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does not appear. First page follows. Losses from obscure causes on certain California turkey ranges, where green feed is limited during much of the growing season, suggested the need for studies on vitamin-A deficiency in turkeys. The experiments reported herein were outlined to determine the possible relation of A-avitaminosis4 to turkey mortality and to obtain information concerning the effect on turkeys of various vitamin-A levels. A-avitaminosis in chickens has been fully described by Beach(1), Emmett and Peacock?(3), Seifried(10), Elvehjem and Neu(4), and many other investigators, so that the pathological changes in chickens are well established. Chicks were included in one experiment as a control on the methods used and as a basis for comparing A-avitaminosis in the two species. Scott and Hughes(9), using yellow corn as the source of vitamin A, showed that turkeys required more vitamin A than did chickens. This paper is concerned chiefly with the disease phases of the problem. Because published data on the vitamin-A requirements of turkeys are limited, the results on the comparative value of dehydrated alfalfa-leaf meal for turkeys and chickens are also included. Certain vitamin-A liver storage data collected in connection with the experiments have already been published by Guilbert and Hinshaw.(6)

IT IS common experience that chickens and other domesticated birds grow better if hatched at certain seasons than they do if hatched at other seasons of the year. Thus Goodale (1926) found that chicks hatched in the early part of the season grew more rapidly, to 30 days of age, than did those hatched later. Upp and Thompson (1927) likewise observed that there were differences in the rate of growth of chicks hatched at different seasons of the year. They conclude that weather has an influence on the growth of chickens. Somewhat similar results are reported in this paper for turkeys hatched only a few weeks apart. There is also a distinct indication of compensatory growth of the later hatched, initially slower growing birds. The same phenomenon has been demonstrated in the growth of razor clams by McMillin and Weymouth (1935). MATERIALS AND METHODS The data presented in this paper . . .

Lead poisoning has been increasingly recognized as a significant and major cause of bovine poisoning in Iowa during recent years [3, 4]. Data from the Iowa Veterinary Diagnostic Laboratory for the years 1965 through 1971 indicate an increasing number of lead poisoning cases in cattle, with 1970 as the peak year. From January, 1967, through June 30, 1971, 80 episodes of bovine lead poisoning have been confirmed by the Veterinary Diagnostic Laboratory. Of this number, 28 were recognized in 1970 alone. Lead poisoning is the single most common toxicosis in cattle in Iowa. In order to further delineate the incidence, clinical severity, sources, seasonal occurrence, and chemical results of affected and non-affected animals, this study was undertaken.