by ticks. In recent y, large numbers of livestock have been transported across the border areas of Ardabil Province resulting in an outbreak of CCHF in the adjacent districts. A comprehensive study was carried out to assess the epidemiological aspects of the disease in this province. In the study area, 130 ticks were collected from randomly selected villages and classified into 9 species of hard tick and 2 species of soft tick. All ticks were analyzed for the presence of CCHF virus genome using gel-based and real-time reverse transcriptase polymerase chain reactions (RT-PCR). The results showed CCHF infection in almost 28% of ticks collectively. Also, of 56 livestock sera, around 39% were IgG-positive. The presence of anti-CCHF virus IgG antibodies and the CCHF virus genome in ticks points to a great hidden threat of an outbreak in these districts. Those in high-risk professions in this province should be informed and trained on the risk of CCHF with urgency.