1,721,091 research outputs found
Epidemiology and identification of Eimeria species affecting poultry in East Gojjam Zone, North West Ethiopia
Background: Despite the expansion of modernized poultry farming in Ethiopia, the presence of high prevalence of Eimeria species is the bottleneck in the sector causing high morbidity and mortality rate in poultry. Objectives: The objectives of this study were to estimate the prevalence and identify Eimeria species and investigate the major risk factors. Method: A cross-sectional study was conducted from November 2019 to April 2020 in East Gojjam Zone, North West Ethiopia. A total of 384 chickens were used. Both floatation and McMaster coprological techniques were employed. Univariate and multinomial logistic regression was used to calculate the odds ratio for the associated risk factors. Analysis of variance was used to analyse differences in Eimeria oocyst counts among the groups. Results: Overall prevalence of Eimeria species in poultry from the study area was 26.5%. Age (OR = 0.25, p = 0.001), management system (OR = 12.44, p = 0.001) and production system (OR = 0.37, p = 0.001) were found significantly (p < 0.05) associated with the risk of Eimeria species in poultry. The mean Eimeria oocyst count was significantly different by age and management system (F = 6.526, p = 0.002), (F = 5.369, p = 0.005), respectively. The mean Eimeria oocyst count was significantly greater in 6–12 weeks (p = 0.004) and <6 weeks of age (p = 0.025). A total of 6 Eimeria species were identified. Eimeria tenella (46.07%), Eimeria necatrix (24.5%) and Eimeria acervulina (8.82%) were the most common Eimeria species encountered. Conclusion: The prevalence of Eimeria species was higher in poultry in North West Ethiopia. Therefore, tailor-made intervention is required to mitigate risk factors and reduce the prevalence of Eimeria species in poultry from the study area
A Comparative Study of Mini-FLOTAC With Traditional Coprological Techniques in the Analysis of Cetacean Fecal Samples
Free-ranging cetaceans are considered sentinels for the marine ecosystem's health. New and non-invasive methods have been set up for the collection of fecal samples from free-ranging big whales at sea, permitting to gain an excellent epidemiological picture of parasitic infections in wild populations. To select the best protocol to be used for copromicroscopic examination in cetaceans stool samples, we evaluated the sensitivity of two commonly used techniques, i.e., a sedimentation-floatation method and the Mini-FLOTAC through validation by helminth isolation from the digestive tract. For this aim, gastrointestinal content and fecal samples were collected during necropsy from 44 cetaceans, including bottlenose dolphins (Tursiops truncatus), striped dolphins (Stenella coeruleoalba), sperm whales (Physeter macrocephalus), Risso's dolphins (Grampus griseus), Cuvier's beaked whales (Ziphius cavirostris), pilot whale (Globicephala melas), and fin whales (Balaenoptera physalus). Helminths were recovered through washing and filtering of the gastrointestinal contents and morphologically identified. Copromicroscopic examinations were performed on formalin-preserved fecal samples, using a sodium nitrate, sodium thiosulphate, and sucrose solution (s.g. = 1.450) for both methods. Helminths belonging to 9 taxa (i.e., the trematodes Synthesium tursionis, Synthesium delamurei, Campula palliata, Braunina cordiformis, Pholeter gastrophilus, the nematode Anisakis sp., cestodes of the family Tetrabothriidae and the acanthocephalan Bolbosoma sp.) were isolated. Eggs referable to the same taxa, with the exception of cestodes, were found in copromicroscopic analyses. Sensitivity of the Mini-FLOTAC method appeared higher or equal for all taxa, proving superior to the sedimentation-flotation method for the detection of all except Anisakis sp. The concordance of the two tests indeed revealed a moderate to perfect agreement (kappa values 0.42–1). Not excluding the limitations inherent to the techniques themselves, explanations for false-negative results at copromicroscopy could be linked to parasite-related factors, including prepatent infections, low parasitic burdens, or intermittent egg shedding. Notwithstanding these limitations, this study evidenced that the Mini-FLOTAC protocol approximates more accurately the composition of the gastrointestinal helminthic community of cetaceans from copromicroscopic examination, providing at the same time a quantitative estimatio
Comparison between two quantitative methods and two different matrix for the evaluation of parasitic burden in Hapalotrema mistroides infections.
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Quantitative monitoring of selected groups of parasites in domestic ruminants: A comparative review
Parasites have had a significant impact on domestic ruminant health and production for a long time, but the emerging threat of drug resistance urgently requires an improved approach to parasite monitoring and control activities. The study reviewed the international literature to analyze the different proposals for the sampling approach and the quantitative estimation of parasite burdens in groups of animals. Moreover, the use of thresholds to decide when and which animal to treat was also investigated. The findings of the study highlighted the presence of a wide-ranging literature on quantitative monitoring for gastrointestinal nematodes (GIN), while more limited data were found for coccidia, and no specific indications were reported for tapeworms. Concerning liver flukes, bronchopulmonary nematodes (BPN) and permanent ectoparasites (lice and mange mites), the diagnostic process is usually aimed at the detection of the parasite rather than at the burden estimation. The main research gaps that need further investigation were also highlighted. For some groups of parasites (e.g., GIN and coccidia) the quantitative approach requires an improved standardization, while its usefulness needs to be confirmed for others (e.g., BPN and lice). The development of practical guidelines for monitoring is also encouraged
An extensive survey on helminth community of Caretta caretta from the neritic feeding grounds of Northwestern Adriatic sea
The opportunistic diet of loggerhead sea turtles, Caretta caretta, their long life-span and migratory behavior contribute to shaping the diversity of the gastrointestinal helminthic community. Heteroxenous helminths are also sentinels of marine environmental health, reflecting any perturbation of the trophic chain and, indirectly, of abiotic components of the ecosystem. With the aim of studying the helminth community of a top predator such as the loggerhead sea turtle C. caretta, parasites were collected from the digestive tract of 157 individuals, stranded dead along NW Adriatic Sea in the period 2009-2023, and morphologically identified. Prevalence, intensity, abundance, relative abundance and importance index were calculated for each taxon. Ontogenetic stages and sex of the hosts, seasons and observation periods were compared to unveil any difference in parasite community structure. Overall, richness and diversity were similar to other neritic grounds in the Mediterranean Sea; helminths from 9 species were recovered, with the trematode Rhytidodes gelatinosus and the nematode Sulcascaris sulcata having the highest importance. Prevalence, intensity and abundance of helminthiases increased significantly in the period 2015-2023. Helminthic community composition and richness generally overlap with what observed in other similar neritic areas, confirming the role of the ecosystem in shaping C. caretta gastrointestinal helminthic community. Increase in prevalence and intensity of helminthiases and composition of the parasitic community throughout the observation period suggests potential alterations within the Adriatic ecosystem in its biotic and/or abiotic components, potentially associated with underlying global climate change
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
