Latin american journal of aquatic research vol. 50 num. 3 lang. en
- Heavy metals in macroinvertebrates (Penaeus) in the Mexican coasts of the Gulf of Mexico: status, sources, and regulationsel septiembre 27, 2022 a las 8:20 am
ABSTRACT The present work analyzes the current situation of scientific research on heavy metals and current regulations in macroinvertebrates (Penaeus) from the coastal region of the Gulf of Mexico. Its association with public health was identified based on national and international permissible limits for this fishery resource. The research analysis identified a high percentage of studies that report concentrations within the permissible limits established by the Mexican Official Standards and European regulations, reflecting a high percentage of consumption of this fishery resource that does not represent a risk to public health. However, specific cases exceeded national and international concentration limits, which justifies the importance of monitoring this fishery resource with emphasis on compliance with current regulations, supporting the need to redefine regulatory policies to address the current situation. Likewise, it is important to quantify these metals in a homogeneous, systematic, and continuous way to contrast the different studies on macroinvertebrates as environmental health bioindicator organisms and to know the distribution of these pollutants in the ecosystems inhabited by this important fishery resource.
- What do we know about sea turtle fibropapillomatosis studies in the American continent? A bibliographic reviewel septiembre 27, 2022 a las 8:20 am
ABSTRACT Fibropapillomatosis (FP) is a debilitating neoplastic infectious disease that affects sea turtles globally. Researchers on the American continent have generated valuable information about FP that can serve as the current source of biological knowledge on the disease, but this information is scattered throughout many scientific journals, books, thesis, and conference proceedings. Through a systematic literature review, the present study intends to summarize the current state of knowledge available on the American continent and highlight the knowledge gaps regarding FP in sea turtles. We reviewed 192 studies published from 1938 to 2021 performed on the American continent. The maximum annual number of publications occurred in 2019 with 15 publications, and there is an increasing trend in studies published over the past 25 years. One hundred thirty studies were performed in North America, 43 in South America, 14 in the Caribbean region, and 5 in Central America. The USA, Brazil, and Mexico were the most productive countries for FP research. The main topics addressed were pathological findings, records/incidences of FP, and molecular characterization. The most studied species with FP is the green turtle (Chelonia mydas). Our results show a lack of geographical information about FP, particularly in the Central American region and the Pacific coast of South America. While there has been a significant increase in FP knowledge in the last two decades, most of the studies focused on pathological findings, while viral replication and transmission of this disease remains unknown, highlighting the need for studies that describe immune characteristics, stressful environmental conditions, or disorders in blood chemical values in organisms affected by FP.
- Diet of the land vegetable Lactuca sativa as an alternative to macroalgae for the growth of juvenile the sea urchin Loxechinus albus in northern Chileel septiembre 27, 2022 a las 8:20 am
ABSTRACT The sea urchin Loxechinus albus is of great commercial value due to its nutritional content. The main diet of the urchin in the north of Chile in its natural habitat is the macroalgae Ulva lactuca. This work evaluated the growth of L. albus juvenile fed diets based on vegetable lettuce Lactuca sativa and macroalgae Ulva sp. Ingestion, growth, survival, and proximal analysis of the diets were registered for 13 weeks. At the end of the experience (90 days), no mortality and greater consumption of L. sativa were observed. In the proximal analysis, L. sativa presented the highest percentage (lipids, proteins, ashes, carotenoids, chlorophyll). The greatest growth and weight gain were observed with the Ulva sp. diet. Finally, the incorporation of L. sativa in the diets of urchins would imply a supplement of minerals and carotenoids, so we propose the addition of this lettuce as a nutritional supplement during the first stage of the cultivation of the L. albus.
- Siphonophore community biodiversity and spatio-temporal distribution concerning the oceanographic parameters in the Patagonian Fjord Ecosystem during the winter seasonel septiembre 27, 2022 a las 8:20 am
ABSTRACT This study describes the spatial distribution and abundance of siphonophores concerning oceanographic variables (temperature, salinity, and dissolved oxygen) in the northern Chilean Patagonian Fjord Ecosystem, from Guafo Passage (43°30’S) to Elefantes Gulf (46°40’S) during the winter of 2012. Twelve species were identified, ten belonging to suborder Calycophorae and two assigned to suborder Physonectae. The species Chelophyes appendiculata and Sphaeronectes gamulini are new records for this study area. Dominant species were Muggiaea atlantica (63.15%), Lensia conoidea (21.85%), and Sphaeronectes koellikeri (9.91%). Species richness showed a negative latitudinal gradient, and the highest densities were found in North Moraleda Channel (5316 ind 1000 m-3) and the lowest in South Moraleda Channel, near Elefantes Gulf (71 ind 1000 m-3). Some species showed a significant and positive association with some oceanographic variables, e.g., M. atlantica showed a positive association with dissolved oxygen, L. conoidea with temperature and negative association with dissolved oxygen, Sphaeronectes fragilis, S. koellikeri, and C. appendiculata showed a positive association with salinity. Eudoxids (sexual reproductive stage) were found for M. atlantica, L. conoidea, and Dimophyes arctica, indicating that the PFE conditions are suitable for some siphonophore species even in winter.
- Effects of highly-diluted bioactive compounds (HDBC) on growth, survival and physiological condition of Penaeus vannamei shrimp reared in a commercial farmel septiembre 27, 2022 a las 8:20 am
ABSTRACT This study evaluates the application of highly-diluted bioactive compounds (HDBC) as an alternative to improve the white shrimp Penaeus vannamei performance reared during a semi-intensive commercial-scale production cycle (130 days) in arid environmental conditions. The effects of HDBC were analyzed on productive performance, enzyme activity, and energy reserves associated with the nutritional condition. Six 10-ha earthen ponds were used. Two experimental HDBC treatments and one control treatment were evaluated: [T1 = PhA+SiT (phosphoric acid 7C and Silicea terra 7C); T2 = PaV+ViT (Passival® 7C and Vidatox® 31C); T3 = Control (No HDBC)], using 2 ponds × 3 treatments = 6 ponds. Three shrimp samples were taken (S1, S2, S3) at 7, 52, and 130 days. The results indicated that organisms from T2 significantly increased in several productive indicators, such as weight gain, daily weight gain, specific growth rate, total length, feed efficiency, and productive performance. T2's bioactive compounds ingested with the pelleted feed and present in the gut -even at highly diluted concentration- improved energetic reserves, such as lipids in the hepatopancreas and digestive enzyme activity, enhancing the physiological status of shrimp farmed under semi-intensive rearing conditions, suggest that HDBC used in this study could have a beneficial and eco-friendly impact on commercial-scale shrimp production.