Influencia de factores endógenos (edad y sexo) en los niveles de biomarcadores de estrés oxidativo en alcatraz (Morus bassanus) / Influence of endogenous factors (age and sex) on the levels of oxidative stress biomarkers in Northern gannet (Morus bassanus)

Las aves marinas pueden ser utilizadas como bioindicadoras de las alteraciones del ambiente en que residen, identificándose en ellas distintos biomarcadores, que no informen sobre los niveles cuantitativos de contaminantes sino sobre los efectos adversos subclínicos que dichos agentes pueden causar. En el presente trabajo se han analizado los niveles de Malondialdehído (MDA) y de actividad Glutatión-S-Transferasa (GST) en muestras de hígado y riñón de 30 alcatraces (Morus bassanus) procedentes de las costas de Galicia, como posibles indicadores de estrés oxidativo en las aves. Además, se ha determinado la influencia de dos factores endógenos (sexo y edad) sobre los niveles de estos biomarcadores. En hígado los valores medios de MDA obtenidos fueron de 0,508±0,502 nmol/mg proteína, mientras que en riñón fueron de 15,67±12,18 nmol/mg proteína. La actividad GST media en hígado fue de 10,93±7,067 nmol/min/mg proteína, mucho menor que la media de los valores en riñón, que fue 62,30±26,97 nmol/min/mg proteína. En cuanto a las variaciones respecto a la edad, solo se encontraron diferencias estadísticamente significativas en riñón en la actividad GST, siendo mayor la actividad de esta enzima en alcatraces adultos que en inmaduros. Por su parte, el factor sexo no influyó en los niveles de ninguno de los biomarcadores considerados. Los resultados obtenidos apuntan a que ambos biomarcadores podrían ser de utilidad en programas de biomonitorización de contaminación ambiental centrados en el alcatraz, aunque serían necesarios estudios que consideren un mayor número de animales, incorporando un abanico más amplio de biomarcadores. (AU)

Seabirds can be used as bioindicators of changes in the environment in which they live, identifying different biomarkers in them, which do not provide information on the quantitative levels of contaminants, but on the subclinical adverse effects that these agents can cause. At the present study, the levels of Malondialdehyde (MDA) and glutathione-S-transferase (GST) activity in liver and kidney samples of 30 gannets (Morus bassanus) from the coast of Galicia have been determined, as suitable biomarkers of oxidative stress on birds. In addition, the influence of two endogenous factors (sex and age) on the levels of these biomarkers has been determined. In the liver, the mean values of MDA were 0.508 ± 0.502 nmol/mg protein, while in kidney they were 15.67 ± 12.18 nmol/mg protein. On the other hand, mean GST activity in the liver was 10.93 ± 7.067 nmol/min/mg protein, much lower than the mean activity values found in kidney, which were 62.30 ± 26.97 nmol/min/mg protein. Regarding the variations with respect to age, statistically significant differences were only found in the kidney in GST activity, the activity of this enzyme being higher in adult gannets than in immature ones. Secondly, the gender factor did not influence the levels of any of the biomarkers considered. The obtained results indicate that both biomarkers could be useful in biomonitoring programs of environmental contamination focused on the gannet, although studies that consider a larger number of animals, incorporating a broader range of biomarkers, would be necessary. (AU)

Ensayo estandarizado (ISO 17512) de comportamiento de evitación de suelos contaminados. Efecto del pesticida dimetoato sobre la lombriz de tierra Aporrectodea caliginosa / Standardized avoidance test (ISO 17512) for contaminated soils. Effect of the pesticide dimethoate on the earthworm Aporrectodea caliginosa

La creciente preocupación por el bienestar animal ha propiciado el rechazo por parte de la sociedad a la utilización de animales en experimentación. Por este motivo, actualmente se están desarrollando métodos alternativos que cumplan con el principio de las 3Rs (reemplazar, reutilizar y refinar). Muchos de estos métodos se basan en la utilización de organismos inferiores, como las lombrices de tierra. El presente estudio desarrolla el ensayo estandarizado de la Organización Internacional de Normalización (ISO) 17512-1:2008, en el que se evalúa la toxicidad producida por el plaguicida organofosforado dimetoato en el suelo, utilizando la capacidad de repulsión o evitación que presentan las lombrices de tierra pertenecientes a la especie Aporrectodea caliginosa. Las concentraciones seleccionadas han sido 0,06, 0,3 y 1,5 mg/kg de suelo, ensayada cada una de ellas por triplicado, empleando 10 lombrices por cada réplica. Los resultados reflejan la capacidad de las lombrices de tierra de la especie Aporrectodea caliginosa para evitar suelos contaminados con el formulado comercial de dimetoato. Por otra parte, se confirma la tendencia de las lombrices a evitar el suelo contaminado a medida que aumenta la concentración de plaguicida ensayada, con significación estadística a la dosis más alta empleada (1,5 mg/kg). (AU)

The increasing concern about animal wellness has induced the repulse of society to the use of animals in research. For this reason, alternative methods which comply with the 3Rs principle (Replace, Reuse and Refine) are currently being developed. Many of these methods are based on the use of lower organisms on the evolutionary scale, such as earthworms. The present study develops the standardized test of the International Organization of Standardization (ISO) 17512-1:2008, in which the toxicity produced by the pesticide organophosphate dimethoate in the soil is evaluated, using the capacity of repulsion or avoidance that presents the earthworms Aporrectodea caliginosa. The assayed concentrations were 0.06, 0.3 and 1.5 mg/kg of soil, each one tested in triplicated, using 10 earthworms for each repetition. The results reflect the ability of earthworms of the species Aporrectodea calliginosa to avoid soils contaminated with the commercial formulation of dimethoate. On the other hand, the tendency of worms to avoid contaminated soils is confirmed as the concentration of pesticide increases, with statistical significance at the highest concentration used (1.5 mg/kg). (AU)

Ensayo estandarizado (ISO 17512) de comportamiento de evitación de suelos contaminados II. Respuesta de distintos biomarcadores tras la exposición a dimetoato en la lombriz de tierra Aporrectodea caliginosa / Standardized avoidance test (ISO 17512) for contaminated soils II. Response of different biomarkers after exposure to dimethoate in earthworm Aporrectodea caliginosa

En la primera parte del presente estudio, publicado en 2021, se mostraron los resultados obtenidos al aplicar el ensayo estandarizado de la Organización Internacional de Normalización (ISO) 17512-1:2008. En dicho trabajo se evaluó la toxicidad producida por el plaguicida organofosforado dimetoato en el suelo, utilizando la capacidad de repulsión o evitación que presentan las lombrices de tierra de la especie Aporrectodea caliginosa. En esta segunda parte, para evaluar los efectos subletales producidos por el dimetoato sobre las lombrices, se han determinado como biomarcadores la actividad de la enzima acetilcolinesterasa (AChE, cuya inhibición es el principal mecanismo de acción de este tipo de compuestos) y la actividad glutatión S-transferasa (GST, que comúnmente se activa como mecanismo de detoxificación de plaguicidas). Las concentraciones seleccionadas han sido 0,06, 0,3 y 1,5 mg/kg de suelo, ensayada cada una de ellas por triplicado, empleando 10 lombrices por cada réplica.La actividad AChE se inhibió significativamente en la exposición a las tres concentraciones empleadas. No se ha producido aumento de la actividad GST que, por el contrario, aparece significativamente inhibida a la concentración más alta de plaguicida ensayada. La falta de una inducción de la actividad GST puede deberse a que el mecanismo de detoxificación no se ha puesto en marcha por el corto tiempo de exposición al plaguicida. Estos resultados reflejan la sensibilidad de la AChE como biomarcador de la contaminación de los suelos con organofosforados. (AU)

In the first part of this study, published in 2021, the results obtained when applying the standardized test of the International Organization of Standardization (ISO) 17512-1:2008 were shown. In this study, the toxicity produced by the pesticide organophosphate dimethoate in the soil was evaluated, using the capacity of repulsion or avoidance that presents the earthworms Aporrectodea caliginosa. To evaluate the sublethal effects produced by dimethoate on worms, the activities of the acetylcholinesterase enzyme (AChE, the inhibition of which is the main mechanism of action of this type of compound) and glutathione S-transferase enzyme (GST, which is commonly activated as a pesticide detoxification mechanism) have been determined. The commercial product called DIMAFID40, whose active substance is the organophosphate pesticide dimethoate, was used. The selected concentrations were 0.06, 0.3 and 1.5 mg / kg of soil, each one tested in triplicate, using 10 worms per replicate.The AChE activity was significantly inhibited after exposure to the three assayed concentrations. With respect to GST activity, it was not increased but significantly inhibited after exposition to the highest concentration of pesticide. The non-appearance of an induction of GST activity may be due to the fact that the detoxification mechanism has not been started because the time of exposure to the pesticide has been too short. These results reflect the sensibility of AChE as a biomarker of the contamination in soils with organophosphate. (AU)

Concentrations of chlorinated pollutants in adipose tissue of yellow-legged gulls (Larus michahellis) from Spain: Role of gender and age.

Concentrations of 7 different polychlorinated biphenyl (PCB) congeners, and eleven organochlorine pesticides (OCPs) and metabolites, including DDTs (dichlorodiphenyltrichloroethane), HCHs (hexachlorocyclohexane isomers), Endosulfan, Endosulfan sulfate, Endrin, Dieldrin and HCB (hexachlorobenzene), were determined in adipose tissue of 57 yellow-legged gulls collected from NW and N Spain. Furthermore, the possible differences due to two endogenous factors, age and gender, were determined. All the analyzed PCBs were detected in over 66% of the samples, with levels of 291.9 (PCB 180), 34.5 (PCB 118), 0.7 (PCB 28), 432.6 (PCB 153), 225.5 (PCB 138), 1.3 (PCB 101) and 0.4 (PCB 52) µg/kg of adipose tissue. With respect to the OCPs and metabolites, only 4,4'-DDE and HCB were detected in more than 50% of the samples, with means of 360.6 and 2.5 µg/kg of adipose tissue, respectively. From all the considered contaminants, only 4,4'-DDE levels presented significant differences depending on the gender, with females showing higher values than males (p < 0.01). Significant differences (p < 0.001) were also found related to age for the levels of PCBs 180, 138, 101, 28 and 153, as well as 4,4'-DDE, with adult levels being higher than those in young birds. The results of the present study constitute a baseline to better assess the environmental impacts of PCB and OCP contamination at other coastal sites for future biomonitoring studies, with particular emphasis on gender- and age-related differences.

Concentrations of Metals, Metalloids, and Chlorinated Pollutants in Blood and Plasma of White Stork (Ciconia ciconia) Nestlings From Spain.

The aim of this study was to determine the levels of different inorganic elements (lead [Pb], mercury [Hg], and arsenic [As]) and persistent chlorinated pollutants (including polychlorinated biphenyls [PCBs] and organochlorine pesticides [OCPs]) in blood and plasma of White stork (Ciconia ciconia) nestlings from northwest (NW) Spain. The concentrations of PCBs were lower than the limit of detection in all samples. The OCPs γ-HCH, 4,4'-DDE, HCB, and endosulfan were detected most frequently in plasma from White stork nestlings. These OCPs were detected in 98, 54, 39, and 37 % of all samples, respectively. However, the concentrations of organic pollutants were lower than the risk thresholds for birds. The mean levels of the inorganic elements Pb, Hg, and As were found to be 36.92 ± 33.48, 16.48 ± 12.87, and 9.813 ± 13.84 µg/L, respectively. These levels were also lower than the risk thresholds for birds. This study not only provides a snapshot of the levels of both inorganic and organic contaminants in wild White storks in NW Spain, it also provides a useful baseline for biomonitoring levels of the measured contaminants in this area.

Effects of deltamethrin on biometric parameters and liver biomarkers in common carp (Cyprinus carpio L.).

The present study is aimed to evaluate the effect of sublethal exposure to the pyrethroid pesticide deltamethrin, according to biometric parameters and important liver biomarkers in the common carp (Cyprinus carpio). Fish were exposed for 4, 15 and 30 days to deltamethrin mixed to the aquaria water at the concentrations of 0.08, 0.4 and 0.8µg/L. The exposure did not affect fish biometric parameters. Glutathione-S-transferase (GST) activity in liver (hepatopancreas) increased in fish exposed to the high concentration of pesticide only after 30 days when compared to controls. A significant increase of malondialdehyde (MDA) content (79.4% and 90.2% of control) was remarked after 15 and 30 days of exposure to the highest concentration of pesticide. Catalase activities (CAT) went up after 4 days of was to the concentration of 0.4µg/L and 0.8µg/L and at 15 days of exposure to 0.4µg/L. The most significant change of glutathione reductase (GR) activity was recorded at the fourth day, when GR activity was significantly increased after exposure to the concentrations of 0.4µg/L and 0.8µg/L of deltamethrin.

Evaluation of reagent strips for the rapid diagnosis of nitrite poisoning.

Two commercial urine test strips based on the Griess nitrite-specific diazonium salt reaction, having sulfanilamide and para-arsanilic acid as substrates, respectively, were studied as qualitative tests in the rapid diagnosis of nitrite/nitrate poisoning. Their usefulness was compared to other rapid tests, such as the sulfanilic acid-1 naphthylamin and diphenylamine blue tests. The practical sensitivity limit to nitrites in plasma and in water of both the reagent strips and SA-1NA test was 0.50 micrograms NO2/mL, while the diphenylamine test, which is not nitrite specific, showed a positive reaction to nitrites in plasma and in water above 50 micrograms NO2/mL and 5 micrograms NO2/mL, respectively. The in vitro assays were evaluated in vivo by the sublethal intoxication of a sheep with nitrite, demonstrating that commercial urine test strips may be useful for the rapid diagnosis of nitrite/nitrate poisoning.

An outbreak of lupinosis in sheep.

Lupinosis is a mycotoxicosis caused by the ingestion of toxins produced by the fungus phomopsis leptostromiformis which grows on lupin plants. An outbreak of natural lupinosis in lambs occurred in Caceres, Spain. Clinical signs were inappetence, depression, constipation, weakness and different degrees of jaundice. Blood samples were analysed every 7 d for 5 w for hematocrit, total protein, glucose, total bilirubin, and GOT, GPT and alkaline phosphatase activities. The last 4 parameters were increased and returned to normal values after 2-3 w. The liver was swollen and a bright yellow color; microscopically fatty metamorphosis, necrotic areas and infiltration of polymorphonuclears were observed. This is the first time that lupinosis is described in Spain.