The absence of pullorum-contaminated birds within the sublines versus purple-legged children deserves discussing

Probably, a man moms and dads ones specimens have been homozygous for the gene W. In the a dozen sublines away from 20, where men mothers were heterozygous (Ww), hens having pullorum situation were known. Alternatives throughout the inhabitants is being carried out contrary to the recessive gene w (reddish facial skin).

The Banned-and-Speckled Leghorn was an enthusiastic egg-laying reproduce but it’s a little too hefty. The fresh new alive pounds off 150-day-dated pullets was step 1.74 and that out of adult hens is actually dos.0-dos.1 kilogram. The latest alive pounds out-of cocks are 2.5 kilogram. Age maturity is 165 months. Yearly production is actually 220 eggs averaging 58 g. Champion layers give 270-290 egg a-year. Egg-shell try solution otherwise light; alternatives is occurring to own ointment the colour. Fertility out-of eggs are ninety-95% and you will hatchability 80%. Success rate of the young around 150 days of years is actually 95%; for the people it is 87%.

The characteristic feature of the new population is an excellent carcass appearance. In this trait they are superior to all known breeds of coloured chickens which carry the dominant gene E. Barred-and-Speckled hens, when mated with cocks of the C₁C₂ male parental form from the cross Hysex white, produce three-line hybrid layers, which are as good as four-way hybrids.

Barred-and-Speckled Leghorns try bred having enhanced eggs development and also for merging element regarding cross having men parental outlines out of Light Leghorns.

Black colored SPECKLED AUSTRALORP (Cherno-pestraya avstralorp)

An experimental population was created at the All-Union Research Institute of Farm Animal Breeding and Genetics by breeding inter se descendants of Black Australorps which had been injected intramuscularly with blood from Barred Plymouth Rocks. The total volume of components injected during 11 months amounted to 330-380 ml per bird. The 1962 experiment resulted in 1093 offspring (F₁). Among them were birds in which the juvenile moult produced, instead of black, a partially or completely white plumage. The number of chickens (F₁) with depigmentation in groups which received injections of the whole alien blood, plasma, and blood elements was 4 (2.2%), 2 (1.9%) and 1 (0.9%). The control group had no specimens with white plumage.

Mendelian study revealed that the brand new light colour of the new plumage from inside the chickens gotten within this experiment try determined by the end result away from the new partial-dominant gene De with 40% penetrance during the heterozygotes (Dede). The term off depigmentation varied considerably inside the private chickens.

Experimental birds in addition to demonstrated a significant type on down the color of your embryo. And additionally black colored, that’s normal to own Australorps, nearly white is observed, with quite a few changes between the two. Providing this really is a good recessive character, brand new mating regarding heterozygotes will be bring 25% regarding instances. The new departure of the noticed amount (7) about theoretically requested (8-9) appeared as if perhaps not statistically high.

Wild birds which have white embryo down was bred inter se and you may entered with chickens which have most other down the color. For the 1973-74, over 5000 such as girls had been hatched. Their decisive plumage is black colored having a little depigmentation. It was confirmed you to definitely white color of the new embryo off is actually passed down while the a recessive reputation when considering black and that it’s subject to the newest autosomal gene sp (spot). Brand new gene sp prevents melanin synthesis in the homozygotes not just in individuals generations Gay dating of your own plumage, plus on shanks. So it improves notably the look of Black colored Speckled Australorp carcasses (dede spsp), compared to brand-new breed – Black Australorps (dede SpSp).

Two F5 lady chickens brought 33 chicks eight (21%) of which was indeed white that have a tiny black-spot on right back

After that reproduction was used with this specific class and you will raising of birds carrying the De- allele is actually abandoned. Wild birds with light definitive plumage (DeDe SpSp) had eyesight faults followed closely by outward indications of exophthalmos and you may anexophthalmos.