Storey's Guide to Raising Chickens (64 page)

For all breeds, select cocks from your most productive hens. To maintain the depth of body needed in a good laying hen, look for breeder cocks with wide backs and an ample space between the keel and pelvic bones.

Breeding for commercial meat production shares much in common with breeding commercial layers: both are complex and highly specialized, concentrate genetics in a limited number of strains, and involve crossing strains. Among broiler breeders some specialize in raising sire lines, others in dam lines; many work with both. Commercial broilers may carry two-part hyphenated names, such as Peterson-Cobb. The first name represents the source of the sires, the second represents the source of dams.

The resulting broiler chicks grow faster than any you could hatch yourself. But if one of your purposes in keeping chickens is to produce meat as well as eggs, it makes sense to select your breeders for the good qualities of meat producers as well as layers.

The characteristics of good meat birds — rapid growth and efficient feed conversion — are unlike laying ability; these traits are quite heritable. Since a fast-growing bird passes the trait directly to its offspring, breeders are selected on the basis of having the greatest weight among flock mates at 8 weeks of age. At the same time avoid using as breeders any bird that grows significantly faster than is typical for the breed — those extremely fast growers tend to be the least healthy.

At maturity each bird selected as a breeder should weigh within ½ pound(0.25 kg) of the standard weight for the breed. Since meat is muscle, along with size goes a body type that accommodates good muscling — a broad breast; a spacious heart girth; a deep body; and a wide, flat back.

MEAT-BIRD CHARACTERISTICS

A chicken used to produce future generations for meat should have a broad breast, wide back, deep body, and spacious heart girth.

Trying to recover a rare or endangered breed differs from other breeding plans primarily in the number of chickens available to choose from. You may have to include inferior birds in your initial breeder flock, if they are all you can find of the breed you choose to work with.

To develop a sensible breeding plan, you must first identify the characteristics typical of your chosen breed. In selecting future breeders, the American Livestock Breeds Conservancy (ALBC) suggests you focus on six basic qualities:

Rate of growth
can influence the immune system. Extremely fast- or slow-growing chickens have less robust immune systems than chickens that mature at a normal rate for the breed. Maturity ranges between 12 and 18 weeks of age for most breeds; few mature earlier, but some breeds mature at a much later age. Jersey Giants, for instance, take 26 weeks to mature, and some longcrowers stretch it out to 18 months.

Mature weight
should fall within ½ pound (.25 kg) above or below the breed’s ideal weight. In most, but not all, breeds the ideal weight differs for cocks and hens.

Egg-laying ability
is of primary importance for laying breeds, of significance for dual-purpose breeds, and of some importance for meat breeds. Regardless of their expected rate of egg production, most breeds begin laying by 6 months of age.

Breed type
affects the size and shape of the internal organs and the distribution of flesh, thus affecting the breed’s suitability for the purpose for which it was originally developed. Type also influences adaptability to the environment, including climate.

Plumage color
is an indication of breed purity. Slight variations among family lines sometimes help identify the strain.

Fertility and vigor
give chickens the ability to withstand inbreeding, disease, and other challenges. Good indications of vigor are dominance in the peck order for young birds, longevity and fertility in mature chickens, and liveliness at all ages.

One of the major problems in working with a limited number of breeders is the loss of fecundity and fertility that typically occurs with inbreeding. The ALBC suggests you can retain the greatest degree of genetic diversity by keeping as future breeders the best representatives of each mating, rather than taking the traditional approach of keeping the best individuals overall. A five-year breeding plan for the recovery of endangered dual-purpose breeds is included in
Chicken Assessment for Improving Productivity
, available from the ALBC both in print and as a free download from their Web site.

Not all improvements occurring from one generation of birds to the next are due to inheritance. Some may result from good management or from what is sometimes called favorable accident. The amount of improvement attributable to inheritance is called heritability, and not all inherited characteristics are equally heritable.

In general, conformation characteristics are highly heritable, while production characteristics are not. To perpetuate traits with low heritability, you must select your breeders on the basis of family averages. To perpetuate traits with high heritability, you must select your breeders on the basis of individual superiority of those traits. Hence the evolution of two different breeding methods:
flock breeding,
which emphasizes the overall performance of a production flock, and
pedigree breeding,
which emphasizes individual characteristics.

Flock breeding is often practiced commercially and is also suitable for small-scale dual-purpose and layer flocks. Pedigree breeding is most often used for exhibition and sport strains and to implement the recovery of endangered breeds. Pedigree breeding itself has two common methods, individual mating and pen breeding.

Individual mating
may be accomplished either by mating a single cock with a single hen or by rotating one cock every 2 days among three or four individually penned hens. Individual matings may be tracked, or pedigreed, with certainty, since you know exactly which cock fertilized which hen’s eggs.

Pen breeding
involves mating a cock with a small number of hens together in one pen. It is similar to flock breeding except that smaller numbers of hens are mated to only one cock at a time. Unless you can identify which egg comes from which hen, pen-bred birds may be pedigreed only on the cock’s side. You may be able to positively identify parentage if each hen lays an egg of unique size, color, or shape. The only way to be absolutely certain of each hen’s identity is to trap the hen when she goes into a nest to lay.

The most common form of pedigree breeding is
linebreeding
, in which the influence of a superior sire or dam is concentrated by mating the bird to his or her best descendants. Pullets are mated to their sires or grandsires, cockerels are mated to their dams or grandams.

A good linebreeding plan includes four or more related families, starting with the best cock and four best hens available. Each family line consists of all the female offspring from one hen. The advantage to maintaining several lines is that if one of them fails to live up to your ideals, you can easily scrap it and start over with a new foundation female from within the same strain. If you are working with an endangered breed, maintaining several lines — including those that might initially produce inferior offspring — preserves genetic diversity.

In most cases you won’t know whether the matings you have chosen will prove successful until your third year of linebreeding, when both desirable and undesirable genes become concentrated. The third year is therefore the time when novice breeders are most likely to get discouraged and quit. The more separate lines you keep, the more you decrease your chance of getting discouraged by increasing your chance of producing one or more successful lines.

Double mating is used for breeds or varieties of show stock in which the male and female differ in type or color. It involves maintaining two different breeding lines, which may or may not be related to one another. To get good show cocks, match your best male to females that tend toward cock color or type, even though they themselves aren’t suitable for showing. To get good show females, mate your best females to a cock with hen color or type, even though he would not be suitable for showing. Exhibit only the top cocks from your male line and top hens from your female line.

HOMEMADE TRAPNESTS

Hook style:
A lightweight wooden door is hinged with #9 wire to swing freely. A hook made of #9 wire is set to hold the door open 6
inches (16 cm) above the nest floor. A hen entering the nest brushes the hook loose with her back. The nest must be about 6 inches (15 cm) deeper than normal, so the trap door can close behind the hen.