This phrase “It is well known that the higher the density of a given population the greater the potential is for pathogens to move between animals” is too simplistic for advanced shrimp farmers. It may have held water back thirty years ago as the industry was developing but it is not apt for current state of shrimp aquaculture.
Pathogens will move betwern animals regardless. It’s more about innate resistance and culture husbandry.
Disease talk needs to be put to one side as the number one issue is market price with this glut of global farmed shrimp – so much for diseases!!
“Farmers who saw the beginnings of the virus that causes WSS saw this even at low densities”…statement that negates the first.
Its not about virulence or density but all about relative carrying capacity of system and the applied husbandry.
If poorly managed this will induce stress that will lower resistance, allow for vius expressions and open the route for opportunistic bacteria that feed off weakened vulnerable shrimp.
Simple enough – and discharging water for neighbours to pickup is a structural problem that each farmrs should address.