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Towards understanding the effects of oceanic plastic pollution on population growth for a South American fur seal (Arctocephalus australis australis) colony in Chile
2021
Perez-Venegas, Diego Joaquín | Valenzuela-Sánchez, Andrés | Montalva, Felipe | Pavés, Héctor | Seguel, Mauricio | Wilcox, Chris | Galbán-Malagón, Cristóbal
Entanglement of pinnipeds with plastic debris is an emerging conservation and animal welfare issue worldwide. However, the origins and long-term population level consequences of these entanglements are usually unknown. Plastic entanglement could produce a combination of wounds, asphyxiation, or inability to feed that results in the death of a certain percentage of individuals from the total population. In this research, we report on the consequent effect of plastic entanglement on population growth demographics in a South American fur seal (Arctocephalus australis australis) colony on Guafo Island, southern Chile. Using a stochastic matrix population model structured according to age and sex, and assuming an otherwise stable population, we explored population growth rates under five scenarios with differing rates of entanglement: A) a zero rate of plastic entanglement, B) entanglement rates (number of entangled individuals as a proportion of the total number of individuals) as observed in our study population (overall entanglement ratio of 1.2 × 10⁻³); and for the other scenarios, entanglement ratios as reported in the literature for other pinniped colonies around the world: C) 3.04 × 10⁻³, D) 4.42 × 10⁻², and E) 8.39 × 10⁻². Over the 30 years forecasting period and starting with a population size of ∼2950 individuals, the population growth rate was lower under all scenarios with rates of entanglement greater than zero (scenarios B-E). In comparison with scenario A, at the end of the 30-year period forecasted, we calculated a projected decrease in population size of between 20.34% (scenario B) and 91.38% (scenario E). These results suggest that even the lowest levels of entanglement in pinnipeds as reported in the literature might have significant effects over time on population-level dynamics. Our research offers potential insight when devising policy for the management and limitation of plastic pollution in the oceans, and indeed for the conservation and management policy of affected marine species. Furthermore, whilst there are some limitations to our methodology, it offers a straightforward and potentially useful approach for the standardized prediction of impacts at a population level of different rates of plastic pollution and entanglement and could be applied in distinct populations of the same species around the world.
اظهر المزيد [+] اقل [-]Entanglement of Cape fur seals (Arctocephalus pusillus pusillus) at colonies in central Namibia
2021
Curtis, S. | Elwen, S.H. | Dreyer, N. | Gridley, T.
Marine pollution is increasing, and pinnipeds are commonly affected by entanglement in waste. We investigated entanglement rates, common materials, and the demographic profile of Cape fur seals (Arctocephalus pusillus pusillus) affected at two Namibian colonies. Overall, we identified 366 cases of entanglement, and present a global rate of entanglement of 0.17%. Entanglement rates were 0.17% and 0.15% for the Pelican Point and Cape Cross colonies, respectively. We identified 17% more entanglements through photographs than binocular scans. Of the 347 entanglements analysed in detail, juveniles were most commonly affected and fishing materials were the primary cause of entanglements (53%), with 8% of entangled seals exhibiting ‘very severe’ injuries. Overall, 191 individuals were successfully disentangled, and citizen scientists contributed 51% of total entanglement data. We highlight the negative impact of plastic marine waste among seals and the importance of disentanglement for individual animal welfare.
اظهر المزيد [+] اقل [-]Quantification of gear inflicted damages on trawl-caught haddock in the Northeast Atlantic fishery
2020
Sistiaga, Manu | Herrmann, Bent | Brinkhof, Jesse | Larsen, Roger B. | Jacques, Nadine | Santos, Juan | Gjøsund, Svein Helge
External damages are indicators of the overall quality of fish and fish welfare. Haddock is an important commercial species widespread in the North Atlantic, but few studies related to quality have been carried out on this species. We studied the levels of external damages on haddock captured with a demersal trawl in the Northeast Atlantic. Further, we investigated to what extent the compulsory sorting grid and diamond mesh codend gear configuration employed in this trawl fishery is responsible for the external damages observed during the capture process. We evaluated external damages on 563 haddock captured over 22 hauls. In general, the results showed that catching haddock without any gear inflicted damages using demersal trawls is challenging. However, the results also showed that the severity of most damages is low and the probability to catch haddock with no external damage can be significantly increased removing the grid and changing codend design.
اظهر المزيد [+] اقل [-]Survival and movements of Magellanic penguins rehabilitated from oil fouling along the coast of South America, 2000–2010
2012
Ruoppolo, Valeria | Vanstreels, Ralph Eric Thijl | Woehler, E. J. (Eric J.) | Heredia, Sergio Andres Rodríguez | Adornes, Andréa Corrado | Silva-Filho, Rodolfo Pinho da | Matus, Ricardo | Poleschi, Carla | Griot, Karen | Kolesnikovas, Cristiane K Miyaji | Serafini, Patrícia
Oil pollution is a significant conservation concern. We examined data from six institutions along the coast of South America: Emergency Relief Team of the International Fund for Animal Welfare, Fundación Mundo Marino, Centro de Recuperação de Animais Marinhos, Natura Patagonia, Associação R3 Animal, and Mar del Plata Aquarium and data from resightings in Argentina, Brazil, Chile and Falkland/Malvinas Islands. From 2000 to 2010, 2183 oiled Magellanic penguins were rehabilitated as part of the routine activities of these institutions or during emergency responses to eight oil spills in which they were involved; all rehabilitated penguins were flipper banded and released. Since their release, 41 penguins were resighted until 31 December 2011. The results demonstrate that, when combined with other prevention strategies, the rehabilitation of Magellanic penguins is a strategy that contributes to the mitigation of adverse effects of oil spills and chronic pollution to the species.
اظهر المزيد [+] اقل [-]Trace and rare earth element bioaccumulation in the spotted dogfish (Scyliorhinus stellaris)
2022
Squadrone, Stefania | Biancani, Barbara | Da Rugna, Cristiano | Favaro, Livio | Pederiva, Sabina | Abete, Maria Cesarina
Metals (trace elements and rare earth elements, REEs) were analysed by inductively coupled plasma-mass spectrometry in blood, the liver, the kidney and muscle of ex situ spotted dogfish (Scyliorhinus stellaris). The controlled environment in which these elasmobranchs were hosted allowed to assess a baseline level of metals in the different organs since exposure via water and food can be easily monitored. The highest arsenic, chromium, copper, and iron values were found in the liver, cobalt in the kidney, and cadmium and rubidium in muscle. The highest total trace elements content was found in the trend liver (75 mg kg⁻¹) > blood (33 mg kg⁻¹) > muscle (31 mg kg⁻¹) > kidney (10 mg kg⁻¹), while the ΣREEs was the liver (30 μg kg⁻¹) > muscle (15 μg kg⁻¹) > kidney (13 μg kg⁻¹) > blood (4.1 μg kg⁻¹). Between REEs, the most represented element was scandium. Significant differences in the concentration of metals among organs were observed for almost all elements. Nonessential elements were generally lower and essential elements higher in the examined specimens compared to wild elasmobranchs, suggesting a close relationship between a balanced diet and animal welfare.
اظهر المزيد [+] اقل [-]Impact of bacterial aerosol, particulate matter, and microclimatic parameters on animal welfare in Chorzów (Poland) zoological garden
2021
Grzyb, Jacek | Pawlak, Krzysztof
Zoos are very popular facilities visited by entire families with children, who come there to watch live animals. Zoos also provide workplaces for a large number of people directly looking after the animals. For places designed to house animals, regardless of whether they are farm animals, pets, or zoo animals, a higher concentration of both dust and potentially harmful bioaerosols can be expected. Unfortunately, there are almost no studies concerning the concentration of bacterial bioaerosols and particulate matter in animal shelters that would answer the question whether the level of these pollutants is constant or variable and dependent on a particular zoo, group of animals, their number in enclosures, or season. This study aimed to assess the levels of bacterial aerosol in rooms intended for animals (giraffes, camels, elephants, kangaroos, and colobinae) in the Silesian Zoological Garden in Chorzów (Poland). The bioaerosol samples were collected using a six-stage Andersen cascade impactor to assess the concentrations and size distribution of airborne bacteria. Particulate matter (PM10) was assessed using an electronic dust meter. Measurements of microclimate parameters were carried out using the Airflow™ Instruments Velocity Meter TA440, while gas concentrations were determined applying GFG Microtector II G450. The results showed that the concentration of airborne bacteria varied significantly between facilities for the analyzed animal groups. The lowest concentration of the total bacterial aerosol was observed in enclosures for colobinae (approx. 850 CFU/m³), while the highest—in rooms for elephants (approx. 105,600 CFU/m³). The average share of respirable fraction of bacteria was quite high, with values ranging from 62.9 (colobinae) to 86.9% (elephants), indicating potential harmfulness to the health of exposed people. PM10 concentrations were relatively low (10–86 μg/m³) and did not exceed the limit values for occupational exposure. Moreover, the levels of bacterial bioaerosol in almost all cases did not exceed the limit values. As the animals constitute a significant source of bioaerosol, attention should be paid to thorough cleaning of animals and their shelters, as well as maintaining appropriate levels of microclimate parameters in the facilities.
اظهر المزيد [+] اقل [-]Pig barns ammonia and greenhouse gas emission mitigation by slurry aeration and acid scrubber
2020
Mostafa, Ehab | Selders, Anne | Gates, Richard S. | Buescher, Wolfgang
Livestock production is associated with several gaseous pollutant emissions to the environment. These emissions can degrade local and regional air quality, contribute to surface water eutrophication and acid rain, and contribute to the greenhouse gas footprint of the production sector. Modern production systems must balance animal welfare and environmental pollution potential with economic reality, which is a great challenge to maintain as global demand for animal protein increases. Accordingly, gaseous emission technologies were the main target for this research, in which mitigating gas emissions of ammonia, nitrous oxide, and methane from pig production facilities via slurry aeration system was tested. Five treatments with different airflow rates in the test room were examined continuously over a period of 6 weeks and the results were compared with the control room. Test results indicate that the highest mitigation potentials were 12, 57.6, and 10.4% for nitrous oxide, methane, and ammonia, respectively. Subsequently directing exhaust air into a sulfuric acid air scrubber at 3.0 pH further reduced total ammonia emissions by 80 to 87%.
اظهر المزيد [+] اقل [-]An extra-virgin olive oil rich in polyphenolic compounds has antioxidant effects in meat-type broiler chickens
2016
Tufarelli, Vincenzo | Laudadio, Vito | Casalino, Elisabetta
The aim of this study was to extend the knowledge on the antioxidant effect of extra-virgin olive oil (EVOO) in the liver of broiler chickens not subjected to any form of insult. A total of 120 male broiler chickens (Hubbard strain) were divided into three groups and fed ad libitum with three isoenergetic diets from hatching until slaughter age (49 days) on a completely randomized design. The dietary treatments consisted of 2.5 % added oil or fat from three sources as follows: diet containing sunflower oil (SFO); diet containing lard (LRD), and diet containing extra-virgin olive oil (EVOO). The activity of the main antioxidative enzymes, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GS-Px) and glutathione S-transferase (GST), and lipid peroxidation as thiobarbituric acid-reactive substances (TBARS) content, was measured in the liver of chickens. The susceptibility to undergo lipid peroxidation was assessed by exposing liver homogenate to 30 °C or to an ascorbate/iron mixture as pro-oxidant system. Dietary oil or fat type improved significantly (P < 0.05) the body weight and gain as well as feed efficiency in birds fed EVOO compared to those fed with the other treatments. Supplementing EVOO in the diet significantly (P < 0.05) reduced lipid peroxidation by increasing antioxidant defense system. These findings, besides adding more results on the antioxidant effect of extra-virgin olive oil on liver of other experimental model other than rats and humans, could be significant for animal welfare, with consequent benefits for both producers and consumers.
اظهر المزيد [+] اقل [-]Could a harmonized tiered approach assess dispersant toxicity in Italy and France?
2020
In recent years, EU countries have recognized national policies to authorize dispersant use to mitigate the petroleum hydrocarbon contamination in case of unintentional oil spills at sea. A harmonization of dispersant approval procedures is needed because the application of different methodologies agrees on dissimilar toxic responses for the same dispersant in different European countries. Actually, different dispersant approval procedures are applied in France and Italy with one French mandatory toxicity test and three Italian bioassays accompanied with different criteria of toxicity classification. In this paper, a harmonized tiered approach is proposed to address the dispersant ecotoxicological assessment in these two nations. Our approach, applicable at the European level, introduces two mandatory tests (algal growth inhibition test and mortality test with crustaceans) and one discretionary test (fish mortality test), by reducing use of vertebrates as much as possible in accordance with humane principles and animal welfare.
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