All about Fish Vetting – Dr Richmond Loh
My dad was surfing the net today and found a YouTube video of a DIY Aquaponics setup. He read to my mother about how this guy described his setup and every now and then, remarked that it’s just so similar to his son’s setup.
Lo and behold, the person signed off as Dr Richmond Loh, The Fish Vet!
So funny what my 76yo father finds on the net!
Q: If seaweed had breasts, what would they wear?
A: Algae-bra.
Though not an animal welfare type paper, this research details what parameters are used to quantitatively identify stress in the fish.
In cases of stress, the following parameters would be depressed and they include liver and muscle glycogen, ascorbic acid levels in organs, acetylcholine esterase (AchE) and metabolic enzymes (e.g. alkaline phosphatase (ALP) and adenosine triphosphosphtase (ATPase) activities in liver and muscle tissues).
| Aquaculture International: Journal of the European Aquaculture Society | |||||||||||||||||
| Volume 21, Number 1 (February 2013) | |||||||||||||||||
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Response of a freshwater air-breathing fish, Clarias batrachusto salinity stress: an experimental case for their farming in brackishwater areas in Andaman, India | ||||||||||||||||
| Authors: | Kamal Sarma 1, K. Prabakaran 1, P. Krishnan 1, G. Grinson 1, A. Anand Kumar 1 | ||||||||||||||||
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| Source: | Aquaculture International: Journal of the European Aquaculture Society, Volume 21, Number 1 (February 2013) | ||||||||||||||||
| Page Numbers: | 183 – 196 | ||||||||||||||||
| Available Full Text: |
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| Abstract: | The study was conducted to assess the effects of salinity on growth and biochemical composition of freshwater catfish, Clarias batrachus. A static nonrenewable acute toxicity bioassay test was conducted and LC50of salinity for 96-h exposure to the fingerling (14.5 cm) was 12.52 ‰. Based on these results, two sublethal salinity levels, viz. 4 and 8 ‰ were selected to study the long-term effects of salinity on C. batrachusfor a period of 90 days. From the study, it was found that growth and survival rate were less in saline water (4 and 8 ‰). Maximum growth and survival were recorded in freshwater (0 ‰ salinity) and subsequently at 4 and 8 ‰. To assess the biochemical alteration, few important biomarkers were estimated. At the end of 90 days rearing period, glucose level in the brain and blood of C. batrachuswas found to decrease with salinity. The level of liver and muscle glycogen in the fish reared at 4 ‰ was lower than that of control. Ascorbic acid in all organs under study was found to decrease with increasing salinity, which was attributed to stress mitigation effect of vitamin C. Acetylcholine esterase (AchE) activity recorded a gradual decrease with increasing salinity. Metabolic enzymes, alkaline phosphatase (ALP) activity and adenosine triphosphosphtase (ATPase) activity also reduced both in liver and muscle tissues with increasing salinity. From the present investigation, it can be concluded that exposure to higher salinity significantly (P< 0.01) affects the growth and physiological response of Clarias batrachus.The study was conducted to assess the effects of salinity on growth and biochemical composition of freshwater catfish, Clarias batrachus. A static nonrenewable acute toxicity bioassay test was conducted and LC50of salinity for 96-h exposure to the fingerling (14.5 cm) was 12.52 ‰. Based on these results, two sublethal salinity levels, viz. 4 and 8 ‰ were selected to study the long-term effects of salinity on C. batrachusfor a period of 90 days. From the study, it was found that growth and survival rate were less in saline water (4 and 8 ‰). Maximum growth and survival were recorded in freshwater (0 ‰ salinity) and subsequently at 4 and 8 ‰. To assess the biochemical alteration, few important biomarkers were estimated. At the end of 90 days rearing period, glucose level in the brain and blood of C. batrachuswas found to decrease with salinity. The level of liver and muscle glycogen in the fish reared at 4 ‰ was lower than that of control. Ascorbic acid in all organs under study was found to decrease with increasing salinity, which was attributed to stress mitigation effect of vitamin C. Acetylcholine esterase (AchE) activity recorded a gradual decrease with increasing salinity. Metabolic enzymes, alkaline phosphatase (ALP) activity and adenosine triphosphosphtase (ATPase) activity also reduced both in liver and muscle tissues with increasing salinity. From the present investigation, it can be concluded that exposure to higher salinity significantly (P< 0.01) affects the growth and physiological response of Clarias batrachus. | ||||||||||||||||
| Citation: | Kamal Sarma, K. Prabakaran, P. Krishnan, G. Grinson, A. Anand Kumar . Response of a freshwater air-breathing fish, Clarias batrachusto salinity stress: an experimental case for their farming in brackishwater areas in Andaman, India. Aquaculture International: Journal of the European Aquaculture Society, Volume 21, Number 1 (February 2013), pp. 183-196, <http://ejournals.ebsco.com/direct.asp?ArticleID=459A98EB734F97A3C403> | ||||||||||||||||
| URL: | http://ejournals.ebsco.com/direct.asp?ArticleID=459A98EB734F97A3C403 | ||||||||||||||||
Tank wall collision is one of the major causes of mortality during the early-stage rearing of Pacific bluefin tuna. This paper details changing the water flow rate as a preventive measure.
I wonder if an air-bag would work… But seriously, have a ring of air around the tank sides.
| Aquaculture International: Journal of the European Aquaculture Society | |||||||||||||||||
| Volume 21, Number 1 (February 2013) | |||||||||||||||||
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Critical swimming speed and maximum sustainable swimming speed of juvenile Pacific bluefin tuna, Thunnus orientalis | ||||||||||||||||
| Authors: | F. S. Sabate 1, Y. Nakagawa 1, T. Nasu 1, W. Sakamoto 1, S. Miyashita 1 | ||||||||||||||||
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| Source: | Aquaculture International: Journal of the European Aquaculture Society, Volume 21, Number 1 (February 2013) | ||||||||||||||||
| Page Numbers: | 177 – 181 | ||||||||||||||||
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| Abstract: | Tank wall collision is one of the major causes of mortality during the early-stage rearing of Pacific bluefin tuna, Thunnus orientalis(PBT). Therefore, to design a rearing environment that meets the needs of juvenile PBT, it is important to gather information about their swimming capabilities. We conducted experiments to examine the relative critical swimming speed (RCSS) and maximum sustainable swimming speed (MSSS) of early-stage PBT. The fish were kept in 3-tonne tanks and fed on artificial pellets every 2 h from dusk to dawn. We conducted two sets of experiments to measure swimming speed; the fish were introduced one at a time into a water funnel, and the water current velocity was gradually increased over time to estimate RCSS, or the water current was kept at a constant velocity to estimate MSSS. We measured the RCSS of 72 PBT juveniles (24–29 days after hatching (DAH); standard length (SL), 15.0 ± 2.3 mm) and the MSSS of 32 PBT juveniles (28–37 DAH; SL, 20.0 ± 5.1 mm) in the laboratory. The RCSS ranged from 4.7 to 20.3 SL/s (average, 12.4 ± 3.3 SL/s), and the MSSS was estimated to be approximately 4 SL/s. We speculate that introducing a water current in the rearing tank of no more than 4 SL/s could positively affect the survival of juvenile PBT.Tank wall collision is one of the major causes of mortality during the early-stage rearing of Pacific bluefin tuna, Thunnus orientalis(PBT). Therefore, to design a rearing environment that meets the needs of juvenile PBT, it is important to gather information about their swimming capabilities. We conducted experiments to examine the relative critical swimming speed (RCSS) and maximum sustainable swimming speed (MSSS) of early-stage PBT. The fish were kept in 3-tonne tanks and fed on artificial pellets every 2 h from dusk to dawn. We conducted two sets of experiments to measure swimming speed; the fish were introduced one at a time into a water funnel, and the water current velocity was gradually increased over time to estimate RCSS, or the water current was kept at a constant velocity to estimate MSSS. We measured the RCSS of 72 PBT juveniles (24–29 days after hatching (DAH); standard length (SL), 15.0 ± 2.3 mm) and the MSSS of 32 PBT juveniles (28–37 DAH; SL, 20.0 ± 5.1 mm) in the laboratory. The RCSS ranged from 4.7 to 20.3 SL/s (average, 12.4 ± 3.3 SL/s), and the MSSS was estimated to be approximately 4 SL/s. We speculate that introducing a water current in the rearing tank of no more than 4 SL/s could positively affect the survival of juvenile PBT. | ||||||||||||||||
| Citation: | F. S. Sabate, Y. Nakagawa, T. Nasu, W. Sakamoto, S. Miyashita . Critical swimming speed and maximum sustainable swimming speed of juvenile Pacific bluefin tuna, Thunnus orientalis. Aquaculture International: Journal of the European Aquaculture Society, Volume 21, Number 1 (February 2013), pp. 177-181, <http://ejournals.ebsco.com/direct.asp?ArticleID=45D686120F3F3CD3180A> | ||||||||||||||||
| URL: | http://ejournals.ebsco.com/direct.asp?ArticleID=45D686120F3F3CD3180A | ||||||||||||||||
It’s not been an easy road to acquire specialised knowledge, skills and training as described by a colleague, even in the US. So, they have compiled a list of training providers and their courses on their blog.
Check it out here:
http://avsnca.com/aquatic-veterinary-medicine-resources/comment-page-1/
There will also be a couple of courses being run in Australia this year; in July (https://thefishvet.com/2013/01/11/2013-frdc-australasian-scientific-conference-on-aquatic-animal-health/)
and another in August (https://thefishvet.com/2012/12/28/the-24th-international-conference-of-the-world-association-for-the-advancement-of-veterinary-parasitology-will-be-in-perth-australia/).
Also, join WAVMA to network with other fish vets.
Why culture for bacteria? The answer can be found in a previous post (
https://thefishvet.com/2012/10/13/whats-the-best-antibiotic-to-treat-sick-fish-with/).
But do you ever have trouble trying to take an aseptic sample from the kidney of a tiny fish and find that the giant cotton wool swab ends up swabbing everything, but the kidney?
Ensuring that you take a targeted sample will ensure that whatever the bacteriology laboratory isolates, itis likely to be significant, rather than mere environmental contaminant.
Also, my fish bacteriologist colleague says that aquatic bacteria survive better in Amies transport media that contains charcoal.
This swab pictured is the ideal design for fish vetting and it’s what I carry in my kit at all times.
These bacterial transport swabs with small tips are perfect for aseptically sampling from small fish organs. The charcoal media guarantees longevity of the bugs so they can reach the lab alive.
Enquire with TheFishVet regarding supply of these Transwabs for your veterinary clinic or laboratory.
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Yours sincerely,
Dr Richmond Loh
BSc BVMS MPhil MANZCVS (Aq & Pathol)
The Fish Vet, Perth, Western Australia.
Veterinary Medicine for fish.
W: http://www.thefishvet.com.au
E: thefishvet
P: +61 (0)421 822 383
Why is there a move towards national registration? The answers are sourced from http://www.daff.gov.au/animal-plant-health/animal/system/vets
Separate regulatory systems in each state and territory hinder the mobility of veterinarians within Australia, hinder interstate competitiveness, and inconvenience clients with interstate or national interests as well as those requiring particular veterinary expertise only available outside their own state or territory.
There is now ready movement of Australians and animals from state to state. Public policy has embraced the concepts of open markets, competition policy and mutual recognition by state and territory systems of qualifications and operations by other states and territories.
National recognition of veterinary registration has assumed increasing importance in the last decade with the growing need to remove obstacles to the delivery of cross-border veterinary services. In addition, one of the objectives of National Competition Policy is to allow greater competition within the veterinary services market. As production animal enterprises consolidate or specialise and performance animals travel to compete nationally, reforms which enable the integrated delivery of veterinary services on an Australia wide basis are vital to the profession meeting existing and future market demand for veterinary services.
Current arrangements no longer provide the most appropriate and efficient mechanism for regulation of modern veterinary practice, and do not accommodate ongoing technological advances and changes within the profession.
I had a flurry of questions about the blood testing. The most common one was, what is the minimum amount of blood we need in order to run a full biochemistry panel?
The minimum amount of blood we need is 0.5mL. Blood collection tubes come in all sizes and I’ve included a picture of the common sizes used (from left to right, 10mL, 5mL, 2mL and 1mL). The amount of anticoagulant to blood ratio shouldn’t be too much of a problem if running a biochemistry panel. It is only an issue if you’re wanting haematology since excess anticoagulant can rupture your cells, and too little will lead to a clotted blood sample. Of course there are a heap of other complications, but I’d best leave that to a specialist clinical pathologist to answer.
Collecting fish blood for testing can generate information on the health of the animals including states of inflammation (e.g. bacterial infection), viral infection, their immunocompetence and more.
Collecting blood from a fish can be likened to collecting it from the tail vein of cattle. I’ve uploaded a video (http://youtu.be/MPoqU6721_Q) demonstrating with an anaesthetised koi fish. In dorsolaterally compressed fishes, and if the needle is not of sufficient length, the needle may be inserted diagonally. Landmarks: midline, spinal column & level with the lateral line.
For reasons why we collect blood in fishes, check out more information on my blog – https://thefishvet.com/?s=haematology
In a race, what would you say to cheer a fish on?
GO! Rami!
(gourami)