We’ve been able to visit about 10 breeders in Japan,  8 breeders in Niigata and one in Hiroshima. Here are a few of my quick impressions/observations so far based upon the visits to these few facilities:

• Most all of the fish I’ve seen are very healthy and vigorous. I was particularly impressed with the 1 year-olds (tosai). WOW!!, No I don’t have a good eye but from a health standpoint they looked great.
• Those that appeared “off” were not for sale.
• Most common diseases appear to be Anchor worm and Columnaris. The columaris is generally a problem when the fish come out of the ponds and move into the greenhouses.
• Sleeping disease is also a problem. This  disease, which is not well characterized, causes problems primarily with 1-2 year old koi in the Winter months.  The fish tend to lie unmoving on the bottom of the pond. They will swim when stimulated.
• Costia can also be a problem at times.
• The government requires testing for Spring Viremia of Carp and Koi Herpes Virus four times a year.
• Biosecurity concepts are understood and practiced to varying degrees as we see in the US. Most breeders have moved to locked facilities, appear to have separate sets of equipment for each facility and all we visited have foot baths at the entrances (however, actual use seems to vary). few places also have hand wash stations.
• A couple facilities have quarantine greenhouses into which recently harvested fish are moved for observation and to await testing. 
• All breeders seem to be very concerned  and try to be conscientious about biosecurity. The level of practice is often related to the actual amount of fish trade (economics). More trade in koi results in more funds that can be invested in biosecurity. Fish  or ponds that are ill or appear off are generally isolated, pulled from sale, or moved from the holding areas until resolved.
• As we see in the US biosecurity requires constant diligence by everyone in each facility and throughout. Everyone must: Think Biosecurity, Plan Biosecurity and Act Biosecurely, 
• I’ll post some photos of a selection of facilities and some more information/thoughts in the near future. This was just a few quick notes. All-in-all this has been a great learning opportunity for me and I really appreciate all the patience from the breeders with all of my questions. I have seen some beautiful fish!!!