scholarly journals Effects of water pH on susceptibility of whiteleg shrimp (Litopenaeus vannamei) to acute hepatopancreatic necrosis disease Vibrio parahaemolyticus

2019 ◽  
Vol 02 ◽  
pp. 88-96
Author(s):  
Tuan V. Vo
Keyword(s):  
Litopenaeus Vannamei ◽  
Respiratory Burst ◽  
Vibrio Parahaemolyticus ◽  
Low Ph ◽  
Water Levels ◽  
Cumulative Mortality ◽  
High Ph ◽  
Significant Difference ◽  
Water Ph ◽  
Acute Hepatopancreatic Necrosis Disease

Effect of water pH on susceptibility of whiteleg shrimp Litopenaeus vannamei to acute hepatopancreatic necrosis disease caused by Vibrio parahaemolyticus was carried out in laboratory condition. White leg shrimp (2 - 3 g) were challenged by immersion for 2 h with tryptic soy broth (TSB)-grown Vibrio parahaemolyticus at 10 times lower dose of LD50. The results showed that the cumulative mortality of V. parahaemolyticus-immersed shrimp after 240 h was increased from low to high pH water levels (23.3 ± 5.8% in pH 6.3; 30.0 ± 20.0% in pH 7.3; 86.7 ± 15.3 in pH 9.3, respectively). The cumulative mortality of shrimp that held in pH = 8.3 was the lowest (20.0 ± 0.0%). In another experiment, immune parameters such as total haemocytes count and respiratory burst of Litopenaeus vannamei held at different pH levels were examined at 0, 24, 48, 72 and 96 h. The results indicated that no significant difference of total haemocytes count was observed at different pH water levels (pH 6.3, 7.3, 8.3, 9.3) at 0 - 72 hpc (hour post challenge). At 96 hpc, total haemocytes count at high pH water level (9.3) was increased and significant difference in comparison with the total haemocytes count recorded in low pH water levels (6.3, 7.3, 8.3). Respiratory burst was also not different at different pH water levels at 0 hpc. However, respiratory burst of shrimp that held at low pH water levels (pH 6.3 and 7.3) was rapidly reduced and significant difference in compared with the shrimp that held in high pH water levels (pH 8.3 and 9.3). It was therefore concluded that low and high pH stress decrease the resistance of Litopenaeus vannamei against V. parahaemolyticus and decrease several parameters of the immune response.

scholarly journals Probiotic modulation of the gut bacterial community of juvenile Litopenaeus vannamei challenged with Vibrio parahaemolyticus CAIM 170

2017 ◽  
Vol 43 (4) ◽  
pp. 766-775
Author(s):  
Irasema E. Luis-Villaseñor ◽  
Domenico Voltolina ◽  
Bruno Gomez-Gil ◽  
Felipe Ascencio ◽  
Ángel I. Campa-Córdova ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Litopenaeus Vannamei ◽  
Vibrio Parahaemolyticus ◽  
Single Strand Conformation Polymorphism ◽  
Positive Control ◽  
Negative Control ◽  
Rrna Gene ◽  
Protective Effects ◽  
Probiotic Treatment ◽  
Significant Difference

The protective effects of two probiotic mixtures was studied using the fingerprints of the bacterial community of Litopenaeus vannamei juveniles exposed to probiotics and challenged with Vibrio parahaemolyticus CAIM 170. Fingerprints were constructed using 16S rRNA gene and the PCR-SSCP (Single strand conformation polymorphism) technique, and the probiotics used were an experimental Bacillus mixture (Bacillus tequilensis YC5-2 + B. endophyticus C2-2 and YC3-B) and the commercial probiotic Alibio. The DNA for PCR-SSCP analyses was extracted directly from the guts of shrimps treated for 20 days with the probiotics and injected with 2.5×105 CFU g-1 of V. parahaemolyticus one week after suspension of the probiotic treatment. Untreated shrimps served as positive (injected with V. parahaemolyticus) and negative (not injected) controls Analysis of the bacterial community carried out after inoculation and 12 and 48 h later confirmed that V. parahaemolyticus was present in shrimps of the positive control , but not in the negative control or treated with the probiotic mixtures. A significant difference in the diversity of the bacterial community was observed between times after infection. The band patterns in 0-12 h were clustered into a different group from that determined after 48 h, and suggested that during bacterial infection the guts of whiteleg shrimp were dominated by gamma proteobacteria represented by Vibrio sp. and Photobacterium sp. Our results indicate that the experimental and the commercial mixtures are suitable to modulate the bacterial community of L. vannamei and could be used as a probiotic to control vibriosis in juvenile shrimp.

scholarly journals Effects of water pH on physiological parameters and color changes of Asian Bumblebee Catfish (Pseudomystus siamensis Regan, 1913)

2019 ◽  
Vol 02 ◽  
pp. 78-87
Author(s):  
Tuan V. Vo
Keyword(s):  
Blood Cells ◽  
Color Change ◽  
White Blood Cells ◽  
Physiological Parameters ◽  
Water Levels ◽  
Cumulative Mortality ◽  
Color Changes ◽  
Water Ph ◽  
Mortality Ratio ◽  
Set Up

Effects of water pH on blood physiological parameters and color change of Asian bumblebee catfish (Pseudomystus siamensis) (4 – 6 g/fish) were carried out in laboratory condition. The experiment was set up in 8 weeks at different pH water levels (pH = 3, 4, 5, 6, 7, 8, 9, 10, 11). The results have shown that the cumulative mortality ratio of Asian bumblebee catfish at the end of 24 h challenge was 100% at pH = 11, 70.83% at pH = 10, and 62.5% at pH = 3. No mortality of fish was observed at pH = 4, 5, 6, 7, 8, 9 after 24 h of the challenge. The lowest and highest pH threshold that killed 50% of fish after 24 h of the challenge were 3.04 and 9.95, respectively. After 24 h of the challenge, total number of red and white blood cells of fish increased at pH = 3, 9, 10, and get the highest level at pH = 3 (1.87 × 106 cells/mm3 and 1.59 × 105 cells/mm3, respectively. At the end of the challenge, highest number of red and white blood cells were observed at pH = 8 (2 ± 0.23 × 106 cells/mm3 and 1.27 ± 0.26 × 105 cells/mm3, respectively). Fish were in bright and beautiful color when cultured in high pH water levels.

scholarly journals ANTIBACTERIAL ACTIVITY OF HERBAL EXTRACTS AGAINST Vibrio parahaemolyticus CAUSING ACUTE HEPATOPANCREATIC NECROSIS DISEASE (AHPND) IN WHITELEG SHRIMP (Litopenaeus vannamei) IN VITRO

2020 ◽  
Vol 1 (38) ◽  
pp. 82-88
Author(s):  
Nguyen Thi Nguyen ◽  
Nhi Thi Hong Nguyen
Keyword(s):  
Antibacterial Activity ◽  
Litopenaeus Vannamei ◽  
Vibrio Parahaemolyticus ◽  
Leaf Extract ◽  
Herbal Extracts ◽  
Physalis Angulata ◽  
Whiteleg Shrimp ◽  
Acute Hepatopancreatic Necrosis Disease ◽  
Muntingia Calabura

The antibacterial activity of herbal extracts to Vibrio parahaemolyticus causing acute hepatopancreatic necrosis disease in whiteleg shrimp (Litopenaeus vannamei) was studied and carried out in the School of Agriculture and Aquaculture, Tra Vinh University. The results showed that the inhibition zone of Muntingia calaburaleaf extract with ethanol 70% was 18.00 ± 0.00mm, Muntingia calabura leaf extract with ethanol 90% was 17.33 ± 0.58 mm and Muntingia calabura fresh leaf extract was 13.00 ± 0.00 mm. Minimum inhibitory concentration (MIC) of Muntingia calabura leaf extract with ethanol 70% and 90% were 5.120 mg/L, 10.240 mg/L. MIC value of Al lium cepa extract with ethanol 70% and 90% were 40.960 mg/L, Physalis angulata extract with ethanol 70% and 90% were 81.920 mg/L. The results showed that the antimicrobial activity was highest in the Muntingiacalabura leaf extract and lowest in Physalis angulata extract.

THE EFFECT OF VARYING WATER pH ON THE ACIDIFICATION OF EXPIRED WATER IN RAINBOW TROUT

1990 ◽  
Vol 149 (1) ◽  
pp. 149-160 ◽  
Author(s):  
HONG LIN ◽  
D. J. RANDALL
Keyword(s):  
Carbon Dioxide ◽  
Rainbow Trout ◽  
Low Ph ◽  
Ammonium Ion ◽  
Dominant Effect ◽  
High Ph ◽  
Ion Formation ◽  
Water Ph

Acidification of expired water was studied in rainbow trout exposed to water of pH9.91, 6.80 (control) and 3.88. For the high-pH and the control exposures, the water flowing over the gills was acidified because of the dominant effect of CO2 hydration. During the low-pH treatment, the water was alkalized because of ammonium ion formation and perhaps bicarbonate dehydration. Carbon dioxide excretion was not significantly affected by the high-pH and low-pH treatments but ammonia accumulated in the plasma in both cases.

scholarly journals NGHIÊN CỨU KHẢ NĂNG KHÁNG VI KHUẨN Vibrio spp. GÂY BỆNH HOẠI TỬ GAN TỤY CẤP (AHPND) TRÊN TÔM CHÂN TRẮNG (Litopenaeus vannamei) CỦA DỊCH CHIẾT TỪ CÂY CHÓ ĐẺ THÂN XANH (Phyllanthus amarus Schum)

2019 ◽  
Vol 128 (1E) ◽  
pp. 99-106
Author(s):  
Trần Vinh Phương ◽  
Hoàng Thị Ngọc Hân ◽  
Đặng Thanh Long ◽  
Phạm Thị Hải Yến ◽  
Nguyễn Quang Linh
Keyword(s):  
Litopenaeus Vannamei ◽  
Vibrio Parahaemolyticus ◽  
Early Mortality ◽  
Phyllanthus Amarus ◽  
Early Mortality Syndrome ◽  
Acute Hepatopancreatic Necrosis Disease ◽  
Vibrio Spp

Kết quả nghiên cứu nhằm xác định khả năng kháng khuẩn của dịch chiết từ cây chó đẻ thân xanh (Phyllanthus amarus); nồng độ ức chế tối thiểu (MIC) và nồng độ tiêu diệt tối thiểu (MBC) trên 2 chủng vi khuẩn Vibrio parahaemolitycus (K15) và Vibrio sp. (VT33) ở mật độ 106 CFU/mL gây bệnh hoại tử gan tụy cấp (Acute Hepatopancreatic Necrosis Disease –AHPND) còn được gọi là hội chứng tôm chết sớm (Early Mortality Syndrome - EMS) trên tôm chân trắng (Litopenaeus vannamei) nuôi tại Thừa Thiên Huế, kết quả ban đầu ghi nhận: dịch chiết được chiết xuất dạng cao từ cây chó đẻ thân xanh (P. amarus) có khả năng kháng cả 2 chủng Vibrio parahaemolitycus (K15) và Vibrio sp. (VT33) thử nghiệm từ nồng độ 250 đến 1.000 mg/mL, thể hiện ở đường kính vòng kháng khuẩn dao động từ 16,60–21,40 mm đối với chủng Vibrio parahaemolitycus (K15) và từ 17,60 – 23,60 mm đối với Vibrio sp. (VT33). Kết quả cũng xác định hiệu quả của dịch chiết trên 2 chủng Vibrio parahaemolyticus (K15) và Vibrio sp. (VT123) thể hiện giá trị MIC và MBC tương ứng đạt 125 mg/mL và 500 mg/mL; 62,5 và 500 mg/mL.

scholarly journals pH-based ecological coherence of active canonical methanotrophs in paddy soils

2019 ◽  
Author(s):  
Jun Zhao ◽  
Yuanfeng Cai ◽  
Zhongjun Jia
Keyword(s):  
Soil Ph ◽  
Rice Paddy ◽  
Low Ph ◽  
Paddy Soils ◽  
Type I ◽  
Type Ii ◽  
High Ph ◽  
Niche Specialization ◽  
Significant Difference ◽  
Rice Paddy Soils

Abstract. Soil pH is considered one of the main determinants of the assembly of globally distributed microorganisms that catalyse the biogeochemical cycles of carbon and nitrogen. However, direct evidence for niche specialization of microorganisms in association with soil pH is still lacking. Using methane-oxidizing bacteria (methanotrophs) as a model system of carbon cycling, we show that pH is potentially the key driving force selecting for canonical gamma- (type I) and alpha- (type II) methanotrophs in rice paddy soils. DNA-based stable isotope probing (DNA-SIP) was combined with high-throughput sequencing to identify the taxonomic identities of active methanotrophs in physiochemically contrasting soils from 6 different paddy fields across China. Following microcosm amendment with 13CH4, methane was primarily consumed by Methylocystis-affiliated type II methanotrophs in soils with a relatively low pH (5.44–6.10), whereas Methylobacter/Methylosarcina-affiliated type I methanotrophs dominated methane consumption in soils with a high pH (7.02–8.02). Consumption of 13CH4 contributed 0.203 % to 1.25 % of soil organic carbon, but no significant difference was observed between high-pH and low-pH soils. The fertilization of ammonium nitrate resulted in no significant changes in the compositions of 13C-labelled methanotrophs in the soils, although significant inhibition of methane oxidation activity was consistently observed in low-pH soils. Mantel analysis further validated soil pH, rather than other parameters tested, had significant correlation to the variation of active methanotrophic compositions across different rice paddy soils. These results suggest that soil pH might have played pivotal roles in mediating the niche differentiation of ecologically important aerobic methanotrophs in terrestrial ecosystems and imply the importance of such niche specialization in regulating methane emissions in paddy field under increasingly intensified input of anthropogenic N fertilizers.

scholarly journals Transcriptomic analysis of Pacific white shrimp (Litopenaeus vannamei, Boone 1931) in response to acute hepatopancreatic necrosis disease caused by Vibrio parahaemolyticus

PLoS ONE ◽  
2019 ◽  
Vol 14 (8) ◽  
pp. e0220993 ◽  
Author(s):  
Adrián E. Velázquez-Lizárraga ◽  
José Luis Juárez-Morales ◽  
Ilie S. Racotta ◽  
Humberto Villarreal-Colmenares ◽  
Oswaldo Valdes-Lopez ◽  
...  
Keyword(s):  
Litopenaeus Vannamei ◽  
Vibrio Parahaemolyticus ◽  
Pacific White Shrimp ◽  
Transcriptomic Analysis ◽  
White Shrimp ◽  
Acute Hepatopancreatic Necrosis Disease
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