Koolie is a healthy breed. Breeders around the world make every effort to produce healthy dogs. We have a very wide genetic panel, developed specifically for koolies. We test our dogs at CEA PRA PLL DM CH CMR MDR1 NCL TNS CMC MH Cystinuria II. Therefore, the koolie is a mixture of very many shepherd breeds, we want to exclude all possible diseases that could inherit them. The koolie sometimes also dilute. It is worth remembering that there is no separate test for alopecia and dilute. A dog that has a dilute gene is marked as CDA. No it should be understood that there will be problems dysplasia of vesicles. Pleated spongiform syndrome is not common. There were a few cases in the koolies population. This is not fully investigated. We suspect that an additional nest will be needed for the disease to activate. Even if it does, it will not endanger the life of a dog and does not worsen his quality of life. It reveals a poor quality of hair in places where the color is diluted. Hair can be fragile or brittle and sometimes fall out. Test results are determined in three ways. Clear, carrier or affected. Clear means that both copies of the gene are clean. Carrier means one copy of the gene clean, the other copy is the carrier, Dog carrier will never get sick but can pass the gene on to offspring. You should never link carrier to carrier. You have to be particularly careful when choosing a breeding pair. The affected result means that the dog has both disease genes. It can be touched in the future. It should never be bred.