Reassessment of the potential economic impact of cattle parasites in Brazil

Grisi, Laerte; Leite, Romário Cerqueira; Martins, João Ricardo; Barros, Antônio Thadeu Medeiros de; Andreotti, Renato; Cançado, Paulo Henrique Duarte; León, Adalberto A Pérez de; Pereira, Jairo Barros; Villela, Humberto Silva

doi:10.1590/s1984-29612014042

Cited by 550 publications

(313 citation statements)

References 22 publications

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“…In Brazil, the productive potential for ruminants that are suitable for animal husbandry is hampered by endoparasitic infections. In the cattle sector, where the country is a world leader in commercial herds, annual losses caused by gastrointestinal parasites are estimated to reach up to $ 7.11 billion (GRISI et al, 2014). Sheep and goats, for which there is a developing production chain in the country, are even more susceptible, and their high mortality rate is a significant deterrent to agribusiness.…”

Section: Introductionmentioning

confidence: 99%

Overview of anthelmintic resistance of gastrointestinal nematodes of small ruminants in Brazil

Salgado

Santos

2016

Rev. Bras. Parasitol. Vet.

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Frequent and inappropriate use of all classes of antiparasitic drugs in small ruminants has led to failures in their effectiveness, culminating in a global problem of anthelmintic resistance. Brazil stands out as one of the world's leaders in publications about anthelmintic resistance, and for having the most numerous reports of this resistance in small ruminants in the Americas. These studies have involved mainly the fecal egg count reduction test (FECRT) and its correlation with field management practices. In vivo effectiveness testing is conducted in areas where livestock is of greater economic significance, e.g., in the South (sheep) and Northeast (goats), or is important for research and economic centers, such as the Southeast (sheep). The most widely studied species is sheep, for which the widest range of drugs is also evaluated. Despite significant advances achieved in molecular research, laboratory analyses should include knowledge about the reality in the field so that they can become feasible for the producer. Moreover, molecular studies can be underpinned by the analysis of field studies, such as the maintenance of antiparasitic effectiveness over time and the mechanisms involved in this process.Keywords: Small ruminants, anthelmintic resistance, sheep, goat, gastrointestinal nematodes. ResumoO uso frequente e inapropriado de todas as classes de antiparasitários em pequenos ruminantes levou a falhas de eficácia, culminando na problemática global de resistência anti-helmíntica. O Brasil destaca-se como sendo um dos pioneiros nas publicações com resistência anti-helmíntica no mundo e por ter o maior número de relatos em pequenos ruminantes na América. Essas pesquisas envolvem principalmente o teste da redução da contagem de ovos nas fezes (TRCOF) e sua correlação com as práticas de manejo utilizadas no campo. Os estudos de testes de eficácia in vivo localizam-se em áreas onde há maior importância dos rebanhos como nas Regiões Sul (ovinos) e Nordeste (caprinos), ou com importância em polos de pesquisa e econômicos, como a região Sudeste (ovinos). Ovina é a espécie mais estudada e com maior gama de drogas avaliadas. Mesmo com grande avanço em pesquisas moleculares, as análises laboratoriais devem envolver o conhecimento da realidade do campo para que possam se tornar viáveis ao produtor. Além disso, a análise dos estudos de campo pode nortear estudos moleculares como, por exemplo, a manutenção da eficácia das drogas ao longo dos anos e os mecanismos envolvidos em tal processo.

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Section: Introductionmentioning

confidence: 99%

Overview of anthelmintic resistance of gastrointestinal nematodes of small ruminants in Brazil

Salgado

Santos

2016

Rev. Bras. Parasitol. Vet.

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“…Infestation of herds with R. (B. ) microplus cause losses estimated at US$3.24 billion per year in Brazil (GRISI et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

New insights from molecular characterization of the tick Rhipicephalus (Boophilus) microplus in Brazil

Csordas

Garcia

Cunha

et al. 2016

Rev. Bras. Parasitol. Vet.

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“…In Brazil, this species is widespread and can be found in all states of the country. Its parasitism among production animals gives rise to significant losses due to weight loss, lower meat and milk production and mortality (Grisi et al 2014). In endemic regions of Brazil, the greatest concentration of cases of myiasis due to C. hominivorax larvae occurs when calves are born and castrated (Lima et al 2004).…”

Section: Introductionmentioning

confidence: 99%

Proteolytic activity of excretory/secretory products of Cochliomyia hominivorax larvae (Diptera: Calliphoridae)

et al. 2016

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The protein profiles and proteolytic activity of the excretory secretory products (E/SP) of the first (L1), second (L2) and third (L3) larval stages of Cochliomyia hominivorax were studied in the laboratory. Analysis on the E/SP protein profile was carried out using polyacrylamide gel containing sodium dodecyl sulfate (SDS-PAGE). The E/SP of each larval stage (L1, L2 and L3) treated with protease inhibitors, containing 30μg, 40μg and 50μg of protein, was applied to the 10% polyacrylamide gel. The proteolytic activity of the crude E/SP was analyzed in gels copolymerized with gelatin and by colorimetric assays using azocasein as a substrate, with the characterization of the proteases using synthetic inhibitors. Different protein profiles were observed for the larval instars, with L1 presenting the most complex profile. Nevertheless, various protein bands were observed that were common to all the larval instars. The E/SP of all the instars showed proteolytic activity on gelatin, evidenced by proteolysis zones, predominantly with apparently higher molecular masses in L1, while for L2 and L3 the proteolysis zones could also be observed in regions with lower masses. Tests with protease inhibitors using gelatin as substrate showed that the E/SP of larvae were mainly composed of serine proteases. Additionally, inhibition was observed in L2 E/SP treated previously with EDTA, an inhibitor of metalloproteases. The assays with azocasein revealed a gradual increase of proteolytic activity on this substrate with larval development progress, with the strongest inhibitions being observed after treatments with 3,4-dichloroisocoumarin (DCI) for E/SP of L1, L2 and L3. These results suggest that C. hominivorax larvae produce different proteases, a fact that can be related to the parasite's vital processes for survival, such as penetration into the host's tissues and nutrition during the larval stage.

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Reassessment of the potential economic impact of cattle parasites in Brazil

Cited by 550 publications

References 22 publications

Overview of anthelmintic resistance of gastrointestinal nematodes of small ruminants in Brazil

Overview of anthelmintic resistance of gastrointestinal nematodes of small ruminants in Brazil

New insights from molecular characterization of the tick Rhipicephalus (Boophilus) microplus in Brazil

Proteolytic activity of excretory/secretory products of Cochliomyia hominivorax larvae (Diptera: Calliphoridae)

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