This study evaluated the efficacy of albendazole, ivermectin, levamisole, mebendazole and praziquantel on monogeneans of Colossoma macropomum, based on in vitro and in vivo assays. In vitro assays indicated that albendazole (500, 100, 1,500 and 2,000 mg/L), ivermectin (200, 250, 300 and 350 mg/L) and levamisole (50, 75, 100 and 125 mg/L) were 100% effective against Anacanthorus spatulatus, Notozothecium janauachensis, Mymarothecium boegeri and Linguadactyloides brinkmanni, while mebendazole (125, 150, 175 and 200 mg/L) and praziquantel (5, 10, 15 and 20 mg/L) were ineffective. Fish mortality in 24 hr therapeutic baths with 500 mg/L of albendazole was 6.6%, but the behaviour of the animals remained unchanged, while 200 mg/L of ivermectin caused lethargy, signs of hypoxia and 100% mortality within 2 hr, and 125 mg/L of levamisole caused no mortality. The efficacy of 500 mg/L of albendazole was 48.6% in the 24 hr baths, while that of 125 mg/L levamisole was 88.2%. Although ivermectin showed in vitro efficacy, the lowest concentration used in baths was highly toxic to fish. Therefore, we recommend the use of 125 mg/L of levamisole to control and treat monogenean infestations on C. macropomum in fish farming.

Avaliou-se a trajetória genética do crescimento de codornas de corte (pesos corporais nos dias 1, 7, 14, 21, 28, 35 e 42 de idade) de dois grupos genéticos, por modelos de regressão aleatória, sob modelo animal, obtendo-se estimativas de parâmetros genéticos visando definir a idade que resultaria em maior resposta à seleção. Foram pesadas 2.432 e 2.478 codornas, respectivamente, dos grupos genéticos EV1 e EV2, obtidas em três gerações de seleção. Os parâmetros genéticos foram estimados utilizando-se a sub-rotina Dxmrr do DFReml. As estimativas de herdabilidade dos pesos corporais variaram, respectivamente, de 0,01 a 0,50, para o grupo genético EV1, e de 0,01 a 0,10, para o EV2, sendo as maiores estimativas obtidas para peso corporal no 42º dia de idade, em ambos os grupos genéticos. As correlações genéticas entre o peso a um dia e os demais pesos corporais, em ambos os grupos, foram negativas, e as correlações de ambiente permanente, de modo geral, foram maiores para EV2. Pode-se concluir que, para ambos os grupos, a seleção é mais eficiente se realizada no 42º dia de idade, porém respostas poderiam ser obtidas se as codornas fossem selecionadas em idades mais jovens para o grupo EV1.

This study examined the in vitro and in vivo, histopathological, anti-parasitic and hematopathological effects of the essential oil of Lippia origanoides on Colossoma macropomum. Essential oil concentrations of 10, 20, 40, 80, 160 and 320 mg•L −1 were tested in vitro against monogenoideans (Anacanthorus spathulatus, Notozothecium janauachensis and Mymarothecium boegeri) from the gills of C. macropomum. Concentrations of 320 and 160 mg•L −1 were 100% effective against these parasites within 20 and 60 min of exposure, respectively. The 80 mg•L −1 concentration was approximately 80% effective with 3 h of exposure, reaching 100% with 6 h of exposure. The 40 mg•L −1 concentration was also 100% effective with 6 h of exposure. The other concentrations were only weakly effective in vitro. Parasite mortality in controls (water or water + alcohol) began after 3 h, with 100% mortality after 8 h. In vivo tests, in which fry of C. macropomum were placed in baths with 20 mg•L −1 of the essential oil for 60 min, and 40 mg•L −1 for 30 min, did not lead to reductions in parasite abundances. In addition, the essential oil had an anaesthetic effect on fish, increased total protein levels, increased monocyte and neutrophil numbers, and reduced haematocrit. Slight to moderate and severe damage was observed in the gills of C. macropomum fingerling immediately after exposure to the essential oil, and 24 h after the treatments were applied, with no difference between treatments. Histological changes observed in the gills after exposure to concentrations of 20 and 40 mg•L −1 of L. origanoides essential oil were: hyperplasia and fusion of the lamellar epithelium, capillary dilation, displacement of the lamellar epithelium, and lamellar aneurism and epithelial rupturing with haemorrhaging. Oedema, mucous and chloride cell proliferation, lamellar hypertrophy, congestion and necrosis were less frequently observed. It can be concluded that the essential oil of L. origanoides was dose-dependent in vitro effect against monogenoidean parasites of C. macropomum. Unfortunately, the low concentrations tolerated by the fish in the vivo assay (20 and 40 mg•L −1) was not effective. Statement of relevance: The manuscript represents original research on use of the essential oil of Lippia origanoides against ectoparasites of Colossoma macropomum, an important finfish of Amazon region. This manuscript includes treatment in vitro against monogenoideans, and in vivo against protozoans and monogenoideans. Besides, histopathological and hematological analysis of the fish exposed to different concentrations of L. origanoides, a medical plant from North, Central and South America, were performed.

Uso de redes neurais artificais na predição de valores genéticos para peso aos 205 dias em bovinos da raça Tabapuã

RESUMOEstudou-se a exigência de proteína bruta e energia metabolizável para codornas européias EV1, durante três períodos experimentais, 7-21, 22-42 e 7-42 dias de idade, utilizando-se 576 aves, de ambos os sexos. O delineamento experimental foi inteiramente ao acaso, em arranjo fatorial 4 x 2, quatro níveis de proteína bruta (22, 24, 26 (CP) and 2900kcal of ME/kg of diet in the initial period (7-21 days of age) and 22% of CP and 2900kcal of ME/kg of diet in the whole period (7-42 days of age).