Plant poisoning containing hydrocyanic acid in cattle in Southern Brazil

Background: Cyanogenic plants accumulate cyanogenic glycosides and release hydrocyanic acid (HCN). In Brazil, therehave been reports of several plants that cause HCN poisoning in animals and lead to a fast death with few clinical signs andlesions on post mortem examination. Some cultivars of Cynodon spp. grasses cause HCN poisoning in cattle in Brazil. Theobjectives of this work were to report the occurrence of deaths by HCN poisoning in cattle as diagnosed by the veterinarypathology laboratory, describe the quantity of HCN in some cultivars of Cynodon spp., as well as, to describe one cultivarof genus Cynodon never reported as poisonous.Materials, Methods & Results: The archives of the Veterinary Pathology Laboratory (LPV) at the Concórdia Campus ofthe Instituto Federal Catarinense (IFC) were reviewed, seeking cases with a diagnosis of hydrocyanic acid poisoning incattle after post mortem examination. The amount of HCN present in some cultivars of the Cynodon genus was quantified due to the high frequency of poisoning cases. From the 1,235 post mortem examinations of cattle 28 (2.27%) werediagnosed with spontaneous hydrocyanic acid poisoning, 17 cases (60.7%) due to ingestion of Prunus sp. or Manihotsp., and 11 cases (39.3%) of Cynodon dactylon ingestion. Most animals were found dead, normally having presented noclinical signs. Macroscopic evaluation mainly showed a severe amount of unchewed and undigested leaves or grass mixedin the ruminal content presenting a bitter almond odor. It was possible to infer that, among cultivars of the Cynodon genus, Florakirk showed the highest levels of HCN compared (P < 0.05) with Star of Puerto Rico, Tifton 68, Tifton 44, andCoast-Cross. Furthermore, Tifton 85 and Jiggs showed undetected levels of HCN...

Plant poisoning containing hydrocyanic acid in cattle in Southern Brazil

Background: Cyanogenic plants accumulate cyanogenic glycosides and release hydrocyanic acid (HCN). In Brazil, therehave been reports of several plants that cause HCN poisoning in animals and lead to a fast death with few clinical signs andlesions on post mortem examination. Some cultivars of Cynodon spp. grasses cause HCN poisoning in cattle in Brazil. Theobjectives of this work were to report the occurrence of deaths by HCN poisoning in cattle as diagnosed by the veterinarypathology laboratory, describe the quantity of HCN in some cultivars of Cynodon spp., as well as, to describe one cultivarof genus Cynodon never reported as poisonous.Materials, Methods & Results: The archives of the Veterinary Pathology Laboratory (LPV) at the Concórdia Campus ofthe Instituto Federal Catarinense (IFC) were reviewed, seeking cases with a diagnosis of hydrocyanic acid poisoning incattle after post mortem examination. The amount of HCN present in some cultivars of the Cynodon genus was quantified due to the high frequency of poisoning cases. From the 1,235 post mortem examinations of cattle 28 (2.27%) werediagnosed with spontaneous hydrocyanic acid poisoning, 17 cases (60.7%) due to ingestion of Prunus sp. or Manihotsp., and 11 cases (39.3%) of Cynodon dactylon ingestion. Most animals were found dead, normally having presented noclinical signs. Macroscopic evaluation mainly showed a severe amount of unchewed and undigested leaves or grass mixedin the ruminal content presenting a bitter almond odor. It was possible to infer that, among cultivars of the Cynodon genus, Florakirk showed the highest levels of HCN compared (P < 0.05) with Star of Puerto Rico, Tifton 68, Tifton 44, andCoast-Cross. Furthermore, Tifton 85 and Jiggs showed undetected levels of HCN...(AU)

Corn and alexandergrass intercropping system: influences of herbicide management on grain and forage yield / Sistema consorciado de milho e papuã: influência do manejo comherbicidas no rendimento de grãos e forragem

In Southern Brazil, intercropping system between corn and Urochloa is an interesting way to improve soil cover and animal feed after corn harvesting. This study was carried out with the objective to evaluate the effect of herbicides and its doses on corn and Alexandergrass (Urochloa plantaginea) yield, in an intercropped system. The experiment was arranged in a randomized block design, with four replications in a factorial scheme. First factor was composed of four herbicide associations: (1) Atrazine + Oil; (2) Atrazine + Simazine + Oil; (3) Atrazine + Nicosulfuron + Oil; and (4) Atrazine + Mesotrione + Oil. The second factor was composed of three doses of these herbicide combinations: 100%, 75% and 50% of the recommended dose to control Alexandergrass. A control treatment, without herbicide spraying, was evaluated. Corn crop was sowed in no-till system and Alexandergrass established by self-seeding. Herbicide management in corn with Alexandergrass intercropping system is primordial to obtain good grain yields, once corn was highly affected by the forage. Herbicides and doses influenced Alexandergrass forage yield, although, all the managements allow forage availability after corn harvest. The better corn yields in the intercropping, with adequate Alexandergrass forage production, were obtained with 75% of the recommended dose of Mesotrione and Nicosulfuron associations.

No Sul do Brasil, o sistema consorciado de milho e papuã é uma alternativa interessante para aumentar a oferta de forragem aos animais e prover cobertura do solo após a colheita do milho. Objetivou-se com este estudo avaliar o efeito de herbicidas em diferentes doses sobre o rendimento de grãos de milho e de forragem de papuã (Urochloa plantaginea), num sistema consorciado. O experimento foi conduzido em blocos ao acaso, em esquema fatorial com quatro repetições. O primeiro fator foi composto por quatro associações de herbicidas: (1) Atrazina + Óleo; (2) Atrazina + Simazina + Óleo; (3) Atrazina + Nicusulfuron + Óleo; e (4) Atrazina + Mesotrione + Óleo. O segundo fator foi composto por três doses das combinações de herbicidas: 100%, 75% e 50% da dose recomendada para o controle total do papuã. Também foi avaliada uma testemunha sem a aplicação de herbicidas. A cultura do milho foi semeada em sistema de plantio direto e o papuã estabelecido por ressemeadura natural. O manejo de herbicidas é primordial para obter bons rendimento no consórcio de milho e papuã, uma vez que o milho é fortemente afetado pela pastagem em crescimento livre. As combinações e doses de herbicidas influenciaram a produção de forragem, todavia todos os manejos apresentaram forragem disponível após a colheita do milho. Os melhores rendimentos de milho, com produção satisfatória de forragem, foram obtidos com 75% da dose das associações com Mesotrione e Nicosulfuron.

Corn and alexandergrass intercropping system: influences of herbicide management on grain and forage yield / Sistema consorciado de milho e papuã: influência do manejo comherbicidas no rendimento de grãos e forragem

In Southern Brazil, intercropping system between corn and Urochloa is an interesting way to improve soil cover and animal feed after corn harvesting. This study was carried out with the objective to evaluate the effect of herbicides and its doses on corn and Alexandergrass (Urochloa plantaginea) yield, in an intercropped system. The experiment was arranged in a randomized block design, with four replications in a factorial scheme. First factor was composed of four herbicide associations: (1) Atrazine + Oil; (2) Atrazine + Simazine + Oil; (3) Atrazine + Nicosulfuron + Oil; and (4) Atrazine + Mesotrione + Oil. The second factor was composed of three doses of these herbicide combinations: 100%, 75% and 50% of the recommended dose to control Alexandergrass. A control treatment, without herbicide spraying, was evaluated. Corn crop was sowed in no-till system and Alexandergrass established by self-seeding. Herbicide management in corn with Alexandergrass intercropping system is primordial to obtain good grain yields, once corn was highly affected by the forage. Herbicides and doses influenced Alexandergrass forage yield, although, all the managements allow forage availability after corn harvest. The better corn yields in the intercropping, with adequate Alexandergrass forage production, were obtained with 75% of the recommended dose of Mesotrione and Nicosulfuron associations.(AU)

No Sul do Brasil, o sistema consorciado de milho e papuã é uma alternativa interessante para aumentar a oferta de forragem aos animais e prover cobertura do solo após a colheita do milho. Objetivou-se com este estudo avaliar o efeito de herbicidas em diferentes doses sobre o rendimento de grãos de milho e de forragem de papuã (Urochloa plantaginea), num sistema consorciado. O experimento foi conduzido em blocos ao acaso, em esquema fatorial com quatro repetições. O primeiro fator foi composto por quatro associações de herbicidas: (1) Atrazina + Óleo; (2) Atrazina + Simazina + Óleo; (3) Atrazina + Nicusulfuron + Óleo; e (4) Atrazina + Mesotrione + Óleo. O segundo fator foi composto por três doses das combinações de herbicidas: 100%, 75% e 50% da dose recomendada para o controle total do papuã. Também foi avaliada uma testemunha sem a aplicação de herbicidas. A cultura do milho foi semeada em sistema de plantio direto e o papuã estabelecido por ressemeadura natural. O manejo de herbicidas é primordial para obter bons rendimento no consórcio de milho e papuã, uma vez que o milho é fortemente afetado pela pastagem em crescimento livre. As combinações e doses de herbicidas influenciaram a produção de forragem, todavia todos os manejos apresentaram forragem disponível após a colheita do milho. Os melhores rendimentos de milho, com produção satisfatória de forragem, foram obtidos com 75% da dose das associações com Mesotrione e Nicosulfuron.(AU)