ECOLOGICAL IMPLICATIONS OF BOVINE TUBERCULOSIS IN AFRICAN BUFFALO HERDS

Summary 1. Understanding the effects of disease is critical to determining appropriate management responses, but estimating those effects in wildlife species is challenging. We used bovine tuberculosis (BTB) in the African buffalo Syncerus caffer population of Kruger National Park, South Africa, as a case study to highlight the issues associated with estimating chronic disease effects in a long-lived host. 2. We used known and radiocollared buffalo, aerial census data, and a natural gradient in pathogen prevalence to investigate if: (i) at the individual level, BTB infection reduces reproduction; (ii) BTB infection increases vulnerability to predation; and (iii) at the population level, increased BTB prevalence causes reduced population growth. 3. There was only a marginal reduction in calving success associated with BTB infection, as indexed by the probability of sighting a known adult female with or without a calf ( P = 0·065). 4. Since 1991, BTB prevalence increased from 27 to 45% in the southern region and from 4 to 28% in the central region of Kruger National Park. The prevalence in the northern regions was only 1·5% in 1998. Buffalo population growth rates, however, were neither statistically different among regions nor declining over time. 5. Lions Panthera leo did not appear to preferentially kill test-positive buffalo. The best (Akaike’s Information Criterion corrected for small sample size) AIC c model with BTB as a covariate [exp( β ) = 0·49; 95% CI = (0·24‐1·02)] suggested that the mortality hazard for positive individuals was no greater than for test-negative individuals. 6. Synthesis and applications . Test accuracy, time-varying disease status, and movement among populations are some of the issues that make the detection of chronic disease impacts challenging. For these reasons, the demographic impacts of bovine tuberculosis in the Kruger National Park remain undetectable despite 6 years of study on known individuals and 40 years of population counts. However, the rainfall and forage conditions during this study were relatively good and the impacts of many chronic diseases may be a non-linear function of environmental conditions such that they are only detectable in stressful periods.

Bovine tuberculosis (BTB) was first detected in Kruger National Park (KNP) in a single African buffalo (Syncerus caffer) in 1990. In 1991/1992, 2,071 African buffalo were examined for BTB as part of a culling program that removed animals from all known herds in KNP. The prevalence of BTB in 1991/1992 was estimated to be 0%, 4.4% (+/-0.6%), and 27.1% (+/-1.4%), in the north, central, and south zones of KNP, respectively. In 1998, a stratified, two-stage cluster sampling method was used to estimate that the prevalence of BTB was 1.5% (+/-2.5%), 16% (+/-5.3%), and 38.2% (+/-6.3%), in the north, central, and south zones, respectively. This represented a significant increase in prevalence (P < or = 0.05) in the south and central zones, but not in the north zone. Continued monitoring of BTB in KNP is important for understanding disease transmission risks, potential population effects, and the efficacy of disease management strategies. The methodology and sample sizes used in 1998 are appropriate for future BTB monitoring in KNP.

A 12 month cross-sectional study was carried out at Lafenwa Abattoir Abeokuta, Southwestern Nigeria from July, 2011 to June, 2012. This was to determine the prevalence and economic loss of bovine tuberculosis in this abattoir. A total of 928 cases of bovine tuberculosis out of 52,273 cattle slaughtered during this period were condemned, representing a total prevalence of 1.78% (95% CI: 1.31- 2.14%). Typical tuberculous lesions were found in the Lung, Liver and Spleen, higher rate of organ condemnation was observed in the lung followed by liver and spleen. There was statistically significant difference in rate of organ condemnation (P&lt;0.05). The monthly prevalence and sequence plot revealed an epidemic tendency for bovine tuberculosis during this period and there was statistically significant difference between prevalence of bovine tuberculosis and seasonal occurrence. An estimated total loss of N1.2 million (US$7,367) due to bovine tuberculosis was observed in this abattoir for the year. It was concluded that bovine tuberculosis is prevalent with epidemic tendency in cattle destined for human consumption, also with attending serious public health implications and huge loss to both the butchers and national economy.

Bovine tuberculosis (BTB) is a disease of animal and public health importance in developing countries. In rural Ethiopia, there is potential for a shift in the epidemiologic of this disease driven by transformation of dairy industry. This includes gradual change from the traditional mixed crop-livestock husbandry practice to a semi-intensification system. It is therefore, essential to document the prevalence and risk factors of BTB to continuously update the designing and implementation of control and prevention strategies. Here, we present findings of a cross-sectional study on the prevalence and associated risk factors of BTB among cattle reared under mixed crop-livestock farming system in Tigray region, Ethiopia. A multistage purposive sampling approach was used to select districts, villages, herds and individual cattle. A total of 1,357 cattle from 310 herds were examined for BTB infection using a comparative intradermal tuberculin skin test (CIDT). Questionnaires were used to gather data on herd structure and herd management practices. A multilevel logistic mixed effect model was used to determine risk factors after accounting for clustering effect at three levels (village, herd and individual animal). Overall prevalence of BTB was 4.3% (95% CI=3.4-5.6), with the highest prevalence recorded in Alamata district (5.6%) and lowest in Korem (1.6%). Multilevel logistic mixed effect model analysis identified exotic breed (OR=3, p=0.014), closed barn (OR=2.6, p=0.018), large herd size (OR=2.6, p=0.05) and purchase of cattle (OR=2.1, p=0.027) as important risk factors for BTB. Taken together, these findings suggest that the current dairy development program centred on the introduction of exotic and or crossed animals could have contributed to changing epidemiological situations of BTB in the study area.

The present study was executed to determine the magnitude of bovine tuberculosis (BTB) in buffaloes in native type of husbandry practices and impact of certain factors in the prevalence of bovine tuberculosis in buffaloes in the Punjab, Pakistan. Three year cross sectional study was carried out on female population of Nili Ravi buffaloes (n = 2526) maintained at 10 Government Livestock Experimental Stations, and peri urban areas of the three major cites i.e., Lahore, Faisalabad and Okara. These animals were screened with comparative intradermal tuberculin test (CIDT) by using two types of tuberculins i.e., mammalian and avian. The reaction of tuberculins injected was interpreted after 72 hours post injection. The data were analyzed by Chi-square test and Pearson correlation. Relative risk and other associated factors were calculated to describe the association with prevalence of tuberculosis in buffaloes. The prevalence of bovine tuberculosis on the basis of CIDT was 12.72%. The BTB among different livestock farms varied significantly (P<0.001) from 8.52 to 19.04%. The results of epidemiological factors revealed a significantly (P<0.001) greater percentage of tuberculin reactors in >8 years old age, body weight >550 kg, 3-6 parity, pregnant animals, and animals with >7 liters milk yield. The husbandry factors which greatly influence the prevalence was poor feeding (RR=2.615), high fly density (RR= 1.3474), poor management (RR=1.315), contact with wildlife (RR=1.4507), poor farm conditions (RR=1.4708), quarantine measures (RR=1.1557) and poor sanitation of farm (RR= 1.3701).

Within the Reef Corridor of the Southwest Gulf of Mexico (rcsgm), various studies have been carried out that address one of its most important biological components: fish; however, there are still gaps in information about the group in this corridor. Although lists of fish species exist, these have not been compiled for the rcsgm reefs. Likewise, the degree of connectivity and similarity of the ichthyofaunistic assemblages present in this large corridor is unknown. The present study addresses these issues by compiling and analyzing the published literature, to know the degree of connectivity and dynamics of community assemblages throughout the northern, central and southern regions of the rcsgm. Taxonomic updating of the reported species was performed with the Fricke criterion, connectivity was addressed using the modified Whittaker beta diversity index (β) and community assemblages were addressed through partial canonical analysis (cca). Based on the information collected, the fish diversity of the rcsgm amounts to 525 species grouped into 34 orders, 102 families and 270 genera. The most important families that together represent 50% of the fish wealth were Serranidae (51 spp, 9.7%), Labridae (30 spp, 5.7%; Labrinae: 16 spp. and Scarinae: 14 spp), Gobiidae (30 spp, 5.7%), Carangidae (23 spp, 4.4%), Scianidae (19 spp, 3.6%), Haemulidae (18 spp, 3.4%), Pomacentridae (15 spp, 2.9%), Labrisomidae (12 spp, 2.3%), Lutjanidae (12 spp, 2.3%), Ophichthidae (11 spp, 2.1%), Paralichthyidae (11 spp, 2.1%) as well as Muraenidae, Clupeidae and Sparidae who presented 10 species (1.9%). At the regional level, the central region stands out, which includes the Veracruzano Reef System (sav) with 494 species, followed by the northern region that includes the Lobos-Tuxpan Reef System (salt) with 326 species and finally the southern region that houses the Los Tuxtlas reefs (at) with 128 species. At the reef level, Lobos stands out in the northern region with 259 spp, Verde reef in the central region with 144 spp and the Palo Seco reef in the southern region with 106 spp. Through β diversity, it was estimated that the regions that maintain greater connectivity are the northern region with the central region (β: 0.28), and to a lesser extent the central region with the southern region (β: 0.59). The cca analysis detected that fish community assemblages are particular to each region, that is, they differ among them; However, there are submerged reefs that show changes in their community structure in both the northern and central regions, which could be attributed to their origins (coral, non-coral). In the central region, the Negrillo and Resuella reefs (sedimentary rocky reefs) tend to separate from the emerging coral reefs; while the submerged coral reefs Piedras Altas, Cabo Nuevo and Corazones are separated from the emerging coral reefs of the northern region. The present study updates the information on fish in the rcsgm and provides guidelines to understand connectivity, as well as changes in community assemblages within and between the broad regions and reef systems that make up this corridor. Key words: Ichthyofauna, diversity, richness, connectivity, coral reefs, Veracruz.

Mycobacterium bovis, the causative agent of bovine tuberculosis (BTB), is endemic in the Kruger National Park (KNP), South Africa. African lions ( Panthera leo ) are susceptible to BTB, but the impact of the disease on lion populations is unknown. In this study, we used a novel gene expression assay for chemokine (C-X-C motif) ligand 9 (CXCL9) to measure the prevalence of M. bovis infection in 70 free-ranging lions that were opportunistically sampled in the southern and central regions of the KNP. In the southern region of the KNP, the apparent prevalence of M. bovis infection was 54% (95% confidence interval [CI]=36.9-70.5%), compared with 33% (95% CI=18.0-51.8%) in the central region, an important difference (P=0.08). Prevalence of M. bovis infection in lions showed similar patterns to estimated BTB prevalence in African buffaloes ( Syncerus caffer ) in the same areas. Investigation of other risk factors showed a trend for older lions, males, or lions with concurrent feline immunodeficiency virus infection to have a higher M. bovis prevalence. Our findings demonstrate that the CXCL9 gene expression assay is a useful tool for the determination of M. bovis status in free-ranging lions and identifies important epidemiologic trends for future studies.

Bovine tuberculosis reactor cattle in Southwest Ethiopia: Risk factors for bovine tuberculosis

Assessing vaccination as a control strategy in an ongoing epidemic: Bovine tuberculosis in African buffalo

Providing an evidence base for wildlife population management is difficult, due to limited opportunities for experimentation and study replication at the population level. We utilized an opportunity to assess the outcome of a test and cull programme aimed at limiting the spread of Mycobacterium bovis in African buffalo. Buffalo act as reservoirs of M.bovis, the causative agent of bovine tuberculosis (BTB), which can have major economic, ecological and public health impacts through the risk of infection to other wildlife species, livestock and surrounding communities. BTB prevalence data were collected in conjunction with disease control operations in Hluhluwe-iMfolozi Park, South Africa, from 1999 to 2006. A total of 4733 buffalo (250-950 per year) were tested for BTB using the single comparative intradermal tuberculin (SCIT) test, with BTB-positive animals culled, and negative animals released. BTB prevalence was spatially and temporally variable, ranging from 2.3% to 54.7%. Geographic area was a strong predictor of BTB transmission in HiP, owing to relatively stable herds and home ranges. Herds experiencing more intensive and frequent captures showed reduced per capita disease transmission risk and less increase in herd prevalence over time. Disease hot spots did not expand spatially over time, and BTB prevalence in all but the hot spot areas was maintained between 10% and 15% throughout the study period. Our data suggest that HiP's test and cull programme was effective at reducing BTB transmission in buffalo, with capture effort and interval found to be the crucial components of the programme. The programme was thus successful with respect to the original goals; however, there are additional factors that should be considered in future cost/benefit analyses and decision-making. These findings may be utilized and expanded in future collaborative work between wildlife managers, veterinarians and scientists, to optimize wildlife disease control programmes and mitigate conflict at the interface of conservation, agricultural and urban areas.

The present study was carried out to determine the prevalence of bovine and avian tuberculosis in cattle by using bovine and avian PPDs at Bangladesh Livestock Research Institute (BLRI) Cattle Farm, Savar, Dhaka. Cattle of different breeds, ages and sexes (n=183) were tested using bovine and avian PPDs. In caudal Fold Tuberculin (CFT) test, 16 (8.74%) cases were showed positive reaction among 183 sample. The overall percentages of positive reactors to Comparative cervical tuberculin (CCT) test of bovine and avian tuberculosis were 7.10% and 1.64% respectively. An insignificant variation (P&gt;0.05) on prevalence of bovine tuberculosis on different age group of cattle was observed. Age group &gt;7 years showed a higher prevalence (10.91%) than those of other age groups. In CCT test, 7.55% and 4.17% positive reactors were found in female and male cattle respectively. The association between different breeds of the animal was found significant (P&lt;0.05). The local breed showed higher prevalence (9.77%) than those of Red Chittagong and cross breed. The highest percentage (10.45%) of positive reactors in CCT test was recorded in milking cows than in dry cows (2.32%), heifer (9.52%) and calf (5.77%) were observed. Mixed infection (bovine and avian type of tuberculosis) was recorded 1.64%.Asian J. Med. Biol. Res. September 2017, 3(3): 352-356

Research Article| March 01, 1970 Great Barrier Reef: Regional Variation in a Terrigenous-Carbonate Province W. G. H MAXWELL; W. G. H MAXWELL Department of Geology and Geophysics, University of Sydney, Sydney, N.S.W., Australia Search for other works by this author on: GSW Google Scholar JONATHAN P SWINCHATT JONATHAN P SWINCHATT Department of Geology, Colgate University, Hamilton, New York 13346 Search for other works by this author on: GSW Google Scholar Author and Article Information W. G. H MAXWELL Department of Geology and Geophysics, University of Sydney, Sydney, N.S.W., Australia JONATHAN P SWINCHATT Department of Geology, Colgate University, Hamilton, New York 13346 Publisher: Geological Society of America Received: 29 Oct 1968 Revision Received: 16 Jul 1969 First Online: 02 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Copyright © 1970, The Geological Society of America, Inc. Copyright is not claimed on any material prepared by U.S. government employees within the scope of their employment. GSA Bulletin (1970) 81 (3): 691–724. https://doi.org/10.1130/0016-7606(1970)81[691:GBRRVI]2.0.CO;2 Article history Received: 29 Oct 1968 Revision Received: 16 Jul 1969 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation W. G. H MAXWELL, JONATHAN P SWINCHATT; Great Barrier Reef: Regional Variation in a Terrigenous-Carbonate Province. GSA Bulletin 1970;; 81 (3): 691–724. doi: https://doi.org/10.1130/0016-7606(1970)81[691:GBRRVI]2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The Great Barrier Reef Province is distinguished from other carbonate areas by (1) very extensive development of shelf reefs, (2) widespread terrigenous facies, and (3) a relatively deep shelf with free water circulation.The Province occupies 100,000 sq mi of the continental shelf and varies in width from 180 mi in the south to 10 mi at latitude 14° S. Regional deepening from north to south, together with regional variation in reef morphology, permits division of the Province into Northern, Central, and Southern Regions, with boundaries at 16° S., and 20° to 21° S. Geologically, the shelf is an integral part of the Tasman Geosynclinal belt, consisting of submeridional basins and highs. Main reef development has occurred along the tectonic highs.Prolific reef growth in the Northern and Southern Regions is enhanced by oceanic currents impinging directly on the shelf, whereas in the Central Region, sparse growth results partly from less effective oceanic circulation and partly from weaker tidal activity. Local hydrological conditions influence reef morphology, since reefs expand in directions where water (and substrate) conditions are most favorable. Reefs vary in form from concentric platform reefs with shallow lagoons to linear reefs which tend to recurve at the ends, ultimately forming closed ring reefs, similar to platform reefs but characterized by deep lagoons. "Resorbed" reefs are found in areas of unfavorable water conditions. The Northern Region is dominated by linear shelf-edge reefs, the Central Region by platform and resorbed reefs and the Southern Region by a massive development of lagoonal and elongate platform reefs and ring reefs.The regional facies pattern reflects a western terrigenous source, an eastern carbonate source, and a central shelf zone which shows minor influence from either source. Local divergence from this is caused by variation in (1) shelf width and depth, (2) rate of supply and type of material delivered to the shelf, and (3) age and history of the local area. Thus, in the Southern Region where the wide shelf has a deep axial trough, a poor source of terrigenous sediments, and a massive source of carbonate, the facies pattern is characterized by a band of nearshore coarse, relict, terrigenous sands, an axial zone of modern terrigenous muds and a Marginal Shelf with high carbonate (80 percent) sediments. In the Northern Region, the shelf is narrow and has a relatively strong terrigenous source; coarse, coastal terrigenous sands are followed seaward by a wedge of terrigenous muds prograding over coarse relict quartz sands which occur within one mile of individual reefs; inter-reef sediments contain both fine terrigenous and carbonate components.In the Great Barrier Reef Province, contemporary dispersal processes appear to be ineffective, and there is a general lack of accumulation of modern sediment over most of the shelf. Substantial modern deposition is represented only by terrigenous muds adjacent to the coast in the north and in the axial shelf area in the south, and by carbonate sediments on actively forming reefs, in localized areas associated with specific reefs, and in major inter-reef passages. Elsewhere, deposition is limited. This pattern probably will remain stable until advent of a regressive sea-level phase.Marked physical and chemical differences exist between the Great Barrier Reef Province and the Florida-Bahamas Province. In the Bahamas, diverse grain types reflect local environmental variation; in the Great Barrier Reef Province, carbonate grains are almost entirely of skeletal origin and environmental differences are reflected in relative abundance of different skeletal elements. On the other hand, sediment texture and composition as well as reef distribution in both areas reflect primary hydrologic control. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Despite extensive investigation, the tectono‐thermal evolution of the Archean crust in the Lewisian Gneiss Complex in NW Scotland (LGC) is debated. Most U–Pb zircon geochronological and metamorphic studies have focused on rocks from the central region of the mainland LGC, where granulite facies assemblages associated with the oldest (Badcallian) tectono‐metamorphic event at c. 2.75 Ga are overprinted by younger amphibolite facies assemblages related to the Inverian (c. 2.5 Ga) and subsequent Laxfordian (c. 1.9–1.65 Ga) tectono‐thermal events. In the southern and northern regions of the mainland LGC, deformation and metamorphism associated with the Laxfordian event are pervasive, although the timing and conditions are poorly constrained. Here, we present new field, petrographic and structural data, U–Pb zircon and titanite geochronology and phase equilibrium modelling of amphibolite samples from the northern and southern regions. Our field observations show that in both regions, pre‐Laxfordian structures are significantly reworked by steep NW‐striking fabrics that are themselves pervasively overprinted by co‐axial deformation and amphibolite facies metamorphism related to the Laxfordian event. In situ U–Pb titanite geochronology yields Laxfordian ages of 1853 ± 20 Ma in the southern region (P = 6–8 kbar and T = 640–690°C) and 1750 ± 20 Ma and 1776 ± 10 Ma in the northern region (P = 6–7.5 kbar and T = 740–760°C). While U–Pb dating of zircon rims from felsic gneisses in the central region shows a dominant Inverian metamorphic overprint at c. 2500 Ma, zircon rims in felsic gneisses from the northern and southern regions commonly yield Laxfordian dates as young as c. 1800 Ma. Combined, the results support the idea that, during the Palaeoproterozoic, the central region of the LGC acted as low‐strain domain, in which intense deformation and metamorphism were restricted to crustal‐scale shear zones. By contrast, in the southern and northern regions, early (c. 1.85 Ga) and late (c. 1.75 Ga) Laxfordian deformation and fluid‐mediated metamorphism were much more pervasive and at higher P–T conditions than previously proposed. The diachronous Laxfordian evolution of the southern and northern regions indicate that they reflect early and late snapshots of collisional to transpressional tectonics in the mainland LGC. The long‐lasting Laxfordian evolution documents the collision of the Rae and North Atlantic cratons during the Palaeoproterozoic amalgamation of the supercontinent Nuna, with implications for the palaeogeographic configuration of NW Scotland during Palaeoproterozoic Nuna.

The endemic presence of bovine tuberculosis (BTB) in African buffaloes in South Africa has severe consequences for BTB control in domestic cattle, buffalo ranching and wildlife conservation, and poses a potential risk to public health. This study determined the BTB prevalence in free-ranging buffaloes in two game reserves and assessed the influence of the prevalence of mycobacterial infections on the performance of a commercial cattle-specific serological assay for BTB (TB ELISA). Buffaloes (n = 997) were tested with the tuberculin skin test and TB ELISA; a subset (n = 119) was tested longitudinally. Culture, PCR and sequencing were used to confirm infection with M. bovis and/or non-tuberculous mycobacteria (NTM). Prevalence of BTB, but not NTM, influenced the TB ELISA performance. Multiple testing did not increase test confidence. The findings strongly illustrate the need for development of novel assays that can supplement existing assays for a more comprehensive testing scheme for BTB in African buffaloes.

To evaluate Vietnamese shallot strains as genetic resources, genetic variation among those collected from three main (northern, central and southern) regions in Vietnam was studied, based on morphology, physiology, and polymorphisms of nuclear, chloroplast, and mitochondrial DNAs. Strains from the northern region had spreading and dark green leaves, bolted late, and formed bulbs early. The bulb skin was white during bulb formation but turned brown after harvest. By contrast, strains from the central and southern regions, that had semi-spreading leaves, bolted early and formed bulbs late. The leaves were yellow green when young, but turned dark green as they matured. The bulb skin was pink when the bulbs were young but became red after harvest. In the dendrogram based on RAPD analysis of total DNA, two groups of strains were formed. One included the strains from the northern region and the other the strains from the central and southern regions. PCR-RFLP analyses of chloroplast and mitochondrial DNAs showed no variation among the strains from the three regions. From the results, two different types of shallot were identified, namely the North type (distributed in the northern region) and the South type (in the central and southern regions). Different characteristics of these two types will be useful for future breeding of shallot, common onion, and wakegi onion in tropical and sub-tropical countries.