Effects of lipid emulsions and temperature on the hatchery performance of Chilean scallop Argopecten purpuratus (Lamarck 1819) larvae     

Iker Uriarte  Ana Farías  Jorge M Navarro  Juan Cancino  Gonzalo Gajardo  & Nancy Nevejan 《Aquaculture Research》2003,34(10):899-902

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Coastal geomorphology and oceanographic features shape subtidal benthic communities in management areas of central Chile     

Aldo Hernández  Fabián J. Tapia  Gonzalo S. Saldías  Renato A. Quiñones 《水产资源保护:海洋与淡水生态系统》2021,31(1):126-138

1. The spatial variation in community structure among 30 areas for the management and exploitation of benthic resources (AMEBRs) in central Chile was assessed from surveys conducted during the same spring–summer season. One hundred taxa identified in the subtidal surveys were grouped into 10 functional groups.
2. The influence and relative importance of external factors over benthic associations were assessed through nonmetric multidimensional scaling (NMDS) and path analysis. Three main categories of external factors were considered: ‘terrain traits’ (e.g. coastline exposure), ‘surface-ocean conditions’ (e.g. sea surface temperature, SST), and ‘fishery-related variables’ (e.g. cumulative landings).
3. The NMDS revealed a strong association between benthic community structure and both terrain and surface-ocean conditions (42% of variance explained by permutational multivariate analysis of variance), but not with fishery-related variables. Assemblages typical of rocky substrates were associated with larger seasonal fluctuations in SST and surface chlorophyll a. The presence of soft-bottom functional groups was associated with higher levels of surface fluorescence and larger seasonal fluctuations in a satellite-derived proxy for river-plume influence (nLw645).
4. A path analysis model for hard-bottom communities reached a 49% goodness of fit (GOF), with the presence of epifaunal filter-feeders, grazers, predators, and scavengers being significantly correlated with leathery and corticated foliose algae, which in turn depend on the fraction of rocky substrate in the AMEBR; the fraction of rocky substrate is positively correlated with coastline exposure.
5. The model for soft-bottom communities reached a 52% GOF with the presence of infaunal filter-feeders and epifaunal detritivores depending directly on SST and surface chlorophyll a. The fishery-related variables considered in the model had no apparent effect on the structure of either type of subtidal community.
6. These results provide a hierarchy of physical–biological associations determining the functional composition of subtidal benthic communities in management areas along central Chile. This knowledge may improve future assessments of ecosystem response to changes in environmental conditions and management strategies.

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Reproductive performance and seasonal plasma sex steroid and metabolite levels in a captive wild broodstock of brill Scophthalmus rhombus L.     

Ismael Hachero-Cruzado  Ángel García-López  Marcelino Herrera  Luis Vargas-Chacoff  Gonzalo Martínez-Rodríguez  Juan M Mancera  & José I Navas 《Aquaculture Research》2007,38(11):1161-1174

This study reports egg production by captive wild brill Scophthalmus rhombus, a potential new flatfish species for Southern Europe‐Mediterranean mariculture, as well as seasonal plasma levels of 17β–estradiol, testosterone, 11–ketotestosterone, proteins, triglycerides, glucose and lactate. A mean egg production of 102 800 eggs kg body weight⁻¹ was achieved during the 2005 spawning period (January–March), although a continuous egg supply could only be obtained from some females, which had a higher relative fecundity (261 019±10 393 eggs kg⁻¹) with 12–17 eggs batches released at a mean interval of 3.4 days. Most eggs were obtained with water temperatures ranging from 12 to 14°C, and under increasing temperatures (up to 2.9°C). Potential egg viability (70.1±2.9%), fertilization (72.2±3.4%) and hatching rates (31.9±3.9%) showed high variability, with potential viability tending to decrease as the water temperature increased (mainly between 16 and 17°C) and 0% hatching above 16.6°C. The endocrine changes that brill underwent during late gametogenesis, spawning and postspawning periods were similar to those reported in other Pleuronectiformes. This study establishes an important basis for further research on the biology and physiology of brill reproduction, directed towards the optimization of the breeding techniques used currently.  相似文献   

Long‐term seagrass degradation: Integrating landscape,demographic, and genetic responses     

Pablo Manent  Gonzalo Baolas  Filipe Alberto  Leticia Curbelo  Fernando Espino  Fernando Tuya 《水产资源保护:海洋与淡水生态系统》2020,30(6):1111-1120

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Ontogeny of pepsinogen and gastric proton pump expression in red porgy (Pagrus pagrus): Determination of stomach functionality     

María J. Darias  Harry M. Murray  Jeffrey W. Gallant  Susan E. Douglas  Manuel Yúfera  Gonzalo Martínez-Rodríguez 《Aquaculture (Amsterdam, Netherlands)》2007,270(1-4):369-378

The appearance of functionally developed gastric glands is commonly considered as the transition from the larval to the juvenile stage in fish, since it means the switch from the less efficient alkaline digestion to a more efficient acid digestion characteristic of adult specimens. From that moment, fish are supposedly able to better assimilate nutrients from inert diets. Acid digestion takes place by the action of pepsin activity and hydrochloric acid, both secreted by the gastric glands of the stomach. Pepsinogen is the precursor of pepsin which is converted into active enzyme by the action of hydrochloric acid secreted by the proton pump. The goal of this work was to asses the ontogeny of pepsinogen and gastric proton pump expression along larval development of red porgy using RT-PCR and in situ hybridization techniques. Firstly, red porgy specific pepsinogen and proton pump partial sequences were isolated. Amplification products presented 615 and 591 bp and were identified as pepsinogen IIb and the -subunit of the proton pump (H⁺/K⁺-ATPase) by sequencing, respectively. Both sequences were aligned to several predicted pepsinogen and proton pump polypeptides from different vertebrate species showing elevated homologies with them, especially in the case of the proton pump, the identity of which was never less than 90%. Pepsinogen and proton pump expressions were detected from 30 days post-hatching (dph), increasing with development. Proton pump expression was localized in the gastric glands of red porgy larvae as revealed by in situ hybridization, showing increasing signal intensity along the digestive system development. Such results indicated that at 30 dph red porgy starts to acquire the adult digestive capacity and therefore inert diets should be better utilized from that time onwards.  相似文献   

Effect of water content on thermal behavior of freeze-dried soy whey and their isolated proteins     

Sobral PA  Palazolo GG  Wagner JR 《Journal of agricultural and food chemistry》2011,59(8):3950-3956

Thermal behavior of lyophilized soy whey (LSW) and whey soy proteins (WSP) at different water contents (WC) was studied by DSC. In anhydrous condition, Kunitz trypsin inhibitor (KTI) and lectin (L) were more heat stable for WSP with respect to LSW sample. The increase of WC destabilized both proteins but differently depending on the sample analyzed. Thermal stability inversion of KTI and L was observed for WSP and LSW at 50.0% and 17.0% WC, respectively, which correspond to the same water-protein content mass ratio (W/P ≈ 1.9). At W/P < 1.9, KTI was more heat stable than L. Before the inversion point, WC strongly modified the peak temperatures (T(p)) of KTI and L for WSP, whereas this behavior was not observed for LSW. The high sugar content was responsible for the thermal behavior of KTI and L in LSW under anhydrous condition and low WC. These results have important implications for the soy whey processing and inactivation of antinutritional factors.  相似文献   

Identifying unique populations in long-dispersal marine species: Gulfs as priority conservation areas     

Gonzalo Machado-Schiaffino  Francis Juanes  Eva Garcia-Vazquez 《Biological conservation》2011,(1):330-338

Identification of areas which should be a subject of protection is crucial for safeguarding the marine ecosystems. Amongst the reasons for protecting a region or location, the existence of unique populations or evolutionary significant units for one or more key species is a priority. The North American silver hake, Merluccius bilinearis, is currently managed as two stocks (northern and southern) without considering gulf areas separately. Employing microsatellite and mitochondrial markers we have detected significant F_ST values between hake individuals inhabiting gulfs and those distributed in the open sea, and asymmetric gene flow, higher from the gulf to the open sea than in the opposite direction. These differences can be interpreted as signals of separate populations in gulfs which may act as sources of variability for hake species. Occurrence of similar phenomena in Atlantic waters in both the northern and the southern Hemisphere, for these two pelagic–demersal hake species, suggests that gulfs may constitute a target for designing marine protected areas and confirms the adequacy of gulf-specific management already employed in Argentina.  相似文献   

Cochliomyia hominivorax myiasis in a colony of stray cats (Felis catus Linnaeus, 1758) in Rio de Janeiro, RJ     

Mendes-de-Almeida F  Labarthe N  Guerrero J  Landau-Remy G  Rodrigues DP  Borja GE  Pereira MJ 《Veterinary parasitology》2007,146(3-4):376-378

Cochliomyia hominivorax infestation in domestic cats of an urban colony in the city of Rio de Janeiro is described. The overall prevalence over the period 2001-2005 was 12.5%. Only adult cats were found infested and among these, most cases were observed in males (28%) (p < or = 0.05). The most frequently infested areas of the cats' bodies were the face and nape of the neck. Most lesions were found on the front part of the body of adult males (80%), suggesting that myiasis occur in consequence of competitive fighting wounds.  相似文献   

Residual efficacy of the neonicotinoid insecticide clothianidin against pyrethroid-resistant Aedes aegypti     

Azael Che-Mendoza  Gabriela González-Olvera  Anuar Medina-Barreiro  Carlos Arisqueta-Chablé  Josue Herrera-Bojórquez  Wilberth Bibiano-Marín  Oscar Kirstein  Gonzalo Vazquez-Prokopec  Pablo Manrique-Saide 《Pest management science》2023,79(2):638-644

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Land use and soil carbon accumulation patterns in South African savanna ecosystems     

Gonzalo Almendros  M-Cristina Zancada  M-Teresa Pardo 《Biology and Fertility of Soils》2005,41(3):173-181

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