Water and sediment toxicity and hazard assessment of DCOIT towards neotropical marine organisms.

DCOIT is an effective antifouling biocide, which presence in the environment and toxicity towards non-target species has been generating great concern. This study evaluated the waterborne toxicity of DCOIT on marine invertebrates (i.e., survival of brine shrimp Artemia sp., larval development of the sea urchin Echinometra lucunter and the mussel Perna perna), as well as DCOIT-spiked-sediment toxicity on the fecundity rate of the copepod Nitrocra sp. And the mortality of the amphipod Tiburonella viscana. The data outcomes were used to calculate environmental hazards and risks, which were compared to their corresponding values obtained from temperate regions. Waterborne toxicity can be summarized as follows: Artemia sp. (LC50-48h = 163 (135-169) µg/L), E. lucunter (EC50-36h = 33.9 (17-65) µg/L), and P. perna (EC50-48h = 8.3 (7-9) µg/L). For whole-sediment toxicity, metrics were calculated for T. viscana (LC50-10d = 0.5 (0.1-2.6) µg/g) and Nitrocra sp, (EC50-10d = 200 (10-480) µg/kg). The DCOIT hazard was assessed for both tropical and non-tropical pelagic organisms. The predicted no-effect concentration (PNEC) for tropical species (0.19 µg/L) was 1.7-fold lower than that for non-tropical organisms (0.34 µg/L). In whole-sediment exposures, DCOIT presented a PNEC of 0.97 µg/kg, and the risk quotients (RQs) were >1 for areas with constant input of DCOIT such as ports ship/boatyards, marinas, and maritime traffic zones of Korea, Japan, Spain, Malaysia, Indonesia, Vietnam, and Brazil. The presented data are important for supporting the establishment of policies and regulations for booster biocides worldwide.

Using a tiered approach based on ecotoxicological techniques to assess the ecological risks of contamination in a subtropical estuarine protected area.

This study sought to assess the ecological risks of sediments from the northern portion of an estuarine protected area (Cananéia-Iguape-Peruíbe Protected Area--CIP-PA). The CIP-PA is located on the southern coast of São Paulo State, Brazil and is influenced by former mining activities along the Ribeira de Iguape River (RIR). We used a tiered approach based on multiple lines of evidence (geochemical analyses, toxicity tests, and whole sediment toxicity identification and evaluation) in order to assess environmental quality. The sediments presented a heterogeneous composition, but the samples collected close to the RIR exhibited higher concentrations of metals (Cd, Cr, Cu, Pb) and toxicity. Multivariate analysis showed that toxicity was associated with metals, mud, organic matter, and CaCO3 quantities. The whole-sediment toxicity identification evaluation approach indicated that ammonia and metals were responsible for sediment toxicity. Overall, we concluded that the sediments collected at depositional areas from the northern portion of the CIP-PA presented high levels of metals, which originated from former mining areas located in the upper RIR basin, and that this contamination had toxic effects on aquatic invertebrates. The tiered approach was useful for identifying the degradation of sediment quality and also for indicating the causes of toxicity. Because the CIP-PA is an important estuarine protected area that is ecologically at risk, large-scale measures are required to control the sources of contamination.

Incidência de doenças no pós-parto de primíparas da raça holandesa alimentadas com diferentes fontes energéticas durante o período de transição / Disease incidence in the postpartum period of primiparous Holstein cows fed diets with different energetic sources during the transition period

Avaliaram-se o efeito da adição de diferentes fontes energéticas na dieta de vacas primíparas leiteiras, durante o período de transição, sobre a produção e a composição do leite, as ocorrências clínicas no pós-parto e sua relação com as concentrações plasmáticas de ácidos graxos não esterificados (AGNE). Foram utilizadas 50 vacas primíparas da raça Holandesa no período de 28 dias antes da data prevista do parto até o 21º dia pós-parto. Os animais foram designados aos grupos: controle, Megalac- E®, soja tostada (ST) ou propileno glicol (PG). Avaliações clínicas foram realizadas todos os dias. Amostras de sangue foram coletadas no pré e pós parto, antes da primeira alimentação do dia, para avaliação de AGNE. Os grupos Megalac- E® e propileno glicol apresentaram maior volume de leite corrigido para 3,5 por cento de gordura (LCG 3,5 por cento) em relação ao grupo soja tostada (P=0,05). Nos grupos controle, Megalac- E® e soja tostada, os valores de AGNE aumentaram até o parto, seguidos de queda após o parto. Essa queda foi menos acentuada no grupo-controle, que apresentou equação de regressão quadrática, estando associado à maior incidência de afecções no pós-parto. O grupo Megalac-E® apresentou comportamento cúbico, o soja tostada hiperbólico, e o propileno glicol quadrático.

The purpose of this trial was to evaluate the effect of different energy sources added to the diet over milk production and composition, disease incidence during postpartum period and its relationship to NEFA concentrations during the transition period. Fifty primiparous Holstein dairy cows were used from 28 days before the expected calving date until 21 days postpartum. Cows were randomly distributed in four groups, being: control, Megalac- E®, toasted soybean (TS) and propylene glycol (PG). Clinical evaluations were performed during all experimental days. Blood samples were collected in pre and postpartum periods, before the first feeding of sampling day in order to determine NEFA prolife. Megalac- E® and propylene glicol groups showed greater milk production corrected to 3.5 percent fat compared to group toasted soybean (P=0.05). In control groups, Megalac-E® and toasted soybean values of NEFA increased until delivery and then decreased. This decrease was less pronounced in the control group that showed a quadratic regression equation associated with higher incidence of postpartum disorders. The Megalac-E® group showed a cubic model, the toasted soybean hyperbolic and propylene glycol quadratic equations.

Viabilidade financeira da utilização de quatro ordenhas nos primeiros 21 dias da lactação em vacas mestiças F1 Holandês/Zebu / Financial viability analyses of four milkings in the first 21 days of lactation in F1 crossbred Holstein-Zebu cows

Avaliou-se financeiramente o efeito de quatro ordenhas diárias nos primeiros 21 dias da lactação, seguidas de duas ordenhas diárias, com ou sem a sucção de leite pelo bezerro em um dos tetos durante a ordenha. Foram utilizadas 53 vacas F1 Holandês/Zebu multíparas. A produção e a composição do leite foram mensuradas a cada quatro dias até o 33º dia da lactação e, posteriormente, a cada 15 dias. Como indicador do desempenho financeiro dos diferentes grupos, foi utilizada a margem bruta. O experimento foi desenvolvido em delineamento inteiramente ao acaso, em arranjo fatorial 2x2. As produções médias de leite foram 16,7, 17,2, 19,0 e 18,9kg/d (PÂ0,01) para vacas ordenhadas duas e quatro vezes por dia, com ou sem a sucção do leite pelo bezerro durante a ordenha, respectivamente. O aumento da frequência de ordenhas nos primeiros 21 dias da lactação proporcionou incremento na produção de dois litros/dia e 17,3 por cento na margem bruta estimada com a venda de leite.

Fifty-three F1 crossbred Holstein-Zebu cows were used to evaluate financially the effects of four daily milkings until lactation day 21, and after this day two milkings, with or without suckling by the calf in one teat during milking. Milk production and composition were measured each four days until lactation day 33, and then each 15 days until the end of lactation. The experiment followed a completely randomized design in a 2x2 factorial. To analyze the financial viability of the different groups, the gross margin was used, as financial indicator. Milk productions were 16.7, 17.2, 19.0, and 18.9kg/day (PÂ0.01) for cows milked twice or four times a day with or without suckling by the calf, respectively. The rise of milking frequency increased milk production in two liters per day, and in 17.3 percent of estimated gross margin from the sale of milk.

Primeira onda folicular e ovulação de vacas primíparas da raça Holandesa alimentadas com diferentes fontes energéticas durante o período de transição / First follicular wave and first postpartum ovulation of primiparous Holstein dairy cows receiving diets with different energetic sources during the transition period

Avaliou-se o efeito da adição de diferentes fontes energéticas na dieta de vacas leiteiras, durante o período de transição, sobre a primeira onda folicular e o intervalo parto-primeira ovulação. Foram utilizadas 40 vacas primíparas da raça Holandesa, no período de 28 dias antes da data prevista do parto até o 46º dia pós-parto. As vacas foram submetidas a quatro tratamentos (grupos) durante o período de transição: grupo-controle e grupos tratados com, Megalac-E (sais de cálcio de ácidos graxos da soja), soja tostada ou propileno-glicol. Avaliações ultrassonográficas foram realizadas do 10º ao 46º dia pós-parto, com a classificação dos folículos ovarianos em quatro classes (I, II, III e IV) de tamanho e do registro do volume do tecido luteal. Amostras de sangue foram coletadas nos dias 10, 17, 24, 31, 38 e 45 após o parto para análise de progesterona. O padrão de crescimento folicular mais eficiente foi apresentado pelos animais dos grupos Megalac-E e propileno-glicol, que foram caracterizados pela redução no número de folículos de classes I e II e aumento no número de folículos de classes III e IV. Os intervalos entre o parto e a primeira ovulação dos grupos controle, Megalac-E, soja tostada e propileno-glicol foram de 29, 23, 30 e 37 dias, respectivamente (P<0,05).

The effects of different energy sources added to the diet on the first postpartum ovarian follicle wave and first postpartum ovulation were evaluated. Forty primiparous Holstein dairy cows were used from 28 days before the expected calving date until 46 days postpartum. Cows were randomly allotted to the following groups: control, Megalac-E calcium salts of soybean fatty acid), toasted soybean and propylene glycol. Ovarian structures were scanned using ultrasound from 10 to 46 days postpartum. Follicles were classified according to the diameter in classes I, II, III, and IV and the luteal tissue volume was registered when present. Blood samples for progesterone dosage were colleted on days 10, 17, 24, 31, 38, and 45 post-partum. Follicular growth from groups of salts of polyunsaturated fatty acids and propylene glycol showed to be the most efficient and were characterized by a reduction in the number of classes I and II follicles and an increase in classes III and IV follicles. The first postpartum ovulation after calving for control, salts of polyunsaturated fatty acids, toasted soybean and propylene glycol animal groups occurred at 29, 23, 30, and 37 days, respectively (P<0.05).

The potentiation of the histamine release induced by adenosine in mast cells from guinea pig lung and heart: sharp dependence on the time of preincubation.

We studied here the effect of a wide range of adenosine concentration and time of preincubation, on the histamine release induced in the guinea pig mast cells by different stimulus. Adenosine (10(-5)-10(-3)m) potentiated the histamine release induced by antigen in the guinea pig heart (isolated and dispersed tissue) and lung mast cells but not induced by ionophore A23197. The potentiation caused by adenosine (10(-4)m) was maximum after 1-3 min of preincubation and is probably an extracellular effect since it was not avoided by dipyridamol (3x10(-7)-10(-6)m) that inhibit the uptake of adenosine. Similar potentiation was also produced by the adenosine mimetic 2-chloroadenosine (10(-5)m) and both effects were inhibited by 8-phenyltheophylline indicating an effect on the type A receptors. It is suggested that the adenosine potentiation may not be related to changes on the cyclic AMP levels. 2000 Academic Press@p$hr