Avian infectious toxic Hepatic enteritis: Tetrad injuries
Tetrad is understood as the set of four interlinked elements. In the pathology are considered symptoms or injuries linked to each other and although it is sufficient to obtain a triad in the case of avian infectious toxic hepatic enteritis (A.I.T.H.E.) is easily possible to obtain a consistent tetrad in injuries of yolk, blind, liver and gizzard of newborn birds and even in embryos of 18 days.
The yolk appear superior size to 8% of live weight and greenish color, the blind filled with a green liquid presents the gas hydrogen bubbles SH2 , the enlarged and jaundiced liver and gizzard stratum corneum with green injuries bile regurgitation and growth of producing bacteria SH2.