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Thesis(M. A. Agricultural Management (Animal Production)) -- University of Limpopo, 2019 / The study was conducted to assess phenotypic and genotypic diversity in resistance to gastro-intestinal nematode (GIN) within communal goats in different agro-ecological zones of Limpopo province. Eighty goats were randomly sampled from Mopani = 20, Blouburg = 20, Vhembe = 20 and Capricorn = 20, representing four agro-ecological zones of Limpopo province. Frequencies and percentages of occurrence of qualitative traits and least square means (LSM) of quantitative traits were computed. Goats were characterized as multi-coloured (67.7%), black dominant coat colour (40%), flat face profile (73.8%), erect ears (68.75%), slopping rump (47.5%), no toggles (83.8%), horned (86.3%), while 71.0% and 59.4% were straight shaped and orientated backward respectively, in all agro-ecological zones. Faecal and blood samples were collected to assess the prevalence of GIN and genetic diversity of goats. The highest prevalence and abundance GIN parasites were Haemonchus contortus (nematode = 357.42) followed by Fasciola hapatica (trematode = 163) and Moniezia (cestodes = 121.50). The patterns of GIN prevalence varied (P < 0.05) across agro-ecological zones and seasons. Prevalence of Moniezia nematode varied (P < 0.05) amongst goat sexes, whilst prevalence of other GIN’s did not vary (P>0.05). For genetic variation in GIN resistance, goats were genotyped at 15 microsatellite markers recommended by the International Society of Animal Genetics. Expected heterozygosity (HE) ranged from 0.69 in arid zone goat population to 0.76 in sub-humid zone goat population, while the observed heterozygosity (HO) ranged from 0.53 in arid zone goat population to 0.60 in sub-humid zone goat population. Mean number of alleles (MNA) per population ranged from 6.13 to 7.40. Gene differentiation (FST) among populations was low (3.6%). The results revealed that genetic relationships between populations do not reflect their geographical proximity as revealed by the Nei’s genetic distance results. Low heterozygosity resulted in reducing some fitness traits for GIN parasite resistance. Inbreed goats showed low internal parasite resistance across all agro-ecological zones.

Made available in DSpace on 2016-12-23T13:56:02Z (GMT). No. of bitstreams: 1 VERSAO FINAL renata abdalla.pdf: 1003993 bytes, checksum: 53f705da825f69f2791052150b4e5522 (MD5) Previous issue date: 2008-11-23 / Este estudo tem o propósito de contribuir para o entendimento dos fatores que determinam as parasitoses intestinais entre crianças aparentemente expostas às mesmas condições socioeconômicas e ambientais, em área rural do sul do Estado do Espírito Santo. Trata-se de um estudo de prevalência nas áreas de assentamento rural do Município de Alegre. O tamanho da amostra foi de 133 crianças de 6 meses a 12 anos. Foi coletado sangue e fezes e aplicado questionário no período de junho a agosto de 2006. Para análise dos dados, foi conduzido um modelo hierárquico e utilizado o Statistical Package for the Social Sciences (SPSS), versão 14.0. Os resultados são apresentados em três sessões: na primeira, a prevalência das parasitoses intestinais e das variáveis preditoras; na segunda, análise bivariada e regressão logística, em dois modelos de análise, e, na terceira, a distribuição espacial dos casos. Verificou-se uma prevalência de 21,80% de crianças parasitadas. A análise de regressão logística por bloco revelou que foram estatisticamente significantes para parasitoses as seguintes variáveis: escolaridade paterna, número de habitantes por domicílio, água para consumo, hábito de lavar as mãos após defecar, número de refeições, consulta médica em 2005, uso de vermífugo anterior à pesquisa e hábito de lavar as mãos antes das refeições. Na análise de regressão logística final, em ambos modelos, as variáveis que se mantiveram estatisticamente significantes foram: número de habitantes por domicílio e água para consumo. Os dados do presente estudo confirmam a necessidade de políticas públicas no sentido de melhorar a qualidade de vida desta população rural e a continuidade dos estudos nessa área faz-se necessária para que se alcance esta melhora. / The purpose of this study is to contribute to the understanding of the determinant factors of intestinal nematode among children that share the same socio economic condition in a rural area in the south of Espírito Santo State. This is a prevalence study in rural land settlement areas from the municipality of Alegre. The sample size was 133 children. It was collected blood and feces and performed a questionnaire from June to August, 2006. Then, it was conducted a hierarchial model and the data were analyzed by Statistical Package for the Social Sciences (SPSS) version 14.0. The results are seen in tree sections: first, the prevalence of intestinal nematodes and predictors variables, second, bivariate analysis and logistic regression model and third, the especial distribution of the cases. It was verified a prevalence of 21,80% of infected children. In the logistic regression by blocs we found a statistic significance between intestinal nematodes and father education, number of people at home, water supplies, habits of cleaning hands after using a bathroom, number of meals a day, seen a doctor in 2005, use of anti-nematode drugs and habits of cleaning hands before meals. In the final logistic regression, both models had the same variable statistic significance which was: number of people at home and water supplies. The data to present study confirms the need of public politics in order to improve the quality of life for this rural population and continuity of the studies on these areas is necessary to reach this marks.

This thesis was conducted to evaluate important epidemiological features of Gastro-Intestinal Nematode (GIN) infections in Ontario sheep flocks; namely, the PeriParturient Egg Rise (PPER), overwintering of GIN free-living stages on pasture, and Anthelmintic Resistance (AR). Three main studies were carried out: a longitudinal study was conducted on six sheep farms to evaluate the PPER in ewes lambing in different seasons and to determine whether total plasma protein (TPP) levels and packed cell volume (PCV) were associated with increased fecal GIN-egg shedding. Secondly, a pilot-study was conducted on three farms to describe pasture-level environmental conditions and over-wintering survival and infectivity of free-living GIN larvae, especially Haemonchus contortus. Lastly, a cross-sectional study was conducted on 47 sheep farms in Ontario, to evaluate the frequency of AR, compare different diagnostic tests for AR, and evaluate management practices associated with AR. In the longitudinal study, the PPER was observed in winter, spring and autumn lambing ewes, though the magnitude and distribution of the PPER varied with season. Lower TPP and PCV values were associated with increased fecal GIN-egg counts. The pilot-study suggested that H. contortus larvae did not overwinter successfully on pasture, while other GINs, such as Teladorsagia sp., Trichostrongylus spp. and Nematodirus spp., were able to overwinter on pasture, and were infective the following spring. Resistance to ivermectin, fenbendazole and levamisole was demonstrated on 97% (28/29), 95% (19/20) and 6% (1/17) respectively of the farms tested; most of the resistance observed was found in Haemonchus sp. The Fecal Egg Count Reduction percentage following treatment was influenced by which mean (i.e. arithmetic vs. geometric) was used in the formula; use of pre-treatment in addition to post-treatment faecal egg counts was not influential. Both the fecal egg count reduction test and the larval development assay diagnosed resistance, but there was poor agreement between the two tests, as indicated by the Kappa test. The prior use of benzimidazoles on farms was associated with higher levels of fenbendazole resistance. The information generated in this thesis will be used to develop a parasite control program for sheep flocks in Ontario and to guide future research on GIN parasitism. / New Directions - Ontario Ministry of Agriculture, Food and Rural Affairs; Ontario Sheep Marketing Agency; Ontario Agriculture Centre Canada; Merial; Animal Health Strategic Initiative - University of Guelph Partnership; Undergraduate Research Assistantship; Gartshore Memorial Sheep Scholarship;

<p>Vr&scaron;eno je istraživanje intestinalnih nematoda žutogrlog mi&scaron;a (<em>Apodemus flavicollis&nbsp; </em>Melchior, 1834) uzorkovanog sa 18 lokaliteta na teritoriji Srbije, južno od Save i Dunava, sa ciljem pro&scaron;irenja i upotpunjavanja saznanja o ovoj komponenti parazitofaune glodara u ovom delu Evrope. Fauna nematoda crevnog trakta je analizirana sa vi&scaron;e aspekata: kvantitativnog, aspekta zajednica, biolo&scaron;kog, aspekta biodiverziteta i aspekta polne strukture. Pored toga, ispitan je uticaj odabranih<br />spolja&scaron;njih i unutra&scaron;njih faktora na prevalencu i abundancu parazitske infekcije.</p><p>Zabeleženo je prisustvo devet vrsta intestinalnih nematoda, pri čemu je broj vrsta po lokalitetu varirao od 1 do 7. Ukupna prevalenca infekcije iznosila je 81,6%. Najče&scaron;će vrste u uzorku bile su <em>Heligmosomoides polygyrus </em>i&nbsp;<em> Syphacia stroma</em>, koje su<br />se odlikovale najvi&scaron;im prevalencama i intenzitetima infekcije. Distribucija nematoda unutar domaćina je bila agregirana. Broj vrsta po domaćinu varirao je od 1 do 5, ali su najzastupljenije bile infekcije jednom ili dvema vrstama. Najče&scaron;ća kombinacija<br />vrsta bila je&nbsp;<em> H. polygyrus-S. stroma;</em> međutim, odsustvo podataka iz ranijih istraživanja i adekvatnih polaznih modela sprečava dono&scaron;enje zaključaka o mogućim interakcijama i asocijacijama između vrsta.</p><p>Monoksene nematode su bile brojnije i imale veću prevalencu od heteroksenih nematoda, &scaron;to oslikava&nbsp; razlike u njihovim životnim ciklusima. Među monoksenim nematodama, geohelminti u užem smislu su se odlikovali najvećim prevalencama, a ageohelminti najvećom abundancom, u skladu sa životnim strategijama koje teže ka disperziji ili akumulaciji.&Scaron;enonov indeks diverziteta cele uzoračke populacije iznosio je 1,44 &scaron;to je visoka vrednost u odnosu na one iz drugih delova Evrope. Nije uočena značajna negativna korelacija između udaljenosti lokaliteta i vrednosti Sorensenovog indeksa,ukazujući da je prostorni faktor značajan u strukturiranju zajednica intestinalnih nematoda i na lokalnom nivou. Odnos polova je bio neravnomeran, uglavnom u korist ženki, u skladu sa podacima drugih autora. Ženke su ujedno bile krupnije od mužjaka, saglasno sa ranijim nalazima za parazitske nematode. Nadmorska visina nije uticala na abundancu intestinalnih nematoda. Pol domaćina je uticao na prevalencu dve vrste: prevalenca&nbsp; <em>S. stroma</em>&nbsp; je bila veća kod mužjaka, a prevalenca<em> Trichuris muris</em>&nbsp; kod ženki. Kao značajan faktor uticao je na abundancu samo kod vrste&nbsp;<em> Aonchotheca annulosa</em>; abundanca ove vrste bila je veća kod mužjaka. Rezultati sugeri&scaron;u da je uticaj pola domaćina na nivo parazitske infekcije izuzetno kompleksan fenomen.&nbsp; Prevalenca i abundanca infekcije intestinalnim nematodama je bila veća kod domaćina sa B hromozomima.&nbsp; Lokalitet je bio značajan faktor u variranju abundance nematoda. Uzrast i prisustvo drugih vrsta nematoda su&nbsp; takođe ispoljavali značajan efekat. Povećanje abundance nematoda sa uzrastom&nbsp; se vezuje za dužu izloženost starijih jedinki parazitima. Iako je registrovan uticaj abundance jedne vrste na abundancu druge, on ne predstavlja čvrst dokaz za postojanje interakcija između vrsta.</p> / <p>A study of intestinal nematode parasites was conducted on the yellow-necked mouse (<em>Apodemus flavicollis&nbsp;</em> Melchior, 1834) sampled from 18 sites from Serbia south of the Sava and Danube rivers. The aim of the study was to broaden and enrich the data on this category of rodent parasites in this part of Europe. The nematode fauna of the gastrointestinal tract was analysed from quantitative, community, biological, biodiversity and sex ratio aspects. In addition, selected extrinsic and intrinsic factors were tested for their influence on the prevalence and abundance of infection.</p><p>Nine species of&nbsp; intestinal nematodes were noted, 1 to 7 per site. Total sample prevalence was 81.6%. <em>Heligmosomoides polygyrus</em>&nbsp; and&nbsp; <em>Syphacia stroma</em> were the most common species, with the highest prevalence and intensity values. Nematodes were aggregated within their hosts. Infracommunity richness varied from 1 to 5, but infections with one or two species were most common. The most frequent<br />combination&nbsp; of species was <em>H. polygyrus-S. stroma</em>, but in absence of prior research and adequate null models, conclusions of possible interactions and associations between species could not be drawn.</p><p>Monoxenous nematodes were more abundant and prevalent than heteroxenous species, reflecting the differences in their life cycles. Of the monoxenous nematodes, geohelminths<em> sensu stricto</em> had the highest prevalence values, whereas ageohelminths were most abundant, with respect to their life strategies that favour either dispersal or accumulation. Shannon&rsquo;s diversity index for the total sample was 1.44, a high value compared to those from other European based studies. A significant negative correlation between site distance and Sorensen index values was not found, implying that spatial factors have an important role in structuring intestinal nematode communities on a local scale. Sex ratio was generally female-biased, in agreement with data from other authors. In addition, females were larger than males, congruent with previous findings for parasitic nematodes.</p><p>Elevation did not significantly influence intestinal nematode abundance. Host sex influenced the prevalence of two species: for <em>S. stroma</em> prevalence was higher in males, and for <em>Trichuris muris</em> in females. Influence of host sex on abundance was found only for <em>Aonchotheca annulosa</em>, with abundances of this parasite higher in male mice. The results suggest that the effectof host sex on parasite infection levels is a highly complex phenomenon.&nbsp; Infection prevalence and abundance was higher in hosts that carried B chromosomes. Site was a significant factor in explaining variations in nematode abundance. Hostage and presence of other nematode species&nbsp; also exibited effects.&nbsp; An increase in nematode abundance with host age&nbsp; is explained by prolonged exposure to parasites in older host individuals. Although results indicate that the abundance of one species influences the abundance of another, this is not firm evidence of the existence of species interactions.</p>