Publications by authors named "Rubens D Melo-Junior"

This study compared selective control versus strategic control against Rhipicephalus (Boophilus) microplus, under conditions of a real dairy farm. Strategic control requires that all animals be treated with acaricide at regular pre-determined intervals. Selective control only requires treatment of infested animals and only when they are at or above a pre-determined threshold.

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Article Synopsis
  • The study examined the susceptibility of taurine and zebuine cattle to the cattle tick Rhipicephalus microplus, focusing on tick population dynamics within the same herd over two experiments.
  • In the first experiment, researchers analyzed tick burdens in various age groups of cattle, noting that nursing calves reared in groups had higher tick burdens compared to those raised individually and that tick peaks occurred more frequently in weaning calves and lactating cows.
  • The second experiment involved infesting cattle of different ages with tick larvae to measure how many fully engorged females detachment occurred, with the results indicating age and previous tick exposure affected tick burden and treatment needs.
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It was investigated how many cattle become infected with Trypanosoma vivax by subcutaneous (SC), intramuscular (IM) and intravenous (IV) routes, using the same syringe and needle from an animal with acute T. vivax infection. Besides, the T.

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Background: A point-of-care device that can provide immediate and reliable hemoglobin (Hb) concentrations and packed cell volumes (PCVs) would be useful in veterinary medicine.

Objectives: We aimed to compare the use of a human device (Mission Plus; MP) with a gold standard (GS) method for measuring Hb concentrations and PCVs in cattle blood.

Methods: Blood samples from clinically healthy cattle (n = 122) were collected with or without an anticoagulant (K EDTA).

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Trypanosoma vivax causes bovine trypanosomosis in cattle and resulting in economic losses to farmers. In Brazil, shared contaminated materials is the main transmission pathway. To evaluate the effectiveness of different disinfectants for T.

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Eimeria spp. infections cause mortality, reduced well-being, and substantial economic losses implications for cattle production worldwide. The present work followed up the excretion of Eimeria spp.

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The present study evaluated over two years the seasonal dynamics of Rhipicephalus microplus in a Cerrado biome of midwestern Brazil (Goiânia, Goiás) and correlated the current climatic conditions (environmental temperature, insolation, rainfall, relative humitidy and saturation deficit of the atmosphere) of this site with 30 years ago. In addition, the data collected in the present research were compared with climatic conditions data and R. microplus population dynamics conducted by our group in other regions (Formiga, Minas Gerais and Jaboticabal, São Paulo) within the same biome.

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The objective of this study was to evaluate two different gastrointestinal nematode treatment regimens. Fecal egg counts (FECs), proportion of nematode genera, weight gain, body condition score and reproductive indices (estrous cyclicity, conception and pregnancy rates) were evaluated in yearling heifers after imposing two treatment regimens for gastrointestinal nematodes: T1 = 306 calves treated in May and November with 3.5 % doramectin (700 μg/kg) and August (Aug) with saline solution; and T2 = 307 calves treated in May with 3.

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Rhipicephalus microplus is the most significant tick of livestock and its control is particularly challenging due to its resistance to commercial acaricides. Pasture rotation is considered a management strategy that could help control R. microplus, however, the literature only contemplates mathematical models and little is known about the effects of this practice in the field.

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Rhipicephalus (Boophilus) microplus is the most important livestock tick, causing economical losses especially in tropical and subtropical regions. Pour-on formulations using synthetic chemicals, remain the most farmer friendly conventional form of tick control method. Misuse of acaricides can lead to the emergence of resistance, residual chemicals in animal products, the poisoning of vertebrates and environment contamination.

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