Pacheco's disease it is named after the Brazilian veterinarian, Genesio Pacheco, who first came across the disease in 1929, in an outbreak affecting the turquoise-fronted amazon parrot, "Amazona aestiva". Initially, Pacheco's disease was thought to be a manifestation of avian psittacosis. The causative agent of the disease, a herpesvirus, was not identified until 1975. Pacheco's disease Pacheco's disease is an acute and often lethal infectious disease in psittacine birds. The disease is caused by a species of herpesvirus, Psittacid alphaherpesvirus 1 (PsHV-1), which consists of four genotypes. Birds which do not succumb to Pacheco's disease after infection with the virus become asymptomatic
Derzsy's disease Derzsy's disease Derzsy's disease is caused by Anseriform dependoparvovirus 1, in the "Parvoviridae" family. It affects geese and Muscovy ducks. The virus is shed in the faeces and thus transmission is horizontal, via the direct faecal-oral route and also indirectly via fomites. Vertical transmission is also possible. Clinical disease only occurs in young geese and ducks between birth and 4–5 weeks of age. Several genotypes have been described. The genotype is based upon the sequence of the VP3 protein. Acute disease leads to death in most birds between the ages of 7–10 days. Clinical signs are quite limited in those