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1.
A national bovine serological survey was conducted to confirm that the prevalence of brucellosis, bluetongue, and anaplasmosis does not exceed 0.02% (95% confidence) in live cattle in Canada. Sampling consisted of a systematic random sample of 15 482 adult cattle slaughtered in federally inspected abattoirs, stratified by province. Samples were tested to detect antibodies for brucellosis, bluetongue, and anaplasmosis. All samples were negative for brucellosis. Three samples were seroreactors to bluetongue, 2 of which originated from the Okanagan Valley in British Columbia and 1 from Ontario, which after follow-up, was considered an atypical result. A total of 244 samples were seroreactors to Anaplasma and follow-up identified infection in Saskatchewan, Manitoba, and Quebec. In conclusion, the Canadian cattle population remains free of brucellosis and free of bluetongue outside the Okanagan Valley. Canada is no longer free of anaplasmosis and will be unable to claim freedom until eradication measures are completed.  相似文献   

2.
This review article explores past, present and possible future drivers of change in Karoo social-ecological systems. Biogeographically, the Karoo comprises the arid Succulent Karoo and Nama-Karoo biomes covering significant portions of the Northern Cape, Eastern Cape and Western Cape provinces and a smaller part of the Free State. Despite the Karoo’s specific environment and spatial importance nationally (covering some 30% of South Africa), no government structures address its needs holistically. Today it is a politically and economically marginalised region; perceptions of it as a desert easily morph into perceptions of it as deserted and ripe for exploitation for the benefit of external constituencies, whether in the name of astronomy, shale-gas and uranium mining or renewable energy. To manage the Karoo better for present and future generations, it is clearly desirable for social and natural scientists to work collaboratively, yet there is relatively little interdisciplinary work to date. Against this background this review article provides an overview of social and ecological changes historically and in the present, and offers some cautious reflections concerning climate change, changing land use and governance as key drivers affecting trajectories of change into the future.  相似文献   

3.
Beef traders’ and consumers’ perceptions on the development of a natural pasture-fed beef (NPB) brand by smallholder cattle producers were investigated. In total, 18 meat traders (five abattoirs and 13 beef retailers) and 155 beef consumers were interviewed using structured questionnaires. All meat traders had the potential but were not willing to support the development of a NPB brand citing smallholder farmers’ limited ability to supply sufficient volumes of high-quality cattle. Consumers (81%) were prepared to purchase NPB upon availability on the market but were not willing (80%) to pay a brand premium. Logistic regression model results showed that consumers’ willingness to buy NPB and pay a premium were influenced (P < 0.05) by gender, household size, income source, meat preference, meat consumption frequency, money spent on beef, frequency of beef purchases and consumption. Overall, beef traders and consumers held positive impressions regarding the development of a NPB brand by smallholder cattle producers but were not willing to support its development. Positive impressions held by value chain partners on the development of a NPB brand provide a basis for advancing development of a NPB brand. Initial efforts should enhance farmers’ capacity to supply sufficient volumes of high-quality cattle.  相似文献   

4.
A cross-sectional study was conducted between January 2007 and February 2008 to estimate seroprevalence of brucellosis and identify risk factors associated with Brucella infections in commercial cattle in three districts of Lusaka province (Chongwe, Luangwa, and Kafue; n = 849) and in one rural district from the Central province (n = 48). A total of 897 serum samples were randomly collected from 55 farms along with animal-level data such as sex, age, and parity. Sera were screened for presence of anti-Brucella antibodies using the Rose Bengal test, and positive samples were confirmed using competitive enzyme-linked immunosorbent assay. At the animal level, seroprevalence was estimated at 7.9% (95% CI = 4.4–11.4%) in the Lusaka province and 18.7% (95% CI = 7.5–29.9%) for Chibombo district. Brucellosis seroprevalence varied according to district, with Chongwe district recording the highest compared to other districts. Seroprevalence also varied according to sex with bulls (n = 96) having higher seroprevalence (12.5%; 95% CI = 3.8–21.1%) compared to females (8.1%; 95% CI = 4.6–11.6). Similarly, seroprevalence varied according to age groups, with the age category 1–4 years recording the highest (10.7%). The study recorded relatively low Brucella seroprevalence in commercial farms in Lusaka, compared to the traditional small-scale farms. We suggest that testing and stamping out of infected animals is likely to improve the situation and significantly reduce the public health risk associated with Brucella infections in animals.  相似文献   

5.
Leptospirosis is an endemic disease in Latin America, caused by pathogenic bacteria of the genus Leptospira. It is considered one of the main causes responsible for the negative economic impact on global livestock by causing reproductive problems. The research aimed to determine the prevalence of leptospirosis in cattle, sheep, and goats at consorted rearing in the micro-region of Teresina, Piauí state, northeastern Brazil, as well as to identify prevalent serovars and risk factors associated with seroprevalence. Serum samples were analyzed in 336 sheep, 292 goats, and 253 cattle using microscopic agglutination test (MAT). Overall, 378 samples were positive to MAT, with seroprevalence of 42.9%. The prevalences in cattle, sheep, and goats were 50.5, 40.5, and 34.6%, respectively. All herds presented at least one seropositive animal; the Hardjo/Wolffi serovar association was the most common in cattle and Icterohaemorrhagiae in goats and sheep. Beef production (OR?=?4.9), cattle herd over 35 animals (OR?=?4.0), feeding on pasture (OR?=?6.4), weir and/or stream as water source (OR?=?2.1), and no veterinary services (OR?=?2.9) were risk factors for cattle infection. For sheep, intensive management system (OR?=?5.3), suspended slatted facilities (OR?=?2.2), more than 20 sheep in reproductive age (OR?=?1.9), and absence of deworming (OR?=?3.5) were the risk factors, while for goats, the identified risk factors were sheep herd over 52 animals (OR?=?1.9) and no veterinary services (OR?=?1.8). We conclude that the infection was spreading in consorted herds in this region. Thus, it would be interesting and important to conduct educative activities to farmers on the economic impacts of this disease and the need of preventive and control strategies mainly focused on sanitary measures and animal handling.  相似文献   

6.
Linear structures include fences, roads, railways, canalised water ways and power lines, all man-made. Fencing as a way of managing livestock began in the late 1800s, and by the early twentieth century was almost fully implemented throughout the Karoo sensu lato. The advent of these fences, and now in many instances, ‘game proof’ (~2 m high) and electric fences have impacted native flora and fauna in various ways. Roads influence the quality and quantity of vegetation along corridors throughout the Karoo, with impacts on wildlife through increased mortality, but also provide foraging opportunities. Road-side structures, such as transmission poles, offer nest sites and perches in otherwise treeless landscapes, benefiting certain avifauna. Railway lines create similar corridors, carrying ungrazed vegetation along them. Their associated structures – culverts and (historically) steel frame bridges – provide nest sites for birds and some mammals. Transmission cables and pylons along power lines have mixed benefits to conservation, providing bird nest and perch sites, but can also cause bird mortalities. Unquestionably, these linear structures have had marked effects on the biota of the Karoo, through their effects on wildlife and livestock movement and mortality, plant demography and the spread of native and alien species.  相似文献   

7.
Haemonchosis is considered to be the most economically important gastrointestinal disease of small ruminants in the tropics and subtropics. However, chemical anthelmintics, which were the mainstay of control, have been compromised by a high prevalence of resistance worldwide. Copper oxide wire particles (COWP) have been shown to have anthelmintic effects, but few studies have examined their use under field conditions. The use of COWP was therefore evaluated as a tactical anthelmintic treatment in indigenous goats raised under communal farming conditions in Bergville, KwaZulu-Natal Province, South Africa. At the beginning of the summer rainfall season (October 2007), the faecal egg counts of 172 female goats belonging to 15 farmers were determined and this sampling continued every four weeks until the second week of January 2008. The goats within each of the 15 herds were ranked according to their faecal egg counts for this week. The goats were sequentially paired off within each ranking starting with those goats with the highest counts. One goat from each pair was randomly allocated to a treated or control group. Two weeks later, a 4 g COWP bolus was randomly administered to each goat in the treated group. Faecal egg counts were carried out on the goats two weeks following treatment, and the sampling of the goats then proceeded every four weeks until October 2008. Except for the six-week period prior to the administration of the COWP, the goats were examined according to the FAMACHA© system and symptomatically treated with 12 mg/kg levamisole when anaemic. The percentage reduction in faecal egg count due to the COWP treatment was 89.0%. Mean pre- and post-treatment faecal egg counts for the COWP-treated group (n = 73) were 2347 eggs per gram of faeces (epg) and 264 epg, respectively. The corresponding values for the untreated controls (n = 66) were 2652 epg and 2709 epg. The prevalence of Haemonchus spp. larvae in pre- and post-treatment faecal cultures was 72% and 46%, respectively. Symptomatic anthelmintic treatments in combination with mid-summer tactical treatments with COWP appear to be useful strategies for the control of Haemonchus contortus in indigenous goats in this farming system and this approach could have application in other similar agro-ecological zones.  相似文献   

8.
9.
Brucellosis in cattle is a zoonosis mainly caused by Brucella abortus. In Kenya, the disease is widespread, but its prevalence is largely unknown. The objective of this study was to investigate incidence rates of brucellosis and farmers’ knowledge on the disease in Kahuro district, Murang’a County. In this study, 150 pooled milk samples were collected from 75 milk collection centers and tested. Subsequently, 230 milk samples were collected from farmers in 16 collection centers in Wangu and Mugoiri divisions whose pooled samples gave positive results. Five cow owners in each of the 16 collection centers were interviewed using a questionnaire to assess their knowledge levels. Wangu division had the highest incidence rate 19% with positive samples observed from 14 collection centers. Mugoiri division recorded 3% with two collection centers having positive samples, while Murarandia had none. All respondents with no formal education were unaware of the causative agent of brucellosis. There was a significant difference in incidence between Mugoiri and Wangu divisions (p < 0.05). Knowledge levels were high in the young and educated farmers compared to the old and uneducated. Frequent screening for brucellosis to identify infected animals should be initiated thus prevent transmission to other animals and humans.  相似文献   

10.
The success of different rehabilitation treatments following surface mining on the arid west coast of South Africa was assessed. Treatments consisting of one or a combination of topsoil addition, plant translocation and seeding were applied to experimental rehabilitation sites in 2001, while the treatment of another site in 2008 combined all three techniques. Vegetation and species cover, species richness, diversity and evenness, and grazing capacity of rehabilitation sites were sampled during winter 2009 and summer 2010, and compared with a reference site. All rehabilitated sites achieved the objective to attain a minimum grazing capacity of 20 ha per small stock unit. Rehabilitation trials were successful in establishing a vegetation cover, but were unable to return species richness and diversity to reference levels and did not resemble the reference site in species composition. Common species in reference sites were absent or only occurred in low numbers. No treatment outperformed the others and further experimentation is needed to determine the most suitable combination. It is recommended that rehabilitation should be done in multiple stages in future to improve seedling survival and to return species that are unable to establish in the adverse conditions present at the onset of rehabilitation.  相似文献   

11.
Very few soil seedbank studies have been conducted in South Africa, especially in arid rangelands. Insight into the soil seedbank could therefore improve assessment of rangeland dynamics and enhance rehabilitation efforts. This study aimed to characterise the soil seedbanks in various vegetation types of the Tankwa Karoo National Park, an arid environment in South Africa. At 43 sites soil was sampled twice at the end of spring and the end of autumn, and the composition and structure of aboveground vegetation were described at the peak growth period in spring. Seeds were isolated from the soil samples by means of flotation in a salt solution, seedbank species composition was obtained by seedling germination, and the vegetation was investigated using a line-point survey method. Overall seed density was 8 034 seeds m?2 of which 55% was viable, and the common life-forms were therophytes and chamaephytes. Species richness and diversity were lower in the seedbank compared with those of the vegetation, and the two vegetation spheres were 25% similar. While seedbank composition suggested poor veld condition, there was enough seed density and viability for future regeneration and rehabilitation initiatives. However, this may be impeded by the absence of many perennial species in the soil seedbank.  相似文献   

12.
Objectives : The objective of this study was to evaluate the surgical times for removal of ovaries, and the frequency of intra‐operative complications with two different instruments used for canine laparoscopic ovariectomy. Methods : A randomised prospective clinical study. Laparoscopic ovariectomy was performed under general anaesthesia on 10 healthy female dogs admitted for elective ovariectomy. Each ovary was randomly assigned to removal by use of either a SonoSurg? ultrasonic surgical device (Olympus), or a LigaSure? vessel‐sealing system (Valleylab/Covidien). Surgical time for removal of each ovary was measured and the frequency of intra‐operative complications was recorded. A follow‐up was made by interview with the owners, 2·5 years after surgery. Results : The two techniques did not statistically differ with regard to surgical time, or frequency of complications. All owners were very satisfied with the procedure. Clinical Relevance : Both the SonoSurg? and the LigaSure? devices appear to be effective, safe and easy to use when performing laparoscopic ovariectomy in dogs.  相似文献   

13.
OBJECTIVE: The ocular microflora in dogs has not been established in north-east Brazil. Thus, the main aim of this research was to determine the bacterial microorganisms in the conjunctival sac of clinically normal dogs and dogs with ulcerative keratitis in Fortaleza, Ceará, Brazil. ANIMALS STUDIED: This study included 60 healthy dogs, 15 dogs with unilateral corneal ulcer, and three dogs with bilateral corneal ulcers. Procedure Samples were taken by a calibrated platinum loop (1 microL) placed directly onto the conjunctival sac and on sterile blood agar. The clinical specimens were incubated at 37 degrees C in an atmosphere of 5% CO2 for 48 h. RESULTS: Of the 120 samples from healthy dogs, only 47 (39%) had positive culture for bacteria, while all of the specimens from eyes with corneal ulcer were positive for bacterial growth. The group of dogs with corneal ulcer had a higher (P < 0.05) number of colony-forming units (CFU) per plate than the group of healthy animals. Of the 59 isolates from healthy eyes, only nine (15.3%) had more than 50 CFU per plate, while in the group of dogs with corneal ulcer, 23 (62.2%) of the 37 isolates presented more than 50 CFU per plate. In both groups Gram-positive bacteria (86.5%) predominated over Gram-negative (13.5%). Staphylococcus spp. was the most frequently isolated genus and S. intermedius predominated in both groups. CONCLUSION: The results of our study are directly applicable to initiate rational, preventive and therapeutic measures with greater accuracy in dogs with corneal ulcer.  相似文献   

14.
To evaluate the prevalence and possible risk factors for brucellosis caused by Brucella abortus in water buffaloes in the state of Pará, Brazil, 3,917 female buffalo serum samples from pregnant and non-pregnant animals were examined: 2,809 from Marajó Island and 1,108 from the mainland. The buffered acidified plate antigen (BAPA) screening test positively diagnosed 4.8 % (188/3,917) of the animals with brucellosis, and the 2-mercaptoethanol (2-ME) confirmatory test affirmed 95.7 % (180/188) of the results. The brucellosis prevalence was 4.17 times greater in mainland animals than on Marajó Island, with the highest prevalence in Tailândia (11.30 %) and Paragominas (12.38 %). Brucellosis seroprevalence was significantly influenced (p?<?0.05) by reproductive status, with pregnant females being most vulnerable. These results demonstrate that brucellosis infection is active in the Brazilian region containing the largest buffalo population and that this disease poses a threat to public health and buffalo production in Pará.  相似文献   

15.
Intestinal parasites, both helminths and protozoa, are commonly found in domestic animals, and the possible transmission of enteric parasites from dogs and cats to humans may constitute a global potential health risk worldwide. In the present study, we analysed 148 stool samples from dogs (n=126) and cats (n=22) collected from animal shelters and veterinary clinics, in the district of évora, Portugal. Microscopic examination confirmed that Giardia was the most frequent parasite in the studied population (34/148; 23%). Other parasites such as Ancylostoma sp., Isospora spp., Toxocara, Trichuris spp., Toxascaris and Toxoplasma were also found. Furthermore, molecular characterization of Giardia duodenalis analysis targeting the small subunit ribosomal RNA (ssu-rRNA) was performed revealing the presence of host-specific (C and D) and zoonotic assemblages (A and B). This work points out to the importance of protozoan parasites in companion animals, and reanalyses the need for parasite prophylaxis.  相似文献   

16.
Blowfly strike and the methods used to combat blowfly strike were recorded on 33 properties in the R?ens area of South Africa during 2003/2004. Data were recorded on Merino and Dohne Merino hoggets (n = 4951) with at least 3 months' wool growth. The following data were captured: presence or absence of strike, site of the strike (body or breech), presence or absence of dermatophilosis as well as subjective scores for wool quality and wool colour. Control measures recorded include: chemical treatment (preventative and spot treatment), crutching, mulesing and the use of the Lucitrap system. Blowfly strike was not significantly influenced by gender or breed. Hoggets suffering from dermatophilosis were more likely to be struck, compared with contemporaries not suffering from the skin disorder (0.057 vs 0.027; P < 0.05). Merino hoggets generally had higher scores than their Dohne Merino contemporaries for wool quality (32.6 vs 27.4; P < 0.05) and wool colour (29.0 vs 27.2; P < 0.05). There was an indication that the Lucitrap system may have reduced flystrike, but the effect was not statistically significant (P = 0.19 for overall strikes and P = 0.12 for body strike). The Mules operation benefited overall flystrike (0.013 vs 0.110; P < 0.05); mainly through an effect on breech strike (0.010 vs 0.109; P < 0.05). The proportion of fly strikes increased with wool length, and declined with an increase in farm size in wool colour score. None of the ethically acceptable control measures assessed could substantially reduce blowfly strike on their own, and an integrated pest management programme was proposed.  相似文献   

17.
ObjectiveDetermine arterial blood pressure range that diplomates of the American College of Veterinary Anesthesia and Analgesia (ACVAA) and European College of Veterinary Anaesthesia and Analgesia (ECVAA) use to define intraoperative hypotension in dogs and identify the threshold values used for intervention.Study designSurvey of veterinary anesthesia specialists.PopulationDiplomates of the ACVAA and ECVAA.MethodsACVAA and ECVAA diplomates (n=313) were invited to participate in an Internet-based survey regarding anesthetized healthy dogs undergoing two types of procedures (diagnostic or surgical).ResultsThere were 151 respondents to the survey; 70.2% were ACVAA diplomates and 29.8% were ECVAA diplomates. The majority of the respondents (70.9%) worked in academia while the others were in private practice (19.2%), or research, diagnostic or pharmaceutical fields (9.9%). Hypotension was defined (mean ± SD) by the respondents as systolic arterial blood pressure (SAP) <87 ± 8 mmHg for surgical cases and <87 ± 6 mmHg for diagnostic cases, or mean arterial pressure (MAP) <62 ± 4 mmHg for both types of cases. Arterial pressures reported to prompt treatment were SAP 85 ± 13 mmHg or MAP 61 ± 4 mmHg in surgical cases, and SAP 84 ± 11 mmHg or MAP 63 ± 8 mmHg in diagnostic cases.Conclusions and clinical relevanceThere was agreement between ACVAA and ECVAA diplomates on the definition of intraoperative hypotension in dogs during anesthesia. The blood pressures used to define hypotension were similar to the pressures that would prompt diplomates to start treatment. Readers could infer that diplomates define hypotension as a clinical condition that requires treatment at the time of diagnosis.  相似文献   

18.
We used several large data sets at a range of temporal and spatial scales to document the land-use/land-cover change (LULCC) dynamics of the semi-arid Succulent Karoo and Nama-Karoo biomes of South Africa. More than 95% of the Karoo is comprised of land classified as Natural, which has been relatively stable since 1990. Over the last 100 years cultivation, as well as the number of domestic livestock, has declined significantly in both biomes. Protected areas have increased since 1980 to comprise nearly 8% of the Succulent Karoo biome, although they only cover 1.6% of the Nama-Karoo biome. There has been a significant recent increase in renewable energy installation applications, which cover 4% of the Karoo drylands. The trend in vegetation productivity (NDVI; 1982–2015) is unchanged over 90% of both biomes, while nearly 10% of the Karoo has shown a significant increase in NDVI trend. An analysis of repeat photographs shows that vegetation cover has either remained unchanged or has increased at most locations. Although the Karoo drylands appear less degraded than they were in the mid-twentieth century, on-going monitoring at different temporal and spatial scales is essential to evaluate the future impact of LULCC on these semi-arid environments.  相似文献   

19.
Su  Q. L.  Song  H. Q.  Lin  R. Q.  Yuan  Z. G.  Yang  J. F.  Zhao  G. H.  Huang  W. Y.  Zhu  Xing Quan 《Tropical animal health and production》2010,42(8):1805-1808
Candidatus Mycoplasma haemobos” is a hemoplasma species found in cattle and has been recently reported in Switzerland and Japan. In this study, “Candidatus Mycoplasma haemobos” was shown to occur in cattle and buffalo in tropical China by PCR amplification and sequence analysis of the 16S rRNA gene from blood samples. Based on the 16S rDNA sequence, a specific PCR assay was developed. Occurrence of “Candidatus Mycoplasma haemobos” in cattle and buffalo in Guangxi, China, was determined by examining 25 buffalo blood samples, 12 yellow cattle blood samples and 42 dairy cow blood samples. The results showed that 32% (8/25) of buffalo, 41.7% (5/12) of yellow cattle, and 14.3% (6/42) of dairy cows were positive for “Candidatus Mycoplasma haemobos”, respectively. Direct sequencing of representative PCR products confirmed that the amplified partial 16S rDNA sequence represented “Candidatus Mycoplasma haemobos”. This is the first report of “Candidatus Mycoplasma haemobos” in buffalo, yellow cattle, and dairy cows in China.  相似文献   

20.
The hump-back relationship between species diversity and productivity predicts highest species richness at intermediate levels of biomass, and low species numbers in least and most productive habitats. Sodic patches of semi-arid savannas are considered ‘nutrient hotspots’ by producing high-quality forage. The impact of biomass reduction (due to overgrazing) and accumulation (in the absence of herbivores) on herbaceous species richness and diversity is still unknown for these hotspots. We tested the relationship between biomass and herbaceous species richness/diversity in savanna sodic sites across varying biomass levels obtained through different herbivore exclosures. LOWESS and quadratic regression analyses revealed a unimodal species richness/ diversity–biomass relationship for biomass <2 500?kg ha?1. Species richness and diversity in the sodic zone peaked at 1 300?kg ha?1, followed by a steady decline. At biomass levels exceeding 2 500?kg ha?1, i.e. where herbivores have been excluded for 10 years, the decline in species richness and diversity stabilised. Despite many debates surrounding unimodal relationships and the intermediate disturbance hypothesis, this study confirmed a peak in species richness and diversity at intermediate biomass levels in a herbivory-adapted ecosystem. Herbivores drive ecosystem heterogeneity and enhance herbaceous species richness and diversity by keeping biomass at intermediate levels (i.e. <2 500?kg ha?1 for this sodic site).  相似文献   

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