Biological Evaluation of Seaweed Composting     

María C. Eyras  Cesar M. Rostagno  Guillermo E. Defossé 《Compost science & utilization》2013,21(4):74-81

Large quantities of green seaweed, linked probably to eutrophication, are cast ashore every summer on the Puerto Madryn beaches (Patagonia, Argentina, 42°S, 65°W). This algal biomass interferes with recreational uses of the beach, and therefore must be periodically collected and disposed. Part of this algal biomass was composted with the objective to produce an amendment to improve physical and nutritional characteristics of some local soils used in intensive horticulture, and at the same time to find a way to reduce environmental pollution. The compost was then biologically evaluated by determining the growth rate of tomato plants cultivated on various substrata (washed sand, sandy loam soil, and sandy loam soil plus inorganic fertilizers) to which different doses of compost were added. Results showed that in all cases the addition of compost increased water holding capacity and plant growth. The increase of tomato plants (Licopersicum esculentum var. platense) was proportional to the compost doses. Also, plants grown on sustrata containing at least ten percent compost had significant benefits compared to control plants, improving growth and water stress resistance. Although the quality of this seaweed compost was limited by excessive amounts of sand and low nitrogen content, it proved to be a good amendment that improved both physical and nutritional characteristics of local sandy loam soils used in intensive horticulture. According to these results, composting is a useful technology both to solve environmental pollution problems and to produce a valuable organic fertilizer for soils.  相似文献   

Pedigree analysis of recaptured fish in the stock enhancement program of spotted halibut Verasper variegatus     

María Del Mar Ortega-Villaizán Romo  Masato Aritaki  Nobuhiko Taniguchi 《Fisheries Science》2006,72(1):48-52

ABSTRACT:   Spotted halibut Verasper variegatus hatchery juveniles produced in 2002 were genotyped using three microsatellite DNA markers (msDNA) and then released into natural waters. Subsequently, recaptured individuals were examined using msDNA. In order to evaluate the effectiveness of the stock enhancement program, from the genetic point of view, a pairwise F _ST test was implemented to estimate the genetic divergence between the wild captive broodstock, the hatchery offspring and the recaptured samples. The analysis showed significant differentiation between the broodstock and recaptured samples. Pedigree determination using msDNA was used to calculate the effective population size of the recaptured stock, which was found to be very low ( N _e ≈ 8). Equal family survivability was observed between the two recaptured stocks, but not between the released and recaptured stock. The number of identified families was higher and more equalized in the hatchery offspring compared to the recaptured samples, where the number of families declined. This fact was caused by an unequal family survivability just before or just after release. Separately, the number of contributing parents to the hatchery offspring was lower than the broodstock census number. Consequently, these two facts caused the genetic divergence of the recaptured stock from the broodstock.  相似文献   

Ex situ growing out of early stages of wild seahorses: Envisioning conservation options for threatened populations     

Diego C. Luzzatto  María L. Estalles 《水产资源保护:海洋与淡水生态系统》2021,31(9):2666-2670

1. Rafting has been proposed as a dispersive mechanism for some species of seahorses. Juvenile Hippocampus patagonicus rafting on the sea surface have been reported. This life stage has high mortality in nature due to ecological and environmental factors usually affecting juvenile planktonic teleosts (e.g. predation).
2. In this study, 50 juvenile seahorses were captured while rafting at the beginning of the reproductive season (December). They were grown out under a standard protocol in a recirculating aquaculture system for 120 days until they reached maturity.
3. During this period, only three seahorses died (6%). Mature seahorses were 65 ± 7 mm average height and showed variable coloration and pigmentation pattern (n = 47; 94%).
4. The availability of juvenile seahorses during the reproductive season and their high survival performance ex situ highlight the feasibility of developing protocols in which juvenile seahorses serve as a novel source of broodstock.

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Spawning aggregation behaviour in the Creole perch,Percichthys trucha (Percichthyidae): A target species for conservation     

María Valeria Fernández  Patricio J. Macchi  Alejandro Sosnovsky  Eduardo E. Zattara  Mailén E. Lallement  Daniela Milano 《水产资源保护:海洋与淡水生态系统》2021,31(11):3248-3260

1. Habitat fragmentation and loss threaten freshwater biodiversity worldwide. Habitats that are essential as fish spawning and nursery sites are critical, and must be identified for conservation purposes. Littoral zones within Patagonian lakes, especially shallow vegetated areas, represent important areas for the Creole perch, Percichthys trucha.
2. Spawning behaviour has been little studied, so it is not known whether these movements are performed in groups. A particular area of a deep lake in northern Patagonia was studied to identify the environmental conditions under which spawning occurs, and to analyse spawning aggregation behaviour in relation to the lunar cycle.
3. To identify spawning sites, spawning occurrence time, and the environmental parameters that determine it, fish capture data were analysed. Underwater cameras were also set up at three depth strata in the shallow zone to detect spawning aggregation behaviour. Aggregation was scored as the greatest number of individuals present in a single frame, and the number present per depth stratum. The relationship between the lunar cycle and Creole perch abundance by depth was then determined.
4. This is the first visual record of a spawning bed and the spawning aggregation behaviour of Creole perch in Patagonian lakes. The abundance of mature Creole perch in the shallow strata during the austral spring suggests that vegetated areas constitute spawning sites. Spawning aggregation takes place at a shallow depth 2 days before the full moon.
5. As the reproductive behaviours of Creole perch are important phenomena in the life history of the species, the results of this study have important implications for conservation and management.

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The content of total mercury and methylmercury in common carp from selected Czech ponds     

Petr Maršálek  Zdeňka Svobodová  Tomáš Randák 《Aquaculture International》2007,15(3-4):299-304

The aim of the present study was to investigate concentrations of total mercury (THg) and methylmercury (MeHG) in the common carp from Czech ponds of Rožmberk, Spolsky, Nezmar, and Velky Bědny. Seven common carps (Cyprinus caprio) from each of the ponds were caught. Muscle tissue, the liver, and the soft and hard roe were used for the tests. Total mercury and methylmercury were found in all the muscle tissue samples examined. Detection limits for total mercury and methylmercury determination methods were 0.001 mg kg^–1 and 0.013 mg kg⁻¹ respectively. Methylmercury levels in the liver and gonads were below the method’s limits of detection. THg and MeHg concentrations in muscle tissues were 0.018–0.063 mg kg^–1 w.w. and 0.019–0.063 mg kg^–1 w.w. respectively. MeHg made up 90–100% of THg in muscle tissues. Total mercury and methylmercury concentrations were significantly (P < 0.05) higher in fish from the Spolsky pond than from the Nezmar pond. MeHg/THg ratios were significantly (P < 0.05) higher in fish from the Rožmberk, Spolsky and Nezmar ponds compared with fish from the Velky Bědny pond.  相似文献   

Evaluation of long-term antibody responses to two inactivated bovine viral diarrhoea virus (BVDV) vaccines     

Ana M. González  Ignacio Arnaiz  Eduardo Yus  Carmen Eiras  María Sanjuán  Francisco J. Diéguez 《Veterinary journal (London, England : 1997)》2014,199(3):424-428

The aim of the present study was to determine the serological response of heifers after vaccination with two inactivated bovine viral diarrhoea virus (BVDV) vaccines by means of various ELISA tests. Three dairy farms were selected from the Galicia region of Spain. In each herd, a batch of heifers to be vaccinated for the first time was selected and followed for 15 months. Heifers from farm 1 (n = 25) were vaccinated with Vaccine A, whereas heifers from farm 2 (n = 16) were vaccinated with Vaccine B. Heifers from farm 3 (n = 17), where no BVDV vaccines were used, acted as controls. Blood samples were analyzed periodically for BVDV antibodies, using five commercial ELISAs, based on BVDV p80 antigen or whole virus.At the end of the study, none of the animals vaccinated with Vaccine A seroconverted according to p80 antibody status, whereas up to 80% tested positive by ELISA against whole virus antigen. For the animals vaccinated with Vaccine B, 2/16 animals seroconverted according to p80 antibody ELISAs, whereas all had seroconverted according to the ELISA against whole virus antigen. In most cases, based on the use of ELISAs to detect specific antibodies against the p80 protein, at 15 months post-vaccination with inactivated BVDV vaccines the responses did not seem to interfere with detection of antibody to BVDV infection. However, the finding of a small proportion of vaccinated animals seropositive against BVDV p80 antigen suggests that antibodies that interfere with diagnosis of BVDV infection within the herd could exist, even when using p80 ELISAs.  相似文献   

Coffee ripeness monitoring using a UAV-mounted low-cost multispectral camera     

Rosas  Jorge Tadeu Fim  de Carvalho Pinto  Francisco de Assis  de Queiroz  Daniel Marçal  de Melo Villar  Flora Maria  Magalhães Valente  Domingos Sárvio  Nogueira Martins  Rodrigo 《Precision Agriculture》2022,23(1):300-318

Coffee beverage quality is highly correlated with the degree of fruit ripeness. In this sense, monitoring fruit ripeness is of utmost importance for harvest planning and, especially for obtaining high-quality beverages. Currently, this process is carried out through manual counts of unripe fruits, which is laborious and limited to a few plants within the field. This study aimed at evaluating the potential of a low-cost multispectral camera for coffee ripeness monitoring in the Zona da Mata region of Minas Gerais State, Brazil. For that, five fields of Arabica coffee with distinct characteristics were evaluated. During the coffee ripeness period, four flights were carried using a Phantom 4 Pro quadcopter equipped with a Mapir Survey 3W camera for imagery acquisition. After that, nine vegetation indices (VIs) were obtained. For the same dates, the percentage of unripe fruits was obtained using an irregular grid in all fields. The data was split into two ripeness classes: suitable for harvest (R) with?<?30% of unripe fruits; and not suitable for harvest (U), with?>?30% of unripe fruits. Then, a principal component analysis was used to infer the importance of the VIs to discriminate plants with unripe fruits from those with ripe fruits. The first two principal components explained?>?75% of the variance in the datasets from all coffee fields. The VIs were able to discriminate the ripeness classes (U and R) in most fields; however, their performance was directly influenced by the crop yield and canopy volume.

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Nodulation competitiveness as a requisite for improved rhizobial inoculants of Trifolium pratense     

Leticia Batista  Pilar Irisarri  Mónica Rebuffo  María José Cuitiño  Juan Sanjuán  Jorge Monza 《Biology and Fertility of Soils》2015,51(1):11-20

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Effect of processing on some chemical and nutritional characteristics of pre-cooked and dehydrated legumes     

Ana María Estévez  Elena Castillo  Fernando Figuerola  Enrique Yáñez 《Plant foods for human nutrition (Dordrecht, Netherlands)》1991,41(3):193-201

The effect of processing on chemical composition and protein quality of three legumes was studied. The species analyzed were beans (Phaseolus vulgaris), Tórtola and Coscorrón varieties; lentils (Lens esculenta), Laird variety; and chick peas (Cicer arietinum), California-INIA variety. The legumes were soaked in a solution of Na₂ EDTA at 0.03% for 16 h and cooked for a predetermined period for each species. They were dried in a tray drier with cross currents of air flowing at a speed of 10 m/min until the residual mositure content was 8%. The water activity in the resulting products ranged from 0.574 to 0.587, thus completely assurring no microbial activity. No important changes were observed in the legumes protein, fat, or fibre contents after processing. The soaking solution was effective in reducing the phytic acid content from 2.99 to 1.64 mg/100 g in the Tórtola beans, which had the highest acid value prior processing. In all the species the heat treatment reduced the activity of the trypsin inhibitors by at least 50%. Cooking and drying significantly increased protein digestibility in all the legumes studied, with chick peas showing the most dramatic increase: from 54.7% pre-processing to 94.9% post-processing. With regard to Net Protein Ratio (NPR), chick peas had a value of 4.03, followed by Tórtola beans (3.29), Coscorrón (3.09) and lentils (2.61). The NPR value for the casein diet was 4.20.  相似文献   

Cytotoxic effect of two legumes in epithelial cells of the small intestine     

Angela Sotelo  María Elena Arteaga  María Inés Frías  María Teresa González-Garza 《Plant foods for human nutrition (Dordrecht, Netherlands)》1980,30(2):79-85

The previously known high toxicity and hemagglutinin concentration found in Escumite bean (Phaseolous acutifolius), widely consumed in the south-east of Mexico, induced us to study the cytotoxic effect of these beans on the epithelial cells of the small intestine of rats. Another, less toxic leguminosae, chick-pea (Cicer arietinum), was used for comparison. In vitro tests showed that the viability of the cells was much more affected by the Escumite bean extract than by the chick-pea extract (P<0.001). The cellularity was much diminished when the epithelial cells were treated with Escumite extract (P<0.001), but not with chick-pea extract. In vivo experiments confirmed these findings. The present results suggest that the deleterious effect of some toxicants present in the raw legume is due to an interaction with intestinal epithelium, which, in turn, may cause a reduced absorption of nutrients.  相似文献