| Popis: |
IT IS known (Lucas et al., 1946; Ringrose and Davis, 1946) that the hen can synthesize choline. It is unknown whether she is able to synthesize enough to meet her needs under all circumstances. Responses of various kinds to choline have been reported in laying hens. Abbott and DeMasters (1940) reported decreased egg production, increased mortality, aborted egg yolks and increased liver fat when diets low in choline were fed. Welch and Couch (1955) and Daghir et al. (1960) reported increased egg production when choline was added to the diet. Burns and Ackerman (1955) reported that egg size and choline content of the egg was increased by adding choline to the diet. Balloun (1956) reported that choline additions corrected erratic hatchability. Johnson (1954), Holmes and Kramer (1965) and Leach et al. (1966) found no beneficial effects from increasing the choline level of the diets used in their experiments. Nesheim et… |
