The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo
Identifieur interne : 000E18 ( Istex/Corpus ); précédent : 000E17; suivant : 000E19The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo
Auteurs : G. Hendrickx ; A. Napala ; B. Dao ; K. Batawui ; P. Bastiaensen ; R. De Deken ; A. Vermeilen ; J. Vercruysse ; J. H. W SlingenberghSource :
- Veterinary Parasitology [ 0304-4017 ] ; 1999.
English descriptors
Abstract
This paper reports on an area wide study of all major variables determining the expression of trypanosomosis in cattle in the subhumid eco-zone of West Africa, taking Togo as an example. To enable systematic area-wide sampling, the country was divided in 311 grid-squares of 0.125×0.125 sides. Cross-sectional surveys were then conducted to generate maps or digital layers on cattle density, herd structure, ownership and breed. These data layers, except for the breed data, were subjected to a cluster analysis in order to define spatial patterns in animal husbandry systems. This analysis revealed two main systems: one is oriented towards integration with crop-agriculture and a second towards investment in cattle. These two systems could be further characterised by incorporating breed data. Zebu cattle and their crossbreeds are more favoured in the second system. The breed distribution map shows the actual situation but also serves to predict the outcome of progressive crossbreeding. An area wide trypanosomosis survey allowed the production of prevalence maps for Trypanosoma congolense, T. vivax and the associated packed cell volume (PCV) values. A simple curvi–linear relationship was established between vector density and disease prevalence. The regression between disease prevalence and PCV for taurine and zebu plus crossbreeds separately, revealed that taurine cattle maintain a comparatively high PCV level particularly in high prevalence scenarios. The relationship between the average herd PCV and cattle density suggests that herd PCV value may provide a mirror for the number of animals not kept because of the prevailing risk. The regression between agricultural intensity and cattle density subsequently in areas with decreasing herd PCV values reveals that the level of integration of cattle in crop production decreases with a decreasing PCV. Thus, despite the presence of taurine animals in Togo, the omnipresence of tsetse in particular Glossina tachinoides, remains a major obstacle to cattle raising and indirectly mixed farming development and intensification. It is argued that only with the present type of wide scale, spatial studies it becomes possible to clarify all the major variables influencing the expression of trypanosomosis. Spatial epidemiological studies at a macro level may form the basis for area wide trypanosomosis control in West Africa.
Url:
DOI: 10.1016/S0304-4017(99)00086-2
Links to Exploration step
ISTEX:DC7952C9DC4049C901527C46E18B3C1C89A88528Le document en format XML
<record><TEI wicri:istexFullTextTei="biblStruct"><teiHeader><fileDesc><titleStmt><title xml:lang="en">The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo</title><author><name sortKey="Hendrickx, G" sort="Hendrickx, G" uniqKey="Hendrickx G" first="G" last="Hendrickx">G. Hendrickx</name><affiliation><mods:affiliation>E-mail: hendrickx.vangorp@fasonet.bf</mods:affiliation></affiliation><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 2034 Bobo Dioulasso 01, Burkina Faso</mods:affiliation></affiliation></author><author><name sortKey="Napala, A" sort="Napala, A" uniqKey="Napala A" first="A" last="Napala">A. Napala</name><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</mods:affiliation></affiliation></author><author><name sortKey="Dao, B" sort="Dao, B" uniqKey="Dao B" first="B" last="Dao">B. Dao</name><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</mods:affiliation></affiliation></author><author><name sortKey="Batawui, K" sort="Batawui, K" uniqKey="Batawui K" first="K" last="Batawui">K. Batawui</name><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</mods:affiliation></affiliation></author><author><name sortKey="Bastiaensen, P" sort="Bastiaensen, P" uniqKey="Bastiaensen P" first="P" last="Bastiaensen">P. Bastiaensen</name><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</mods:affiliation></affiliation></author><author><name sortKey="De Deken, R" sort="De Deken, R" uniqKey="De Deken R" first="R" last="De Deken">R. De Deken</name><affiliation><mods:affiliation>Tropical Institute, Nationale straat, Antwerp, Belgium</mods:affiliation></affiliation></author><author><name sortKey="Vermeilen, A" sort="Vermeilen, A" uniqKey="Vermeilen A" first="A" last="Vermeilen">A. Vermeilen</name><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</mods:affiliation></affiliation></author><author><name sortKey="Vercruysse, J" sort="Vercruysse, J" uniqKey="Vercruysse J" first="J" last="Vercruysse">J. Vercruysse</name><affiliation><mods:affiliation>Faculteit Diergeneeskunde, RUG, Salisburylaan, Merelbeke, Belgium</mods:affiliation></affiliation></author><author><name sortKey="Slingenbergh, J H W" sort="Slingenbergh, J H W" uniqKey="Slingenbergh J" first="J. H. W" last="Slingenbergh">J. H. W Slingenbergh</name><affiliation><mods:affiliation>FAO, AGAH, Via delle Terme di Caracalla, 001000 Rome, Italy</mods:affiliation></affiliation></author></titleStmt><publicationStmt><idno type="wicri:source">ISTEX</idno><idno type="RBID">ISTEX:DC7952C9DC4049C901527C46E18B3C1C89A88528</idno><date when="1999" year="1999">1999</date><idno type="doi">10.1016/S0304-4017(99)00086-2</idno><idno type="url">https://api.istex.fr/document/DC7952C9DC4049C901527C46E18B3C1C89A88528/fulltext/pdf</idno><idno type="wicri:Area/Istex/Corpus">000E18</idno><idno type="wicri:explorRef" wicri:stream="Istex" wicri:step="Corpus" wicri:corpus="ISTEX">000E18</idno></publicationStmt><sourceDesc><biblStruct><analytic><title level="a" type="main" xml:lang="en">The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo</title><author><name sortKey="Hendrickx, G" sort="Hendrickx, G" uniqKey="Hendrickx G" first="G" last="Hendrickx">G. Hendrickx</name><affiliation><mods:affiliation>E-mail: hendrickx.vangorp@fasonet.bf</mods:affiliation></affiliation><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 2034 Bobo Dioulasso 01, Burkina Faso</mods:affiliation></affiliation></author><author><name sortKey="Napala, A" sort="Napala, A" uniqKey="Napala A" first="A" last="Napala">A. Napala</name><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</mods:affiliation></affiliation></author><author><name sortKey="Dao, B" sort="Dao, B" uniqKey="Dao B" first="B" last="Dao">B. Dao</name><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</mods:affiliation></affiliation></author><author><name sortKey="Batawui, K" sort="Batawui, K" uniqKey="Batawui K" first="K" last="Batawui">K. Batawui</name><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</mods:affiliation></affiliation></author><author><name sortKey="Bastiaensen, P" sort="Bastiaensen, P" uniqKey="Bastiaensen P" first="P" last="Bastiaensen">P. Bastiaensen</name><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</mods:affiliation></affiliation></author><author><name sortKey="De Deken, R" sort="De Deken, R" uniqKey="De Deken R" first="R" last="De Deken">R. De Deken</name><affiliation><mods:affiliation>Tropical Institute, Nationale straat, Antwerp, Belgium</mods:affiliation></affiliation></author><author><name sortKey="Vermeilen, A" sort="Vermeilen, A" uniqKey="Vermeilen A" first="A" last="Vermeilen">A. Vermeilen</name><affiliation><mods:affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</mods:affiliation></affiliation></author><author><name sortKey="Vercruysse, J" sort="Vercruysse, J" uniqKey="Vercruysse J" first="J" last="Vercruysse">J. Vercruysse</name><affiliation><mods:affiliation>Faculteit Diergeneeskunde, RUG, Salisburylaan, Merelbeke, Belgium</mods:affiliation></affiliation></author><author><name sortKey="Slingenbergh, J H W" sort="Slingenbergh, J H W" uniqKey="Slingenbergh J" first="J. H. W" last="Slingenbergh">J. H. W Slingenbergh</name><affiliation><mods:affiliation>FAO, AGAH, Via delle Terme di Caracalla, 001000 Rome, Italy</mods:affiliation></affiliation></author></analytic><monogr></monogr><series><title level="j">Veterinary Parasitology</title><title level="j" type="abbrev">VETPAR</title><idno type="ISSN">0304-4017</idno><imprint><publisher>ELSEVIER</publisher><date type="published" when="1999">1999</date><biblScope unit="volume">84</biblScope><biblScope unit="issue">1–2</biblScope><biblScope unit="page" from="13">13</biblScope><biblScope unit="page" to="31">31</biblScope></imprint><idno type="ISSN">0304-4017</idno></series><idno type="istex">DC7952C9DC4049C901527C46E18B3C1C89A88528</idno><idno type="DOI">10.1016/S0304-4017(99)00086-2</idno><idno type="PII">S0304-4017(99)00086-2</idno></biblStruct></sourceDesc><seriesStmt><idno type="ISSN">0304-4017</idno></seriesStmt></fileDesc><profileDesc><textClass><keywords scheme="KwdEn" xml:lang="en"><term>Animal husbandry systems</term><term>Epidemiology</term><term>PCV</term><term>Trypanosoma spp</term><term>Trypanotolerance</term><term>West Africa</term></keywords></textClass><langUsage><language ident="en">en</language></langUsage></profileDesc></teiHeader><front><div type="abstract" xml:lang="en">This paper reports on an area wide study of all major variables determining the expression of trypanosomosis in cattle in the subhumid eco-zone of West Africa, taking Togo as an example. To enable systematic area-wide sampling, the country was divided in 311 grid-squares of 0.125×0.125 sides. Cross-sectional surveys were then conducted to generate maps or digital layers on cattle density, herd structure, ownership and breed. These data layers, except for the breed data, were subjected to a cluster analysis in order to define spatial patterns in animal husbandry systems. This analysis revealed two main systems: one is oriented towards integration with crop-agriculture and a second towards investment in cattle. These two systems could be further characterised by incorporating breed data. Zebu cattle and their crossbreeds are more favoured in the second system. The breed distribution map shows the actual situation but also serves to predict the outcome of progressive crossbreeding. An area wide trypanosomosis survey allowed the production of prevalence maps for Trypanosoma congolense, T. vivax and the associated packed cell volume (PCV) values. A simple curvi–linear relationship was established between vector density and disease prevalence. The regression between disease prevalence and PCV for taurine and zebu plus crossbreeds separately, revealed that taurine cattle maintain a comparatively high PCV level particularly in high prevalence scenarios. The relationship between the average herd PCV and cattle density suggests that herd PCV value may provide a mirror for the number of animals not kept because of the prevailing risk. The regression between agricultural intensity and cattle density subsequently in areas with decreasing herd PCV values reveals that the level of integration of cattle in crop production decreases with a decreasing PCV. Thus, despite the presence of taurine animals in Togo, the omnipresence of tsetse in particular Glossina tachinoides, remains a major obstacle to cattle raising and indirectly mixed farming development and intensification. It is argued that only with the present type of wide scale, spatial studies it becomes possible to clarify all the major variables influencing the expression of trypanosomosis. Spatial epidemiological studies at a macro level may form the basis for area wide trypanosomosis control in West Africa.</div></front></TEI><istex><corpusName>elsevier</corpusName><author><json:item><name>G Hendrickx</name><affiliations><json:string>E-mail: hendrickx.vangorp@fasonet.bf</json:string><json:string>FAO Trypanosomosis Project, BP 2034 Bobo Dioulasso 01, Burkina Faso</json:string></affiliations></json:item><json:item><name>A Napala</name><affiliations><json:string>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</json:string></affiliations></json:item><json:item><name>B Dao</name><affiliations><json:string>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</json:string></affiliations></json:item><json:item><name>K Batawui</name><affiliations><json:string>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</json:string></affiliations></json:item><json:item><name>P Bastiaensen</name><affiliations><json:string>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</json:string></affiliations></json:item><json:item><name>R De Deken</name><affiliations><json:string>Tropical Institute, Nationale straat, Antwerp, Belgium</json:string></affiliations></json:item><json:item><name>A Vermeilen</name><affiliations><json:string>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</json:string></affiliations></json:item><json:item><name>J Vercruysse</name><affiliations><json:string>Faculteit Diergeneeskunde, RUG, Salisburylaan, Merelbeke, Belgium</json:string></affiliations></json:item><json:item><name>J.H.W Slingenbergh</name><affiliations><json:string>FAO, AGAH, Via delle Terme di Caracalla, 001000 Rome, Italy</json:string></affiliations></json:item></author><subject><json:item><lang><json:string>eng</json:string></lang><value>Animal husbandry systems</value></json:item><json:item><lang><json:string>eng</json:string></lang><value>Epidemiology</value></json:item><json:item><lang><json:string>eng</json:string></lang><value>PCV</value></json:item><json:item><lang><json:string>eng</json:string></lang><value>Trypanosoma spp</value></json:item><json:item><lang><json:string>eng</json:string></lang><value>Trypanotolerance</value></json:item><json:item><lang><json:string>eng</json:string></lang><value>West Africa</value></json:item></subject><language><json:string>eng</json:string></language><originalGenre><json:string>Full-length article</json:string></originalGenre><abstract>This paper reports on an area wide study of all major variables determining the expression of trypanosomosis in cattle in the subhumid eco-zone of West Africa, taking Togo as an example. To enable systematic area-wide sampling, the country was divided in 311 grid-squares of 0.125×0.125 sides. Cross-sectional surveys were then conducted to generate maps or digital layers on cattle density, herd structure, ownership and breed. These data layers, except for the breed data, were subjected to a cluster analysis in order to define spatial patterns in animal husbandry systems. This analysis revealed two main systems: one is oriented towards integration with crop-agriculture and a second towards investment in cattle. These two systems could be further characterised by incorporating breed data. Zebu cattle and their crossbreeds are more favoured in the second system. The breed distribution map shows the actual situation but also serves to predict the outcome of progressive crossbreeding. An area wide trypanosomosis survey allowed the production of prevalence maps for Trypanosoma congolense, T. vivax and the associated packed cell volume (PCV) values. A simple curvi–linear relationship was established between vector density and disease prevalence. The regression between disease prevalence and PCV for taurine and zebu plus crossbreeds separately, revealed that taurine cattle maintain a comparatively high PCV level particularly in high prevalence scenarios. The relationship between the average herd PCV and cattle density suggests that herd PCV value may provide a mirror for the number of animals not kept because of the prevailing risk. The regression between agricultural intensity and cattle density subsequently in areas with decreasing herd PCV values reveals that the level of integration of cattle in crop production decreases with a decreasing PCV. Thus, despite the presence of taurine animals in Togo, the omnipresence of tsetse in particular Glossina tachinoides, remains a major obstacle to cattle raising and indirectly mixed farming development and intensification. It is argued that only with the present type of wide scale, spatial studies it becomes possible to clarify all the major variables influencing the expression of trypanosomosis. Spatial epidemiological studies at a macro level may form the basis for area wide trypanosomosis control in West Africa.</abstract><qualityIndicators><score>8</score><pdfVersion>1.2</pdfVersion><pdfPageSize>595 x 841 pts</pdfPageSize><refBibsNative>true</refBibsNative><keywordCount>6</keywordCount><abstractCharCount>2391</abstractCharCount><pdfWordCount>6735</pdfWordCount><pdfCharCount>38954</pdfCharCount><pdfPageCount>19</pdfPageCount><abstractWordCount>356</abstractWordCount></qualityIndicators><title>The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo</title><pii><json:string>S0304-4017(99)00086-2</json:string></pii><genre><json:string>research-article</json:string></genre><host><volume>84</volume><pii><json:string>S0304-4017(00)X0077-5</json:string></pii><pages><last>31</last><first>13</first></pages><issn><json:string>0304-4017</json:string></issn><issue>1–2</issue><genre><json:string>journal</json:string></genre><language><json:string>unknown</json:string></language><title>Veterinary Parasitology</title><publicationDate>1999</publicationDate></host><categories><wos><json:string>science</json:string><json:string>veterinary sciences</json:string><json:string>parasitology</json:string></wos><scienceMetrix><json:string>health sciences</json:string><json:string>biomedical research</json:string><json:string>mycology & parasitology</json:string></scienceMetrix></categories><publicationDate>1999</publicationDate><copyrightDate>1999</copyrightDate><doi><json:string>10.1016/S0304-4017(99)00086-2</json:string></doi><id>DC7952C9DC4049C901527C46E18B3C1C89A88528</id><score>0.039931763</score><fulltext><json:item><extension>pdf</extension><original>true</original><mimetype>application/pdf</mimetype><uri>https://api.istex.fr/document/DC7952C9DC4049C901527C46E18B3C1C89A88528/fulltext/pdf</uri></json:item><json:item><extension>zip</extension><original>false</original><mimetype>application/zip</mimetype><uri>https://api.istex.fr/document/DC7952C9DC4049C901527C46E18B3C1C89A88528/fulltext/zip</uri></json:item><istex:fulltextTEI uri="https://api.istex.fr/document/DC7952C9DC4049C901527C46E18B3C1C89A88528/fulltext/tei"><teiHeader><fileDesc><titleStmt><title level="a" type="main" xml:lang="en">The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo</title></titleStmt><publicationStmt><authority>ISTEX</authority><publisher>ELSEVIER</publisher><availability><p>©1999 Elsevier Science B.V.</p></availability><date>1999</date></publicationStmt><notesStmt><note type="content">Fig. 1: Togo, geographical and climatic features. The small graphs show rainfall (histogram) and the greenness of vegetation (areas) depicted as satellite measured normalized difference vegetation indices (NDVI), for three sites from north to south: Dapaong, Sokodé and Tsévié, respectively, referred to by a black square in (a). Seasonal clusters were obtained after hierarchical clustering of a series of remotely sensed and ground measured eco-climatical variables (Hendrickx et al., 1999). Major differences between northern clusters (A and B) and southern clusters (C and D) are a significantly higher ratio of humid over dry months in clusters C and D, and a distinctly monomodal seasonal cycle in clusters A and B (i.e. a single long dry season).</note><note type="content">Fig. 2: Factors affecting the epidemiology of African bovine trypanosomosis. Variables included in this study are in square boxes, those influenced by man are in grey shaded boxes. See text for more details.</note><note type="content">Fig. 3: Variables included in the cluster analysis to define animal husbandry patterns. Respective class limits are: (a) cattle density: 1, 5, 10, 25, >25; (b) herd size: 30, 40, 50, 75, >75; (c) number of owners per herd: 1, 2, 3, 5, >5; (d) % of rural owners: 70, 90, 95, 99, >99; (e) % of owners being agriculturists: 0, 50, 75, 90, 99, 100.</note><note type="content">Fig. 4: Map depicting the computed animal husbandry clusters (see also Table 1). Cluster A1: traditional rural systems with great potential to improve integration of cattle and agriculture. Cluster A2: intermediary system. Cluster B: (peri) urban linked system with commercial potential. Additional maps separately show sub clusters A1,2,3,4 and sub clusters B1,2,3,4.</note><note type="content">Fig. 5: Zebu introgression.The proportion of cattle with a taurine phenotype per grid-square is shown as opposed to zebu and zebu X taurine crossbreeds. Map (c) includes a 3X3 grid-square spatial smoothing to reflect a measured mobility of 14km for bulls. Classes are 100%, 90–100, 80–90, 70–80, 60–70, 50–60, 40–50, 30–40, 20–30, 10–20, 0–10. The inlaid graph shows the linear regression between the proportion of zebu alleles (selected microsatellite markers) and the observed phenotype (morphology) expressed as the proportion of cattle with taurine characteristics (R=0.940, n=17, p<10−6). Reproduced from Hendrickx et al. (1996).</note><note type="content">Fig. 6: The seasonal fluctuation of trypanosomosis per eco-zone. T. congo=T. congolense, Total=combined prevalence of T. congolense and T. vivax, PCV-p=PCV of positive cattle, PCV-n=PCV of negative cattle, PCV-t=PCV of all cattle=PCV herd. Bars reflect average rainfall intensity: light grey: dry months (<30mm rain) and dark grey: humid months (>100mm rain).</note><note type="content">Fig. 7: Spatial distribution of trypanosomosis. (A) Raw data adjusted for seasonality; (B) see A after spatial smoothing. Class limits were set to include approximately the same number of grids per class. Class upper limits for (A) are : T. congolense: 0, 2.7, 4.4, 8, 12.8, >12.8; T. vivax: 0, 2, 3.2, 4.8, 8.1, >8.1; Total prevalence: 0, 4.7, 7.1, 11, 17.6, >17.6; PCV herd: 25.5, 26.8, 27.7, 28.4, 29.8, >29.8 and for (B) : T. congolense: 0, 2.7, 4.6, 6.2, 8.1, >8.1; T. vivax: 0, 2.2, 3.4, 4.5, 6.4, >6.4; Total prevalence: 0, 5.2, 7.8, 9.8, 12.5, >12.5; PCV herd: 26.4, 27.2, 27.6, 28, 28.8, >28.8. Except for zero class approximately the same number of grid-squares are included per class.</note><note type="content">Fig. 8: Cattle breeds and vector abundance. Cattle breeds are divided in four classes: 0–33% of cattle with taurine phenotype per grid-square, 33–66%, 66–99% included, all cattle of taurine phenotype. Flags give standard error on mean. Tsetse abundance: G. tachinoides.</note><note type="content">Fig. 9: Vector abundance and disease prevalence. Fly abundance is divided in 10 subsequent classes of approximately the same size. The inlaid figure shows separate regression lines for 100% taurine grid-squares and for zebu+crossbreed grids. The computed equations for the total sample were (1) for all cattle: y=1.8697ln(x)+10.668 (R=0.488, n=171, p<10−6); (2) for taurine cattle: y=1.4621ln(x)+10.978 (R=0.377, n=45, p<0.01); for zebu+crossbreed: y=2.0738ln(x)+10.654 (R=0.533, n=126, p<10–6).</note><note type="content">Fig. 10: Influence of the breed factor on the relationship Prevalence–PCV. Breed classes are set as: 0–33% of cattle with taurine phenotype per grid-square, 33–66%, 66–99% included, all cattle of taurine phenotype. Linear regressions: (0–33%) y=−0.206x+30.669, R2=0.2591, n=28, p<0.006; (33–66%) y=−0.1509x+29.1, R2=0.460, n=27, p<10−6; (66–99%) y=−0.1188x+28.646, R2=0.1158, n=96, p<0.0007; (100%) y=−0.0441x + 27.56, R2=0.0216, n=45, not significant. Data used are raw, unadjusted for seasonal fluctuation.</note><note type="content">Fig. 11: Effect of PCV on cattle density. PCV classes are: <25 (n=9), 25–26 (n=14), 26–27 (n=29), 27–28 (n=63), 28–29 (n=23), >29 (n=7). Significance: R=0.972, n=6, p=0.0012. The area covered includes climatic clusters A and B (Fig. 1).</note><note type="content">Fig. 12: PCV and the integration cattle-crops. PCV classes are: <26 (n=23), 26–27 (n=29), 27–28 (n=63), 28–29 (n=23), >29 (n=7). The association between agriculture and cattle is defined as the slope from the linear regression of agriculture against cattle density per PCV class. The area covered includes climatic clusters A and B (Fig. 1). Agriculture is expressed as the % of land cultivated as digitised from maps derived from arial photographs (PNUD, 1984). Regressions are (from low to high PCV classes): (1) y=0.0602x+1.4335 (R2=0.135, p<0.01), (2) y=0.1188x+1.387 (R2=0.097, p<0.01), (3) y=0.1324x+0.2756 (R2=0.215; p<0.001), (4) y=0.2323x–2.3546 (R2=0.1512, p<0.01), (5) y=0.3566x+3.5711 (R2=0.3687, NS).</note><note type="content">Table 1: Animal husbandry systemsa</note><note type="content">Table 2: Correlation between riverine fly abundance and trypanosomosisa</note></notesStmt><sourceDesc><biblStruct type="inbook"><analytic><title level="a" type="main" xml:lang="en">The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo</title><author xml:id="author-1"><persName><forename type="first">G</forename><surname>Hendrickx</surname></persName><email>hendrickx.vangorp@fasonet.bf</email><note type="correspondence"><p>Corresponding author. Present address: Elsbos 24, 2650 Edegem, Belgium</p></note><affiliation>FAO Trypanosomosis Project, BP 2034 Bobo Dioulasso 01, Burkina Faso</affiliation></author><author xml:id="author-2"><persName><forename type="first">A</forename><surname>Napala</surname></persName><affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</affiliation></author><author xml:id="author-3"><persName><forename type="first">B</forename><surname>Dao</surname></persName><affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</affiliation></author><author xml:id="author-4"><persName><forename type="first">K</forename><surname>Batawui</surname></persName><affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</affiliation></author><author xml:id="author-5"><persName><forename type="first">P</forename><surname>Bastiaensen</surname></persName><affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</affiliation></author><author xml:id="author-6"><persName><forename type="first">R</forename><surname>De Deken</surname></persName><affiliation>Tropical Institute, Nationale straat, Antwerp, Belgium</affiliation></author><author xml:id="author-7"><persName><forename type="first">A</forename><surname>Vermeilen</surname></persName><affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</affiliation></author><author xml:id="author-8"><persName><forename type="first">J</forename><surname>Vercruysse</surname></persName><affiliation>Faculteit Diergeneeskunde, RUG, Salisburylaan, Merelbeke, Belgium</affiliation></author><author xml:id="author-9"><persName><forename type="first">J.H.W</forename><surname>Slingenbergh</surname></persName><affiliation>FAO, AGAH, Via delle Terme di Caracalla, 001000 Rome, Italy</affiliation></author></analytic><monogr><title level="j">Veterinary Parasitology</title><title level="j" type="abbrev">VETPAR</title><idno type="pISSN">0304-4017</idno><idno type="PII">S0304-4017(00)X0077-5</idno><imprint><publisher>ELSEVIER</publisher><date type="published" when="1999"></date><biblScope unit="volume">84</biblScope><biblScope unit="issue">1–2</biblScope><biblScope unit="page" from="13">13</biblScope><biblScope unit="page" to="31">31</biblScope></imprint></monogr><idno type="istex">DC7952C9DC4049C901527C46E18B3C1C89A88528</idno><idno type="DOI">10.1016/S0304-4017(99)00086-2</idno><idno type="PII">S0304-4017(99)00086-2</idno></biblStruct></sourceDesc></fileDesc><profileDesc><creation><date>1999</date></creation><langUsage><language ident="en">en</language></langUsage><abstract xml:lang="en"><p>This paper reports on an area wide study of all major variables determining the expression of trypanosomosis in cattle in the subhumid eco-zone of West Africa, taking Togo as an example. To enable systematic area-wide sampling, the country was divided in 311 grid-squares of 0.125×0.125 sides. Cross-sectional surveys were then conducted to generate maps or digital layers on cattle density, herd structure, ownership and breed. These data layers, except for the breed data, were subjected to a cluster analysis in order to define spatial patterns in animal husbandry systems. This analysis revealed two main systems: one is oriented towards integration with crop-agriculture and a second towards investment in cattle. These two systems could be further characterised by incorporating breed data. Zebu cattle and their crossbreeds are more favoured in the second system. The breed distribution map shows the actual situation but also serves to predict the outcome of progressive crossbreeding. An area wide trypanosomosis survey allowed the production of prevalence maps for Trypanosoma congolense, T. vivax and the associated packed cell volume (PCV) values. A simple curvi–linear relationship was established between vector density and disease prevalence. The regression between disease prevalence and PCV for taurine and zebu plus crossbreeds separately, revealed that taurine cattle maintain a comparatively high PCV level particularly in high prevalence scenarios. The relationship between the average herd PCV and cattle density suggests that herd PCV value may provide a mirror for the number of animals not kept because of the prevailing risk. The regression between agricultural intensity and cattle density subsequently in areas with decreasing herd PCV values reveals that the level of integration of cattle in crop production decreases with a decreasing PCV. Thus, despite the presence of taurine animals in Togo, the omnipresence of tsetse in particular Glossina tachinoides, remains a major obstacle to cattle raising and indirectly mixed farming development and intensification. It is argued that only with the present type of wide scale, spatial studies it becomes possible to clarify all the major variables influencing the expression of trypanosomosis. Spatial epidemiological studies at a macro level may form the basis for area wide trypanosomosis control in West Africa.</p></abstract><textClass xml:lang="en"><keywords scheme="keyword"><list><head>Keywords</head><item><term>Animal husbandry systems</term></item><item><term>Epidemiology</term></item><item><term>PCV</term></item><item><term>Trypanosoma spp</term></item><item><term>Trypanotolerance</term></item><item><term>West Africa</term></item></list></keywords></textClass></profileDesc><revisionDesc><change when="1999">Published</change></revisionDesc></teiHeader></istex:fulltextTEI><json:item><extension>txt</extension><original>false</original><mimetype>text/plain</mimetype><uri>https://api.istex.fr/document/DC7952C9DC4049C901527C46E18B3C1C89A88528/fulltext/txt</uri></json:item></fulltext><metadata><istex:metadataXml wicri:clean="Elsevier, elements deleted: ce:floats; body; tail"><istex:xmlDeclaration>version="1.0" encoding="utf-8"</istex:xmlDeclaration><istex:docType PUBLIC="-//ES//DTD journal article DTD version 4.5.2//EN//XML" URI="art452.dtd" name="istex:docType"><istex:entity SYSTEM="fx1" NDATA="IMAGE" name="fx1"></istex:entity><istex:entity SYSTEM="gr1" NDATA="IMAGE" name="gr1"></istex:entity><istex:entity SYSTEM="gr2" NDATA="IMAGE" name="gr2"></istex:entity><istex:entity SYSTEM="gr3" NDATA="IMAGE" name="gr3"></istex:entity><istex:entity SYSTEM="gr4" NDATA="IMAGE" name="gr4"></istex:entity><istex:entity SYSTEM="gr5" NDATA="IMAGE" name="gr5"></istex:entity><istex:entity SYSTEM="gr6" NDATA="IMAGE" name="gr6"></istex:entity><istex:entity SYSTEM="gr7" NDATA="IMAGE" name="gr7"></istex:entity><istex:entity SYSTEM="gr8" NDATA="IMAGE" name="gr8"></istex:entity><istex:entity SYSTEM="gr9" NDATA="IMAGE" name="gr9"></istex:entity><istex:entity SYSTEM="gr10" NDATA="IMAGE" name="gr10"></istex:entity><istex:entity SYSTEM="gr11" NDATA="IMAGE" name="gr11"></istex:entity><istex:entity SYSTEM="gr12" NDATA="IMAGE" name="gr12"></istex:entity></istex:docType><istex:document><converted-article version="4.5.2" docsubtype="fla" xml:lang="en"><item-info><jid>VETPAR</jid><aid>1630</aid><ce:pii>S0304-4017(99)00086-2</ce:pii><ce:doi>10.1016/S0304-4017(99)00086-2</ce:doi><ce:copyright type="full-transfer" year="1999">Elsevier Science B.V.</ce:copyright></item-info><head><ce:title>The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo</ce:title><ce:author-group><ce:author><ce:given-name>G</ce:given-name><ce:surname>Hendrickx</ce:surname><ce:cross-ref refid="AFF1"><ce:sup>a</ce:sup></ce:cross-ref><ce:cross-ref refid="CORR1">*</ce:cross-ref><ce:e-address>hendrickx.vangorp@fasonet.bf</ce:e-address></ce:author><ce:author><ce:given-name>A</ce:given-name><ce:surname>Napala</ce:surname><ce:cross-ref refid="AFF2"><ce:sup>b</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>B</ce:given-name><ce:surname>Dao</ce:surname><ce:cross-ref refid="AFF2"><ce:sup>b</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>K</ce:given-name><ce:surname>Batawui</ce:surname><ce:cross-ref refid="AFF2"><ce:sup>b</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>P</ce:given-name><ce:surname>Bastiaensen</ce:surname><ce:cross-ref refid="AFF2"><ce:sup>b</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>R</ce:given-name><ce:surname>De Deken</ce:surname><ce:cross-ref refid="AFF3"><ce:sup>c</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>A</ce:given-name><ce:surname>Vermeilen</ce:surname><ce:cross-ref refid="AFF2"><ce:sup>b</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>J</ce:given-name><ce:surname>Vercruysse</ce:surname><ce:cross-ref refid="AFF4"><ce:sup>d</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>J.H.W</ce:given-name><ce:surname>Slingenbergh</ce:surname><ce:cross-ref refid="AFF5"><ce:sup>e</ce:sup></ce:cross-ref></ce:author><ce:affiliation id="AFF1"><ce:label>a</ce:label><ce:textfn>FAO Trypanosomosis Project, BP 2034 Bobo Dioulasso 01, Burkina Faso</ce:textfn></ce:affiliation><ce:affiliation id="AFF2"><ce:label>b</ce:label><ce:textfn>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</ce:textfn></ce:affiliation><ce:affiliation id="AFF3"><ce:label>c</ce:label><ce:textfn>Tropical Institute, Nationale straat, Antwerp, Belgium</ce:textfn></ce:affiliation><ce:affiliation id="AFF4"><ce:label>d</ce:label><ce:textfn>Faculteit Diergeneeskunde, RUG, Salisburylaan, Merelbeke, Belgium</ce:textfn></ce:affiliation><ce:affiliation id="AFF5"><ce:label>e</ce:label><ce:textfn>FAO, AGAH, Via delle Terme di Caracalla, 001000 Rome, Italy</ce:textfn></ce:affiliation><ce:correspondence id="CORR1"><ce:label>*</ce:label><ce:text>Corresponding author. Present address: Elsbos 24, 2650 Edegem, Belgium</ce:text></ce:correspondence></ce:author-group><ce:date-received day="5" month="11" year="1998"></ce:date-received><ce:date-accepted day="25" month="3" year="1999"></ce:date-accepted><ce:abstract><ce:section-title>Abstract</ce:section-title><ce:abstract-sec><ce:simple-para>This paper reports on an area wide study of all major variables determining the expression of trypanosomosis in cattle in the subhumid eco-zone of West Africa, taking Togo as an example. To enable systematic area-wide sampling, the country was divided in 311 grid-squares of 0.125<ce:hsp sp="0.25"></ce:hsp>×<ce:hsp sp="0.25"></ce:hsp>0.125 sides. Cross-sectional surveys were then conducted to generate maps or digital layers on cattle density, herd structure, ownership and breed. These data layers, except for the breed data, were subjected to a cluster analysis in order to define spatial patterns in animal husbandry systems. This analysis revealed two main systems: one is oriented towards integration with crop-agriculture and a second towards investment in cattle. These two systems could be further characterised by incorporating breed data. Zebu cattle and their crossbreeds are more favoured in the second system. The breed distribution map shows the actual situation but also serves to predict the outcome of progressive crossbreeding. An area wide trypanosomosis survey allowed the production of prevalence maps for <ce:italic>Trypanosoma congolense</ce:italic>, <ce:italic>T. vivax</ce:italic> and the associated packed cell volume (PCV) values. A simple curvi–linear relationship was established between vector density and disease prevalence. The regression between disease prevalence and PCV for taurine and zebu plus crossbreeds separately, revealed that taurine cattle maintain a comparatively high PCV level particularly in high prevalence scenarios. The relationship between the average herd PCV and cattle density suggests that herd PCV value may provide a mirror for the number of animals <ce:italic>not</ce:italic> kept because of the prevailing risk. The regression between agricultural intensity and cattle density subsequently in areas with decreasing herd PCV values reveals that the level of integration of cattle in crop production decreases with a decreasing PCV. Thus, despite the presence of taurine animals in Togo, the omnipresence of tsetse in particular <ce:italic>Glossina tachinoides</ce:italic>, remains a major obstacle to cattle raising and indirectly mixed farming development and intensification. It is argued that only with the present type of wide scale, spatial studies it becomes possible to clarify all the major variables influencing the expression of trypanosomosis. Spatial epidemiological studies at a macro level may form the basis for area wide trypanosomosis control in West Africa.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:keywords class="keyword" xml:lang="en"><ce:section-title>Keywords</ce:section-title><ce:keyword><ce:text>Animal husbandry systems</ce:text></ce:keyword><ce:keyword><ce:text>Epidemiology</ce:text></ce:keyword><ce:keyword><ce:text>PCV</ce:text></ce:keyword><ce:keyword><ce:text><ce:italic>Trypanosoma spp</ce:italic></ce:text></ce:keyword><ce:keyword><ce:text>Trypanotolerance</ce:text></ce:keyword><ce:keyword><ce:text>West Africa</ce:text></ce:keyword></ce:keywords></head></converted-article></istex:document></istex:metadataXml><mods version="3.6"><titleInfo lang="en"><title>The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo</title></titleInfo><titleInfo type="alternative" lang="en" contentType="CDATA"><title>The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo</title></titleInfo><name type="personal"><namePart type="given">G</namePart><namePart type="family">Hendrickx</namePart><affiliation>E-mail: hendrickx.vangorp@fasonet.bf</affiliation><affiliation>FAO Trypanosomosis Project, BP 2034 Bobo Dioulasso 01, Burkina Faso</affiliation><description>Corresponding author. Present address: Elsbos 24, 2650 Edegem, Belgium</description><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">A</namePart><namePart type="family">Napala</namePart><affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">B</namePart><namePart type="family">Dao</namePart><affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">K</namePart><namePart type="family">Batawui</namePart><affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">P</namePart><namePart type="family">Bastiaensen</namePart><affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">R</namePart><namePart type="family">De Deken</namePart><affiliation>Tropical Institute, Nationale straat, Antwerp, Belgium</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">A</namePart><namePart type="family">Vermeilen</namePart><affiliation>FAO Trypanosomosis Project, BP 114 Sokodé, Togo</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">J</namePart><namePart type="family">Vercruysse</namePart><affiliation>Faculteit Diergeneeskunde, RUG, Salisburylaan, Merelbeke, Belgium</affiliation><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">J.H.W</namePart><namePart type="family">Slingenbergh</namePart><affiliation>FAO, AGAH, Via delle Terme di Caracalla, 001000 Rome, Italy</affiliation><role><roleTerm type="text">author</roleTerm></role></name><typeOfResource>text</typeOfResource><genre type="research-article" displayLabel="Full-length article"></genre><originInfo><publisher>ELSEVIER</publisher><dateIssued encoding="w3cdtf">1999</dateIssued><copyrightDate encoding="w3cdtf">1999</copyrightDate></originInfo><language><languageTerm type="code" authority="iso639-2b">eng</languageTerm><languageTerm type="code" authority="rfc3066">en</languageTerm></language><physicalDescription><internetMediaType>text/html</internetMediaType></physicalDescription><abstract lang="en">This paper reports on an area wide study of all major variables determining the expression of trypanosomosis in cattle in the subhumid eco-zone of West Africa, taking Togo as an example. To enable systematic area-wide sampling, the country was divided in 311 grid-squares of 0.125×0.125 sides. Cross-sectional surveys were then conducted to generate maps or digital layers on cattle density, herd structure, ownership and breed. These data layers, except for the breed data, were subjected to a cluster analysis in order to define spatial patterns in animal husbandry systems. This analysis revealed two main systems: one is oriented towards integration with crop-agriculture and a second towards investment in cattle. These two systems could be further characterised by incorporating breed data. Zebu cattle and their crossbreeds are more favoured in the second system. The breed distribution map shows the actual situation but also serves to predict the outcome of progressive crossbreeding. An area wide trypanosomosis survey allowed the production of prevalence maps for Trypanosoma congolense, T. vivax and the associated packed cell volume (PCV) values. A simple curvi–linear relationship was established between vector density and disease prevalence. The regression between disease prevalence and PCV for taurine and zebu plus crossbreeds separately, revealed that taurine cattle maintain a comparatively high PCV level particularly in high prevalence scenarios. The relationship between the average herd PCV and cattle density suggests that herd PCV value may provide a mirror for the number of animals not kept because of the prevailing risk. The regression between agricultural intensity and cattle density subsequently in areas with decreasing herd PCV values reveals that the level of integration of cattle in crop production decreases with a decreasing PCV. Thus, despite the presence of taurine animals in Togo, the omnipresence of tsetse in particular Glossina tachinoides, remains a major obstacle to cattle raising and indirectly mixed farming development and intensification. It is argued that only with the present type of wide scale, spatial studies it becomes possible to clarify all the major variables influencing the expression of trypanosomosis. Spatial epidemiological studies at a macro level may form the basis for area wide trypanosomosis control in West Africa.</abstract><note type="content">Fig. 1: Togo, geographical and climatic features. The small graphs show rainfall (histogram) and the greenness of vegetation (areas) depicted as satellite measured normalized difference vegetation indices (NDVI), for three sites from north to south: Dapaong, Sokodé and Tsévié, respectively, referred to by a black square in (a). Seasonal clusters were obtained after hierarchical clustering of a series of remotely sensed and ground measured eco-climatical variables (Hendrickx et al., 1999). Major differences between northern clusters (A and B) and southern clusters (C and D) are a significantly higher ratio of humid over dry months in clusters C and D, and a distinctly monomodal seasonal cycle in clusters A and B (i.e. a single long dry season).</note><note type="content">Fig. 2: Factors affecting the epidemiology of African bovine trypanosomosis. Variables included in this study are in square boxes, those influenced by man are in grey shaded boxes. See text for more details.</note><note type="content">Fig. 3: Variables included in the cluster analysis to define animal husbandry patterns. Respective class limits are: (a) cattle density: 1, 5, 10, 25, >25; (b) herd size: 30, 40, 50, 75, >75; (c) number of owners per herd: 1, 2, 3, 5, >5; (d) % of rural owners: 70, 90, 95, 99, >99; (e) % of owners being agriculturists: 0, 50, 75, 90, 99, 100.</note><note type="content">Fig. 4: Map depicting the computed animal husbandry clusters (see also Table 1). Cluster A1: traditional rural systems with great potential to improve integration of cattle and agriculture. Cluster A2: intermediary system. Cluster B: (peri) urban linked system with commercial potential. Additional maps separately show sub clusters A1,2,3,4 and sub clusters B1,2,3,4.</note><note type="content">Fig. 5: Zebu introgression.The proportion of cattle with a taurine phenotype per grid-square is shown as opposed to zebu and zebu X taurine crossbreeds. Map (c) includes a 3X3 grid-square spatial smoothing to reflect a measured mobility of 14km for bulls. Classes are 100%, 90–100, 80–90, 70–80, 60–70, 50–60, 40–50, 30–40, 20–30, 10–20, 0–10. The inlaid graph shows the linear regression between the proportion of zebu alleles (selected microsatellite markers) and the observed phenotype (morphology) expressed as the proportion of cattle with taurine characteristics (R=0.940, n=17, p<10−6). Reproduced from Hendrickx et al. (1996).</note><note type="content">Fig. 6: The seasonal fluctuation of trypanosomosis per eco-zone. T. congo=T. congolense, Total=combined prevalence of T. congolense and T. vivax, PCV-p=PCV of positive cattle, PCV-n=PCV of negative cattle, PCV-t=PCV of all cattle=PCV herd. Bars reflect average rainfall intensity: light grey: dry months (<30mm rain) and dark grey: humid months (>100mm rain).</note><note type="content">Fig. 7: Spatial distribution of trypanosomosis. (A) Raw data adjusted for seasonality; (B) see A after spatial smoothing. Class limits were set to include approximately the same number of grids per class. Class upper limits for (A) are : T. congolense: 0, 2.7, 4.4, 8, 12.8, >12.8; T. vivax: 0, 2, 3.2, 4.8, 8.1, >8.1; Total prevalence: 0, 4.7, 7.1, 11, 17.6, >17.6; PCV herd: 25.5, 26.8, 27.7, 28.4, 29.8, >29.8 and for (B) : T. congolense: 0, 2.7, 4.6, 6.2, 8.1, >8.1; T. vivax: 0, 2.2, 3.4, 4.5, 6.4, >6.4; Total prevalence: 0, 5.2, 7.8, 9.8, 12.5, >12.5; PCV herd: 26.4, 27.2, 27.6, 28, 28.8, >28.8. Except for zero class approximately the same number of grid-squares are included per class.</note><note type="content">Fig. 8: Cattle breeds and vector abundance. Cattle breeds are divided in four classes: 0–33% of cattle with taurine phenotype per grid-square, 33–66%, 66–99% included, all cattle of taurine phenotype. Flags give standard error on mean. Tsetse abundance: G. tachinoides.</note><note type="content">Fig. 9: Vector abundance and disease prevalence. Fly abundance is divided in 10 subsequent classes of approximately the same size. The inlaid figure shows separate regression lines for 100% taurine grid-squares and for zebu+crossbreed grids. The computed equations for the total sample were (1) for all cattle: y=1.8697ln(x)+10.668 (R=0.488, n=171, p<10−6); (2) for taurine cattle: y=1.4621ln(x)+10.978 (R=0.377, n=45, p<0.01); for zebu+crossbreed: y=2.0738ln(x)+10.654 (R=0.533, n=126, p<10–6).</note><note type="content">Fig. 10: Influence of the breed factor on the relationship Prevalence–PCV. Breed classes are set as: 0–33% of cattle with taurine phenotype per grid-square, 33–66%, 66–99% included, all cattle of taurine phenotype. Linear regressions: (0–33%) y=−0.206x+30.669, R2=0.2591, n=28, p<0.006; (33–66%) y=−0.1509x+29.1, R2=0.460, n=27, p<10−6; (66–99%) y=−0.1188x+28.646, R2=0.1158, n=96, p<0.0007; (100%) y=−0.0441x + 27.56, R2=0.0216, n=45, not significant. Data used are raw, unadjusted for seasonal fluctuation.</note><note type="content">Fig. 11: Effect of PCV on cattle density. PCV classes are: <25 (n=9), 25–26 (n=14), 26–27 (n=29), 27–28 (n=63), 28–29 (n=23), >29 (n=7). Significance: R=0.972, n=6, p=0.0012. The area covered includes climatic clusters A and B (Fig. 1).</note><note type="content">Fig. 12: PCV and the integration cattle-crops. PCV classes are: <26 (n=23), 26–27 (n=29), 27–28 (n=63), 28–29 (n=23), >29 (n=7). The association between agriculture and cattle is defined as the slope from the linear regression of agriculture against cattle density per PCV class. The area covered includes climatic clusters A and B (Fig. 1). Agriculture is expressed as the % of land cultivated as digitised from maps derived from arial photographs (PNUD, 1984). Regressions are (from low to high PCV classes): (1) y=0.0602x+1.4335 (R2=0.135, p<0.01), (2) y=0.1188x+1.387 (R2=0.097, p<0.01), (3) y=0.1324x+0.2756 (R2=0.215; p<0.001), (4) y=0.2323x–2.3546 (R2=0.1512, p<0.01), (5) y=0.3566x+3.5711 (R2=0.3687, NS).</note><note type="content">Table 1: Animal husbandry systemsa</note><note type="content">Table 2: Correlation between riverine fly abundance and trypanosomosisa</note><subject lang="en"><genre>Keywords</genre><topic>Animal husbandry systems</topic><topic>Epidemiology</topic><topic>PCV</topic><topic>Trypanosoma spp</topic><topic>Trypanotolerance</topic><topic>West Africa</topic></subject><relatedItem type="host"><titleInfo><title>Veterinary Parasitology</title></titleInfo><titleInfo type="abbreviated"><title>VETPAR</title></titleInfo><genre type="journal">journal</genre><originInfo><dateIssued encoding="w3cdtf">199907</dateIssued></originInfo><identifier type="ISSN">0304-4017</identifier><identifier type="PII">S0304-4017(00)X0077-5</identifier><part><date>199907</date><detail type="volume"><number>84</number><caption>vol.</caption></detail><detail type="issue"><number>1–2</number><caption>no.</caption></detail><extent unit="issue pages"><start>1</start><end>140</end></extent><extent unit="pages"><start>13</start><end>31</end></extent></part></relatedItem><identifier type="istex">DC7952C9DC4049C901527C46E18B3C1C89A88528</identifier><identifier type="DOI">10.1016/S0304-4017(99)00086-2</identifier><identifier type="PII">S0304-4017(99)00086-2</identifier><accessCondition type="use and reproduction" contentType="copyright">©1999 Elsevier Science B.V.</accessCondition><recordInfo><recordContentSource>ELSEVIER</recordContentSource><recordOrigin>Elsevier Science B.V., ©1999</recordOrigin></recordInfo></mods></metadata><serie></serie></istex></record>Pour manipuler ce document sous Unix (Dilib)
EXPLOR_STEP=$WICRI_ROOT/Wicri/Agronomie/explor/SisAgriV1/Data/Istex/Corpus
HfdSelect -h $EXPLOR_STEP/biblio.hfd -nk 000E18 | SxmlIndent | more
Ou
HfdSelect -h $EXPLOR_AREA/Data/Istex/Corpus/biblio.hfd -nk 000E18 | SxmlIndent | more
Pour mettre un lien sur cette page dans le réseau Wicri
{{Explor lien
|wiki= Wicri/Agronomie
|area= SisAgriV1
|flux= Istex
|étape= Corpus
|type= RBID
|clé= ISTEX:DC7952C9DC4049C901527C46E18B3C1C89A88528
|texte= The area-wide epidemiology of bovine trypanosomosis and its impact on mixed farming in subhumid West Africa; a case study in Togo
}}
| This area was generated with Dilib version V0.6.28. |  |