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Now showing items 1181-1190 of 1209
In vitro and in vivo evaluation of the efficacies of commercial probiotics and disinfectant against acute hepatopancreatic necrosis disease and luminescent vibriosis in Litopenaeus vannamei
(Elsevier, 2024-05)
The bioactivities of two commercially available probiotics and one chemical disinfectant were tested against strains of Vibrio parahaemolyticus (VP<sub>AHPND</sub>) and V. harveyi. This study aimed to determine shrimp pathogenic Vibrios' in vitro and in vivo sensitivities to commercial probiotics and a chemical disinfectant. The probiotics and disinfectant were tested first in vitro, followed by the in vivo trials. Results showed that upon administration of probiotics either through diet or adding into the tank water, the survivability of shrimp was increased during challenge with VP<sub>AHPND</sub> and V. harveyi. Also, the disinfectant was tested against the same pathogens and showed positive bactericidal effects at 2500 ppm and 5000 ppm. The present findings suggest that adding probiotics to the rearing water or the shrimp feeds effectively prevents infection by lowering the load of pathogenic bacteria. In comparison, the effectiveness of the disinfectant (PUR) depends on its appropriate concentration and timing of application. It is not only limited to rearing water but is also applicable for decontaminating pond liners, tanks, and other paraphernalia....
Microbial diversity assessment in milkfish culture ponds
(Sciencedomain International, 2020-02)
Aims: To determine bacterial diversity in milkfish culture ponds that contain different life-cycle stages of the milkfish (pond A: fry, pond B: juveniles and pond C: adults) by DNA sequence analysis of organisms and compare ...
Sandfish (Holothuria scabra) as potential reservoir of white spot syndrome virus (WSSV) when co-cultured with black tiger prawn (Penaeus monodon)
(European Association of Fish Pathologists, 2024-03-08)
Since the first occurrence of White Spot Disease (WSD) in 1992, it is still listed as one of the crustacean diseases by the World Organisation for Animal Health in 2022. Horizontal transmission in co-culture systems is one ...
Subsistence aquaculture and technology transfer among developed and developing countries
(Louisiana State University, 1979-03)
Subsistence-level and small-scale aquaculture systems dominate the aquaculture industry of most developing countires. Characterized by low material and management inputs, low level of technology, and low output, subsistence-level ...
Food colour preference of hatchery-reared juveniles of African catfish Clarias gariepinus
(Elsevier, 2017)
Food colour preference is a fundamental aspect of food recognition and has practical application in the formulation of artificial diets and the design of visual baits. Food colour affects growth performance and feed ...
Utilization of a portable glucometer for the measurement of tissue glucose as a stress indicator in ornamental fish
(Bioflux (Bioflux SRL), 2021)
The stress response in vertebrates is determined by measuring cortisol production following acute or chronic exposure to various environmental stimuli. Cortisol assays as responses to stressful events are done on blood ...
Complete genome sequence of Vibrio parahaemolyticus strain PH1273, isolated from aquacultured shrimp in the Philippines
(American Society for Microbiology, 2023-10-19)
We announce the complete genome sequence of Vibrio parahaemolyticus strain PH1273. This strain was collected from a Penaeus vannamei pond in the Philippines in 2015. Genome analysis revealed that it lacks the gene pirAB ...
Reproduction, early development, and larval rearing of the climbing perch Anabas testudineus (Teleostei: Anabantidae) in captivity
(College of Agriculture and Food Science, University of the Philippines Los Baños, 2023-06)
Induced spawning, early development, and larval rearing of the climbing perch Anabas testudineus were examined under captive conditions. Five female climbing perch [125.33 ± 3.27 mm standard length (SL); 70.67 ± 5.59 g body weight (BW)] were each paired with apparently mature males (108.50 ± 3.97 mm SL; 39.27 ± 4.70 g BW) and induced to spawn with 5,000 IU human chorionic gonadotropin (hCG) + 0.5 mL Ovaprim/kg BW. All hCG + Ovaprim-injected fish spawned 9 – 11 h after hormone administration but saline-injected fish (control group) failed to spawn. Mean egg production per female, fertilization and hatching rates, and larval production per female were 7,667 ± 1,313, 98.11 ± 1.63%, 61.01 ± 19.92%, and 4,435 ± 1,041, respectively. Fertilized eggs (1.52 – 1.96 mm in diameter) were almost spherical, non-adhesive, transparent, and buoyant due to a large, single oil globule (515 ± 33 µm in diameter). First cleavage appeared 30 min post-fertilization (MPF) and egg development lasted for 20 – 24 h post-fertilization (HPF) (29°C). Newly hatched climbing perch larvae [1.73 ± 0.08 mm in total length (TL)] with yolk volume (YV) and oil globule volume (OGV) of 0.545 ± 0.104 mm<sup>3</sup> and 0.072 ± 0.013 mm<sup>3</sup>, respectively had no pigmented eyes or functional mouth parts and digestive tract, and immobile with the yolk sac pointed upward. Eyes became pigmented and both mouth and anus opened in 1 d old larvae (2.09 ± 0.04 mm TL) in preparation for exogenous feeding. Except for body depth (BD) and pre-anal length (PAL), a general increase in TL (1.73 – 3.72 mm), eye diameter (ED) (0.164 – 0.378 mm), head length (HL) (0.205 – 0.923 mm), and mouth gape (MG) size (0.308 – 0.552 mm) was observed, coinciding with yolk resorption in 7 d post-hatched larvae. Climbing perch larvae were reared at four stocking densities (25, 50, 75, 100 larvae L-1) and fed solely on live food (Brachionus rotundiformis from days 2 to 12 and Artemia nauplii from days 13 to 40) or co-fed live food and microparticulate diet (MPD) (Artemia nauplii from days 2 to 15 and Artemia + MPD from days 16 to 40). Mean survival rates at lower densities (25 – 50 larvae L<sup>-1</sup>) were significantly higher than those reared at 75 and 100 larvae L<sup>-1</sup> (P < 0.05). Furthermore, climbing perch larvae co-fed Artemia nauplii and MPD showed better survival (28.67 – 81.00%) than those fed solely on live food (24.88 – 64.00%). However, at the end of the 40 d trial period, growth parameters did not vary significantly among densities (P > 0.05), except for the condition factor in larvae co-fed Artemia nauplii and MPD. Taken together, results demonstrate the effectiveness of hCG + Ovaprim for captive breeding and observations on the early development of climbing perch, and the feasibility of rearing the larvae at 25 – 50 L<sup>-1</sup> on a combination of Artemia nauplii and MPD under laboratory conditions....
Developmental historicity and saccharide heterotrophy of Schizochytrium sp. OT01: Implication of docosahexaenoic acid production for biotechnological applications
(Rushing Water Publishers, 2011)
Thraustochytrids have been targeted worldwide in search of highly oleaginous strains for industrial applications and newly collected holotypes are described based on life cycle developmental history and saccharide heterotrophy. ...
High amorphous poly-beta-hydroxybutyrate (PHB) content in a probiotic Bacillus strain displays better protective effects in Vibrio-challenged gnotobiotic Artemia
(Elsevier, 2018)
In this study, the Bacillus sp. JL47, a superior PHB-accumulating Bacillus strain identified from the previous work, was tested for its protective effects in gnotobiotic Artemia franciscana during a pathogenic Vibrio ...