scholarly journals Influence of selective treatment on Haematobia irritans infestation of untreated cattle

2019 ◽  
Author(s):  
Cecilia Miraballes ◽  
Henrik Stryhn ◽  
Antonio Thadeu M. Barros ◽  
Martin Lucas ◽  
Luísa Nogueira Domingues ◽  
...  

AbstractTo reduce the use of insecticide treatments against Haematobia irritans we evaluated the impact of treating 15% of the bovines, with the greatest number of flies including bulls, with 40% diazinon ear tags, on the infestation of untreated cows. Horn fly susceptibility to diazinon was measured before and after treatment, and peaks of infestation were recorded. Three groups of Bradford bovines were evaluated: Group 1 (control untreated), Group 2 (15% treated) and Group 3 (control 100% treated). Weekly counts of horn flies were performed on the same animals for 78 days. Two peaks of infestation were recorded, and a higher number of horn flies occurred in the untreated control group than in the untreated cows of the selectively treated group throughout the entire period of the study, except for a single week. The horn fly field population was significantly more susceptible to diazinon than the reference susceptible strain both before and after insecticide treatment. In conclusion, treatment of 15% of the most infested animals from a herd, with 40% diazinon ear tags, quickly reduced horn fly infestations of the entire herd and may be a practical approach for horn fly control, reducing costs and chemical use.

1965 ◽  
Vol 45 (1) ◽  
pp. 43-50 ◽  
Author(s):  
M. A. Khan ◽  
J. E. Lawson

Spraying yearlings with 2% Co-Ral in July was 100% effective for systemic control of cattle grubs (Hypoderma spp.). Spraying spring calves with 1% Co-Ral in August was equally effective, and gave better control (P < 0.01) than spraying with 1 or 2% Co-Ral in June or 0.5% Co-Ral in July. Co-Ral sprays were not suitable for horn fly (Haematobia irritans L.) control.Two per cent Sevin sprayed on calves in June or July did not control cattle grubs, and only partially controlled horn flies.Compared with the control group, the average daily gain was higher (P < 0.05) to weaning but lower (P < 0.05) in the feedlot in calves sprayed with 2% Sevin in June. Similarly, it was higher (P < 0.05) from birth to the end of the feedlot period in calves sprayed with 2% Co-Ral in June, but lower (P < 0.05) in calves sprayed with 0.5% Co-Ral in July.Mild toxicosis occurred in five calves sprayed with 2% Co-Ral in June, and subclinical toxicosis in calves sprayed with 1% Co-Ral in August.


2019 ◽  
Author(s):  
Mukund Madhav ◽  
Rhys Parry ◽  
Jess A.T. Morgan ◽  
Peter James ◽  
Sassan Asgari

AbstractThe horn fly, Haematobia irritans irritans, is a hematophagous parasite of livestock distributed throughout Europe, Africa, Asia, and the Americas. Welfare losses on livestock due to horn fly infestation are estimated to cost between USD 1-2.5 billion annually in North America and Brazil. The endosymbiotic bacterium Wolbachia pipientis is a maternally inherited manipulator of reproductive biology in arthropods and naturally infects laboratory colonies of horn flies from Kerrville, USA and Alberta, Canada, but has also been identified in wild-caught samples from Canada, USA, Mexico and Hungary. Reassembly of PacBio long-read and Illumina genomic DNA libraries from the Kerrville H. i. irritans genome project allowed for a complete and circularised 1.3 Mb Wolbachia genome (wHae). Annotation of wHae yielded 1249 coding genes, 34 tRNAs, three rRNAs, and five prophage regions. Comparative genomics and whole genome Bayesian evolutionary analysis of wHae compared to published Wolbachia genomes suggests that wHae is most closely related to and diverged from Wolbachia supergroup A strains known to infect Drosophila spp. Whole-genome synteny analyses between wHae and closely related genomes indicates that wHae has undergone convoluted genome rearrangements while maintaining high nucleotide identity. Comparative analysis of the cytoplasmic incompatibility (CI) genes of wHae suggests two phylogenetically distinct CI loci and acquisition of another CifB homolog from phylogenetically distant supergroup A Wolbachia strains suggesting horizontal acquisition of these loci. The wHae genome provides a resource for future examination of the impact Wolbachia may have in both biocontrol and potential insecticide resistance of horn flies.ImportanceHorn flies, Haematobia irritans, are obligate hematophagous parasites of cattle having significant effects on production and animal welfare. Control of horn flies mainly relies on the use of insecticides, but issues with resistance have increased interest in development of alternative means of control. Wolbachia pipientis is an endosymbiont bacterium known to have a range of effects on host reproduction such as induction of cytoplasmic incompatibility, feminization, male killing, and also impacts on vector transmission. These characteristics of Wolbachia have been exploited in biological control approaches for a range of insect pests. Here we report the assembly and annotation of the circular genome of the Wolbachia strain of the Kerrickville, USA horn fly (wHae). Annotation of wHae suggests its unique features including the horizontal acquisition of additional transcriptionally active cytoplasmic incompatibility loci. This study will provide the foundation for future Wolbachia-induced biological effect studies for control of horn flies.


1982 ◽  
Vol 62 (2) ◽  
pp. 567-573 ◽  
Author(s):  
W. O. HAUFE

An experiment was conducted on a ranch to evaluate the efficacy of polyvinyl ear tags impregnated with fenvalerate to control horn flies and to improve growth of steers on range. An experimental tag, weighing 10.8 g and containing 7.2% fenvalerate by weight, was attached to each ear of yearling steers when they were moved to summer range in May. The tags were evaluated in combination with zeranol implanted as a growth stimulant during a 115-day grazing period. Release of fenvalerate from the tags kept a treated group of animals completely fly-free. At the end of the experiment, liveweight gain due to slow release of fenvalerate was increased by 18.5% for implanted and 17.7% for unimplanted animals. Increases due to zeranol implants were 7.1% for animals protected and 6.3% for those unprotected from horn flies. No statistical evidence was found for interaction between responses to the impregnated ear tags and growth stimulator implants in increasing the rate of gain in weight of the steers on pasture. The results of this experiment under ranching conditions corresponded closely with basic measurements on the impact of horn flies on productivity of cattle in a model for host-parasite regulation. Key words: Cattle, flies, ear tags, Haematobia irritans, fenvalerate


2021 ◽  
pp. 025576142110272
Author(s):  
Oriana Incognito ◽  
Laura Scaccioni ◽  
Giuliana Pinto

A number of studies suggest a link between musical training and both specific and general cognitive abilities, but despite some positive results, there is disagreement about which abilities are improved. This study aims to investigate the effects of a music education program both on a domain-specific competence (meta-musical awareness), and on general domain competences, that is, cognitive abilities (logical-mathematical) and symbolic-linguistic abilities (notational). Twenty 4- to 6-year-old children participated in the research, divided into two groups (experimental and control) and the measures were administered at two different times, before and after a 6-month music program (for the experimental group) and after a sports training program (for the control group). Children performed meta-musical awareness tasks, logical-mathematical tasks, and emergent-alphabetization tasks. Non-parametric statistics show that a music program significantly improves the development of notational skills and meta-musical awareness while not the development of logical-mathematical skills. These results show that a musical program increases children’s meta-musical awareness, and their ability to acquire the notational ability involved in the invented writing of words and numbers. On the contrary, it does not affect the development of logical skills. The results are discussed in terms of transfer of knowledge processes and of specific versus general domain effects of a musical program.


2020 ◽  
Vol 8 (1) ◽  
pp. 209-228
Author(s):  
Layla Parast ◽  
Priscillia Hunt ◽  
Beth Ann Griffin ◽  
David Powell

AbstractIn some applications, researchers using the synthetic control method (SCM) to evaluate the effect of a policy may struggle to determine whether they have identified a “good match” between the control group and treated group. In this paper, we demonstrate the utility of the mean and maximum Absolute Standardized Mean Difference (ASMD) as a test of balance between a synthetic control unit and treated unit, and provide guidance on what constitutes a poor fit when using a synthetic control. We explore and compare other potential metrics using a simulation study. We provide an application of our proposed balance metric to the 2013 Los Angeles (LA) Firearm Study [9]. Using Uniform Crime Report data, we apply the SCM to obtain a counterfactual for the LA firearm-related crime rate based on a weighted combination of control units in a donor pool of cities. We use this counterfactual to estimate the effect of the LA Firearm Study intervention and explore the impact of changing the donor pool and pre-intervention duration period on resulting matches and estimated effects. We demonstrate how decision-making about the quality of a synthetic control can be improved by using ASMD. The mean and max ASMD clearly differentiate between poor matches and good matches. Researchers need better guidance on what is a meaningful imbalance between synthetic control and treated groups. In addition to the use of gap plots, the proposed balance metric can provide an objective way of determining fit.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ádám László Nagy ◽  
Zsolt Tóth ◽  
Tamás Tarjányi ◽  
Nándor Tamás Práger ◽  
Zoltán Lajos Baráth

Abstract Background In this research the biomechanical properties of a bone model was examined. Porcine ribs are used as experimental model. The objective of this research was to investigate and compare the biomechanical properties of the bone model before and after implant placement. Methods The bone samples were divided in three groups, Group 1 where ALL-ON-FOUR protocol was used during pre-drilling and placing the implants, Group 2 where ALL-ON-FOUR protocol was used during pre-drilling, and implants were not placed, and Group 3 consisting of intact bones served as a control group. Static and dynamic loading was applied for examining the model samples. Kruskal–Wallis statistical test and as a post-hoc test Mann–Whitney U test was performed to analyze experimental results. Results According to the results of the static loading, there was no significant difference between the implanted and original ribs, however, the toughness values of the bones decreased largely on account of predrilling the bones. The analysis of dynamic fatigue measurements by Kruskal–Wallis test showed significant differences between the intact and predrilled bones. Conclusion The pre-drilled bone was much weaker in both static and dynamic tests than the natural or implanted specimens. According to the results of the dynamic tests and after a certain loading cycle the implanted samples behaved the same way as the control samples, which suggests that implantation have stabilized the skeletal bone structure.


2019 ◽  
Vol 3 (4) ◽  
pp. 545-552
Author(s):  
Nathalia De Oro ◽  
Maria E Gauthreaux ◽  
Julie Lamoureux ◽  
Joseph Scott

Abstract Background Procalcitonin (PCT) is a biomarker that shows good sensitivity and specificity in identifying septic patients. Methods This study investigated the diagnostic accuracy of PCT in a community hospital setting and how it compared to that of lactic acid. It explored the impact on patient care before and after PCT implementation regarding costs and length of stay. Two comparative groups were analyzed using an exploratory descriptive case–control study with data from a 19-month period after PCT implementation and a retrospective quasi-experimental study using a control group of emergency department patients diagnosed with sepsis using data before PCT implementation. Results Post-procalcitonin implementation samples included 165 cases and pre-procalcitonin implementation sample included 69 cases. From the 165 sepsis cases who had positive blood cultures, PCT had a sensitivity of 89.7%. In comparison, lactic acid's sensitivity at the current cutoff of 18.02 mg/dL (2.0 mmol/L) was 64.9%. There was a 32% decrease in median cost before and after PCT implementation, even with the length of stay remaining at 5 days in both time periods. Conclusions There was a significant decrease after the implementation of PCT in cost of hospitalization compared to costs before implementation. This cost is highly correlated with length of stay; neither the hospital nor the intensive care unit length of stay showed a difference with before and after implementation. There was a positive correlation between lactic acid and PCT values. PCT values had a higher predictive usefulness than the lactic acid values.


2021 ◽  
Author(s):  
Vildan Güngörer ◽  
Mehmet Öztürk ◽  
Mustafa Yasir Özlü ◽  
Şükrü Arslan

ABSTRACT Objectives Long-term therapy with low-dose methotrexate (MTX) is widely used in treatment of rheumatic diseases, in children. The purpose of this study was to evaluate liver elasticity in patients with juvenile idiopathic arthritis (JIA) who received MTX and compare the results with control group. Methods Liver elasticity was evaluated with shear wave elastography (SWE) technique in 25 patients aged 3–17 years who were followed up with JIA and received MTX and compared with 25 healthy controls of the same age and weight. Factors that had an effect on liver elasticity were examined. Results The mean SWE value of patients was 2.64 ± 2.13 m/s and 24.10 ± 18.50 kPa, whereas 1.83 ± 0.16 m/s and 10.09 ± 1.83 kPa in control group. There was a significant difference in liver elasticity in the patient and control groups. When the patients were evaluated as Group 1 (&lt; 1000 mg) and Group 2 (≥ 1000 mg) according to the cumulative MTX dose, no significant difference was obtained. There was positive correlation between liver elasticity and weekly MTX dose and age. Conclusions Our study revealed that liver elasticity significantly decreased in patients who received MTX when compared with the control group. The elastography technique will be understood better over time and used safely in many areas.


2021 ◽  
Vol 12 ◽  
Author(s):  
Matías E. Rodríguez-Rivas ◽  
Adolfo J. Cangas ◽  
Daniela Fuentes-Olavarría

Stigma toward mental disorders is one of today's most pressing global issues. The Covid-19 pandemic has exacerbated the barriers to social inclusion faced by individuals with mental disorders. Concurrently, stigma reduction interventions, especially those aimed at university students, have been more difficult to implement given social distancing and campus closures. As a result, alternative delivery for programs contributing to stigma reduction is required, such as online implementation. This paper reports the results of a controlled study focused on an online multi-component program on reducing stigma toward mental illness that included project-based learning, clinical simulations with standardized patients and E-Contact with real patients. A total of 40 undergraduate students from the Universidad del Desarrollo in Santiago, Chile, participated in the study. They were randomly divided between an intervention and control group. The intervention group participated in the online multi-component program, while the control group participated in an online educational program on cardiovascular health. We assessed the impact of the program by using the validated Spanish-language versions of the Attribution Questionnaire AQ-27 and the Questionnaire on Student Attitudes toward Schizophrenia with both groups, before and after the intervention. In addition, an ad hoc Likert scale ranging from 0 to 5 was used with the intervention group in order to assess the learning strategies implemented. Following the intervention, the participants belonging to the intervention group displayed significantly lower levels of stereotypes, perception of dangerousness, and global score toward people with schizophrenia (p &lt; 0.001). In addition, participants presented lower levels of dangerousness-fear, avoidance, coercion, lack of solidarity, and global score (p &lt; 0.001). The control group displayed no statistically significant differences in the level of stigma before and after the evaluation, for all of the items assessed. Finally, the overall assessment of each of the components of the program was highly positive. In conclusion, the study shows that online programs can contribute to reducing stigma toward mental disorders. The program assessed in this study had a positive impact on all the dimensions of stigma and all of the components of the program itself were positively evaluated by the participants.


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Hong Ding ◽  
Jinglian Shen ◽  
Yang Yang ◽  
Yuqin Che

Signal transducer and activator of transcription factor 3 (STAT3) plays an important role in the proliferation and angiogenesis in human glioma. Previous research indicated that saw palmetto extract markedly inhibited the proliferation of human glioma cells through STAT3 signal pathway. But its effect on tumor metastasis and antiangiogenesis is not clear. This study is to further clear the impact of saw palmetto extract on glioma cell metastasis, antiangiogenesis, and its mechanism. TUNEL assay indicated that the apoptotic cells in the saw palmetto treated group are higher than that in the control group (p<0.05). The apoptosis related protein is detected and the results revealed that saw palmetto extract inhibits the proliferation of human glioma. Meanwhile pSTAT3 is lower in the experimental group and CD34 is also inhibited in the saw palmetto treated group. This means that saw palmetto extract could inhibit the angiogenesis in glioma. We found that saw palmetto extract was an important phytotherapeutic drug against the human glioma through STAT3 signal pathway. Saw palmetto extract may be useful as an adjunctive therapeutic agent for treatment of individuals with glioma and other types of cancer in which STAT3 signaling is activated.


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