Comparing the behavioural thermoregulation response to heat stress by Atlantic salmon parr (Salmo salar) in two rivers     

Emily Corey  Tommi Linnansaari  Stephen J. Dugdale  Normand Bergeron  Jean-François Gendron  Michel Lapointe  Richard A. Cunjak 《Ecology of Freshwater Fish》2020,29(1):50-62

Climate change is expected to increase the frequency and magnitude of extreme thermal events in rivers. The Little Southwest Miramichi River (LSWM) and the Ouelle River (OR) are two Atlantic salmon (Salmo salar) rivers located in eastern Canada, where in recent years, water temperatures have exceeded known thermal limits (~23°C). Once temperature surpasses this threshold, juvenile salmon exploit thermal heterogeneity to behaviourally thermoregulate, forming aggregations in coolwater refuges. This study aimed to determine whether the behavioural thermoregulation response is universal across rivers, arising from common thermal cues. We detailed the temperature and discharge patterns of two geographically distinct rivers from 2010 to 2012 and compared these with aggregation onset temperature. PIT telemetry and snorkelling were used to confirm the presence of aggregations. Mean daily maximum temperature in 2010 was significantly greater in the OR versus the LSWM (p = 0.005), but not in other years (p = 0.090–0.353). Aggregations occurred on 14 and 9 occasions in the OR and LSWM respectively. Temperature at onset of aggregation was significantly greater in the OR (T_onset = 28.3°C) than in the LSWM (T_onset = 27.3°C; p = 0.049). Logistic regression models varied by river and were able to predict the probability of aggregation based on the preceding number of hours >23°C (R² = 0.61 & 0.65; P₅₀ = 27.4°C & 28.9°C; in the OR and LSWM respectively). These results imply the preceding local thermal regime may influence behaviour and indicate a degree of phenotypic plasticity, illustrating a need for localised management strategies.  相似文献   

The value of sea urchin,Lytechinus variegatus,egesta consumed by shrimp,Litopenaeus vannamei     

Karen E. Jensen  J. Christopher Taylor  Robert J. Barry  Louis R. D'Abramo  D. Allen Davis  Stephen A. Watts 《Journal of the World Aquaculture Society》2019,50(3):614-621

Sea urchins produce high‐energy, membrane‐bound fecal pellets that contain residual nutrients and large quantities of microbiota. These egesta are readily consumed by the shrimp, Litopenaeus vannamei. Egesta of the sea urchin, Lytechinus variegatus, were evaluated as a feed supplement or total replacement for a commercial shrimp diet. Shrimp were stocked at 0.49 g ± 0.06 g initial body weight and housed individually in 2.8‐L tanks in a commercial recirculating zebrafish system. Shrimp were assigned to one of six diets: commercial shrimp feed, reference sea urchin feed, collected dried sea urchin egesta, collected wet sea urchin egesta, half ration of shrimp feed and half collected wet sea urchin egesta, and egesta naturally produced by two sea urchins in polyculture. Equivalent dry matter amounts of each diet were proffered to shrimp in each treatment twice daily, except for those that had complete access to natural egesta excreted by sea urchins in polyculture. Sea urchins were proffered a reference sea urchin feed at 2% body weight daily. After 27 days, shrimp proffered collected dried or wet egesta did not differ significantly in percent weight gain and showed the lowest weight gain. The percent weight gain of shrimp fed the commercial shrimp diet did not differ significantly from that of the shrimp fed half commercial shrimp diet and half egesta. The highest weight gain was recorded for those shrimp that consumed the untouched egesta produced by sea urchins in polyculture. These data suggest that consumed egesta have noteworthy nutritional value and therefore would be beneficial to the culture of extractive species in an integrated multitrophic aquaculture system.  相似文献   

Cultivation of Agaricus bitorquis mushroom as an strategy for the Integrated Pest Management of the myceliophagous mite Microdispus lambi     

María J Navarro  Francisco R Lpez‐Serrano  Lucía A Escudero‐Colomar  Francisco J Gea 《Pest management science》2020,76(9):2953-2958

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Replacing Soybean Meal with Alternative Protein Sources in Diets for Pond‐raised Hybrid Catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus          下载免费PDF全文

Menghe H. Li  Brian G. Bosworth  Penelope M. Lucas 《Journal of the World Aquaculture Society》2018,49(4):755-760

The present study investigated the replacement of soybean meal with combinations of two or three alternative protein sources in diets for pond‐raised hybrid catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus. Alternative protein sources evaluated included cottonseed meal, distillers dried grains with solubles (DDGS), peanut meal, and porcine meat and bone meal (PMBM). Hybrid catfish fingerlings with a mean initial weight of 35 g/fish were stocked into 25 earthen ponds (0.04 ha) at a density of 14,826 fish/ha. Fish were fed once daily to apparent satiation for 166 d. No significant differences were observed for total diet fed, net yield, weight gain, survival, carcass yield, fillet yield, or fillet proximate composition among dietary treatments. Results show soybean meal may be completely replaced by combinations of cottonseed meal and one or two other alternative protein sources including DDGS, peanut meal, and PMBM in the diet without markedly affecting production and processing characteristics and fillet proximate composition of pond‐raised hybrid catfish. These alternative diets may be used during foodfish production when prices are favorable.  相似文献   

Correction to: Predation on glass eels of Japanese eel <Emphasis Type="Italic">Anguilla japonica</Emphasis> in the Tone River Estuary,Japan     

Yoichi Miyake  Aigo Takeshige  Hikaru Itakura  Hajime Itoh  Hiroaki Onda  Akira Yamaguchi  Akihito Yoneta  Kohma Arai  Yulina V. Hane  Shingo Kimura 《Fisheries Science》2018,84(6):1015-1016

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Still Only One Earth. Progress in the 40 years since the First UN Conference on the Environment. By R.E. Hester & R.M. Harrison (eds). Published by Royal Society of Chemistry,Cambridge, 2015. vii + 285 pp. £67.50. Hardback (ISBN 978‐1‐78262‐076‐1).          下载免费PDF全文

R. L. Hough 《Soil Use and Management》2017,33(1):176-176

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Ornithological importance of artificial ponds: a case study at Kabaklı Pond,south-eastern Anatolia,Turkey     

Recep Karakaş 《Paddy and Water Environment》2017,15(4):919-930

The birds of Kabakl? Pond and its near surrounding were surveyed between October 2014 and December 2015 periods. During the study period, 105 bird species that belong to 12 orders and 34 families were detected and represented. Among these species determined, 17 of them certainly, 19 probably and 11 possibly breed in the area, while 58 of them are wintering or transitory migrating birds for the area. Among the recorded species, seven are globally threatened, while 20 are threatened for Turkey without least concern species. Obtained information suggests that this small artificial area has a great importance for many bird species related to habitat that have. Habitat preferences of species were analysed, and it was determined that the most preferred habitats are pond (water surface), wooded and agricultural zones, respectively. Also, the maximum bird number obtained during April and December, while maximum bird species richness observed during April. Results suggest that artificial ponds can be important for birds as feeding, resting and breeding area due to rapidly decline in natural wetland areas. Effective protection of the area requires the prevention of illegal hunting, fishing, human disturbance and pasturing. Also, in order to extend the existing reed and meadow areas, convenient plantation of natural plants at around of pond has a critic role for waterfowl.  相似文献   

Investigation of the Potential Health Benefits as Lipase Inhibitor and Antioxidant of <Emphasis Type="Italic">Leopoldia comosa</Emphasis> (L.) Parl.: Variability of Chemical Composition of Wild and Cultivated Bulbs     

Mariangela Marrelli  Stefania La Grotteria  Fabrizio Araniti  Filomena Conforti 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(3):274-279

There is a great interest in the nutritional value of vegetables and fruits and how the habitat affects nutritive and biological properties. In vitro studies here reported were performed to evaluate the inhibitory activity of formulations from edible plant on pancreatic lipase. The aim of this study was also to evaluate the biovariability of L. comosa (L.) Parl. bulbs from Italy. The wild bulbs were compared with the same cultivated species that are commonly commercialized to identify samples with the best quality for a potential therapeutic application. Hydroalcoholic extract and polar fraction of wild bulbs showed a very important pancreatic lipase inhibitory activity, with IC₅₀ values of 0.166 ± 0.005 and 0.153 ± 0.005 mg/mL, respectively. In order to characterize the extracts, gas chromatography associated with mass spectrometry (GC/MS) analysis was performed, revealing the predominance of palmitic acid. Phenolic and flavonoid composition was also evaluated. L. comosa extract obtained from wild bulbs demonstrated both antioxidant and anti-obesity activities that might be attributed to a wide range of present phenolic compounds.  相似文献   

Ray blight of pyrethrum in Australia: a review of the current status and future opportunities     

M. A. H. B. Bhuiyan  N. Vaghefi  P. W. J. Taylor 《Plant pathology》2019,68(4):620-627

Ray blight caused by Stagonosporopsis tanaceti is one of the most important diseases of pyrethrum (Tanacetum cinerariifolium), a perennial herbaceous plant cultivated for the extraction of insecticidal pyrethrins in Australia. The disease is responsible for complete yield loss in severe outbreaks. Infected seed is considered as the principal source of S. tanaceti. Infection hyphae remain only in the seed coat and not in the embryo, resulting in pre- and post-emergence death of seedlings and latent infection. Therefore, quantification of the level of infection by S. tanaceti within seed using a qPCR assay is important for efficient management of the disease. Stagonosporopsis tanaceti completes its life cycle within 12 days after leaf infection through production of pycnidia and can infect every tissue of the pyrethrum plant except the vascular and root tissues. Ray blight epidemics occur in pyrethrum fields through splash dispersal of pycnidiospores between adjacent plants. Besides steam sterilization, thiabendazole/thiram and fludioxonil are effective seed-treating chemicals in controlling S. tanaceti before planting begins. Ray blight is currently managed in the field through the foliar application of strobilurin fungicides in the first 1–2 years of crop establishment. Later on, difenoconazole and multisite specific fungicides in the next 2–3 years during early spring successfully reduce ray blight infestation. Avoiding development of resistance to fungicides will require more sustainable management of ray blight including the development and deployment of resistant cultivars.  相似文献   

Replacement of fish oil in plant‐based diets for Pacific white shrimp,Litopenaeus vannamei,by stearine fish oil and palm oil     

Fabio Soller  Luke A. Roy  D. Allen Davis 《Journal of the World Aquaculture Society》2019,50(1):186-203

Stearine fish oil (SFO) and palm oil (PO) have emerged as promising alternatives for the replacement of fish oil (FO) in aquafeeds. This study evaluated the replacement of FO with alternative oils in practical diets for Litopenaeus vannamei. In a clear brackish water study (14.1 g/L) utilizing shrimp (0.29 ± 0.02 g, initial weight), FO was replaced by SFO at inclusion ratios of 100:0, 75:25, 50:50, 25:75, and 0:100 (FO:SFO) and PO as 90% of FO. After 55 days, no significant differences (p < 0.05) in final weight, growth, or survival of shrimp were observed. A second trial (8 weeks) in low‐salinity water (2.1 g/L) with shrimp (0.92 ± 0.02 g, initial weight) evaluated diets with 100% FO, 100% SFO, 90% PO, 90% soybean oil (SO), or 90% flaxseed oil (FXO) as a replacement for FO and four commercially produced diets with 2% of FO, SO, PO, or FXO. One treatment received half rations of the commercial FO diet, and one treatment was based entirely on natural productivity. Results show that the fatty acid profiles of the tail muscle conformed to the lipids of the feed, and highly unsaturated fatty acids (HUFAs) were preserved. Following 8 weeks of culture, there were no significant differences in production performance.  相似文献