Turkeys

We have also been successful in breeding operations designed to get a small turkey of good conformation that is more suitable for family use than the larger kinds. The type of such a bird has been reasonably well fixed. The new turkey is named Beltsville Small White, so called from its place of origin, small size, and white color. Several thousand such birds of acceptable quality have already been produced. Hatching eggs have been distributed through State experiment stations to commercial breeders and considerable commercial production has resulted.

Beltsville Small White young toms weigh 12 to 17 pounds alive at market age. Young hens weigh 7.5 to 10 pounds—roughly about two-thirds the weight of mature standard-size birds. The body is compact, with much breast meat. The legs and neck are relatively short.

Artificial insemination has scientific and commercial possibilities in breeding chickens and turkeys. Department workers developed a simple way to obtain semen from chickens and turkeys and to inseminate the females. Fertility has proved high, and many breeders have shown interest in the method; but, except in turkeys, its commercial use has been limited. Research workers, however, use the technique to effect fertilization when birds cannot or will not mate naturally—to make crosses between bantams and larger varieties of chickens, for example.

Some researchers in nutrition employ the practice to fertilize the eggs of hens kept in batteries, so they can get information on experimental diets, fertility, and hatchability. A few poultrymen also use it for hens kept in batteries. Breeding hens are not usually kept in batteries, however, and many poultrymen prefer to mate a proved sire naturally with an unusually large number of hens, risking some infertility, rather than to undertake the additional effort.

Turkeys, particularly the Broad-Breasted Bronze, have shown considerable infertility, and some turkey raisers breed them artificially to overcome the fault. Other growers, encouraged by experiments at the Texas Agricultural and Mechanical College, have improved the reproductiveness of Broad-Breasted Bronze turkeys through genetic selection for well-balanced body conformation.

Broodiness in turkeys, as in chickens, cuts egg production, causes extra labor, and increases costs of producing points. We believe we can develop relatively nonbroody strains, and have started working toward that goal at Beltsville.

The Improvement Plan

Persons who prefer not to breed poultry but rather to purchase stock, either as day-old or larger birds, can do so now with prospects of obtaining much better stock than was available several years ago. Coordinated Federal, State, and commercial activities have been directed toward a wider use and better supervision of improved breeding methods. Examples of this trend are the National Poultry Improvement Plan for chickens and a similar plan for turkeys.

Use of males from bred-to-lay strains has been one of the principal factors responsible for the increase of 25 eggs a hen in course of the 10 years the National Poultry Improvement Plan has operated. A further increase is probable, because only about 30 percent of hens in hatchery-supply flocks are mated to males one or both of whose parents were officially pedigreed. Besides, as farmers get better stock they feed and manage their flocks better so as to get the most from their improved birds.

Bred-to-lay stock of chickens, representing any one of four progressive breeding stages, can be had from hatcheries and breeders. The stages, each with successively higher requirements, are : U. S. Approved, U. S. Certified, U. S. Record of Performance, and U. S. Register of Merit. The turkey plan stresses efficiency in meat production. For both species of birds, official flock and hatchery inspections and other forms of supervision provide reasonable assurance of obtaining the degree of quality desired.

As a further guide to persons seeking superior chickens, the Department of Agriculture now issues an annual directory of birds that have qualified for U. S. Register of Merit, the highest breeding stage.

Recognition is given to sires and dams on the basis of the productivity of their daughters, of which at least a third of those entered in the third-highest stage of the plan must have annual records of 200 eggs or more. Other requirements cover acceptable size of eggs and physical characteristics of the birds. More than 14,644 birds have thus far met the specified high standards. As evidence of the egg production to be reasonably expected from daughters of U. S. Register of Merit dams, officials in charge of the National Poultry Improvement Plan report that the average production of 28,248 such daughters was 208 eggs in 1944.

The use of airplanes for transporting hatching eggs long distances has prompted experiments to find out if high altitudes affect hatchability. They apparently do not. In our investigations we used reduced air pressures to simulate altitudes of 7,000 feet, 12,000 feet, and more, and discovered that the eggs under test, when incubated in the usual way, hatched after 3 days' exposure to a rarefied atmosphere equal to that at 15 miles above the earth.

Improving Egg Quality

Consumers prefer eggs with better shells, substance, and keeping quality; poultrymen like them because they cut marketing costs and losses.

We did some research on the thickness, porosity, and related characteristics of eggshells, as shown by shrinkage of their contents during storage; and found indications that the characteristics are inherited. Our studies, made with two different lines of chickens, also point to the improvement of shell quality by selecting families of breeding birds on the basis of blood lines that produce eggs that shrink little in storage.

Studies on the interior quality of eggs have shown that blood spots in eggs come from inherited faults. Poultrymen, therefore, are wise to cull their breeding flocks of hens that lay eggs containing blood spots, which cause great loss to producers, market agencies, and consumers. Our studies showed us the falsity of the common belief that handling birds, moving them about, or frightening them cause their eggs to contain blood spots. We found also that because many blood spots are very small (less than a thirty-second of an inch in diameter) candling is only about 50 percent efficient in detecting them—another reason for culling birds that are known to produce eggs with blood spots.

We also selected families of chickens on the basis of the rate at which the albumen in eggs deteriorates. One line developed in this way produces eggs which, when infertile, remain fit for table use after being held 2 weeks at 99° F. The albumen remains fairly thick in these eggs after such mistreatment, but another line of hens lays eggs that have no visible thick white after similar treatment. Poultrymen can use this method of selection in order to supply housewives with eggs of outstanding quality even if refrigerated transportation and holding facilities are lacking.

THEAUTHOR

Theodore C. Byerly is in charge of poultry investigations in the Bureau of Animal Industry. He is a graduate of the University of Iowa and for several years taught poultry husbandry at the University of Maryland. In 1943 Dr. Byerly received the Borden award for outstanding work in poultry research.