Blood injections change color of chickens in a sex-specific and generational manner

The authors have obtained changes in the color of the plumage of white Leghorn hens by administering intraperitoneally to them the blood of gray guinea fowl. Studying five generations of Leghorn treated, they think that the injections act on the level of the reproductive organs.

 

Problems in the formation and transmission of heredity have given rise to some controversial work in recent years. Following the publications of Sopikov, Gromov, Kushner, within the framework of the research of Novikov, Bratanov, Benoît, Leroy, we undertook in 1957 the study of the behavior of the white Leghorn hen subjected to repeated injections of whole blood of gray guinea fowl (Numida meleagris). In 1958, at the 10th International Congress of Genetics in Montreal, we published our observations on the Leghorn Fo and F1. Here we report changes in plumage color over five generations.

 

Material and method. The plumage of the white Leghorn is a uniform white, the down of the chicks is more or less yellow. The plumage of the gray guinea fowl is more or less bluish gray, the background being speckled with white pearls.

 

Our test Leghorn strain Fo (45 male and 10 female) comes from a breeder who specializes in white Leghorns, who has been controlling the purity of his herd for almost 3o years. We have ourselves bred a control group whose F0 was composed of 25 male and 9 female. Of the nearly 600 animals obtained in five generations, we have not seen any notable modification of the standard.

 

We established a Leghorn control group treated with Leghorn blood, and a test Leghorn group treated with guinea fowl blood. Venous blood, collected aseptically, is collected on sodium citrate. Intraperitoneal injections begin between 10 and 30 days after hatching, the dose injected gradually increasing from 0.5 to 5 or 7 ml, depending on age. At the rate of one injection every 3 to 5 days for 6 to 7 months, the animals receive in each generation between 180 and 220 ml of blood. The injections were well tolerated. From 6 to 7 months, we practice artificial insemination.

 

At each generation, we separated the animals into two batches, only one continuing to receive blood. Given the small size of the premises, we had to, from 4 months, gradually eliminate part of the herd, so that at the time of fertilization we only had 20 to 30 female and about ten males per batch. Animals selected from each batch were randomly selected. All our animals are farmed.

 

Results. - A. Leghorn control group. – For five generations comprising nearly 4oo male and female, we observed no change from the control group and the Leghorn standard.

 

B. Test Leghorn group treated with guinea fowl blood - In F1, we reported that in 50 percent of the cases, the down of the chicks then the coat of the young male and female presented a dirty white tint, more or less extensive, but that the Leghorn white then reappeared. This phenomenon was repeated, in varying proportions, in subsequent generations. However, as soon as F2 was issued from F1, new plumage color changes occurred. It is first of all an ashen undertone, appearing at first on the head and neck, as a hood, then extending to the whole animal; this color is often accompanied by a golden reflection which predominates (without being exclusively localized there) on the level of the hood at the level of the male, of the back and the shoulders at the level of the female; the tint ashen is always more intense on the head and neck than on the rest of the body. The second modification consists in the appearance, without particular location, of feathers more or less stained with gray or black, with an irregular design. The third modification, rarer than the preceding ones, is manifested by more or less golden, buff or brownish feathers, often with some gray or black spots; we find these feathers more frequently in the males than in the females; their distribution predominates in the same places as the golden reflection. In general, one of the two tints, black gray or brownish gold, clearly predominates in a given animal. The down of the feathers remains white in the majority of cases, even if the coat is colored.

 

We were unable to establish a correlation between the presence of dirty white down in some chicks and the subsequent appearance of modified feathers.

 

In F2 from treated F1, out of 155 survivors male and female, we found a rooster with brown and buff feathers spotted with gray, and two hens with some feathers spotted with black.

 

In F3 from treated F2 (unmodified Leghorn F2), we found, out of 225 survivors, an ashen rooster, a rooster with a few black-stained feathers, three more or less ashy hens, one with gray-black stained feathers, a second with a brown-stained feather, and a hen with a few feathers stained with black.

 

In F4 derived from treated F3 (Leghorn F3 unmodified), we observed, out of 65 survivors, two cocks more or less ashy, four hens more or less ashy, one of which with certain feathers more or less black.

 

In F3 derived from F4 treated (unmodified and modified Leghorn F4), we obtained, out of 166 survivors, six cocks more or less ashy, two of which with the camail, the back and the brownish buff wings, some feathers stained with gray; 26 more or less ashy hens, four of which have some black-stained feathers.

 

Apart from a few fluctuations, these phenomena have remained stable, not disappearing with age, although the birds are generally no longer treated. We did not find any modifications in the offspring from the untreated batches of F1 and F2. having never been treated, gave rise to modified progeny which will be the subject of a subsequent Communication. Technical reasons did not allow us to breed the progeny of the untreated and modified batch F3.

 

Discussion and conclusion. It is possible to obtain stable changes in the color of the plumage of white Leghorns by repeated injections of gray guinea fowl blood. However, the males seem more difficult to transform than the females, and the susceptibility of the animals to the treatment is very variable. Some Leghorns were modified from the second generation, others only from the fifth. White Leghorn's blood has no effect.

 

The colored feathers do not apparently show any guinea fowl character. It is known that the white Leghorn has in its genetic heritage the black genes, inhibited by the dominant factor I; we can admit that the treatment, by revealing an ashy tint and black spots, disturbs the dominance of I. As for the golden, buff and brownish colors, their appearance is more difficult to interpret. It seems that factor I does not completely inhibit true brown (Rhode Island, New Hampshire type) when present in the Leghorn; we didn't see brown for the five generations of control and control Leghorns, that's more than 9oo animals. All of our observations do not seem to us either to indicate that it is simply a “salmon breast” or “red pile” phenomenon.

 

The modifications do not appear in the birds on which the injections are made, but in the following generation, without any treatment; in the same way this one does not exert a notable influence on the animal already transformed. It therefore seems that the treatment acts at the level of the reproductive organs. In a future Communication, we will see that the modifications observed are likely to be transmitted hereditarily.