To determine how cerebellar activity influences motor co-ordination, a simple motor act of an electric fish, Eigenmannia spp, was studied. Whenever the fish encounters an object of conductivity different from water, it bends the caudal two-thirds of its body towards the object. This behavior, called "probing", was analysed in the normal fish and in fish with a small cerebellar lesion. Probing could be described as a wave travelling along the body very similar to what one observes when shaking a rope of moderate elasticity. In normal fish, the wave starts at the tipe of the tail and proceeds towards the head, dying out after about two-thirds of the body length. A lesion in the corpus cerebelli causes this wave to start at the head and move towards the tail, though it is otherwise the same as in normal fish, i.e. it has the same frequency components as revealed by Fourier analysis. In addition to the change in probing, the lesioned fish also undulates its body while swimming whereas it is normally kept straight. This undulating wave turns out to be the same as that during probing where it is executed whilst the fish keeps itself on the spot with its locomotory apparatus, the anal fin, which is driven by muscles independent of the trunk muscles used for probing.(ABSTRACT TRUNCATED AT 250 WORDS)
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Curr Microbiol
January 2025
State Key Laboratory of Developmental Biology of Freshwater Fish, Engineering Research Center of Polyploidy Fish Reproduction and Breeding of the State Education Ministry, College of Life Science, Hunan Normal University, Changsha, 410081, People's Republic of China.
Gut mucosal immunity of teleost is mainly governed by mucosa-associated lymphoid tissues (MALT) and indigenous microbiota on mucosal surfaces of gut tract, which can confer protection against pathogenic invasion. However, the probiotic features of bacterial isolates from gut tract of triploid cyprinid fish (TCF) were largely unclear. In this study, Lysinibacillus and Enterobacter strains were isolated for probiotic identification.
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January 2025
Polar branch of the Russian Federal Research Institute of Fisheries and Oceanography ("PINRO" named after N.M. Knipovich), Murmansk, Russia.
More than 27,000 stomachs from 70 species of fish were collected from the Barents Sea in 2015. Quantitative stomach content expressed relative to the body weight of the predator fish (g g as %) varied by four to five orders of magnitude for six species with the largest sample size (Atlantic cod Gadus morhua, haddock Melanogrammus aeglefinus, Greenland halibut Reinhardtius hippoglossoides, long rough dab Hippoglossoides platessoides, polar cod Boreogadus saida, and Atlantic capelin Mallotus villosus). The quantitative stomach contents of individual fish followed a common and strict statistical relationship for predator species or groups of species (by families), and for prey categories across predator species.
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Institute of Agrifood Research and Technology (IRTA), Centre de La Ràpita, Crta. Poble Nou del Delta Km 5.5, 43540, la Ràpita, Spain.
The effect of different feeding habits on gut morphology and digestive function has been intensively studied during the last decades but sympatric closely related fishes are relatively rare objects of such studies. In the present study, we have identified both morphological and physiological changes in the digestive system of a sympatric pair of whitefish represented by "normal" Coregonus lavaretus pidschian (benthivorous) and "dwarf" C. l.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China. Electronic address:
Aquaculture organisms may accumulate metals to induce health risks. Compared with the focus on total contents, chemical-specific risk assessment makes reasonable but is rare. Herein, we elucidated occurrence of twelve metal compounds in shrimp and fish (edible muscle, one of major metal-containing and generally targeted organs), water, sediment, and feedstuff from two aquaculture ponds in Zhejiang Province (one of the major aquatic production and consumption areas).
View Article and Find Full Text PDFPoult Sci
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Ancera, Inc, Branford, CT 06405, USA. Electronic address:
Necrotic enteritis (NE), caused by the gram-positive, anaerobic bacterium, Clostridium perfringens, results in an estimated $6 billion in annual economic losses to the global poultry industry. C. perfringens is part of the normal microflora of the poultry gastrointestinal tract, but damage to the intestinal epithelium can lead to increased cell proliferation and production of toxins which gives rise to disease.
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