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551.
Filippo Barbanera Oliver R.W. Pergams Giovanni Forcina Fernando Dini 《Biological conservation》2010,143(5):1259-1268
Introduction of wildlife for game restocking is one major pathway of genetic homogenization. The red-legged partridge (Alectoris rufa, Phasianidae), a small game bird native to south-western Europe, is in high demand by hunters and natural populations are constantly supplemented by commercial stocks of captive-bred individuals. Also, in recent years human-mediated hybridization with congeneric chukar partridges (Alectoris chukar: Greece, Cyprus, from Middle East to East Asia) has been frequently documented in the wild and in captivity. This study attempts to evaluate the genetic consequences of intensive captive breeding and restocking in the A. rufa species. We investigated A. rufa genetic diversity by making comparisons in both a spatial (across the entire species’ range) and a temporal framework. We accomplished this latter by comparing modern vs. ancient partridges resident in museums and collected 1856-1934, well before supplemental stocking became common. Using mtDNA we found significant changes in the haplotype profile of modern vs. ancient A. rufa, and widespread introgression with chukar genes across the entire species range only in modern representatives, with the relevant exception of Corsican populations. However, Random Amplified Polymorphic DNA (RAPD), as opposed to microsatellite DNA markers, showed also modern Corsican populations to harbour many A. rufa × A. chukar hybrids. We conclude that captive breeding programs should make strict use of time-saving and comparatively low cost DNA barcodes to minimize genetic pollution, such as those provided by diagnostic RAPD markers. We also recommend that the active ban on import of exotics and/or hybrids be extended to non-local populations. Altogether this would represent a substantial step forward to preserve A. rufa as well as other game species subjected to similar intensive management. 相似文献
552.
In carnivorous fish species, zooplankton is one of the main food items in the early life stages and some fish species continue feeding on such food items further along the life stages even in the farming environment. In this study, the intake of natural food items was assessed in juvenile pirarucu Arapaima gigas reared in earthen ponds. Juvenile pirarucu (12.2 ± 4.32 g and 12.1 ± 1.13 cm) were stocked in fertilized earthen ponds (240 m²). For the analysis of the fish stomach content and plankton in the pond water, the fish and pond water were sampled weekly for 75 days and biweekly until the fish reached a mean weight of 750 g. Although artificial feed was used, pirarucu also ingested the natural food available in the pond water. Among the zooplankton, pirarucu demonstrated feeding preference for cladocerans despite the abundance of rotifers and copepods. Cladocerans were present in more than 80% of the stomach contents of fish up to 300 g and in 65%, 45% and 17% of fish of 301–500 g, 501–700 g and 701–900 g respectively. Copepods were present only in fish up to 500 g at low abundance. High ingestion of insects and plant material was observed in the stomach content of fish of all size classes. The results demonstrate that juvenile pirarucu ingest natural food available in the farming pond and suggests that the adoption of pond fertilization practices may have positive effects on fish growth performance. 相似文献
553.
Identification and characterization of proteases from skin mucus of tambacu,a Neotropical hybrid fish 总被引:1,自引:0,他引:1
C. M. C. Salles P. Gagliano S. A. T. Leitão J. B. Salles H. L. M. Guedes V. P. F. Cassano S. Giovanni De-Simone 《Fish physiology and biochemistry》2007,33(2):173-179
Skin secretions of fishes constitute a rich source of proteins with a broad spectrum of antimicrobial properties. We report
here the characterization of proteases from skin mucus of tambacu, an economically important Neotropical hybrid fish. The
effects of pH on the proteolytic activities of the mucus acting on various substracts – hemoglobin, casein, bovine serum albumin
(BSA) and ovalbumin (OVA) – were tested. Optimal pH values for protease activity on hemoglobin were 4.5 and 8.5, on casein,
8.5, on BSA, 5.0 and 7.5, and on ovalbumin, 4.5 and 6.5. The proteolytic activity was inhibited on all of these substrates
in the presence of specific inhibitors: caseinolytic activity was inhibited by inhibitors of serine and metalloproteases;
hemoglobinolytic activity was inhibited by serine, aspartic and metalloproteases inhibitors; albuminolytic activity on BSA
was inhibited by serine and aspartic proteases inhibitors, and on ovalbumin, by cysteine and aspartic proteases inhibitors.
Gelatin zymography revealed that the skin mucus of tambacu consisted primarily of serine and metalloproteases. Hemoglobin
zymography showed one proteolytic band inhibited by EDTA, whereas casein zymography showed two proteases inhibited by serine
proteases inhibitors. We were able to identify all classes of proteases in the mucus from the skin of tambacu. These, and
these results suggest that the proteolytic activities of the skin mucus of fish may play an important role in the defense
against microorganisms and ectoparasites. 相似文献
554.
Giacomo Fais Alessia Manca Federico Bolognesi Massimiliano Borselli Alessandro Concas Marco Busutti Giovanni Broggi Pierdanilo Sanna Yandy Marx Castillo-Aleman Ren Antonio Rivero-Jimnez Antonio Alfonso Bencomo-Hernandez Yendry Ventura-Carmenate Michela Altea Antonella Pantaleo Gilberto Gabrielli Federico Biglioli Giacomo Cao Giuseppe Giannaccare 《Marine drugs》2022,20(5)
Spirulina is the most studied cyanobacterium species for both pharmacological applications and the food industry. The aim of the present review is to summarize the potential benefits of the use of Spirulina for improving healthcare both in space and on Earth. Regarding the first field of application, Spirulina could represent a new technology for the sustainment of long-duration manned missions to planets beyond the Lower Earth Orbit (e.g., Mars); furthermore, it could help astronauts stay healthy while exposed to a variety of stress factors that can have negative consequences even after years. As far as the second field of application, Spirulina could have an active role in various aspects of medicine, such as metabolism, oncology, ophthalmology, central and peripheral nervous systems, and nephrology. The recent findings of the capacity of Spirulina to improve stem cells mobility and to increase immune response have opened new intriguing scenarios in oncological and infectious diseases, respectively. 相似文献
555.
Simone Savoia Andrea Albera Alberto Brugiapaglia Liliana Di Stasio Alessio Cecchinato Giovanni Bittante 《畜牧与生物技术杂志(英文版)》2021,(3):1214-1225
Background:The possibility of assessing meat quality traits over the meat chain is strongly limited, especially in the context of selective breeding which requi... 相似文献
556.
- Group membership is a key attribute of animal societies and central to the study of social structure in several taxa. However, social structure analyses are sensitive to the way data are collected and associations defined.
- In this study, a time–space method was used to investigate the social structure of common bottlenose dolphins Tursiops truncatus observed and photographed across 7 years in the semi-enclosed Gulf of Corinth, Greece. Instead of adopting traditional group definitions, individuals were considered as being members of the same group if photographed within a specific time and space window. This approach can be applied post hoc across studies and can offer advantages under challenging sampling conditions (e.g. when dealing with groups spread over vast areas or when group membership is otherwise hard to assess).
- Dolphins were mostly found around coastal cage aquaculture facilities farming European sea bass Dicentrarchus labrax and gilthead seabream Sparus aurata.
- Dolphins formed clusters largely or entirely composed of individuals of the same sex, suggestive of sex-based homophily. Habitat partitioning was not detected: there was substantial spatial overlap among dolphin clusters, with all individuals using a relatively small area in the northern portion of the Gulf, where most of the productive fish farms were located. Associations between females were stronger than those between males, and daughters tended to stay in the group of their mothers.
- Sex-based social clustering may allow females and calves to limit interactions with potentially aggressive males, while individuals of both sexes benefit from prey concentrated around fish farms.
- Adaptation to foraging around farms can result in trade-offs between the costs and benefits of nourishment and social interaction. This may have both positive or negative effects on the animals that should be considered in the context of ensuring their favourable conservation status.