Article
Veterinary Sciences
Manuel Lepe-Lopez, Joaquin Escobar-Dodero, Daniel Rubio, Julio Alvarez, Natalia Zimin-Veselkoff, Fernando O. Mardones
Summary: This study utilized the multivariate spatial scan statistic to identify geographic areas and times of sea lice infestation in farmed salmonids in Chile. The results revealed spatial clusters with different infestation levels and associated factors, highlighting the importance of Integrated Pest Management (IPM). Recommendations for an IPM plan were provided, considering factors such as stock density thresholds and chemical control efficacy to prevent resistance and minimize environmental residues.
FRONTIERS IN VETERINARY SCIENCE
(2021)
Article
Veterinary Sciences
Manuel Lepe-Lopez, Joaquin Escobar-Dodero, Natalia Zimin-Veselkoff, Claudio Azat, Fernando O. Mardones
Summary: The study analyzed the habitat suitability for C. rogercresseyi in the marine sites of salmon farms in Chile, using habitat suitability modeling to explore the likelihood of species spatial occurrence based on environmental characteristics. The results indicated that water temperature, water salinity, and current velocity of waters were the most important characteristics limiting C. rogercresseyi distribution in southern Chile.
FRONTIERS IN VETERINARY SCIENCE
(2021)
Article
Fisheries
Jaewoon Jeong, Gregor F. McEwan, Gabriel Arriagada, Cristian Gallardo-Escarate, Crawford W. Revie
Summary: The salmon louse C. rogercresseyi is a common ectoparasite of farmed salmonids in Chile, and further research is required to adequately model its complete population dynamics and support effective control and mitigation on Chilean salmon farms.
JOURNAL OF FISH DISEASES
(2022)
Article
Multidisciplinary Sciences
Cristian Gallardo-Escarate, Valentina Valenzuela-Munoz, Gustavo Nunez-Acuna, Diego Valenzuela-Miranda, Ana Teresa Goncalves, Hugo Escobar-Sepulveda, Ivan Liachko, Bradley Nelson, Steven Roberts, Wesley Warren
Summary: This study reports a chromosome-scale assembly of the sea louse genome, identifying coding RNAs and non-coding RNAs, particularly long non-coding RNAs and microRNAs, through whole transcriptome sequencing. The genomic resource for C. rogercresseyi serves as a valuable tool for developing sustainable control strategies in the salmon aquaculture industry.
Article
Fisheries
Hernan A. Canon Jones, Trinidad Schlotterbeck Suarez, Mario Castillo-Ruiz, Hernan Cortes Gonzalez, Gladys Asencio, Susana Latuz, Ricardo San Martin
Summary: The study evaluated the effect of two commercial products of Quillaja saponaria saponin extract on the mortality of sea-lice Caligus rogercresseyi. The results showed that higher saponin content in the product led to higher mortality rates, even persisting after the extracts were removed. This suggests that saponins from Q. saponaria extracts could be used for controlling or preventing infestation of C. rogercresseyi in salmonids in Chile.
JOURNAL OF THE WORLD AQUACULTURE SOCIETY
(2021)
Article
Fisheries
Maria Teresa Gonzalez, Natalia Veronica Leiva, Fabiola Sepulveda, Gladys Asencio, Juan Antonio Baeza
Summary: Using the cox1 gene, this study evaluated the genetic variation of C. rogercresseyi in farmed Atlantic salmon in southern Chile, finding significant morphometric differences among sites but no genetic structure among farms. This suggests that C. rogercresseyi is panmictic along an extensive latitudinal range in southern Chile. Further research using more powerful markers is needed to confirm the genetic homogeneity of this parasite.
JOURNAL OF FISH DISEASES
(2021)
Article
Fisheries
Emma Zalcman, Amy Burroughs, Anne Meyer, Alison Hillman, Rohan Sadler, Ben Madin, Catriona Mackenzie, Michael P. Ward, Mark Stevenson, Jonathan Happold, Jennifer Hutchison, Alicia L. Gallardo Lagno, Angus Cameron, Brendan Cowled
Summary: Sea lice infestation poses significant challenges to the salmonid farming industry in Chile, with potential negative effects on welfare, productivity, and disease susceptibility. The implementation of a national surveillance program has shown some success in reducing sea lice abundance, but further investigations are needed to explore additional risk factors and potential improvements in lice control.
Article
Fisheries
Maria F. Morales-Rivera, Diego Valenzuela-Miranda, Valentina Valenzuela-Munoz, Gustavo Nunez-Acuna, Ruben Avendano-Herrera, Cristian Gallardo-Escarate
Summary: This study aimed to characterize the bacterial community associated with Caligus rogercresseyi in Chilean salmon aquaculture. It found that sea lice can act as potential reservoirs for fish diseases in the aquatic environment.
Article
Fisheries
Diego Valenzuela-Miranda, Valentina Valenzuela-Munoz, Barbara P. Benavente, Marcelo Munoz-Trorcoso, Gustavo Nunez-Acuna, Cristian Gallardo-Escarate
Summary: Parasitism by sea lice affects the diversity of microbial communities in Atlantic salmon, leading to the occurrence of opportunistic bacterial pathogens and perturbation of the correlation between skin and gut microbiota. Sea lice can act as vectors for transmitting specific bacterial species and induce tissue-specific functional dysbiosis.
Article
Fisheries
Tamara S. Vera, Moises Sandoval, Juan P. Cumillaf, Freddy Delgado-Lagos, Luis Arias-Darraz, Juan G. Carcamo
Summary: This study evaluated differential protein expression between males and females of Caligus rogercresseyi in sea and estuaries of the Chilean coast. Using the TMT-based proteomic approach, 1666 proteins were detected, with 688 proteins showing differential expression between the sexes. Additionally, 148 proteins were exclusively expressed in males and 211 proteins in females. The sex-biased protein expression identified in this study is consistent with the observed differences in anti-parasitic sensitivities between male and female C. rogercresseyi.
Article
Biotechnology & Applied Microbiology
Gustavo Nunez-Acuna, Valentina Valenzuela-Munoz, Diego Valenzuela-Miranda, Cristian Gallardo-Escarate
Summary: Recent studies have shown the role of miRNAs in gene regulation related to drug metabolism and detoxification in terrestrial species. However, research on marine ectoparasites, especially in investigating molecular mechanisms of pesticide resistance, is limited. This study explored the miRNome responses of the sea louse Caligus rogercresseyi to delousing drugs and identified potential gene regulation mechanisms involving miRNAs and long non-coding RNAs, shedding light on novel pharmacological mechanisms associated with drug resistance in sea lice species.
MARINE BIOTECHNOLOGY
(2021)
Article
Fisheries
Margarita P. Gonzalez-Gomez, Claudia Spinetto, Cristian Oyarzo, Danny Alvarez, Renato Oyarzun, Mario Rivas
Summary: This study aimed to determine the effects of temperature and light on the sensitivity of the parasite Caligus rogercresseyi to the insecticide azamethiphos. The results showed that temperature and light did not significantly affect the sensitivity profile of the parasite, except for a higher effective concentration at 9 degrees C. These findings are important for the treatment and sustainability of the salmon industry.
Article
Fisheries
Constanza Saez-Vera, Gustavo Nunez-Acuna, Cristian Gallardo-Escarate
Summary: This study assessed the sensitivity of sea lice to delousing drug azamethiphos using the time-to-response method coupled with gene biomarkers. Results showed lower ET50 indexes in susceptible sea lice populations and identified three potential biomarker genes related to drug sensitivity. The study offers novel insights for evaluating delousing drug sensitivity in Chilean salmonid farms through ET50-PCR bioassay.
Article
Fisheries
Valentina Valenzuela-Munoz, Barbara P. Benavente, Antonio Casuso, Yeny Leal, Diego Valenzuela-Miranda, Gustavo Nunez-Acuna, Constanza Saez-Vera, Cristian Gallardo-Escarate
Summary: This study demonstrates that immunizing Atlantic salmon with IPath(R) can significantly modulate the transcriptome of sea lice and induce abnormal reproductive development and inflammatory responses. Furthermore, downregulation of multiple immune-related and iron homeostasis-related genes was observed in the head kidney and skin tissues of immunized fish.
FISH & SHELLFISH IMMUNOLOGY
(2021)
Article
Multidisciplinary Sciences
Diego Valenzuela-Miranda, Ana Teresa Goncalves, Valentina Valenzuela-Munoz, Gustavo Nunez-Acuna, Ivan Liachko, Bradley Nelson, Cristian Gallardo-Escarate
Summary: The sea louse Caligus rogercresseyi has become a major obstacle to the sustainable development of salmon aquaculture in Chile. Recent genome sequencing revealed a large bacterial community associated with the sea louse, raising concerns about potential new sanitary threats. By using chromosome proximity ligation (Hi-C) and long-read sequencing, the researchers successfully reconstructed the genomic profiles of the C. rogercresseyi microbiota. This study identified several pathogenic bacteria, virulence factors, and antibiotic resistance genes, while also suggesting a mutualistic relationship between C. rogercresseyi and its associated microbiota.
SCIENTIFIC REPORTS
(2022)