Fatty liver hemorrhagic syndrome in hens overfed a purified diet. Selected enzyme activities and liver histology in relation to liver hemorrhage and reproductive performance.

A nutritionally adequate, purified diet was developed and used in studies to characterize selected aspects of laying hens in which fatty liver hemorrhagic syndrome (FLHS) was induced by overfeeding. Hens consuming the diet ad libitum or intubated with the diet in quantities equivalent to usual daily energy intake maintained normal rates of lay, did not become obese, and did not develop liver hemorrhage. Overfed hens had a 33% incidence of FLHS, as indicated by the presence of severe liver hemorrhage score, and displayed the full range of symptoms associated with spontaneous outbreaks of FLHS, including definitive lesions of hepatic reticulin. Among four groups of hens clinically classified according to rates of liver hemorrhage and egg production, there were no differences noted in total liver fat, liver fat concentration, or final body weight. Liver hemorrhage was associated with the degree of induction of liver lipogenic accessory enzymes. Serum enzyme activities indicate that overfed hens, unlike the overfed goose, retain hepatocellular membrane integrity. Overfeeding caused altered reproductive performance in 72% of hens. Alterations included erratic laying, increased incidence of double ovulations, shell defects, follicular collapse, and oviduct involution. Pattern of lay preceding necropsy seemed to influence follicle weight at necropsy. The data presented re-emphasize the interdependence among liver, ovary, and oviduct function in the etiology of FLHS.