The Fish Vet's Blog

Ever wondered how your quick decision at the local supermarket impacts others? Do we buy local and support Aussie jobs? Or should we buy “cheap” imports? Are they labelled “cheap” because they’re of lesser quality, or is it just because they can produce it more economically? Does buying imports help support the livelihoods of those who are less fortunate? Does buying imports lead to environmental destruction? Would you support it if it were sustainable? We’re just touching the surface of things…

Aquaculture Economics & Management: Official Journal of the International Association of Aquaculture Economics and Management
Volume 17, Number 1 (March 2013)
	LIVELIHOOD CAPABILITIES AND PATHWAYS OF SHRIMP FARMERS IN THE MEKONG DELTA, VIETNAM
	Authors:	TranThi Phung Ha 1, Han van Dijk 2, Roel Bosma 3, LeXuan Sinh 4
	Author Affiliations:	1: School of Social Sciences and Humanities, CanTho University 2: Rural Development Sociology Group, Wageningen University 3: Aquaculture and Fisheries Group, Wageningen University 4: College of Aquaculture and Fisheries, CanTho University
	Source:	Aquaculture Economics & Management: Official Journal of the International Association of Aquaculture Economics and Management, Volume 17, Number 1 (March 2013)
	Page Numbers:	1 – 30
	Available Full Text:	Full Text: Subscription Required to view full text Format: PDF Size: Unknown Location: Publisher’s Site Authentication: Publisher’s Site
	Abstract:	Shrimp farming is a major livelihood activity in the Mekong Delta in the southernmost part of Vietnam. The Vietnamese government has promoted shrimp farming as a way to reduce poverty, provide employment opportunities and increase exports to support economic development. The shrimp farming system, however, is economically and ecologically risky and may negatively influence the environment and the sustainability of local people’s livelihoods. Because very little is known about the diversity of strategies people employ to deal with these risks, a study was performed in the Mekong Delta across four shrimp farming systems: (1) improved extensive non-forest, (2) mixed mangrove-shrimp, (3) intensive and (4) clustered intensive. The risks and livelihood strategies that were encountered differed systematically across the four farming systems. It was found that the uncertainties that the shrimp farmers faced include limited access rights to the mangrove forest, crop failure due to regular occurrence of shrimp disease, high investment costs and volatile markets for shrimp. Shrimp farmers have created several strategies for coping with these uncertainties, including redesigning farms, producing salt, changing the species farmed from Penaeus monodon to Penaeus vannamei, becoming involved in a cooperative cluster, integrating aquaculture and agriculture, and farming shrimp by organic standards.
	Citation:	TranThi Phung Ha, Han van Dijk, Roel Bosma, LeXuan Sinh . LIVELIHOOD CAPABILITIES AND PATHWAYS OF SHRIMP FARMERS IN THE MEKONG DELTA, VIETNAM. Aquaculture Economics & Management: Official Journal of the International Association of Aquaculture Economics and Management, Volume 17, Number 1 (March 2013), pp. 1-30, <http://ejournals.ebsco.com/direct.asp?ArticleID=44129214A73812D21899&gt;
	URL:	http://ejournals.ebsco.com/direct.asp?ArticleID=44129214A73812D21899

I was contacted by the Australian Southern Bluefin Tuna Industry Association to make an amendment to a previous blog post. I’m happy to receive feedback and correct any misinformation that’s out there.

The passage has been changed from this:

I have heard that the tuna are slaughtered pen-side and all the discards flow back into the same waters where the fish are reared. If this is the case then, diseases such as these would become amplified. Could they perhaps have one slaughter pen where selected individuals are corralled into, this net moved to a different location where the processing boat/barge is sited?

To this: 

If fish were slaughtered pen-side and all the discards flow back into the same waters where the fish are reared, then diseases such as these would become amplified. Fortunately, all byproducts are captured by gutters and bins around harvest tables and are transported to an onshore processing facility for rendering.

See full, edited, blog post at this link –

https://thefishvet.com/2012/02/21/blood-fluke-plagues-the-south-australian-tuna-industry-easy-fix-with-praziquantel/

From: “Dr. David Scarfe”
Date: 21 February 2013 2:46:07 AWST
Subject: AquaVetMed: Putting consuming ISA infected salmon in perspective

February 20, 2013
Industry not selling “sick fish”

Canada – Hysteria created by unprofessional environmentalists will be remembered as an attempted artificial blockade of healthy food for the general population. If the environmental community was truly concerned about the health-related consequences of handling and serving food, they would not bother with some fish that may or may not contain bugs that are harmless to humans, but rather focus its efforts on products that actually represent a health hazard to the cook or the consumer.

You don’t often hear their concerns about common poultry product, despite the US FDA’s statement that “..raw poultry must be handled carefully to prevent cross-contamination. This can occur if raw poultry or its juices come in contact with cooked food or foods that will be eaten raw, such as salad. An example of this is using a cutting board to chop raw chicken and then using the same board to chop tomatoes without washing the board first”.

Most farmed salmon are excellent raw materials for serving as sushi and sashimi- in other words- served raw.
In a recent posting, the East Coast of Canada-based Act for Aquaculture web site explained why farmed salmon from a farm where a few fish were diagnosed to contain the ISA virus were perfectly safe and sensible for human consumption, despite insistence by extreme environmentalists to the contrary.

There has been a lot written and said about salmon farming and ISA – infectious salmon anemia – over the past few weeks. It’s time for all of us to remember some facts and not give in to scare tactics and misinformation. In a world where 870 million people don’t have enough to eat (Source: UN World Food Programme), anti-salmon farming activists are trying to use misinformation to needlessly waste more than one million pounds of quality protein. That’s enough for about six million meals.

Their goal is to shut down Canada’s salmon farming industry, and fear mongering about ISA – with complete disregard for science and fact – is their latest tactic. Recent headlines have been exciting to say the least. No wonder consumers are concerned when media stories leave the impression that sickly, diseased fish are being sent to local grocery stores. The truth is far less lurid.

Here are the facts … … .

See the source (http://tinyurl.com/bkhge67) for the full story.
___________________________
AquaVetMed e-News provides information to veterinary and veterinary-allied subscribers concerning aquatic animal medicine, health, welfare, public health and seafood safety, obtained from a variety of sources (largely AquaVetMed subscribers). While provided by the American Veterinary Medical Association’s, Aquatic Veterinary Medicine Committee and are for public distribution, they do not necessarily reflect the opinion of the AVMA or the veterinary profession. See the AVMA Terms of Use (http://tinyurl.com/29h2rf) for further information.

If e-News information is used elsewhere please acknowledge AquaVetMed as the source. Encourage individuals to subscribe rather than distribute through list serves.

Messages may contain attachments that will have been scanned for known viruses.

Subscription and Contributions: Interested veterinarians and veterinary-allied professionals can subscribe, unsubscribe, or contribute pertinent news or information, by sending a message with “For AquaVetMed -” and the topic in the subject line, to dscarfe@avma.org.

Note: Undelivered e-mails will not be resent; Subscribers will be deleted from the list after repeated undelivered or bounced messages and will have to re-subscribe.

Visit our website: http://www.avma.org

________________________________

SEQ Fish has just completed an RIRDC funded project to assess the viability of a new industry in Australia based on breeding and growing Australian native freshwater turtle for human consumption. The results suggest that Emydura macquarii (signata), the Brisbane River Short Necked turtle, is the most likely candidate for aquaculture systems due to its fecundity, growth rate and hardiness.

Learn more about the project in the newsletter excerpt by clicking on the link below:

Turtle AqCx

The original catchy title was “Drugged Fish Lose Their Inhibitions, Get the Munchies” by Emily Underwood.

After swimming in water laced with a common antianxiety medication, the red-finned fish lose their inhibitions and gobble up prey at a much faster rate, according to a new study presented here today at the annual meeting of the American Association for the Advancement of Science (publisher of ScienceNOW). The animals act strangely even after being exposed to low concentrations of the medication found in rivers worldwide, suggesting that the drug and others like it could affect fish behavior and ecology even in small doses.

Read more at this link.

Shared by Nicole Spooner, AquaVet Classmate.

Shared by Toni Erkinharju via Facebook

RECIPE FOR HOW TO GET REALLY SMART

A customer at Stingray Fishmongers marveled at the owner’s quick wit and intelligence.

‘Tell me, Simon, what makes you so smart?’

‘I wouldn’t share my secret with just anyone, ‘Simon replies, lowering his voice so the other shoppers won’t hear.’ But since you’re a good and faithful customer, I’ll let you in on it. Fish heads. You eat enough of them, you’ll be positively brilliant.’

‘You sell them here?’ the customer asks.

‘Only $4 apiece’, says Simon.

The customer buys three. A week later, he’s back in the store complaining that the fish heads were disgusting and he isn’t any smarter.

‘You didn’t eat enough, ‘says Simon. The customer goes home with 20 more fish heads. Two weeks later, he’s back and this time he’s really angry.

‘Hey, Simon, ‘he complains, ‘you’re selling me fish heads for $4 a piece when I can buy the whole fish for $2. you’re ripping me off!’

‘You see?’ says Simon, ‘you’re smarter already.’

I always thought that this could be a good idea and someone’s actually done the ground work to find evidence that it works!

(I’ve been finding that this has been a recurring theme with all my inventions too!).

I wonder if it can work with other parasites such as flukes, Cryptocaryon and others.

Great work to the primary investigators and the team behind them!

Journal of Fish Diseases
Volume 36, Number 3 (March 2013)
	Filtration of sea louse, Lepeophtheirus salmonis, copepodids by the blue mussel, Mytilus edulis, and the Atlantic sea scallop, Placopecten magellanicus, under different flow, light and copepodid-density regimes
	Authors:	A Bartsch, S M C Robinson, M Liutkus, K P Ang, J Webb, C M Pearce
	Author Affiliations:	no affiliations available
	Source:	Journal of Fish Diseases, Volume 36, Number 3 (March 2013)
	Page Numbers:	361 – 370
	Available Full Text:	Full Text: Subscription Required to view full text Format: PDF Size: unknown Location: Publisher’s Site Authentication: EBSCOhost EJS
	Abstract:	Population management of Lepeophtheirus salmonisin Canada currently relies on chemotherapeutants to remove attached stages of the ectoparasite. However, some populations of L. salmonisare developing resistance to chemotherapeutants making alternate management measures necessary. This article explores the ability of filter-feeding shellfish [i.e. blue mussels (Mytilus edulis) and Atlantic sea scallops (Placopecten magellanicus)] to consume the copepodid stages of L. salmonisin the laboratory under static and flowing water conditions, with variable copepodid densities, and with the aid of a light attractant. Mytilus edulisconsumed copepodids under both static and flowing water conditions, and the proportion of individuals ingested was similar at low and high copepodid densities, suggesting that M. eduliswas not saturated at the concentrations tested. Also, M. edulisconsumed more copepodids when a light attractant was present, suggesting that lights may be useful to concentrate widely dispersed copepodids around cultured shellfish in the field. Finally, P. magellanicusconsumed the same number of copepodids as an equivalent total wet weight of M. edulis. During each of the four separate experiments, shellfish consumed between 18 and 38% of the copepodids presented perhour, suggesting that both species are well suited for low level removal of copepodids over time.
	Citation:	A Bartsch, S M C Robinson, M Liutkus, K P Ang, J Webb, C M Pearce . Filtration of sea louse, Lepeophtheirus salmonis, copepodids by the blue mussel, Mytilus edulis, and the Atlantic sea scallop, Placopecten magellanicus, under different flow, light and copepodid-density regimes. Journal of Fish Diseases, Volume 36, Number 3 (March 2013), pp. 361-370, <http://ejournals.ebsco.com/direct.asp?ArticleID=42ABA5C9A1273865C962&gt;
	URL:	http://ejournals.ebsco.com/direct.asp?ArticleID=42ABA5C9A1273865C962

FYI.

—
Follow me on: Facebook “Fin Page” – YouTube  – Blog – Linkedin – Twitter

—
Yours sincerely,

Dr Richmond Loh
BSc, BVMS, MPhil (Vet Path), MANZCVS (Aquatics), MANZCVS (Pathobiology), DipPM.
Veterinarian | Adjunct Senior Lecturer Murdoch University | WAVMA President-Elect |
Secretary Aquatic Animal Health Chapter – Australian and New Zealand College of Veterinary Scientists (ANZCVS)
The Fish Vet, Perth, Western Australia, AUSTRALIA.

This article was sourced from http://oceanacidification.wordpress.com/2013/02/12/ecological-aspects-of-marine-vibrio-bacteria-exploring-relationships-to-other-organisms-and-a-changing-environment/

Ecological aspects of marine Vibrio bacteria – exploring relationships to other organisms and a changing environment
Posted by Lina Hansson

Heterotrophic bacteria of the genus Vibrio are indigenous in the marine environment although environmental cues regulate their growth and distribution. The attention brought to this genus is due to its many species/strains that are pathogenic to humans and other organisms. Vibrio abundances are strongly coupled to water temperature and salinity but abundance dynamics occur even where these hydrographical parameters are stable. In this thesis, I have studied Vibrio dynamics in relation to other organisms such as phytoplankton (papers I, II and III) and a bivalve host-organism (paper IV) in a changing environment where increasing temperature (paper III) and ocean acidification (paper IV) may influence survival and proliferation of these bacteria. In particular paper I showed that in a tropical coastal area, where the water temperature and salinity were stable across seasons, abundances of Vibrio were tightly coupled to phytoplankton biomass and community composition. A diatom bloom during December seemed to support high numbers of vibrios in waters with otherwise low levels of dissolved organic carbon. Paper II further supports that some phytoplankton can favor Vibrio growth while others seem to have a negative influence on Vibrio abundances. For instance, Skeletonema tropicum, a common diatom in Indian coastal waters, easily eradicated Vibrio parahaemolyticus from sea water in our experiments. In temperate marine areas culturable Vibrio predominantly occurs in the water column during the warmer months. Sediments are suggested to be potential reservoirs when conditions in the water-column are harsh. Accordingly, in paper III we showed that cold-water sediments from geographically separate areas in a boreal region of Scandinavia all contained relative high abundances of total Vibrio spp. and that all sediments also included culturable Vibrio. In agreement with paper I, the fresh input of organic material from phytoplankton blooms, for which chlorophyll a was used as a proxy, seemed to positively influence Vibrio abundances also in the sediments (paper III). Therefore, the pelagic-benthic coupling which can supply the sediments with biomass from the primary production could influence the abundance of Vibrio spp. Increasing temperature had variable influence on sediment-associated Vibrio abundance, with a significant increase in abundances in sediments originating from one area when the temperature reached over 21°C and a generally negative influence of increasing temperature on abundances in sediments originating from another area (paper III). This suggests that the sediments contained different Vibrio communities with varying temperature tolerance traits. Rising levels of carbon dioxide in the atmosphere does not only lead to higher water temperature through the green house effect, but also to acidification of the oceans. Paper IV illustrated how a common bivalve pathogen, Vibrio tubiashii, can be favored in the interaction with a calcifying bivalve host, Mytilus edulis, when this host-pathogen combination was exposed to levels of ocean acidification projected to occur by the end of the 21st century. Thus, global environmental changes may enhance the probability of Vibrio infections in higher organisms.

Asplund M. E., 2013. Ecological aspects of marine Vibrio bacteria – Exploring relationships to other organisms and a changing environment. PhD thesis, University of Gothenburg. Thesis.

There are many drugs and chemicals that enter our waterways that can exert effects on aquatic life even at levels beyond detectable limits by even the most sophisticated of equipment. Immunosuppression, behavioural changes and endocrine disruption are some effects in aquatic animal life that have been reported in the literature due to residues from agrichemicals and human medications. Even algal growth can be affected! There is still a lot of controversy around these findings due to the complexity of the pathogenesis, however, the is evidence out there. There’s no denying this in Sweden, already work is underway to curb such effects by way of advanced techniques for wastewater treatment.

Read more below…

—
Follow me on: Facebook “Fin Page” – YouTube – Blog – Linkedin – Twitter

—
Yours sincerely,

Dr Richmond Loh
BSc, BVMS, MPhil (Vet Path), MANZCVS (Aquatics), MANZCVS (Pathobiology), DipPM.
Veterinarian | Adjunct Senior Lecturer Murdoch University | WAVMA President-Elect |
Secretary Aquatic Animal Health Chapter – Australian and New Zealand College of Veterinary Scientists (ANZCVS)
The Fish Vet, Perth, Western Australia, AUSTRALIA.