RESUMO

The chemoprotection of "buriti" Mauritia flexuosa (inclusion in diet: 0-control group; 1.25; 2.50; 5.00; and 10.00% W/W) to Litopenaeus vannamei postlarvae (PL) exposed to ammonia or nitrite was in-vestigated. Analyzed variables include antioxidant (ACAP) and oxidative damage (TBARS) responses and levels of total carotenoids. The results indicated that there was no significant difference (p >0.05) in zootechnical variables between diets. The PL carotenoid content (R2 = 0.86), ACAP (R2 = 0.78), and TBARS (R2 = 0.91) showed a dose-dependent relationship with the inclusion levels of "buriti"(p <0.05). After 43 days, juvenile shrimps were exposed for 96 h to ammonia (0.48 mg NH3-N L-1) or nitrite (40 mg NO3 L-1). Higher scavenging activity against peroxyl radicals was observed in PL fed with 2.50 and 5.00% of "buriti" (ammonia exposure), or 5.00 and 10.00% (nitrite exposure) of "buriti" inclusion. Content of reduced glutathione was higher in shrimps exposed to ammonia and fed with 10.00% of "buriti". Lipid peroxidation levels were lower in shrimps exposed to ammonia or nitrite and previously fed with inclusion higher than 2.50% of "buriti". The increased scavenging activity and lower lipid peroxidation in ammonia or nitrite-exposed organisms and previously supplemented with "buriti" point to a hormetic response that increases the resilience of L. vannamei to cope with nitroge-nous compounds, pointing to the use of this fruit as a chemoprotectant agent.

Foi avaliada a quimioproteção do "buriti" Mauritia flexuosa (inclusão na dieta: 0-grupo controle; 1,25; 2,50; 5,00; e 10,00% P/P) em pós-larvas (PL) de Litopenaeus vannamei expostas à amônia ou nitrito. As variáveis analisadas incluíram respostas antioxidantes (ACAP) e de dano oxidativo (TBARS) e te-ores de carotenoides totais. Os resultados obtidos indicaram que não houve diferenças significativas (p >0,05) nas variáveis zootécnicas entre as dietas. O conteúdo de carotenoides nas PL (R2 = 0,86), ACAP (R2 = 0,78), e TBARS (R2 = 0,91) mostraram um relação dose-resposta com os níveis de inclusão de "buriti"(p <0,05). Após 43 días, os camarões juvenis foram expostos por 96 h à amônia (0,48 mg NH3-N L-1) ou à nitrito (40 mg NO3 L-1). Uma elevada capacidade antioxidante contra radicais peroxil foi observada em PL alimentadas 2,50 e 5,00% de "buriti" (exposição à amônia), ou 5,00 e 10,00 % (exposição à nitrito) de inclusão de "buriti". O conteúdo de glutationa reduzida foi superior em camarões expostos à amônia e alimentados com 10.00% de "buriti". Os níveis de peroxidação lipídica foram inferiores em camarões expostos à amônia ou nitrito e previamente alimentados com níveis de inclusão de buriti superiores a 2,50%. O aumento de capacidade antioxidante e redução da peroxidação lipídica nos organismos expostos à amônia ou nitrito que previamente foram suplementados com "buriti" sugere uma resposta hormética, incrementando a resiliência de L. vannamei frente a compos-tos nitrogenados, recomendando o uso deste fruto como agente quimioprotetor.

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RESUMO

Cattle tick fever (CTF) causes significant economic losses in the livestock sector. The pathogenic action of the hemoparasites is associated with anemia, weight loss, abortion and reduced productivity, which result with animal death. Programs to prevent CTF involve several procedures, including immunization, chemoprophylaxis and use of ectoparasiticides, together with the vector control in the environment. The objective of this study was to report an acute outbreak of CTF in a group of 157 Hereford cattle from a farm without presence of the vector, that were moved to a farm in the same state with a high tick infestation (Rhipicephalus microplus). On the day before the transportation, the animals received a chemoprophylaxis with imidocarb dipropionate (3 mg/kg, SC), which was repeated 21 days after the first application. After 42 days, some animals showed signs compatible with CTF, which was confirmed through clinical examination, necropsy, histopathological and hemoparasitological analyses. The morbidity rate was 37.6% and the mortality rate was 24.8%. Calves that were recently weaned were the group most affected with the tick fever, morbidity (100% and mortality (73%). Chemoprophylaxis in association with use of ectoparasiticides was not sufficient to control the outbreak of the disease.

Assuntos

RESUMO

Cattle tick fever (CTF) causes significant economic losses in the livestock sector. The pathogenic action of the hemoparasites is associated with anemia, weight loss, abortion and reduced productivity, which result with animal death. Programs to prevent CTF involve several procedures, including immunization, chemoprophylaxis and use of ectoparasiticides, together with the vector control in the environment. The objective of this study was to report an acute outbreak of CTF in a group of 157 Hereford cattle from a farm without presence of the vector, that were moved to a farm in the same state with a high tick infestation (Rhipicephalus microplus). On the day before the transportation, the animals received a chemoprophylaxis with imidocarb dipropionate (3 mg/kg, SC), which was repeated 21 days after the first application. After 42 days, some animals showed signs compatible with CTF, which was confirmed through clinical examination, necropsy, histopathological and hemoparasitological analyses. The morbidity rate was 37.6% and the mortality rate was 24.8%. Calves that were recently weaned were the group most affected with the tick fever, morbidity (100% and mortality (73%). Chemoprophylaxis in association with use of ectoparasiticides was not sufficient to control the outbreak of the disease.(AU)

A tristeza parasitária bovina (TPB) gera importantes perdas econômicas na bovinocultura mundial. A ação patogênica dos hemoparasitas resulta em anemia, perda de peso, abortos e diminuição da produtividade, culminando, muitas vezes, em óbito dos animais. Um programa de prevenção para TPB necessita de medidas integradas, como a imunização, quimioprofilaxia e utilização de ectoparasiticidas, em conjunto com ações que visem ao controle ambiental dos vetores. Este artigo tem em vista o relato de um surto de TPB em uma fazenda de produção de bovinos de corte e com alta infestação do carrapato (Rhipicephalus microplus). A fazenda adquiriu 157 animais puros de origem, da raça Hereford, proveniente de uma fazenda sem presença do vetor. No dia anterior ao transporte, os animais receberam quimioprofilaxia com dipropionato de imidocarb (3mg/Kg/SC), repetindo-se 21 dias após a primeira aplicação. Aos 42 dias, alguns bezerros manifestaram sinais clínicos compatíveis com TPB, sendo confirmado pelo exame clínico, necropsia, análises histopatológicas e hemoparasitológicas. A morbidade foi de 37,6% (59/157), e a letalidade de 24,8% (39/157). A categoria de bezerros recém desmamados foi a mais acometida, com morbidade de 100% (52/52) e letalidade de 73% (38/52). A quimioprofilaxia associada à utilização de ectoparasiticidas foram insuficientes para evitar a ocorrência do surto da enfermidade.(AU)

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RESUMO

Abstract Cattle tick fever (CTF) causes significant economic losses in the livestock sector. The pathogenic action of the hemoparasites is associated with anemia, weight loss, abortion and reduced productivity, which result with animal death. Programs to prevent CTF involve several procedures, including immunization, chemoprophylaxis and use of ectoparasiticides, together with the vector control in the environment. The objective of this study was to report an acute outbreak of CTF in a group of 157 Hereford cattle from a farm without presence of the vector, that were moved to a farm in the same state with a high tick infestation (Rhipicephalus microplus). On the day before the transportation, the animals received a chemoprophylaxis with imidocarb dipropionate (3 mg/kg, SC), which was repeated 21 days after the first application. After 42 days, some animals showed signs compatible with CTF, which was confirmed through clinical examination, necropsy, histopathological and hemoparasitological analyses. The morbidity rate was 37.6% and the mortality rate was 24.8%. Calves that were recently weaned were the group most affected with the tick fever, morbidity (100% and mortality (73%). Chemoprophylaxis in association with use of ectoparasiticides was not sufficient to control the outbreak of the disease.

Resumo A "tristeza parasitária bovina" (TPB) gera importantes perdas econômicas na bovinocultura mundial. A ação patogênica dos hemoparasitas resulta em anemia, perda de peso, abortos e diminuição da produtividade, culminando, muitas vezes, em óbito dos animais. Um programa de prevenção para TPB necessita de medidas integradas, como a imunização, quimioprofilaxia e utilização de ectoparasiticidas, em conjunto com ações que visem ao controle ambiental dos vetores. Este artigo tem em vista o relato de um surto de TPB em uma fazenda de produção de bovinos de corte e com alta infestação do carrapato (Rhipicephalus microplus). A fazenda adquiriu 157 animais puros de origem, da raça Hereford, proveniente de uma fazenda sem presença do vetor. No dia anterior ao transporte, os animais receberam quimioprofilaxia com dipropionato de imidocarb (3mg/Kg/SC), repetindo-se 21 dias após a primeira aplicação. Aos 42 dias, alguns bezerros manifestaram sinais clínicos compatíveis com TPB, sendo confirmado pelo exame clínico, necropsia, análises histopatológicas e hemoparasitológicas. A morbidade foi de 37,6% (59/157), e a letalidade de 24,8% (39/157). A categoria de bezerros recém desmamados foi a mais acometida, com morbidade de 100% (52/52) e letalidade de 73% (38/52). A quimioprofilaxia associada à utilização de ectoparasiticidas foram insuficientes para evitar a ocorrência do surto da enfermidade.

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The skin secretion from toads of the Bufonidae family has great potential in the search for new active compounds to be used as drug candidates in treating some diseases, among them cancer. In this context, this study aimed to evaluate the cytotoxic and antimutagenic activity of the parotoid gland secretion extracts of Rhinella marina and Rhaebo guttatus, as well as biochemically analyze transaminases and serum creatinine for liver and renal damage, respectively. Cytotoxicity was performed by the colorimetric method based on MTT (3- [4, 5-dimethyl-2-thiazolyl]-2, 5-diphenyl-2H-tetrazolium bromide) with different concentrations of the extracts in Walker or splenic tumor cell cultures from rats and mice. The micronucleus test was performed with male Swiss mice treated orally with the extracts for 15 days, and then intraperitoneally with N-ethyl-N-nitrosurea (50 mg kg-1). Micronucleated polychromatic erythrocytes (MNPCE) were evaluated in bone marrow. The extracts showed cytotoxic activity in the evaluated cells. There was a significant reduction in the frequency of MNPCE (R. marina = 56% and R. guttatus = 75%, p < 0.001), indicating antimutagenic potential of the extracts. The groups treated only with extract showed an increase in MNPCE frequency, evidencing mutagenic potential. Biochemical analyzes showed no significant difference between treatments. Thus, under our experimental conditions, the extracts of R. marina and R. guttatus skin secretions presented chemopreventive potential for cancer. (AU)

A secreção cutânea de anuros da família Bufonidae tem grande potencial na busca de novos compostos ativos para utilização como fármacos candidatos no tratamento de algumas doenças, entre elas o câncer. Neste contexto, este estudo teve como objetivo avaliar a atividade citotóxica e antimutagênica dos extratos da secreção da glândula parótida de Rhinella marina e Rhaebo guttatus, bem como a análise bioquímica de transaminases e creatinina séricas, para avaliar dano hepático e renal, respectivamente. A avaliação de citotoxicidade foi realizada pelo método colorimétrico baseado no MTT (3-[4, 5-dimethyl-2-thiazolyl]-2, 5-diphenyl-2H-tetrazolium bromide), com diferentes concentrações dos extratos em culturas de células do Tumor de Walker ou células esplênicas de rato e camundongo. O teste do micronúcleo foi realizado com camundongos Swiss machos que receberam tratamento oral com os extratos durante 15 dias, seguido de tratamento intraperitoneal com N-etil-N-nitrosuréia (50 mg kg-1). A frequência de eritrócitos policromáticos micronucleados (PCEMN) foi determinada em medula óssea. Os extratos apresentaram ação citotóxica nas células avaliadas. Houve uma redução significativa na frequência de PCEMN (R. marina = 56% e R. guttatus = 75%, p < 0,001), observando-se um potencial antimutagênico dos extratos. Os grupos tratados somente com os extratos apresentaram um aumento na frequência de PCEMNs, evidenciando um potencial mutagênico. As análises bioquímicas não apresentaram diferença significativa entre os tratamentos. Assim, nas condições experimentais testadas, as secreções cutâneas de R. marina e R. guttatus apresentaram potencial quimiopreventivo para câncer.(AU)

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In the present study, 87 Aberdeen Angus calves were used to assess the effects of low dose, agent-specific drugs on weight gain after a babesiosis and anaplasmosis outbreak. All animals were weighed on weaning (day 34) and again on day zero, with a mean (on day zero) of 223.46 Kg and an average individual daily weight gain (ADG) of 0.258 Kg. The animals were then separated in three groups: G1 was composed of 37 calves with below average ADG; G2 was composed of 35 animals with below average ADG; and G3 was composed of 15 animals with above average ADG. On day zero animals in G1 were treated with 1.17 mg Kg-1 of diminazene diaceturate and 6.7 mg Kg-1 of oxytetracycline; those in G2 were treated with 1.2 mg Kg-1 of imidocarb dipropionate; and those in G3 were not treated. The animals were then monitored daily for the onset of disease, and on days 15 and 34 they were weighed and had their blood harvested. Animals in G1 had the better overall ADG (0.613 Kg day-1) (P 0.05), with no clinical cases during the experiment. The performance in G2 was moderate, not differing from either G1 or G3 (mean ADG = 0.528 Kg day-1), however, this group had two clinical cases of anaplasmosis during the experiment. Animals in G3 had the worst performance, considering ADG (0.343 Kg day-1). When total weight gain per animal is compared for the study period (35 days), those in G1 gained an average...(AU)

No presente estudo foram utilizados novilhos da raça Aberdeen Angus remanescentes de um de surto de babesiose e anaplasmose, expostos a infestações por carrapatos Rhipicephalus (Boophilus) microplus. No dia zero, o lote de 87 novilhos pesando em média 223,46 Kg, apresentava GMD de peso vivo de 0,258 Kg por dia nos últimos 34 dias. O lote foi dividido em 3 grupos: G1, 37 novilhos com GMD abaixo da média; G2, 35 novilhos com GMD abaixo da média; G3, 15 novilhos com GMD acima da média geral do lote. Os novilhos do G1 foram submetidos à quimioprofilaxia com uso de 1,17 mg Kg-1 de diaceturato de diminazeno e 6,7 mg Kg-1 de oxitetraciclina. Os novilhos do G2 foram submetidos à quimioprofilaxia com o uso de 1,2 mg Kg-1 de dipropionato de imidocarb. Os animais do G3 não foram medicados. O G1 obteve o melhor desempenho de ganho de peso no período (0,613 Kg dia-1) (P 0,05) e não apresentou nenhum caso clínico da doença durante o experimento. O protocolo quimioprofilático do G2 teve desempenho mediano, sem diferença dos demais grupos (0,528 Kg dia-1) e o G3 teve o pior desempenho (0,343 Kg dia-1), porém ocorreram 2 quadros clínicos de anaplasmose no final do experimento no G2. Na comparação do desempenho no ganho de peso total por animal no período, o G3 (Controle) obteve 11,667 Kg, O G2 obteve 17,957 Kg e o G1 obteve 20,851 Kg. O protocolo quimioprofilático a base de diaceturato de...(AU)

Assuntos

RESUMO

In the present study, 87 Aberdeen Angus calves were used to assess the effects of low dose, agent-specific drugs on weight gain after a babesiosis and anaplasmosis outbreak. All animals were weighed on weaning (day 34) and again on day zero, with a mean (on day zero) of 223.46 Kg and an average individual daily weight gain (ADG) of 0.258 Kg. The animals were then separated in three groups: G1 was composed of 37 calves with below average ADG; G2 was composed of 35 animals with below average ADG; and G3 was composed of 15 animals with above average ADG. On day zero animals in G1 were treated with 1.17 mg Kg-1 of diminazene diaceturate and 6.7 mg Kg-1 of oxytetracycline; those in G2 were treated with 1.2 mg Kg-1 of imidocarb dipropionate; and those in G3 were not treated. The animals were then monitored daily for the onset of disease, and on days 15 and 34 they were weighed and had their blood harvested. Animals in G1 had the better overall ADG (0.613 Kg day-1) (P 0.05), with no clinical cases during the experiment. The performance in G2 was moderate, not differing from either G1 or G3 (mean ADG = 0.528 Kg day-1), however, this group had two clinical cases of anaplasmosis during the experiment. Animals in G3 had the worst performance, considering ADG (0.343 Kg day-1). When total weight gain per animal is compared for the study period (35 days), those in G1 gained an average...

No presente estudo foram utilizados novilhos da raça Aberdeen Angus remanescentes de um de surto de babesiose e anaplasmose, expostos a infestações por carrapatos Rhipicephalus (Boophilus) microplus. No dia zero, o lote de 87 novilhos pesando em média 223,46 Kg, apresentava GMD de peso vivo de 0,258 Kg por dia nos últimos 34 dias. O lote foi dividido em 3 grupos: G1, 37 novilhos com GMD abaixo da média; G2, 35 novilhos com GMD abaixo da média; G3, 15 novilhos com GMD acima da média geral do lote. Os novilhos do G1 foram submetidos à quimioprofilaxia com uso de 1,17 mg Kg-1 de diaceturato de diminazeno e 6,7 mg Kg-1 de oxitetraciclina. Os novilhos do G2 foram submetidos à quimioprofilaxia com o uso de 1,2 mg Kg-1 de dipropionato de imidocarb. Os animais do G3 não foram medicados. O G1 obteve o melhor desempenho de ganho de peso no período (0,613 Kg dia-1) (P 0,05) e não apresentou nenhum caso clínico da doença durante o experimento. O protocolo quimioprofilático do G2 teve desempenho mediano, sem diferença dos demais grupos (0,528 Kg dia-1) e o G3 teve o pior desempenho (0,343 Kg dia-1), porém ocorreram 2 quadros clínicos de anaplasmose no final do experimento no G2. Na comparação do desempenho no ganho de peso total por animal no período, o G3 (Controle) obteve 11,667 Kg, O G2 obteve 17,957 Kg e o G1 obteve 20,851 Kg. O protocolo quimioprofilático a base de diaceturato de...

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