Trophic ecology and diet of Hydra vulgaris (Cnidaria; Hydrozoa)

2017 ◽  
Vol 67 (3-4) ◽  
pp. 287-300 ◽  
Author(s):  
María I. Deserti ◽  
Karina S. Esquius ◽  
Alicia H. Escalante ◽  
Fabián H. Acuña
Keyword(s):  
Nutritional Value ◽  
Trophic Ecology ◽  
Buenos Aires ◽  
Feeding Habits ◽  
Natural Habitat ◽  
Buenos Aires Province ◽  
Hydra Vulgaris ◽  
Natural Diet ◽  
Food Items ◽  
Invertebrate Prey

Hydra is a genus of common, sessile, solitary freshwater cnidarians, which are defined as carnivorous and efficient predators. The purpose of this study was to obtain information on the feeding habits and diet of Hydra vulgaris collected from its natural habitat in Nahuel Rucá Lake (Buenos Aires Province, Argentina). We found three categories of food items in the coelenteron: algae, fungi, and small invertebrates. Algae dominated the diet in terms of abundance and frequency of occurrence, but their volumetric contribution was almost negligible, as was their possible nutritional value. Invertebrate prey captured, using active predation, represented the major volumetric contribution, with four different taxa found. The detection of phytoplankton in the gastral cavities reveals the input of some organisms present in the surrounding waters in addition to the invertebrates. This information is novel, since studies on the natural diet of Hydra are very scarce.

scholarly journals Trophic ecology of Mugil liza at the southern limit of its distribution (Buenos Aires, Argentina)

2015 ◽  
Vol 63 (3) ◽  
pp. 271-277 ◽  
Author(s):  
Gustavo Thompson ◽  
Roberta Callico Fortunato ◽  
Ignacio Chiesa ◽  
Alejandra Volpedo
Keyword(s):  
Trophic Ecology ◽  
Buenos Aires ◽  
Feeding Habits ◽  
Stomach Contents ◽  
Benthic Fauna ◽  
Fine Sand ◽  
Coarse Sand ◽  
Buenos Aires Province ◽  
Southern Limit ◽  
Rates Of Growth

AbstractIn order to get to know the habitat and feeding habits of Mugil liza on the southern coast of Buenos Aires province, 65 specimens obtained at two sampling sites - the San Blas bay (SBB) and the mouth of the Quequén-Salado river (QSR) - during spring (November 2012) and summer (February 2013) were analyzed. Specimens were measured, sexed and weighed, their stomachs were removed and their stomach contents weighed and analyzed under the stereoscopic microscope. The specimens were adults, 28-49 cm in length and weighing 380-1100 g. Population growth was higher in the SBB (TW: 0.003*TL3.36), than in RQS (TW: 0.045*TL2.61). About 98% of the stomachs had some content, their repletion rate being of between 0.4 and 1.2%. About 75% of the stomachs contained very fine sand with few benthic organisms (algae, copepods, foraminifera), whereas the remaining 25% of stomachs contained coarse sand and a greater presence of benthic fauna (amphipods, bivalves, gastropods and coral organisms). The linear relationship between the weight of stomach contents and the total weight and length of the fish showed that the rates of growth (slope) were the same at both sites, but intercept values were significantly higher for San Blas bay (test parallelism; p < 0.001).

scholarly journals Natural diet and feeding habits of a freshwater prawn (Macrobrachium carcinus: Crustacea, Decapoda) in the estuary of the Amazon River

2014 ◽  
Vol 44 (2) ◽  
pp. 235-244 ◽  
Author(s):  
Jô de Farias Lima ◽  
Jamile da Silva Garcia ◽  
Thibério Carvalho da Silva
Keyword(s):  
Feeding Habits ◽  
River Estuary ◽  
Stomach Contents ◽  
Freshwater Prawn ◽  
Amazon River ◽  
Feeding Preferences ◽  
Important Food ◽  
Natural Diet ◽  
Food Items ◽  
Stomach Analysis

Macrobrachium carcinus is a Brazilian native prawn with recognized potential for use in aquaculture activities. However, there is little information about the natural diet and feeding habits of this species. The aim of this study was the identification of the diet items of M. carcinus based on the analysis of the stomach contents. Specimens were collected in the Amazon River estuary between January 2009 and January 2010. The stomach analysis was carried out by using the frequency of occurrence (FO), methods of points (MP) and feeding index (FI). It was observed that prawns fed on detritus, animals and plant fragments as the most important food items. Sediment accounted for the main stomach content, accounting for 43.2% by the MP, 44.9% by FI and 100% by the FO. Sexual differences in feeding preferences were not found in this study, and seasonal differences in the frequency of items ingested by M. carcinus were not observed. The results indicated that M. carcinus can be considered omnivorous species, but with an important carnivorous component, similar to that found in other Macrobrachium species.

Occurrence of Cryptosporidium and other enteropathogens and their association with diarrhea in dairy calves of Buenos Aires province, Argentina

2021 ◽  
Vol 24 ◽  
pp. 100567
Author(s):  
Carlos J. Garro ◽  
Gabriel E. Morici ◽  
Mariela L. Tomazic ◽  
Daniel Vilte ◽  
Micaela Encinas ◽  
...  
Keyword(s):  
Buenos Aires ◽  
Dairy Calves ◽  
Buenos Aires Province

scholarly journals Water Footprint and Virtual Water Trade of Maize in the Province of Buenos Aires, Argentina

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1769
Author(s):  
Maria Macarena Arrien ◽  
Maite M. Aldaya ◽  
Corina Iris Rodriguez
Keyword(s):  
Buenos Aires ◽  
Water Footprint ◽  
Local Level ◽  
Virtual Water ◽  
Buenos Aires Province ◽  
Pollution Load ◽  
Basin Scale ◽  
Water Volumes ◽  
Water Scarce ◽  
First Time

Agriculture is the largest fresh water consuming sector, and maize is the most produced and consumed crop worldwide. The water footprint (WF) methodology quantifies and evaluates the water volumes consumed and polluted by a given crop, as well as its impacts. In this work, we quantified for the first time the green WF (soil water from precipitation that is evapotranspired) and the green virtual water exports of maize from Buenos Aires province, Argentina, during 2016–2017, due to the relevance of this region in the world maize trade. Furthermore, at local level, we quantified the green, blue (evapotranspired irrigation), and grey (volume of water needed to assimilate a pollution load) WF of maize in a pilot basin. The green WF of maize in the province of Buenos Aires ranged between 170 and 730 m3/ton, with the highest values in the south following a pattern of yields. The contribution of this province in terms of green virtual water to the international maize trade reached 2213 hm3/year, allowing some water-scarce nations to ensure water and water-dependent food security and avoid further environmental impacts related to water. At the Napaleofú basin scale, the total WF of rainfed maize was 358 m3/ton (89% green and 11% grey) and 388 m3/ton (58% green, 25% blue, and 17% grey) for the irrigated crop, showing that there is not only a green WF behind the exported maize, but also a Nitrogen-related grey WF.

Structural and metamorphic evolution of the Sierras Australes (Buenos Aires Province/Argentina)

1990 ◽  
Vol 79 (3) ◽  
pp. 797-821 ◽  
Author(s):  
W. von Gosen ◽  
W. Buggisch ◽  
L. V. Dimieri
Keyword(s):  
Buenos Aires ◽  
Buenos Aires Province ◽  
Metamorphic Evolution
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