History of Chickens in the U.S.

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History of Chickens in the U.S.

Prior to Industrialization

A 1924 account of a Kentucky extension agent describes chicken keeping as follows:

"Most people lived on farms or in small towns. Income was from general farming, coal mining, lumbering, and general merchandising. Mongrel chickens were kept on most farms, with little attention given to improvement. About the extent of trying to improve the flock then was to swap hatching eggs with neighbors. Poultry raising was considered women's work and was the chief source of "pin money" for the housewife. Chickens were raised much as our forefathers did, by natural incubation and raising chicks with hens in brood coops. Housing was poor; trees served as roosts on many farms. Feed consisted of grain (corn mostly) which the farmer gave grudgingly and what the flock could pick from free range around the homestead... There were no brooder houses and no brooders... No poultry feed had ever been sold. No chicks had ever been bought... No merchant could be convinced to sell poultry feed."[1]

The extension agent reports that after five or six years of extension efforts to convince farmers to change their practices.[2] An extension agent in Maine that, "prior to World War I, anyone in that state who had more than 100 chickens was considered to be quite heavily in the "chicken business.""[3]

Prior to industrialization, many farms did not even have chicken coops: "Little thought was given to either management or housing. In summer, the chickens often roosted in tree, as their progenitors had done for centuries, and in winter they found shelter in sheds and stables along with other livestock.[4]

Industrialization of Chickens in the U.S.

Small farm flocks were the norm in America until after World War II. The transition from small farm flocks to large, commercial operations began on the coasts but did not reach the Midwest until the 1950s. The commercial broiler industry developed rapidly in the south, followed quickly by the commercial egg industry.[5] In 1930, over half of American farms with chickens had fewer than 50 each.[6] With industrialization, there was a drop in labor needs. In California, the labor required in 1970 was just one-tenth of what it was in 1925.[7]

Breeding

For more information, see the article on American Chicken Breeds

Artificial Incubation, Brooders, and Commercial Hatcheries

Although artificial incubators have been used as far back as ancient Egypt, the development of the modern incubator and commercial hatchery began around the late 1800s and early 1900s.

"The change to artificial incubation was slow... Some breeders believed they could produce healthier and stronger chicks by natural methods. Pullorum disease was more readily spread in incubators than under hens and no doubt gave rise to the belief that chicks produced by artificial incubation methods were not as healthy as hen-hatched chicks."[8]

The struggle with Pullorum disease led to the failure of many hatcheries.[9]

Several technological developments were needed too. For incubation, what was ultimately required was a forced-draft incubator that circulated the air in a uniform fashion to keep the temperature the same throughout the machine.[10] Commercial hatcheries required one that could incubate a large number of eggs at once.

A second issue was developing a "chick box" - a package that could house the chicks as they made their way to their new homes with whoever purchased them.[11]

Another early issue, prior to 1913, was opposition from breeders of fancy or exhibition poultry, who sold hatching eggs at higher prices than the hatcheries sold day-old chicks and resented the competition.[11] Opposition petered out after an attempt to pass a resolution against the sale of chicks under four weeks of age at the 1913 American Poultry Association meeting.[12] This underscores a larger rift between those who wished to move in a utilitarian direction, breeding and selecting for traits like egg production, and those who saw breeding as an art to produce aesthetically perfect chickens.

Once hatched, chicks needed heated brooders for their first several weeks of life to fill the role that would have been performed by a mother hen. Developing a brooder that kept the chicks at the required temperature and met their other needs was another hurdle to clear, both in commercial settings with large flocks and in small scale settings like homes and farms.

Ultimately, the shift to purchasing chicks from hatcheries instead of hatching them on the farm aided in the simultaneous move from "mongrel" chicken flocks to flocks of pure-bred chickens.[13]

By the 1970s, poultry production is so specialized that "some breeders produce only a pullet to cross with a cockerel produced by another specialty breeder. Most hatcheries that produce broiler chicks do not produce egg-type chicks and vice versa."[14] Broiler hatcheries were owned by vertically integrated corporations like Tyson Foods, Pilgrim's Pride, or Perdue Farms, but commercial hatcheries are still mostly independent of the large egg operations they sell chicks to.

Following a peak in 1934, hatcheries grew and consolidated.[15] In addition to other factors, one reason each hatchery increased production during the middle of the 20th century is because they began hatching chicks year-round, whereas in the 1920s and 1930s, they only operated in the spring because that was when farmers purchased chicks.[16]

Nutrition and Feed

An 1873 book on chicken keeping recommended feeding baby chicks 1 part chopped up hard boiled eggs mixed with two parts bread crumbs, moistened with milk. An 1893 publication recommended maggots, mealworms, and fresh fish as feed for chickens.[17] Already, by the second half of the 19th century, there was a move to a more scientific way of feeding chickens. Wright, author of the 1873 Illustrated Book of Poultry, provides one of the first known tables of macronutrients (carbohydrates, protein, fat, fiber, and water) for foods commonly fed to chickens based on data from 1867. Later calculations show the table is largely correct (or close to it) but "no one really knew how much of each nutrient was required and no one knew about the various vitamins that would be needed for good growth or egg production," limiting the usefulness of such a table.[18]

Some of the earliest commercially sold livestock feeds came from waste products previously dumped in rivers, sometimes after livestock accidentally ate them and farmers noticed good results. This began as early as 1888 with Buffalo Feed from Buffalo, NY.[19]

Before 1900, chickens were fed tables craps, corn, wheat, oats, barley, liquid milk products, buckwheat, "beef scrap press cake" (a waste product made from beef scraps that were cooked and the fat was pressed out), oystershell, and salt.[20]

Early efforts to scientifically formulate poultry feed began in the 1890s, but little progress was made until after vitamins were discovered in the early 20th century.[21] The discovery of vitamin D in particular "enabled the broiler industry to get started on a year round basis and in total confinement."[22]

Products added to chicken feeds between 1900 and 1910 included: bone meal, green bone, linseed meal, takage, wheat bran, and wheat middlings. In the decade ending in 1920, alfalfa mea, corn gluten meal and feed, dried buttermilk, dried brewer's yeast, fish meal, ground limestone, meat scrap, and sprouted grains were added. Between 1920 and 1930, cod liver oil and dried skim milk was added. Beginning in 1930 to 1940, chickens were also fed dried whey, manganese sulphate, milo, and soybean oil meal. In the 1940s, D Activated Animal sterols, Dicalcium phosphate, liver meal, and Riboflavin supplements were added. During the 1950s, antibiotics, antioxidents, arsenic compounds, distillers dried solubles, feather meal, fermentation solubles, fish solubles, "inedible" animal fats, methionine, and vitamin B12 supplements were added to chicken feeds. In the 1960s, complete vitamin supplements, complete trace mineral mixtures, and lysine were added to chicken feeds.[20]

In the 1950s, scientists had finally identified enough of the necessary components of poultry nutrition that "highly purified diets could be used with success." Additionally, antioxidants were used in poultry feed to keep fats from going rancid.[23] In 1956 or 1957, the feed industry began using Linear Programming, a way to calculate the cheapest way to combine ingredients and additives to produce a diet meeting all of a chicken's nutritional needs.[24]

From Farms to Confinement

Over the course of the 20th century, chickens went from spacious accommodations on farms to total confinement as follows:[25]

YearSquare feet per birdType of HousingSize of Bird
19194 to 4.5FloorLarge
19453.25 to 5.5FloorLarge
19452.75 to 4.0FloorSmall
19673.0 to 4.5FloorLarge
19672.5 to 4.0FloorSmall
19511.0 to 1.5CageSmall
19660.5CageSmall

As chickens moved into crowded confinements, waste disposal became a problem (as did flies). Manure lagoons and oxidation ditches were used as "intermediate steps in manure disposal" to cut down on flies. In the mid-1960s, systems that collected droppings in containers of flowing water were tried. They aimed to "flow away" the manure into a digestion chamber. However, they were problematic due to both odor and cost. Others spread manure on pasture or dried it (using various methods of drying) and sold it to gardeners. By the 1970s, some called for "recycling" chicken manure by feeding it back to chickens or to ruminants.[26]

Disease

A chronicle of common diseases and cures in the 20th century reads as follows:[27]

"In 1948, a chronic respiratory disease, called PPLO was common. In 1960 a small bacteria (M. Gallisepticum) was established as the cause. It is now simply called CRD in chickens and sinusitis in turkeys. When streptomycin became available in the late 40s it proved to be very effective...
"Bluecomb (nonspecific infectious enteritis), and sinusitis were recognized as problems at about the same time and responded to the same drugs.
"Respiratory diseases of viral origin began to be identified as better methods of isolation were developed.
"Knowledge on fowl pox (diphtheria) came first (1910-13) and gave an insight as to what could be done with vaccination. At first dry scabs from the combs of otherwise healthy birds were ground into a powder and packaged in glass vials for almost indefinite keeping.
"For use, the powder was suspended in water and a little of this was rubbed into a few feather follicles on the leg. A durable immunity developed, and this method came into general use through the 30's. By 1966 some 300 million doses were prepared, with an additional 100 million doses of the pigeon pox variety..."

Timeline

  • 1700s-1800s: Ships bring chickens with them as food for crew and passengers. Many that had not been eaten during the voyage were sold or traded at ports in the U.S., introducing new gene stock to U.S. chickens. No breeds exist but certain places are known for unique "styles" such as large reddish chickens in Rhode Island that were ultimately developed into the modern Rhode Island Red.[28]
  • 1830:
    • Start of breeding of Red chickens around Narragansett Bay in Rhode Island.[29]
    • Start of importation of chickens to the U.S. from Asia. They are called "Cochin Chinas," "Brahma Pootras," "Shanghais," and "Chittagongs."[30] Ultimately, the Shanghai breed was developed into modern day Cochins, the Brahma Pootras into Brahmas, and the Cochin Chinas into Langshans. All three Asiatic breeds grew to large sizes and were well adapted to confinement.[31][29]
  • 1835: Java chickens first imported to U.S.[29]
  • 1840: First poultry census in U.S. An estimated 98,984,232 poultry are in the U.S.[29]
  • 1841: Dorking chicken imported to the U.S.[29]
  • 1842: First recorded incubator exhibited in the U.S.[29]
  • 1843:
    • First poultry book is printed in America, The American Poultry Book by Micajah R. Cock, a pseudonym for C.N. Bement.[32]
    • The first American incubator is patented.[33] (Artificial incubation has been practiced elsewhere in the world for 2000 years.)[34]
    • First importation of Cochin breed.[35]
  • 1847: Dominique and Javas crossed, "providing the foundation for the development of Barred Rocks."[35]
  • November 15, 1849: The first chicken show is held in Boston. More than 10,000 people attend and chicken shows become popular.[36]
  • 1853: First record of White Leghorns in U.S.[35]
  • 1856: Barred Plymouth Rock breed developed.[37]
  • 1859: Houdan chicken imported to the U.S.[37]
  • 1860s: A new innovation in poultry breeding is introduced: the toe-punch. It helps breeds distinguish one chicken from another by the combinations of small holes punched in their toes.[38] The name Leghorn is given to an egg-producing variety previously referred to as an "Italian" chicken.[31]
  • 1865: Charles A. LaMont is the first to invent a method of drying eggs.[37]
  • 1865-1866: In the UK, the London Poultry Club compiles standards for breeds of chickens.[39]
  • 1867: An American edition of the British Standard of breeds is published by A.M. Halsted.[39]
  • 1869: The Plymouth Rock is first exhibited by Rev. D.A. Upham of Connecticut.[37]
  • 1869: The first trap nest is patented. It allows breeders to hold a hen in a nest after she laid her egg so they could tell which hen laid which egg.[38][40]
  • 1870s: The Wyandotte breed is developed in the Silver-Laced variety, but it is initially called a Sebright Cochin.[41]
  • 1870:
    • The Poultry Bulletin, the first monthly poultry publication is published.[39] The first hatchery is established, selling farmers two to four week old chicks.[42]
    • Black Jersey Giant breed developed.[40]
    • "Poultry raisers begin to show interest in egg numbers and quality, in addition to feather color and confirmation."[40]
  • 1871:
    • A second American edition of the British Standard of breeds is published by Halsted. Due to dissatisfaction with Halsted's version, W.H. Lockwood publishes a different Standard.[39]
    • William E. Lewis publishes a book on chickens that lists common diseases of the day: "apoplexy, bone fracture, black rot, catarrh, feather eating, frost bite, cholera, crophound, curly toes, dysentery, diptheria, egg-bound, gapes, gout, legweakness, lice, liver and gall enlargement, rheumatism, roup, scurvy legs and verigo."[43]
  • 1872: "A commodity exchange for the trading of cash eggs is chartered as the Butter and Cheese Exchange of New York." It became the New York Mercantile Exchange in 1882.[40]
  • 1873:
    • The American Poultry Association is established "to prepare and authorize a Standard breeding guide."[40]
    • John Graves advertised for sale incubators and chicks (two to four weeks old) in Boston, MA, representing the beginning of what would become the commercial hatchery.[44]
    • Wright publishes The Illustrated Book of Poultry and includes a table of macronutrients in various foods commonly fed to chickens, which may be the first of its kind. However, even with relatively accurate information about fat, protein, and carbohydrate content in various feeds, nobody knew at the time how much of each chickens needed to eat. Wright also recommends a ration for baby chicks that remains popular for the next 40 years.[45]
    • Wendelin Weis patents an egg case filler that will keep the eggs safe during transport and storage.[40]
  • 1874:
    • The American Poultry Association publishes the Standard of Excellence, its official guidebook for poultry judging in North America. It contains 46 breeds.[46]
    • Chicken wire is first advertised. Previously, old fishing nets were sometimes used to confine chickens, and chicken wire is patterned on fishing nets.[47]
  • 1875:
    • The American Poultry Association publishes the second edition of the Standard of Excellence, expanded to include 79 breeds and varieties.[46]
    • White Plymouth Rock introduced.[47]
    • Connecticut is the first to establish a State Experiment Station.[47]
  • 1877: W.C. Baker operates a poultry farm in Creskill, NJ with a capacity for 2000 laying hens and a quarter million broilers per year.[47]
  • 1878: Charles A. LaMont begins commercial business with his egg drying process.[47]
  • 1880:
    • C. Nisson custom hatches and sells chicks in California.[44]
    • Dr. D. E. Salmon reports the occurrence of fowl cholera in the U.S.[48]
  • 1881: The Eureka Incubator, the first incubator with an automatic regulator, is sold.[49]
  • 1883:
    • The Wyandotte breed is given its name.[41]
    • The USDA establishes a Veterinary Division to control animal diseases.[48]
  • 1884: An egg production research study is done in New Jersey.[50]
  • 1886: Poultry feeding experiments are carried out in Maine.[50]
  • 1888:
    • The name of the Standard of Excellence is changed to the Standard of Perfection.[46]
    • "Buffalo Feed" is one of the first specialized livestock feed produced. The residue of corn processed in a corn mill in Buffalo, NY was dumped in a river. During a flood, the discharge was deposited on land where cows ate it, and farmers noted an increase in milk production. The plant began selling the product as a livestock feed.[51]
  • 1889:
    • Poultry Culture by I.K. Felch is published, recommending a feed ration for chickens of "excelsior meal" made of 20 lbs corn, 15 lbs oats, 10 lbs barley, and 10 lbs of wheat bran mixed with 1 quart sour milk or buttermilk, salt, molasses, and 1 qt water containing 1 heaping tsp baking powder. The mix was to be formed into cakes and cooked before feeding them to the chickens.[52]
    • Dr. E.C. Waldorf of Buffalo, NY is the first to use artificial light to increase winter egg production.[53]
  • 1890s:
    • Rhode Island Reds become popular, but are not yet accepted as a standard breed. However, their precursors have been around in the Rhode Island, Eastern Connecticut, and Southern Massachusetts since the 1840s.[54]
    • Several land grant universities publish bulletins with instructions on keeping poultry, and some offer short courses on poultry keeping as well, a trend that continues and expands in the next decade.[55] In the early years, and in some cases even past 1940, poultry courses were placed in the Home Economics department, as chicken keeping was seen as the job of the housewife.[56]
  • 1890: Dr. Wheeler at the Geneva Experiment Station in New York begins poultry research.[57]
  • 1892:
    • Day-old chicks are first shipped by overnight express.[58]
    • Discovery that laying hens need calcium.[59]
  • 1897:
    • Gilbert Gowell in Maine and Horace Atwood in West Virginia begin experimental work on poultry.[57]
    • Discovery that birds need thiamine.[59]
  • 1898: The first "satisfactory" trap nest is made by Eureka Nest, invented by A.A. Silberstein of Framingham, MA.[60]
  • 1899:
    • A farmer installs gas lights in his poultry house..[58]
    • Leo F. Rettger identifies Pullorum disease.[61] It was a common killer "from time immemorial" of baby chicks. "There was always a diarrhea with white urates on top. So it became known as White Diarrhea." With the discovery of the bacteria, the name changed to Bacillary White Diarrhea (BWD). In the 1930s, the bacteria was officially named Salmonella pullorum, and that is when the disease received the name pullorum.[62]
    • Meat scrap is shown to be better for ducks than plant protein.[59]

1900s

  • Early 1900s: Breeders begin to take an interest in utility - the production value of chickens - in addition to their aesthetic features.[63]
  • 1902:
    • A failed attempt is made to turn the American Poultry Association to an organization focused on "the excellence of breeds and varieties and upon the licensing of qualified individuals to make selections in the showroom" into a trade association.[64]
    • Hatcheries are now common and the baby chick business is growing.[64]
    • A 1902 book The New Book of Poultry by Lewis Wright lists 35 hatcheries with egg capacities of 4,000 to 25,500. The latter uses 85 incubators each with a capacity for 300 eggs.[65]
  • 1903: The first dry mash poultry formula ever sold as a complete poultry feed is developed. It is used in another first - the first research farm test feeding.[66]
  • 1904:
  • 1905: James G. Halpin receives a B.S. in poultry at Cornell University, making him likely the first student to receive such a degree in the U.S.[67]
  • 1906:
    • Michigan State University established a Department of Poultry Husbandry. It was likely the first such department in the nation.[68]
    • Lamp-heated multilevel cabinets are sold as brooders by Paradise Brooder Co. of New York. "These were one of the earliest examples of what we today call batteries. The manufacturer claimed their advantages included keeping separated chicks of different ages and from different matings."[69]
  • 1908:
  • 1909: The American Feed Manufacturers Association is formed.[59]
  • 1910: The first poultry extension agent with a federal appointment is hired, part time.[74]
  • 1912:
    • Casimar Funk theorizes on the existence of vitamins.
    • Multi-story chicken houses begin to appear, such as a two-story house for 1000 hens on [[Yesterlaid Egg Farms][ in Missouri.[75]
  • 1913:
    • Strong organized opposition to hatcheries' practice of selling day-old chicks comes to an end. It was previously opposed by breeders of fancy or exhibition poultry, as hatcheries undercut their prices by selling day-old chicks for less than the breeders sold fertile eggs. Breeders tend to prioritize qualities that would help a chicken win in a show, whereas hatcheries focused on utility factors like egg production.[12]
    • An antigen is developed for pullorum disease. The test for the disease took 24 hours and required handling the entire flock twice - once to obtain a blood sample and a second time to cull infected birds.[76]
  • 1914:
    • The American Association of Instructors and Investigators in Poultry Husbandry begins publishing a journal called the Journal of the American Association of Instructors and Investigators in Poultry Husbandry.` Its name is changed in 1921 to "Poultry Science."[72]
    • Land grant universities use dry mash diet. In 1914, University of Wisconsin uses a mix of 100 lbs yellow corn meal, 100 lbs wheat bran, 100 lbs wheat middlings, 50 lbs ground oats, 50 lbs barley sprouts, 50 lbs beef scrap, 25 lbs linseed oil meal and 4 lbs salt. The scratch grain was 2 lbs wheat, 2 lbs corn, and 1 lb oats.[77]
    • Vitamin A discovered in butter and egg yolk.[59]
    • Discovery that corn protein is deficient in lysine and tryptophan.[59]
  • 1915:
  • 1916:The International Baby Chick Association is founded.[64]
  • 1917: The International Baby Chick Association appeals to the U.S. Post Office to accept live poultry for shipment via parcel post. Previously all transportation of chicks was via local transportation and railway express, but it had become problematic: "Though the War Department took over the operation of the express companies, transportation was so snarled that thousands of chicks died in transit." Due to the "urgent demand for food" during World War I, the post office accepted shipments of chicks.[79]
  • 1919:
    • "An organized effort to promote poultry breeding and improvement work among breeders and commercial flock owners" begins in Canada, extending to the U.S. a year later and spreading rapidly.[80]
    • Discovery that calcium is needed for poultry.[59]
  • 1920s:
    • Crossing breeds becomes popular in the commercial industry[81] Feed manufacturers "who were just getting established" begin to operate many research facilities on experimental farms. They also use the farms as demonstration sites where farmers were invited for field days and tours.[66]
    • Demand grows for purchasing chicks from hatcheries. However, hatcheries struggled to supply the high demand and, in some cases, sent poor quality chicks to customers. "As a result, mail-order chicks received a "bad" reputation."[82] Automobile and rail transportation had increased by this time enough to allow more farmers to receive chicks by mail or drive to pick them up from hatcheries themselves.[83]
    • Early efforts to improve quality of breeding stock and baby chicks develop on a state by state basis. They are concerned with breed improvement and control of Pullorum disease.[84]
    • Patent medicines and folk cures for chicken ailments become common.[85]
    • In the mid-20s, veterinarian J.E. Salsbury begins practicing in Charles City, IA. By 1930 he employed a large team for research and sales. He created an educational program, developing literature and using it to teach dealers and large hatchery operators. He was inducted into the Poultry Industry Hall of Fame in 1968.[86]
    • A test is developed to detect tuberculosis in poultry but it never became popular. "T.B. was confined largely to northern states, and as poultry management adopted the practice of close culling and not keeping birds much beyond a year of age, the disease has practically disappeared."[87]
    • Forced air incubators in hatcheries spread germs among chicks as they hatched. A big killer of baby chicks was pullorum disease, which was carried by apparently healthy hens and transmitted to their eggs. Infected chicks could spread the disease to uninfected ones hatching in the same incubator. Many died shortly after birth or during shipping.[88]
  • 1921: One of the first organized efforts to control pullorum disease in chickens was started in Maine.[3] However, doing so did not become popular throughout the country because of the heavy labor required to test the flock and then return 24 hours later to cull the infected birds.[76]
  • 1922: Discovery that cod liver oil prevents rickets in chicks.[59]
  • 1923:
    • The first electrically heated and electrically regulated "mammoth" incubator is invented.[89]
    • Discovery that vitamin A is needed by chicks.[59]
  • 1923-1924: Tests in Massachusetts show only 27.3% of 139 flocks tested are free of Pullorum disease.[9]
  • 1924: Discovery that vitamin A is needed for hens.[59]
  • 1925:
    • Discovery that Vitamin D can be produced by irradiation and that it is needed by hens.[59] Prior to the inclusion of vitamins A and D, many large scale poultry operations failed because "vitamin requirements for poultry were unknown."[90]
    • Dr. Morley A. Jull of the USDA holds a Standardization Conference to draft a uniform plan to improve poultry breeding throughout the U.S. It is called the "Manhattan Plan."[80]
    • Between 1925 and 1930, alfalfa meal, dried milk products, and, "in a limited way, soybean meal began" to be fed to chickens. "Cod liver oil was usually mixed with the feed, but in some instances individual dosing was used."[91]
  • 1926: Discovery that calcium is needed by chicks and sodium chloride (salt) is needed for chickens.[59]
  • 1927:
    • A new test for pullorum, called the plate test, is developed by BAI.[76]
    • Extensive study of coccidia (the cause of coccidiosis begins. Nine species are identified by 1964. A long list of management techniques and drugs are used to try treating or preventing it throughout the decades, many without success (particularly in the early years).[92]
  • 1928-1929: By this time, Massachusetts finds over half (55.2%) of 413 flocks tested are free of Pullorum disease (compared to about half that five years before).[9]
  • 1929:
    • Discovery that iron and copper are needed for chicks. Discovery of the ratio of calcium to phosphorus needed for chick nutrition. Chicken feed is first made in pellet form. A procedure is developed to find a numerical rating for biological values of protein for chickens.[93]
    • The Ohio Agricultural Experiment Station publishes research on keeping laying hens in cages. It is the first to do so.[94]
  • 1930s:
    • Availability in more rural areas provides farmers with another heat source (heat lamps) for brooders.[69]
    • Hatcheries began offering "started chicks" at 1, 2, or 3 weeks of age (as opposed to selling them as day old chicks). "The idea was that most chick losses normally occurred during the first few days of a chick's life" and "a started chick was more likely to survive." The practice continued until "the widespread disappearance of the farm flocks" in the 1950s.[95] Another explanation is that shipping the started chicks became impossible following "the discontinuance of the rail service used by Railway Express in the 1950s."[96] By the 1970s, it was possible to ship started chicks again via REA Air Express but the costs were prohibitively expensive.[97]
    • Chicks can be raised commercially year round for the first time. Previously, rickets was a problem due to vitamin D deficiencies.[98]
    • Up until the 1930s, experts recommended keeping chickens in small units to control disease.[99]
    • American veterinary colleges add poultry to the curriculum in the late 1930s and "only in a minor way."[100]
  • 1930:
    • Discovery that iodine is needed by poultry.[93]
    • Chicken feed still contains meat scrap, dried milk product, extra limestone and cod liver oil.[101] "Even though a number of discoveries were made between 1930 and 1936 the rations used were still very similar." Even after discoveries were made, it took time to translate them into a feed that could be used commercially.
    • First attempts to keep hens in battery cages, usually three decks high. It was not very successful because "not enough was known about the need for heating and ventilation." However, in California, and Hawaii, an outdoor cage system with one chicken per cage was developed in the mid-1930s. The next step was placing the cages back to back. Then they discovered it was cheaper to house two hens per cage, then three, and in some cases, four. In all cases, the cages were 12"x18" and 15" to 18" high.[102]
  • 1931: The Rapid White-Blood Test is the first practical field test that commercial operations can use to test for Pullorum disease.[9] Unlike the previous test method, it takes only one minute and requires handling the flock only once instead of twice.[76]
  • 1932:
    • Discovery that soybean meal needed to be heated to destroy harmful enzymes prior to feeding it to chickens.[103]
    • Feed is produced in the form of "crumbles" for the first time.[93]
  • 1933:
    • The Japanese method of sexing day-old chicks is introduced in the U.S.[84]
    • Discovery that laying hens need salt in their diets.[93]
  • 1934:
    • The International Baby Chick Association published the "International Poultry Guide for Flock Selection," a handbook for selective breeding of popular varieties. It focuses more on utility than exhibition qualities.[104]
    • The number of hatcheries in the U.S. reaches a peak of 11,405 hatcheries producing 525 million chicks.[15]
    • Discovery that chicks need vitamin K in their diets.[93]
  • 1935: The National Poultry Improvement Plan is established. It is a uniform plan that helped control Pullorum disease and later other diseases (S. pullorum, S. gallinarium, S. typhimurium, and M. galliseptum.)[84]
  • 1936:
    • The protein arginine is shown to be essential in chick nutrition.[105]
    • Discovery that manganese prevents perosis in chicks.[93]
  • 1937: Discovery that manganese is essential for "hatchability." That is, unless it is included in the hen's diet, her eggs cannot hatch.[93]
  • 1938:
    • The Federal Trade Commission developed trade practice rules for the baby chick industry.[106]
    • Discovery that thiamine is needed in the diet for chicks and that riboflavin is needed in the diet for hens.[93]
  • 1939: Discoveries that pyridoxine and pantothenic acid are essential for chick nutrition and pantothenic acid is essential for hen nutrition.[101]
  • 1940s:
    • The hatching of broiler chicks are part of integrated operations. "The integrated firm thus may own the breeding stock, produce the hatching eggs, hatch the chicks, grow out the broilers on contract, process the broiler meat and distribute the meat to a wholesaler or retail outlet."[107]
    • The first efficient mechanical chicken feeding devices are invented.[108]
  • 1940s-1950s: Poultry Science departments at universities reach peak enrollment. After this, enrollment declines and by the 1970s, many Poultry Science departments have been merged into other departments (such as Animal Science).[109]
  • 1940:
    • Discovery that choline is required to prevent perosis, and biotin, iodine, and glycine are needed in the diets of chicks.[101]
    • The Ohio Agricultural Experiment Station is the first to use a "droppings pit" in a chicken house.[110]
  • 1941: Discovery that potassium, methionine, cystine, and tryptophan are needed by chicks.[101]
  • 1942:
    • Workers in a hatchery try to unionize and the hatchery as well as the local industry association resists their unionization. The National Labor Relations Board ruled that hatchery employees engaged in hatching chicks are agricultural laborers and therefore do not fall under NLRB jurisdiction.[111]
    • Discoveries that magnesium, niacin, and lysine are essential for chick health and biotin is needed by hens.[101]
    • An electric "debeaker" is invented to remove the tip of each chicken's beak to prevent them from injuring or killing other chickens when they peck them.[112] Previous attempts had been made to debeak birds by manually trimming beaks, using a gas torch, and using a soldering iron, but none were satisfactory enough to be adopted by industry. (In the case of manual trimming, it was effective but too time consuming.)
  • 1946:
    • Dr. Fraps at Texas A & Am published information on energy levels of common poultry feed ingredients.[113]
    • Dr. Elvehjem at University of Wisconsin shows that adding antibiotics to chick feed increases growth rates, a discovery that did not become important to the industry for another four years.[113]
  • 1947:
    • Using Fraps' information, Dr. H.M. Scott formulates a new high energy broiler diet.[113]
    • Two different mechanical feeders are patented, both using a chain equipped with paddles to move food along a trough.[114]
  • 1950s:
    • Demand grows for small incubators for classroom use to hatch chicks as an educational activity and for ornamental poultry bantam, and game bird enthusiasts.[115]
    • Larger breeders of egg production stock enter into franchising agreements with commercial hatcheries. The breeders supplied either hatching eggs or breeding stock for producing hatching eggs. The hatcheries would hatch the chicks and distribute them in assigned areas. By the early 1970s, this arrangement produced most of the hens in the egg industry.[116]
    • Commercial amounts of synthetic methionine became available in the early 1950s, allowing for an increase in the use of soybean meal in chicken feed, as soybean meal is low in methionine.[117]
    • Chickens are kept in light and temperature controlled housing.[118]
    • In the late 1950s, a condition called "avian hysteria" is reported in chickens kept in total confinement with a high concentration of chickens. "The afflicted flock's behavior is typified by extreme nervousness."[119]
  • 1950:
    • Although feed pellets and crumbles had been produced previously, they were not used widely because the heating processed destroyed vitamins in the feed. In 1950, an efficient cooling method was invented to allow pellets to be made without destroying vitamins. Pellets were then ground and screened to form crumbles.[120]
    • A mechanical feeder is patented that can be used in caged chicken operations.[121]
  • 1955: Limited artificial light is first used for growing pullets by C.S. Platt at the New Jersey Station.[122]
  • 1956: Linear Programming is used to determine the lowest cost way to produce feed.[123]
  • 1958: A system called "step-down step-up" is developed and becomes popular among many growers to control the onset of egg playing by young pullets with artificial lights.[124]
  • 1960s: Mid-1960s a "high rise" poultry house becomes popular. It uses a 7 to 10 foot deep pit under the chickens to collect manure, and the pit can be cleaned only once ever few years. The house had slat floors or cages.[125]
  • 1960s-1970s: As automatic feeding and watering devices came into use, brooders needed adjustable ones that could be raised in height as the baby chicks grew. "These systems use a variety of heat distribution devices ranging from electric heat cables to finned pipes and perforated plastic tubes. Generally speaking the pullets are started in groups of 20 to 30 and matured in groups one half the size. Some cage systems are designed so that the same unit can serve from day old to maturity (22 weeks) while others employ two stages (0 to 7 weeks and 7 to 22 weeks)."[126]
  • 1971:
  • 1972: Chicken houses have motorized rollers controlled by thermostats to raise and lower plastic sidewall curtains to control the temperature.[128]

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References

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  125. Wilson, W. O. (1974). Housing: Environment Has Been Man’s Concern Ever Since the Hen’s Jungle Days. In John L. Skinner, O. A. Hanke, & J. H. Florea (Eds.), American Poultry History 1823-1973 (pp. 218–247). Madison, WI: American Printing and Publishing, Inc., pp. 227-228.
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  127. Funk, E. M. (1974). Hatcheries: Commercial Hatcheries Provide Ready-made Farmer Egg Machines. In John L. Skinner, O. A. Hanke, & J. H. Florea (Eds.), American Poultry History 1823-1973 (pp. 162–183). Madison, WI: American Printing and Publishing, Inc., pp. 181.
  128. Wilson, W. O. (1974). Housing: Environment Has Been Man’s Concern Ever Since the Hen’s Jungle Days. In John L. Skinner, O. A. Hanke, & J. H. Florea (Eds.), American Poultry History 1823-1973 (pp. 218–247). Madison, WI: American Printing and Publishing, Inc., p. 226.

External Resources

  • Scott, George Ryley. The History of Cockfighting. London: C. Skilton, 1957.

External Articles