Last days remaining for this special offer. See link for details.
What do veterinary fish pathologists see down the microscope?
Have you wondered how and what we see when we examine your fish in the laboratory?
Specimens are first preserved in formalin and then sectioned to smaller portions, placed in a machine that will impregnate wax into the tissues, trimmed into wafer thin sections, placed on glass slides, stained with dyes and then cover slipped (see pic below).
This entire process can take between 2-5 days. Only after all that is done can we only begin to examine the fish.
I’ve provided a video of the microscopic examination of a fish in histology section on TheFishVet’s YouTube Channel: http://youtu.be/_4BBlHPT-Ms
So, if you want to get some diagnostic lab testing conducted on your fish colony or farm, no matter where you are in Australia, contact Dr Richmond Loh, The Fish Vet.
See video on preparing fish for lab testing – http://m.youtube.com/watch?v=gZ8HWUEQL5c
The 7th annual C.L. Davis Day Seminar on Diagnostic Pathology – Pathology of aquatic animals, farmed and laboratory fish.
The Indian Association of Veterinary Pathologists (IAVP) with the CL Davis DVM Foundation of USA is offering a one-day seminar on the Pathology of aquatic animals, farmed and laboratory fish including integrated aquaculture and waste management.
The 8-hour seminar will provide information on integrated macroscopic and microscopi pathology of aquatic animals, Piscine models of human disease and fish as laboratory species and important diseases of farmed fish.
The seminar would be presented by Eric Lombardini at the National Research Center on Equines, Hisar (Haryana), India.
Who should attend?
Veterinary pathologists/specialists in aquatic animals working or aspiring to work for industry, academia and government institutions.
The detailed program is available on the following websites:
See also the flyer below:
How do you tube feed a leafy seadragon?
I just gastric tubed a seadragon who hasn’t eaten for a while, with freshly hatched Artemia and I thought I’d to share with sygnathid / seahorse owners on how it is done.
A catheter with the right diameter (thin enough to enter the oesophagus, but wide enough to allow passage of food to be injected) and length (needs to be long enough to reach the oesophagus which is located posterior to the gill chamber) is selected and it is glued to a syringe to prevent it from being dislodged from any back pressure.
The syringe is filled with newly hatched brine shrimp that’s rinsed in freshwater. Why we chose newly hatched Artemia is because it’s packed with nutrients and the particle size is small enough to fit through the bore of the feeding tube. The shrimp is rinsed in freshwater to remove wash off any muck and bacteria.
The feeding tube is inserted into the mouth and gently directed to the back of the throat where you’ll feel a bit if resistance. This is the opening to the stomach. When the fish attempts to swallow, you’ll feel the catheter can be inserted a little further and you’re in!
At this stage, you can slowly inject the food. In my case I gave 2-3ml of a brine shrimp slurry.
Although it is not so critical in other fish species, sygnathids should be kept submerged at all times where possible.
Fingers crossed Mr seadragon comes through.
New Zealand hospital removes ‘asparagus-sized’ eel from man’s bottom !
Read more here:
—
Yours sincerely,
Dr Richmond Loh
BSc BVMS MPhil MANZCVS (Aq & Pathol)
The Fish Vet, Perth, Western Australia.
Veterinary Medicine for fish.
http://www.thefishvet.com.au
Ph: +61 (0)421 822 383
Fish-e Trivia for Monday-itis. Are Mexican walking fish, fish?
Are Mexican walking fish, fish with legs?
My friends when seeing these creatures would either say,”Wow! Cool! These fish have got legs!”
Or they may say,”Ewwwww! The fish have legs!”
Well, the short answer is – no, axolotls are in fact, amphibians just like frogs and toads. They are permanently ‘stuck’ in their larval stage and breathe through their gills and skin! Imagine a tadpole with four legs, a tail and gills. That’s what these axolotls are!
Swimbladder non-inflation overcome by installing surface skimmers.
Swimbladder non-inflation is a big issue with raising larval fish and specifically, in marine fish because of their very small size. This paper illustrates the importance of keeping the water surface clean.
| Aquaculture Research | |||||||||||||||||
| Volume 43, Number 9 (August 2012) | |||||||||||||||||
 |
Promotion of initial swimbladder inflation in Pacific bluefin tuna, Thunnus orientalis(Temminck and Schlegel), larvae | ||||||||||||||||
| Authors: | Michio Kurata, Manabu Seoka, Yoshizumi Nakagawa, Yasunori Ishibashi, Hidemi Kumai, Yoshifumi Sawada | ||||||||||||||||
| Author Affiliations: |
|
||||||||||||||||
| Source: | Aquaculture Research, Volume 43, Number 9 (August 2012) | ||||||||||||||||
| Page Numbers: | 1296 – 1305 | ||||||||||||||||
| Available Full Text: |
|
||||||||||||||||
| Abstract: | Initial swimbladder inflation (ISI) of Pacific bluefin tuna (PBT), Thunnus orientalis,larvae was studied to increase the survival of cultured larvae. Experiment 1 was conducted to explore promotion and inhibition of ISIunder different water surface conditions; including the use of surface skimmer to remove autogenous surface substances (SS), covering the water surface with liquid-paraffin-layer (LP) and oil film (OF), and a control (non-treatment, NT). Significantly higher inflation frequency was observed in SS(62.2%) than NT(11.9%), LP(2.7%) and OF(3.9%). This indicates that ISIin PBTlarvae can be promoted by removal of surface substances on rearing water which inhibit larval air gulping. Experiment 2 aimed to elucidate proper day of larval age to start skimming for promoting ISIwith four different periods of oil film removal: from 3 to 8 (SF3D), 4 to 8 (SF4D), 5 to 8 (SF5D), 6 to 8 (SF6D) days-post-hatch (dph). Significant improvement in ISIfrequency was observed in SF3D (80.2%) but the frequency was very poor in SF4D, SF5D, and SF6D (17.8–7.5%). This implies the need of oil film removal without missing a narrow window, 1 day of 3 dph, to promote ISIin practical PBTlarviculture. | ||||||||||||||||
| Citation: | Michio Kurata, Manabu Seoka, Yoshizumi Nakagawa, Yasunori Ishibashi, Hidemi Kumai, Yoshifumi Sawada . Promotion of initial swimbladder inflation in Pacific bluefin tuna, Thunnus orientalis(Temminck and Schlegel), larvae. Aquaculture Research, Volume 43, Number 9 (August 2012), pp. 1296-1305, <http://ejournals.ebsco.com/direct.asp?ArticleID=4D06AD4FDB656433EF32> | ||||||||||||||||
| URL: | http://ejournals.ebsco.com/direct.asp?ArticleID=4D06AD4FDB656433EF32 | ||||||||||||||||
How do you avoid catching worms from eating sushi?
Anisakiasis can be a real problem when eating raw/uncooked fish such as those served as sashimi. How can you reduce the risk of becoming infected with the worm?
Eating farmed fish rusher than that sourced from the wild will dramatically reduce the risk. Another way is to freeze the fish prior to eating. Freezing of herring in the Netherlands has seen a great decline in human cases of anisakiasis.
Beware of “new tank syndrome” in established ponds!
Have you noticed your fishes are getting hungrier as the weather warms up? Are you increasing your feeding to satisfy their hunger? Beware that your biofilter will lag behind in terms of their ability to convert dissolved fish wastes to nitrate. It’s not unusual to find high levels of ammonia at this time of the year. So keep an eye on it.
Why seek veterinary attention early?
The drug cocktails used to treat sick fish are a common scenario I see, with owners travelling from shop to shop to be recommended one treatment after another.
Some drugs do more harm than good,
some may be directly toxic to fish, some may wreak havoc with your biofilter creating toxic water conditions and some when used incorrectly, can lead to bacterial antibiotic resistance.
Even if the medications themselves do no harm, it eats into valuable time and the disease can spread to others and it can progress beyond recovery.
Previous treatments given may also mask signs of disease and may make it more difficult to diagnose the cause of disease. So it is very important to seek veterinary attention immediately at first signs of disease.