The plasmatic proteins of the hen

Abstract

There are different works dedicated to the plasma proteins in hens realized. with free electrophoresis (6), paper electrophoresis (1, 2, 4, 5, 7, 11), agar gel electrophoresis (10), as well as for saline precipitation with Na2SO4 (3).

Our study presents an experimental aspect together with a brief review on this field, specially in connection with the sex and the laying period. The interest for these questions derives from the studies which we are carrying out about the serum iron and the transferrin (beta-l-globulin), which present special characteristics in the laying season (13, 14, 15, 16, 17).

We have studied two sera of chickens, 12 o£ not laying hens and 14 of laying hens, according to a salting-out method with Na2S2O3, proposed for the human serum (8). A series of concentrations of Na2S2O3 (to 30-50 gr %) with the difference from 1 gr %, has been prepared and moreover of 20 gr % and 25 gr %. In the fíltrate there has been determined proteins according to the biuret reaction (Weichelbaum’s reactive) against a calibration curve constructe with micro-kjeldahl.

The total proteins of the serum of different specimens of both sexes have also been determined (micro-kjeldhal). In the table III are included all the valúes of different authors, about the total proteins in this specie, where one can chek a certain relation with the state of the females.

The salting-out has permitted to notice the existence of 6 inflexion’s points in the curves (fig* > 2, 3), which are difficult to determine with precision in many cases because of the little difference between the values (table I). These points may be located in the following concentrations : 32, 34, 37, 40, 43-44, 45-47 gr %. In the human serum (8, 9), 3 principal points have been stated (30,7; 35,5; 44,1 gr %) which separate the four principal fractions of the serum (albumins, alfa globulin, beta globulin and gamma globulin).

The comparation of the results of the salting-out method and the electrophoretic control of the fractions (fig. 4), show how various inflexion’s points do not correspond to detectable electrophoretic variations. This may attribute to an electrophoretic technique which is little suitable and there may exist secondary inflexion’s points.

The protein fractions found by other authors (1, 2, 3, 4, 5) are of six or seven, except with the salting-out (3) which show four, and with immuno-electrophoresis (10), eleven.

The different fractions prove quantitative variations with relation to sexual maturity, and some authors (2, 4, 7) notice an increase of the beta-globulin fraction and a decrease of albumin, which in a more general form may put itself evidently in an increase of the relation albumin/globulin (18, 19).