Conalbumin and serum iron transport in birds. II. Study in the turkey, duck and pigeon

Abstract
An analysis is inade of the possible intervention of serum conalbumin in the transport of serum iron in the turkey, the duck and the pigeon. It has been determined the content of serum iron and transferrin according to the methods of Ramsay and the conalbumin accord ing to an immunological precipitation method. The valúes obtained for conal bumin have been corrected in accordance with the cross percentage indicated by Wetter and coll. In the turkey the content of conal bumin is small and there do not appear to be differences between the two sexes. The values for serum iron and transferrin agree with those quoted in a previous work, in which, however, no study was niade of laying females. The conalbumin represents in this species 27 % of the transport capacity and plays a very secondary role, for the transferrin increases during the laying period and covers the necessities of transport. In the duck, on the contrary, the conalbumin must constitute an active mechanism, for the transferrin is cleary unable to cover the necessities of trans- port during the laying period, and the contení of the fonner protein represents 53 % of the total transport capacity. The inversion of values in this species had already been quoted in another variety, but on the present occasion this inversion has also appeared in the case of females not in the laying period. In the pigeon very high values have been observed in the serum iron in both sexes, as was already noted. The laying period causes an increase in serum iron, which increase is also accompanied by an increase in transferrin, and thus the paradoxical inversion noted in other species does not appear. The conalbumin is found in a very sinall concentration, and constitutes only 11 % of the total transport capacity. The intervention in the transport of the iron must be practically nil.