Publications by authors named "Marcio D Rabelo"
Article Synopsis
- - Haemonchus contortus is a harmful worm that causes anemia in sheep, making early diagnosis crucial for effective treatment and reducing the need for antiparasitic drugs.
- - This study utilized near-infrared spectroscopy (NIRS) to predict packed cell volume (PCV) values and develop models for diagnosing H. contortus infections based on PCV, fecal egg counts, and daily weight gain.
- - Results showed that the NIRS model effectively predicted PCV with a high correlation, while the classification model achieved 93.33% sensitivity and 82.18% accuracy, outperforming traditional methods, indicating its potential for quick diagnosis of infections in sheep.
Chemical Composition and In vitro Anthelmintic Activity of Extracts of Tagetes patula Against a Multidrug-Resistant Isolate of Haemonchus contortus.
Chem Biodivers
February 2018
Sheep breeding has suffered economic losses due to parasitism by gastrointestinal nematodes, particularly Haemonchus contortus. The use of natural products, specifically Tagetes patula, has been suggested as an alternative method of combatting this issue. Chemical analyses of the extracts of this species described in the literature report the presence of important classes of secondary metabolites such as thiophenes, flavonoids, alkaloids, and benzofurans, some of which were identified and isolated in this study.
View Article and Find Full Text PDFThe use of silvopastoral systems (SPS) can be a good alternative to reduce the environmental impacts of livestock breeding in Brazil. One of the reasons for its scarce adoption is the lack of information on health and productivity of cattle raised under these conditions. The experiment reported here was designed to compare the infestation by external parasites - the cattle tick (Rhipicephalus microplus), horn fly (Haematobia irritans), and larvae of the botfly (Dermatobia hominis) - in beef cattle raised in a SPS and a conventional pasture system (CPS), evaluated for 24 months.
View Article and Find Full Text PDFNeither quantification by qPCR nor quantitative Elisa can be used to discriminate Angus cattle for resistance/susceptibility to Babesia bovis.
Ticks Tick Borne Dis
March 2017
With the aim of finding quantitative phenotypic traits that can be used to discriminate the levels of resistance/susceptibility to Babesia bovis, we estimated the repeatability and correlation between the level of infection, determined by the number of copies of a fragment of the gene that encodes cytochrome B (NC mt-cyB) of B. bovis, and the levels of the anti-B. bovis antibodies, in blood samples collected from 51 Angus cattle on two different occasions.
View Article and Find Full Text PDFThe development of resistance to anthelmintics has prompted research into alternative methods of controlling intestinal nematodes in ruminants. This study aimed to assess the activity of Ananas comosus on Haemonchus contortus in Santa Inês sheep. The aqueous extract of pineapple skin (AEPS), bromelain from pineapple stems (B4882) and residue from pineapple processing was evaluated in in vitro and in vivo tests.
View Article and Find Full Text PDFArticle Synopsis
- Chemical methods to control cattle ticks are becoming ineffective due to resistance, prompting the study of natural alternatives like pineapple extract.
- The aqueous extract of pineapple skin (AEPS) and bromelain were tested in various concentrations on engorged females and larvae of Rhipicephalus (Boophilus) microplus, revealing some effectiveness in reducing survival and oviposition of females.
- While the most effective concentrations for engorged females showed some impact, neither extract was effective against the larvae, indicating the need for further research to optimize these natural compounds against cattle ticks.