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Aquaculture | 1990

Occurrence of luminous bacterial disease of Penaeus monodon larvae in the Philippines

Celia R. Lavilla-Pitogo; Ma.Cecilia L. Baticados; Erlinda R. Cruz-Lacierda; Leobert D. de la Peña

Larval mortalities associated with luminescence have been observed in epizootic proportions in black tiger prawn (Penaeus monodon) hatcheries in Panay Island, Philippines. Luminescent vibrios, identified as Vibrio harveyi and V. splendidus, were isolated from infected larvae but not from uninfected ones. These bacteria were also recovered readily from seawater samples from nearshore areas, the main source of hatchery rearing water. Thus, it is possible that the nearshore seawater is one major source of infection. Pathogenicity tests resulted in significant mortalities of larvae and postlarvae of P. monodon within 48 h of immersion challenge. Scanning electron microscopic observations show that colonization by the bacteria occurred specifically on the feeding apparatus and oral cavity of the larvae, suggesting an oral route of entry for the initiation of infection.


Aquaculture | 2001

Antibiotic resistance of bacteria from shrimp ponds

Eleonor A. Tendencia; Leobert D. de la Peña

Abstract The incidence of antibiotic resistance was compared in bacteria isolated from pond water, pond sediment, water and sediment from the receiving environment (area where water from pond drains, which is 0 and 50 m away from the exit gate, in this study) and cultured shrimp from ponds that have not used any antimicrobials, ponds that have previously used antimicrobials and ponds that are currently using oxolinic acid. Most of the bacteria isolated from all sample and pond type were Vibrios . Among the Vibrios , V. harveyi were most commonly isolated. Multiple antibiotic resistance (MAR) to at least two antimicrobials was highest in ponds currently using oxolinic acid (24% of bacteria isolated from such ponds), followed by those that have previously used antimicrobials (19%) and the least was those from ponds that have not used any antimicrobials (17%). The lowest incidence of antibiotic resistance was observed in ponds that have not used any antimicrobials (41% of the isolates from such ponds). Among the individual antibiotics, incidence of resistance to oxytetracycline was highest (4.3% of the total number of isolates) followed by furazolidone (1.6%), oxolinic acid (1%) and chloramphenicol (0.66%). Resistance to individual chemotherapeutants did not reflect the pattern of antimicrobial use with ponds that have previously used antimicrobials showing the highest incidence of resistance to one antimicrobial (12% of total isolates from such ponds). Resistance to both oxolinic acid and furazolidone (15% of total number of isolates) was highest compared to other antimicrobial resistance profiles (1–12%). Multiple antimicrobial resistance and intermediate reaction to at least one antimicrobial are associated with antimicrobial use.


Aquaculture | 2001

Genetic diversity of wild and cultured Black Tiger Shrimp (Penaeus monodon) in the Philippines using microsatellites

Zhenkang Xu; Jurgenne H. Primavera; Leobert D. de la Peña; Priscilla Pettit; Jane Belak; Acacia Alcivar-Warren

Abstract Six microsatellites were used to study (1) the genetic diversity of wild Penaeus monodon shrimp from four geographic regions (Palawan, Quezon, Capiz and Negros Occidental-W) in the Philippines, and (2) its association with the status of mangroves and intensity of shrimp culture systems in these regions. Two cultured populations (Negros Occidental-C and Antique) were used for comparison. All six microsatellite loci were polymorphic. A total of 184 different alleles were found over all loci. The total number of alleles per locus ranged from 6 to 54, with allele size ranging from 159 base pairs (bp) to 400 bp. The observed heterozygosity of the six loci ranged from 0.47 to 1.00. The number of genotypes per locus ranged from 5 to 70. F st values showed significant genetic differentiation among the four wild populations. Genetic differences between wild populations were also detected by pairwise comparison based on genotypic and allelic frequencies. Genetic differentiation among wild populations exhibited a positive correlation with mangrove status and intensity of culture systems at P =0.083. The Negros Occidental-W population, which originated from an area with the most severe mangrove loss and the most intensive culture systems, was the most significantly differentiated population. It also showed less genotypes per locus than the other three wild populations, suggesting a decrease in genetic diversity in this population. The population from Capiz, a province with a wide area of extensive culture ponds and few remaining secondary mangroves was the second most differentiated population. The Quezon population, which originated from an area with a few extensive culture ponds and less mangrove destruction, was not genetically different from the Palawan population, which was from a pristine site with mostly primary mangroves and no major aquaculture industry. The cultured populations showed less genetic diversity and were significantly different from the four wild populations based on pairwise F st values and pairwise comparisons of allelic and genotypic frequencies. The results suggest that (a) there was a significant genetic differentiation among the wild P. monodon populations in the Philippines, and (b) the cultured populations were significantly differentiated from the natural populations. More replicate samples from each of the geographic regions are needed to conclusively determine the possibility of an association between genetic differentiation and the status of mangroves and/or intensity of shrimp culture systems.


Diseases of Aquatic Organisms | 2015

Acute hepatopancreatic necrosis disease (AHPND) outbreaks in Penaeus vannamei and P. monodon cultured in the Philippines

Leobert D. de la Peña; Nikko Alvin R. Cabillon; Demy D. Catedral; Edgar C. Amar; Roselyn C. Usero; Wilberto D. Monotilla; Adelaida T. Calpe; Dalisay Dg. Fernandez; Cynthia P. Saloma

Acute hepatopancreatic necrosis disease (AHPND) has recently emerged as a serious disease of cultured shrimp. It has also been described as early mortality syndrome (EMS) due to mass mortalities occurring within 20 to 30 d after stocking of ponds with postlarvae. Here, Penaeus vannamei and Penaeus monodon from shrimp farms in the Philippines were examined for the toxin-producing strain of Vibrio parahaemolyticus due to AHPND-like symptoms occurring in marketable size shrimp. In the P. vannamei, histology revealed typical AHPND pathology, such as sloughing of undifferentiated cells in the hepatopancreatic tubule epithelium. Analysis using the IQ2000 AHPND/EMS Toxin 1 PCR test generated 218 bp and 432 bp amplicons confirmative of the toxin-producing strain of V. parahaemolyticus among shrimp sampled from 8 of 9 ponds. In the P. monodon, histology revealed massive sloughing of undifferentiated cells of the hepatopancreatic tubule epithelium in the absence of basophilic bacterial cells. PCR testing generated the 2 amplicons confirmatory for AHPND among shrimp sampled from 5 of 7 ponds. This study confirms the presence of AHPND in P. vannamei and P. monodon farmed in the Philippines and suggests that the disease can also impact late-stage juvenile shrimp.


Fish Pathology | 2009

Molecular Epidemiology of Koi Herpesvirus

Jun Kurita; Kei Yuasa; Takafumi Ito; Motohiko Sano; Ronald P. Hedrick; M.Y. Engelsma; O.L.M. Haenen; Agus Sunarto; Edy Barkat Kholidin; Hsin-Yiu Chou; Ming-Chen Tung; Leobert D. de la Peña; Gilda D. Lio-Po; Chien Tu; Keith Way; Takaji Iida


Fish Pathology | 2001

Luminescent Vibrios Associated with Mortality in Pond-Cultured Shrimp Penaeus monodon in the Philippines : Species Composition

Leobert D. de la Peña; Celia R. Lavilla-Pitogo; Milagros G. Paner


Jarq-japan Agricultural Research Quarterly | 2004

Mass Mortalities Associated with Viral Nervous Necrosis in Hatchery-Reared Sea Bass Lates calcarifer in the Philippines

Yukio Maeno; Leobert D. de la Peña; Erlinda R. Cruz-Lacierda


Fish Pathology | 2002

Nodavirus infection in hatchery-reared orange-spotted grouper Epinephelus coioides: First record of viral nervous necrosis in the Philippines

Yukio Maeno; Leobert D. de la Peña; Erlinda R. Cruz-Lacierda


Diseases of Aquatic Organisms | 2007

Prevalence of white spot syndrome virus (WSSV) in wild shrimp Penaeus monodon in the Philippines.

Leobert D. de la Peña; Celia R. Lavilla-Pitogo; Corina Belle R. Villar; Milagros G. Paner; Christopher D. Sombito; Geimbo C. Capulos


Fish Pathology | 2003

Mortality in pond-cultured shrimp Penaeus monodon in the Philippines associated with Vibrio harveyi and white spot syndrome virus

Leobert D. de la Peña; Celia R. Lavilla-Pitogo; Atsushi Namikoshi; Toyohiko Nishizawa; Yasuo Inui; Kiyokuni Muroga

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Celia R. Lavilla-Pitogo

Southeast Asian Fisheries Development Center

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Erlinda R. Cruz-Lacierda

Southeast Asian Fisheries Development Center

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Demy D. Catedral

Southeast Asian Fisheries Development Center

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Edgar C. Amar

Southeast Asian Fisheries Development Center

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Gilda D. Lio-Po

Southeast Asian Fisheries Development Center

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Milagros G. Paner

Southeast Asian Fisheries Development Center

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Geimbo C. Capulos

Southeast Asian Fisheries Development Center

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Corina Belle R. Villar

Southeast Asian Fisheries Development Center

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