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So far we haven’t been able to do it…

Have a read of this article.

Culture herbivores.

Aquaculture
Volume 353, Number 11 (June 2012)
	Effects of plant-based diets on the distal gut microbiome of rainbow trout (Oncorhynchus mykiss)
	Authors:	Atul R. Desai, Matthew G. Links, Stephanie A. Collins, Graeme S. Mansfield, Murray D. Drew, Andrew G. Van Kessel, Janet E. Hill
	Author Affiliations:	no affiliations available
	Source:	Aquaculture, Volume 353, Number 11 (June 2012)
	Page Numbers:	134 – 142
	Available Full Text:	Full Text: Subscription Required to view full text Format: PDF Size: Unknown Location: Publisher’s Site Authentication: Publisher’s Site
	Abstract:	Replacement of fish meal in aquaculture diets with plant proteins is economically desirable, but the effects of alternative protein sources on the intestinal microbiota and fish health are poorly understood. We examined the intestinal microbiome of 108 rainbow trout (Oncorhynchus mykiss) fed with diets including plant ingredients (peas, soybean, canola) at two processing levels (meal, concentrate), or a fish meal (FM) control diet. Microbial community profiles were determined using pyrosequencing of cpn60 PCR products and 16S rRNA DGGE. Microbial profiles of fish fed the FM diet changed over the course of the study with reduction in species richness and diversity and therefore evaluation of the effects of experimental diets was accomplished through comparison of each diet with its concurrent FM control. Plant ingredient diets were associated with higher Firmicutes:Proteobacteria ratios than controls. Both DGGE and pyrosequencing data showed that microbiomes of fish fed meal-based diets were more distinguishable from the FM control microbiomes than were the microbiomes of fish fed protein concentrate diets. Changes in the FM diet associated profiles could be the result of age-related physiological changes in these fish or a long-term effect of the change in environment from outdoor aquaculture facility to an indoor re-circulating facility. Regardless of the reason, these observations have significant implications for future evaluations of diets and ingredients. We also demonstrated changes in the intestinal microbiome that may contribute to negative health outcomes when diets contain plant meal proteins. These changes in microbiome structure can be minimized with additional processing of plant ingredients.
	Citation:	Atul R. Desai, Matthew G. Links, Stephanie A. Collins, Graeme S. Mansfield, Murray D. Drew, Andrew G. Van Kessel, Janet E. Hill . Effects of plant-based diets on the distal gut microbiome of rainbow trout (Oncorhynchus mykiss). Aquaculture, Volume 353, Number 11 (June 2012), pp. 134-142, ;
	URL:	http://ejournals.ebsco.com/direct.asp?ArticleID=442BB43891C01A39E269

http://www.thefishvet.com.au

Did you know that no matter where you are in the world, you can obtain university level training on fish health by internationally recognised institutes?

Have you considered Online courses?

Several courses that have come to my attention include:

Piscivorous birds love them too!

Journal of the World Aquaculture Society
Volume 43, Number 4 (August 2012)
	Economic Impact of Double-Crested Cormorant, Phalacrocorax auritus, Depredation on Channel Catfish, Ictalurus punctatus,Aquaculture in Mississippi, USA
	Authors:	Brian S. Dorr 1, Loren W. Burger 2, Scott C. Barras 3, Kristina Casscles Godwin 4
	Author Affiliations:	1: U.S. Department of Agriculture, Wildlife Services, National Wildlife Research Center, Mississippi Field Station, P.O. Box 6099, Mississippi State, Mississippi 39762, USA 2: Department of Wildlife, Fisheries and Aquaculture, P.O. Box 9690, Mississippi State, Mississippi 39762-9690, USA 3: U.S. Department of Agriculture, Wildlife Services, P.O. Box 130, Moseley, Virginia 23120, USA 4: U.S. Department of Agriculture, Wildlife Services, P.O. Drawer FW, 200 Thompson Hall, Mississippi State, Mississippi 39762, USA
	Source:	Journal of the World Aquaculture Society, Volume 43, Number 4 (August 2012)
	Page Numbers:	502 – 513
	Available Full Text:	Full Text: Subscription Required to view full text Format: PDF Size: unknown Location: Publisher’s Site Authentication: EBSCOhost EJS
	Abstract:	The Yazoo River Basin of Mississippi, USA, supports the largest concentration of hectares devoted to channel catfish, Ictalurus punctatus, aquaculture production in North America. The Yazoo Basin also supports large numbers of resident, wintering and migrating fish-eating birds, with the Double-crested Cormorant, Phalacrocorax auritus, implicated as the most serious depredating species. We used data from aerial surveys of numbers and distribution of cormorants in the Yazoo Basin and on commercial catfish ponds during winters (November–April) 2000–2001 and 2003–2004 to refine estimates of regional economic losses due to cormorant depredation. In both periods, the greatest monthly estimates of cormorant foraging occurred from 1 January to 31 March. Losses in terms of biomass, number, and dollar value were greater for foodfish ponds than fingerling ponds. Monthly weighted estimates of catfish consumed were 1775.3 and 1346.6 m.t. over winters 2000–2001 and 2003–2004, respectively. Total estimated losses for foodfish and fingerling ponds in 2000–2001 were $11.56 and $0.48 million, respectively, and in 2003–2004 were $5.22 and $0.40 million, respectively. Maximum dollar loss occurred during March in 2000–2001 and during February in 2003–2004. In this study, the volatility in variable production costs and nominal sales price, and distribution of cormorants on pond types and regionally were key factors in resulting economic loss estimates.
	Citation:	Brian S. Dorr, Loren W. Burger, Scott C. Barras, Kristina Casscles Godwin . Economic Impact of Double-Crested Cormorant, Phalacrocorax auritus, Depredation on Channel Catfish, Ictalurus punctatus,Aquaculture in Mississippi, USA. Journal of the World Aquaculture Society, Volume 43, Number 4 (August 2012), pp. 502-513, <http://ejournals.ebsco.com/direct.asp?ArticleID=4EC698D4B4A0D0A9C0D8&gt;
	URL:	http://ejournals.ebsco.com/direct.asp?ArticleID=4EC698D4B4A0D0A9C0D8

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Aquaculture
Volume 357, Number 3 (August 2012)
	Cytokine responses in the common carp, Cyprinus carpioL. treated with baker’s yeast extract
	Authors:	G. Biswas, H. Korenaga, H. Takayama, T. Kono, H. Shimokawa, M. Sakai
	Author Affiliations:	no affiliations available
	Source:	Aquaculture, Volume 357, Number 3 (August 2012)
	Page Numbers:	169 – 175
	Available Full Text:	Full Text: Subscription Required to view full text Format: PDF Size: Unknown Location: Publisher’s Site Authentication: Publisher’s Site
	Abstract:	Cytokines are important regulators of the immune system and investigation of their functions may prove useful for the development of vaccines and immunostimulants for aquaculture. We therefore investigated the cytokine [interleukin (IL)-1ß, IL-10, IL-12 p35 and p40, tumor necrosis factor (TNF)-a, CXC-chemokine and interferon (IFN)-a and ?] responses of the common carp, Cyprinus carpioL., upon treatment with a commercial baker’s yeast extract (CW-I) that contained nucleotides and ß-glucan. Additionally, to confirm that the CW-I-induced cytokines were functional, we also assessed the effect of CW-I administration on superoxide anion production and phagocytic activities of head kidney leucocytes and resistance to Aeromonas hydrophilainfection in the common carp. Our results demonstrate that baker’s yeast extract-treated fish displayed a significant up-regulation of pro-inflammatory cytokine (IL-1ß, IL-12 p35 and p40, TNF-a, CXC-chemokine, IFN-?2) gene expression and a down-regulation of anti-inflammatory cytokine (IL-10) gene expression. Furthermore, significantly increased phagocytic activity and superoxide anion production in kidney cells, and resistance to a bacterial pathogen, were observed in the yeast extract-treated fish compared to non-treated fish. The current study indicates the immunostimulatory effects of a baker’s yeast extract rich in nucleotides and ß-glucan on the carp immune system and supports its potential use in aquaculture.
	Citation:	G. Biswas, H. Korenaga, H. Takayama, T. Kono, H. Shimokawa, M. Sakai . Cytokine responses in the common carp, Cyprinus carpioL. treated with baker’s yeast extract. Aquaculture, Volume 357, Number 3 (August 2012), pp. 169-175, ;
	URL:	http://ejournals.ebsco.com/direct.asp?ArticleID=4452BF835526CF3E9375

http://www.thefishvet.com.au

Following on from my post last week about the planned Koi Herpesvirus (KHV) release (https://thefishvet.wordpress.com/2012/07/26/exotic-carp-killer-virus-planned-to-be-released-in-as-little-as-5-years/), the lead scientist on the animal experimentation stated that the disease course would be variable and is temperature dependent. It will take one week for the fish to die at a water temperature of 26^oC and up to 3 weeks to kill at 17^oC.

This being said, there is an animal welfare aspect that has not been addressed. Practices that were acceptable in the 1950’s in terms of inflicting pain and suffering on “pests” should not be tolerated today.

The ends do not justify the means.

This is an interesting concept, but it wouldn’t work in Australia because we have introduced killer rabbit diseases (myxomatosis
and calicivirus) as a measure to control feral rabbits. This has also been the one of the factors in the demise of the rabbit industry in Australia. It’s a lesson we need to remember whenever a biological control agent is ever to be considered for any purpose. It is whether we plan to ever use the species for any other purposes (pets, meat, leather/fur).

A good case in point is the common carp. The exotic killer koi herpesvirus could be released into the wild in Australia in as little as 5 years if some scientists and fisherfolk lobbyists could have their own way. Could Australia find a use for this fish? Live export to improve genetic stocks in their native Europe? Sustainable food fish aquaculture for local consumption or export? Fertiliser? Coarse fishing?

Australia could remain the only place in the world with a carp population that is free from so many of the killer diseases. In terms of food security, should we be protecting the humble carp rather than release the killer virus amongst them?

http://www.thefishvet.com.au

Journal of Applied Aquaculture
Volume 24, Number 2 (April 2012)
	Rearing Rabbits Over Earthen Fish Ponds in Rwanda: Effects on Water and Sediment Quality, Growth, and Production of Nile Tilapia Oreochromis niloticus
	Authors:	Simon Rukera Tabaro 1, Onisimo Mutanga 1, Denis Rugege 1, Jean-Claude Micha 2
	Author Affiliations:	1: University of KwaZulu-Natal, Faculty of Sciences and Agriculture, School of Environmental Sciences, Geography, Centre for Environment, Agriculture & Development 2: University of Namur, Department of Biology, Research Unit in Environmental Biology
	Source:	Journal of Applied Aquaculture, Volume 24, Number 2 (April 2012)
	Page Numbers:	170 – 181
	Available Full Text:	Full Text: Subscription Required to view full text Format: PDF Size: unknown Location: Publisher’s Site Authentication: EBSCOhost EJS
	Abstract:	Nine earthen ponds of 400 m2each, were stocked with 800 mixed sex Nile tilapia Oreochromis niloticusfingerlings (14 g mean weight stocked at 2 fish/m-2) and fertilized with rabbit droppings from rabbits reared over fish ponds and stocked at three different densities: T1 = one, T2 = two, and T4 = four rabbits per 100 m2of pond. After 152 days, results from this integrated rabbit/fish system showed: 1) increasing nutrient content of all ponds in the three treatments except for nitrates, which decreased with time and, 2) good water quality in terms of pH, dissolved oxygen, and turbidity. Fish mean weight at harvest and fish yield were higher in ponds fertilized by the highest rabbit stocking rate: 42.32 g and 6.35 ± 1.0 kg/are, respectively (1 are = 100 m2).
	Citation:	Simon Rukera Tabaro, Onisimo Mutanga, Denis Rugege, Jean-Claude Micha . Rearing Rabbits Over Earthen Fish Ponds in Rwanda: Effects on Water and Sediment Quality, Growth, and Production of Nile Tilapia Oreochromis niloticus. Journal of Applied Aquaculture, Volume 24, Number 2 (April 2012), pp. 170-181, ;
	URL:	http://ejournals.ebsco.com/direct.asp?ArticleID=48CF8D9813011C307401

http://www.thefishvet.com.au

Dear Fishy folks,

I hope you have all been enjoying reading my posts so far and despite my “corny” Monday-itis “dad” jokes. Now I’d like to include a new recurring subject and I will need your help with populating it.

The theme for the new subject is “fish trivia”. Anything that’s interesting about fishes, starting with the popular aquarium fishes. It could be where they come from, how they live, how they catch their prey, why they have particular patterning, etc.

An example to illustrate what I’m after is this :

Did you know that when it comes to swordtail swords, size DOES matter? Female swordtail fish shows preference to the male with the longest tail.

You can email your Fish Trivia to:
thefishvet@gmail.com

Thank you in advance for contributing and for your continued following.

Following on from a previous post (https://thefishvet.wordpress.com/2012/07/27/imminent-closure-of-the-aquatic-lab-in-townsville-what-are-the-ramifications/), there is an update about the impending veterinary laboratory closure.

THE State Government has shelved plans for an $18 million biosecurity lab in Townsville, which was to replace the old lab in the suburb of Oonoonba, which is closing. The Opposition and the Australian Party have criticised the move and said that it left North and Far North Queensland exposed to biosecurity risks. It could also mean the loss of up to 20 jobs, which follows recent media reports that there would be 550 jobs cut in the Agriculture department. Opposition agriculture spokesman Tim Mulherin said construction had already begun at the facility. Minister for Agriculture John McVeigh said the facility was unfunded, and he made the decision based on the need to rein-in spending. He said that testing for major outbreaks was done at Coopers Plains, Brisbane, while animal health tests were done in Geelong, and that the government was committed to biosecurity .

The decision has shocked aquaculture industries in Far North Queensland, which say it has serious and significant ramifications for the detection of both aquatic and terrestrial animal diseases. The Oonoonba facility has done very important work on the detection of diseases in marine species farmed in the tropics, including prawns and barramundi. While QFF fully supports the need for the State Budget to be restored to order, the impact of the closure of this lab will need to be managed to ensure critical services can be delivered effectively and economically for producers. These matters as yet have not been discussed with industry groups. There seems little doubt that the service is important but there remains widespread concern about whether the other options for the provision of that service have the capacity to handle the increased workload or that testing can be done in a timely and cost-effective way.

The Minister for Agriculture, Forestry & Fisheries, John Mc Veigh.

Following on from my post last week about the planned Koi Herpesvirus (KHV) release (https://thefishvet.wordpress.com/2012/07/26/exotic-carp-killer-virus-planned-to-be-released-in-as-little-as-5-years/),

has anyone given a thought about whether this will be any more effective than goldfish herpesvirus that “accidentally” introduced into Australia some 10 years ago? Today, it is clear that it has had no effect on feral goldfish.

Dr Rodman Getchell from Cornell University presented the findings of the 2005 KHV incident at Chautauqua Lake, at this year’s Aquavet II workshop. Imagine your once pristine lake, becoming littered by tonnes of smelly, decaying fish. There was an initial high level of kill and there was a massive clean-up effort undertaken by the local association and by the New York State Dept of Environment and Conservation. Many fish were trucked to a huge trench that had been dug at the local landfill. There was no way of containing the virus and it subsequently spread to other water bodies and to residents’ home ponds, killing these fish as it swept across the state. Today, the wild carp population has rebounded.