Archive for the ‘Fish Health’ Category


Sea Lice Innoculations

November 16th, 2008 by Andrew

As with any intensive livestock production, diseases and parasite infestation may lead to large scale losses causing financial loss.

Two types of sea lice Caligus and the larger Lepeophtheirus, recognised by their horse shoe shaped outer shell bite intensively farmed fish and damage the scales, cell tissue and mucous membrane.

This leads to a weakening of the fish’s immune system leaving it open to secondary infections and water accumulation in the tissue.

Hariolf Schmid (2003) suggests a method of solving this sea lice problem in fish farms by treating the whole school of fish with a semi-automatic injection device. This device involves directing the fish single file past an inoculation apparatus that weighs the fish and administers a correct dose to each fish.

An amazing invention! Details of the patent can be viewed here

permalink | trackback

Posted by Andrew Tags:
Posted in Fish Health | 1 Comment »


Real Time NIR Spectroscopy

November 14th, 2008 by Andrew

In recent years, the use of Near Infrared (NIR) Spectroscopy has been rapidly diffused throughout the aquaculture industry, replacing intensive and expensive wet chemical analysis to assist feed manufacturers to assess the nutritional content of feeds and the ingredients they comprise.

A novel application of NIR tehcnology has emerged through its use in assessing the highly variable nutritional content of fishmeal and other animal meals. Although I have been unable to track down the source, a leading researcher in the has told me that NIR is now being applied to provide real time analysis of meal batches as they are processed.

He explained that as the quality of meal batches varies wildly, samples of each batch are being analysed so that this information can be forwarded to the customer – aquafeed manufacturers – as the batch arrives at the mills.

These companies can then use this information to tweak their feed formulations to maintain product quality and ensure the nutritional content of their feed products.  This real time feedback brings some certainty to the task of formulating feeds using these highly variable meals.

If anyone can tell me where this technology is being applied in this manner, or who is doing it, I’d be very interested to hear it.

permalink | trackback

Posted by Andrew Tags:
Posted in Fish Health, Growth Inputs, Technology | 3 Comments »


DNA Vaccination in Aquaculture

November 13th, 2008 by Andrew

Leading scientists working in the field of fish vaccination in Norway consider as possible health and environmental consequences of DNA vaccines in aquaculture.

The understanding of potential consequences (risks) caused by environmental distribution of DNA vaccines, for instance, horizontal gene transfer may occur from transgenic DNA in vaccines to the recipient genome of micro-organisms or DNA vaccines may be released by faeces to the environment (Gillund et al, 2008)  

Basically, DNA vaccination is defined as the intentional transfer of genetic material to somatic cells for the purposes of influencing the immune system.

 The main problem faced by DNA vaccination, is need for research with risk-associated in it.  As scientists express diverging opinions regarding possible consequences of DNA vaccination in aquaculture, in the report, more specifically, the following issues were considered as relevant when conducting post market monitoring:

  • Changes in the fish population
  • Changes in the occurrence of fish diseases, or development of new diseases
  • Occurrence of rare or unexpected immunological effects
  • Integration into the genome of the recipient organism and inheritance to future generations
  • Impacts on humans health when consuming DNA vaccinated fish
  • Changes in the sea sediments and the population of micro-organisms

In Canada the IHNV DNA vaccine (Apex-IHN®), with the purpose of achieving resistance to infectious haematopoietic necrosis virus in Atlantic salmon, was approved for commercialization by the Canadian Food Inspection Agency in July 2005.

permalink | trackback

Posted by Andrew Tags: ,
Posted in Challenges, Environment, Fish Health | 1 Comment »


« Previous Page — Next Page »