Anthelmintic effect of hidrolact of Mentha villosa Huds. (Lamiaceae) in gastrointestinal nematodes of cattle

Currently, it has been of great interest to study the anthelmintic activity of medicinal plants in ruminants. Mentha villosa Huds. (Lamiaceae) is one of the mint species that has been popularly used based on various medicinal properties, even for the control of nematode infections. This study aimed to test the anthelmintic activity of hidrolact of this plant, both in vitro, by the quantitative coproculture method, and in vivo, in calves infected with gastrointestinal nematodes, through the egg count reduction test in feces of the hosts. In in vitro tests, the hidrolact at the concentrations 40%, 60% and 80% and 100% obtained percentage of effectiveness of 91.88%, 94.15%, 98.40% and 100% respectively, showing significant ovicidal activity against gastrointestinal nematodes in calves. However, the hidrolact of M. villosa showed no in vivo anthelmintic activity at 0.1ml kg-1 day-1 on the treated animals.Atualmente, o estudo da atividade anti-helmíntica de plantas medicinais em ruminantes tem atraído bastante interesse. Mentha villosa Huds. (Lamiaceae) é uma das espécies de hortelã que tem sido utilizada popularmente devido às diversas propriedades medicinais, inclusive para o controle de verminoses. O presente estudo teve como objetivo testar a atividade anti-helmíntica do hidrolato dessa planta em bezerras infectadas por nematóides gastrintestinais, tanto in vitro, pelo método de coprocultura quantitativa, quanto in vivo, por meio do teste de redução no número de ovos de nematóides nas fezes dos hospedeiros. No teste in vitro, o hidrolato nas concentrações de 40%, 60% e 80% e 100% apresentou porcentagem de eficácia de 91,88%, 94,15%, 98,40% e 100%, respectivamente, mostrando atividade ovicida significativa sobre nematóides gastrintestinais em bezerras. Entretanto, os resultados do teste in vivo mostraram ausência de atividade anti-helmíntica do hidrolato de M. villosa na dose de 0,1ml kg dia-1, nos animais tratados

Action of Heterorhabditis indica (Rhabditida: Heterorhabditidae) strain LPP1 on the reproductive biology of engorged females of Rhipicephalus microplus (Acari: Ixodidae)

AbstractThe aim of this study was to evaluate the effect of different concentrations of the entomopathogenic nematode (EPN) Heterorhabditis indica, LPP1, on the reproductive biology of engorged females of Rhipicephalus microplus. For this purpose, 240 females were divided into eight groups with statistically similar weights (p>0.05). Each group was divided into six subgroups with five females distributed in Petri dishes and exposed to concentrations of 0, 375, 750, 1500, 3000, 6000, 12,000 and 24,000 EPNs/dish. The following biological parameters were evaluated: egg mass weight (mg), egg production index (%EPI), hatching percentage (%) and percentage of control. The action of the nematodes resulted in a significant reduction (p<0.05) in egg mass weight, hatching percentage and EPI in all treatments groups. The percentage of control in all groups was above 97%, reaching 100% at concentrations of 3000 and 12,000 EPNs/female. Comparison of these results with those reported in other articles evaluating the in vitro pathogenicity of different EPN species against R. microplus shows that under laboratory conditions H. indica LPP1 is the one of most virulent species

Genome wide scan for quantitative trait loci affecting tick resistance in cattle (Bos taurus × Bos indicus)

<p><b>Abstract</b></p> <p><b>Background</b></p> <p>In tropical countries, losses caused by bovine tick <it>Rhipicephalus (Boophilus) microplus</it> infestation have a tremendous economic impact on cattle production systems. Genetic variation between <it>Bos taurus</it> and <it>Bos indicus</it> to tick resistance and molecular biology tools might allow for the identification of molecular markers linked to resistance traits that could be used as an auxiliary tool in selection programs. The objective of this work was to identify QTL associated with tick resistance/susceptibility in a bovine F2 population derived from the Gyr (<it>Bos indicus</it>) × Holstein (<it>Bos taurus</it>) cross.</p> <p>Results</p> <p>Through a whole genome scan with microsatellite markers, we were able to map six genomic regions associated with bovine tick resistance. For most QTL, we have found that depending on the tick evaluation season (dry and rainy) different sets of genes could be involved in the resistance mechanism. We identified dry season specific QTL on BTA 2 and 10, rainy season specific QTL on BTA 5, 11 and 27. We also found a highly significant genome wide QTL for both dry and rainy seasons in the central region of BTA 23.</p> <p>Conclusions</p> <p>The experimental F2 population derived from Gyr × Holstein cross successfully allowed the identification of six highly significant QTL associated with tick resistance in cattle. QTL located on BTA 23 might be related with the bovine histocompatibility complex. Further investigation of these QTL will help to isolate candidate genes involved with tick resistance in cattle.</p

Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation

Relação entre o peso e o número de larvas e ninfas ingurgitadas e entre o período de ingurgitamento ninfal e o sexo dos adultos de Haemaphysalis leporispalustris (Packard, 1869) (Acari, Ixodidae) em condições experimentais

The possibility of adopting a pattern for the conversion of weight in number of larvae and engorged nymphs of Haemaphysalis leporispalustris (Packard, 1869) was evaluated. The material studied was kept in a chamber regulated at 27 ± 1°C and UR ³ 80% and fed on rabbits. The conversion of weight in number of engorged larvae (50 engorged larvae varying from 14,15 to 16,08 mg) should be adopted only in experiments which do not require precision owing to the occurrence of significant differences between the groups of 50 engorged larvae according to the rabbit used for the engorgement. The average weight of the 50 engorged nymphs was 73,44 ± 5,30 mg, being this a reliable parameter as there has been no variation among the recovery days nor among the hosts used. There was an influence of the engorgement period on the proportion of males and females obtained at each day of recovery, but the weight average of all engorged nymphs during the infestation period did not influence on this proportion. Although there has been no significant difference among the average weights of the 50 engorged nymphs according to the day of collection, it was observed that there was a greater efficiency in the engorgement of individuals which became males as they got loose more precociously than those which turned into females

Heterorhabditis bacteriophora (Rhabditida: Heterorhabditidae) HP88 for biological control of Rhipicephalus microplus (Acari: Ixodidae): The effect of different exposure times of engorged females to the nematodes

AbstractThe aim of this study was to assess the influence of different exposure times of engorged female the Rhipicephalus microplus to infective juveniles of Heterorhabditis bacteriophora isolate HP88. The engorged females were divided into seven groups (six treatments and one control) of 20 ticks each with statistically similar average weights (p>0.05) and exposed to concentrations of 300 nematodes/tick for periods of 3, 6, 12, 24, 48 and 72h. The following biological parameters were monitored: pre-oviposition period; egg mass weight; hatching percentage; and efficacy of treatment. There was no influence of the exposure time on the pre-oviposition period (p>0.05), while there were significant differences (p<0.05) between the groups exposed for 24, 48 and 72h and the control group with respect to the egg mass weight, and 24h for hatching percentage. Treatment efficacy reached 100% after exposure for 48 and 72h. These results demonstrate that infective juveniles of H. bacteriophora HP88, under laboratory conditions, interfere in the majority of the biological parameters of the non-parasitic phase of engorged R. microplus females when the exposure time is greater than or equal to 24h

Comparação entre as técnicas Gordon & Whitlock modificada e Centrífugo Flutuação para diagnóstico de helmintose em bovinos

O presente estudo objetivou verificar o grau de correlação existente entre as técnicas Gordon & Whitlock modificada (GW) e Centrifugo Flutuação (CF) no diagnóstico de endoparasitoses gastrintestinais em bovinos, e elaborar uma tabela com o grau de infecção de helmintos da Superfamília Strongyloidea, medido pelo número de ovos por grama de fezes (OPG) através das duas técnicas. Foram coletadas amostras de fezes, diretamente da ampola retal, de 12 fêmeas, ¾ holandês/zebu, a partir de seis meses de idade, pesando entre 100 a 150 kg, naturalmente parasitadas por nematóides gastrointestinais, na Fazenda Santa Mônica, da Embrapa Gado de Leite, em Valença, RJ, Brasil. As amostras foram coletadas a cada 21 dias, no período de 28 meses. As contagens de OPG foram realizadas no Laboratório de Parasitologia da Embrapa, em Juiz de Fora, MG. A técnica CF detectou 80.81% de amostras positivas, contra 15.17% da técnica GW, demonstrando que a técnica CF é mais sensível que a GW para contagem de OPG, em bovinos. A técnica GW apresentou maior Coeficiente de Variação (CV = 237%) que a CF (CV = 68%). Entretanto, verificou-se concordância significativa entre elas (rho = 0,118), confirmando a existência de uma correlação entre as mesmas. Esta confirmação permitiu a elaboração de uma tabela do grau de infecção por helmintos da Superfamília Strongyloidea baseada nas duas técnicas, que auxiliará na determinação do limiar de tratamento. Dessa forma, a ausência de parâmetros na tomada de decisão para tratamento de helmintose em bovinos, a partir do grau de infecção, considerada a grande desvantagem da técnica CF, foi eliminada

Percepções e atitudes entre produtores de leite em Minas Gerais relacionado a biologia e controle de carrapatos em bovinos

Submitted by Sandra Infurna ([email protected]) on 2018-11-26T18:53:36Z No. of bitstreams: 1 mariaalice_amaral_etal_IOC_2011.pdf: 221095 bytes, checksum: 4c1b247241edb72f4ca0349f48dca198 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2018-11-26T19:03:33Z (GMT) No. of bitstreams: 1 mariaalice_amaral_etal_IOC_2011.pdf: 221095 bytes, checksum: 4c1b247241edb72f4ca0349f48dca198 (MD5)Made available in DSpace on 2018-11-26T19:03:33Z (GMT). No. of bitstreams: 1 mariaalice_amaral_etal_IOC_2011.pdf: 221095 bytes, checksum: 4c1b247241edb72f4ca0349f48dca198 (MD5) Previous issue date: 2011Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Centro de Experimentação Animal. Rio de Janeiro, RJ, Brasil.Universidade Federal de Lavras. Lavras, MG, Brasil.Universidade Federal Rural do Rio de Janeiro. Departamento de Parasitologia. Seropédica, RJ, Brasil.EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária. Embrapa Gado de Leite. Brasil.Universidade Federal de Juiz de Fora. Juiz de Fora, MG, Brasil.EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária. Embrapa Gado de Leite. Brasil.Este estudo teve como objetivo avaliar o conhecimento dos produtores de leite sobre o carrapato dos bovinos e seu controle. Foram entrevistados 93 produtores de leite de Minas Gerais. Estes produtores não tinham informação sobre testes de eficiência de carrapaticidas e controle de carrapatos. Foi testada associação entre a escolaridade e as práticas e conhecimento sobre os carrapatos e constatou-se que 92,3% dos produtores nada sabiam sobre o período não-parasitário. Para 96,4%, o que determinava o momento do tratamento era o grau de infestação de carrapatos; e 93,3% utilizavam bomba-costal para aplicação do carrapaticida. Ao buscar o cruzamento entre as variáveis de biologia e controle com a escolaridade, cooperativismo, tempo de experiência e tamanho do rebanho, verificou-se que a associação linear entre a escolaridade e a efetivação da pré-diluição no preparo de banhos carrapaticidas. Esses dados demonstraram a necessidade de instrução dos produtores em relação à biologia e ao controle do Rhipicephalus (Boophilus) microplus. Conclui-se que a maioria dos produtores de leite de MG desconhece a biologia dos carrapatos e os fatores que influenciam as escolhas do carrapaticida, o que dificulta a implementação do controle estratégico e que a escolaridade não está relacionada a um controle mais eficiente dos carrapatos nas propriedades.This study evaluates milk producers’ knowledge regarding cattle ticks and practices for controlling them. Ninetythree dairymen in Minas Gerais were interviewed. These producers had no information regarding acaricide efficiency tests. To analyze the information, open responses were categorized through “content analysis”, and descriptive analysis consisting of extracting the profile highlighted by the highest frequencies. The association between schooling level and knowledge was tested by means of chi-square trend tests. It was observed that 92.3% had no knowledge of the nonparasitic period. For 96.4%, what determined the time to apply treatment was the degree of tick infestation; 93.3% used spray guns to apply the acaricide. In seeking to cross-correlate the biological and control variables with education, cooperative action, length of experience and herd size, it was found that there was a linear association between schooling level and implementation of acaricide solution preparation. The other factors didn’t show any significant association. These data demonstrated the need to instruct the producers in relation to the biology and control of Rhipicephalus (Boophilus) microplus. It was concluded that the majority of milk producers were unaware of cattle tick biology and the factors that influence choosing an acaricide, which makes it difficult to implement strategic control

Streptococcus mutans Can Modulate Biofilm Formation and Attenuate the Virulence of Candida albicans.

Streptococcus mutans and Candida albicans are found together in the oral biofilms on dental surfaces, but little is known about the ecological interactions between these species. Here, we studied the effects of S. mutans UA159 on the growth and pathogencity of C. albicans. Initially, the effects of S. mutans on the biofilm formation and morphogenesis of C. albicans were tested in vitro. Next, we investigate the influence of S. mutans on pathogenicity of C. albicans using in vivo host models, in which the experimental candidiasis was induced in G. mellonella larvae and analyzed by survival curves, C. albicans count in hemolymph, and quantification of hyphae in the host tissues. In all the tests, we evaluated the direct effects of S. mutans cells, as well as the indirect effects of the subproducts secreted by this microorganism using a bacterial culture filtrate. The in vitro analysis showed that S. mutans cells favored biofilm formation by C. albicans. However, a reduction in biofilm viable cells and inhibition of hyphal growth was observed when C. albicans was in contact with the S. mutans culture filtrate. In the in vivo study, injection of S. mutans cells or S. mutans culture filtrate into G. mellonella larvae infected with C. albicans increased the survival of these animals. Furthermore, a reduction in hyphal formation was observed in larval tissues when C. albicans was associated with S. mutans culture filtrate. These findings suggest that S. mutans can secrete subproducts capable to inhibit the biofilm formation, morphogenesis and pathogenicity of C. albicans, attenuating the experimental candidiasis in G. mellonella model