Introduction to backyard poultry (Proceedings)


Raising backyard poultry can be rewarding not only for the production of consumable eggs and meat, but also for companionship and personal enjoyment.

Raising backyard poultry can be rewarding not only for the production of consumable eggs and meat, but also for companionship and personal enjoyment. Providing veterinary care for these clients and their birds can be equally rewarding as long as the veterinarian is armed with a solid understanding of federal, state, and local laws and regulations that affect backyard poultry and with a working knowledge of common diseases and treatments for these species.

Definition of “poultry”

The term “poultry” should be considered as referring to any avian species that has the potential for its meat, eggs, or other parts (eg. offal, feathers, manure) directly or indirectly entering the human food chain, regardless of the actual use of individual birds of each species. The Code of Federal Regulations (CFR) defines “major” animal species as dogs, cats, horse, cattle, swine, chickens, and turkeys. All others are considered “minor” animal species, such as ducks, geese, game birds, pigeons, etc.


It is widely recognized that backyard poultry are growing in popularity. With a national trend towards locally produced foods and organic foods, this fact is not surprising. Raising poultry can also be personally enriching and educational. According to the United States Department of Agriculture (USDA) National Animal Health Monitoring System (NAHMS) Poultry 2010 survey “Urban Chicken Ownership in Four U.S. Cities,” which surveyed urban chicken ownership in Denver, Los Angeles, Miami, and New York City, 0.8% of all households in these cities owned chickens and 4.3% of single-family homes on one acre or more. Nearly 4% of households that did not have chickens at the time of the survey were planning on owning chickens within the next 5 years. With the recent steady decline in parrot ownership, poultry veterinary patients will undoubtedly become more common in the upcoming years.


Most poultry species fall within a few avian orders, including Galliformes (eg. chickens, turkeys, quail, pheasants, grouse, guinea fowl), Anseriformes (ducks, geese, swans), and Columbiformes (pigeons and doves). Ratites such as ostriches and emus should also be considered as poultry species. Storey's Illustrated Guide to Poultry Breeds 2007 is an excellent resource for learning about different poultry breeds.

The domestic chicken, Gallus domesticus, is widely believed to be descended from the red jungle fowl from geographical areas such as southern China and Indonesia, although there may have been genetic crossing with other avian species such as the grey and Sri Lankan jungle fowl. Today there are hundreds of breeds of chickens around the world, categorized by class (geographical area (eg. American) or, for bantams, by physical traits such as Single Comb), variety (based on physical characteristics such as color and comb type), and strain. Chickens are often classified as standard breeds (usually larger and more popular or commercially raised for eggs or meat such as barred rocks and Rhode Island reds), bantam breeds (smaller breeds such as silkies), and heritage breeds. Commercial breeds include broilers and layers. See the American Poultry Association Standards of Perfection ( for further information about chicken breeds.

Regulation and biosecurity

Ownership laws and regulations

Although the commercial poultry industry is tightly regulated by federal and state laws, backyard poultry are largely exempt. Regulation of backyard poultry flocks is typically limited to local ordinances, and some municipalities have no regulations at all. Local ordinances can regulate ownership by requiring permits or licenses, or by dictating care and husbandry such as defining limits on property size and available coop space per bird and through nuisance clauses for noise, odor, and cleanliness.

Biosecurity and quarantine

Remember that “an ounce of prevention is worth a pound of cure.” Biosecurity is the cheapest and most effective means for limiting or preventing the introduction and spread of infectious agents to and within a backyard flock. There are three major principles to biosecurity – management of access (eg. the “closed” flock concept, isolation or confinement), animal health management (eg. good record keeping, veterinary care), and operational management (eg. cleaning and disinfection, pest control).

Backyard poultry inherently pose a risk to the commercial poultry industry for the spread of highly pathogenic diseases such as exotic Newcastle disease (END) and highly pathogenic avian influenza (HPAI). The backyard poultry veterinarian serves a crucial role in the early detection and notification (reporting) of potentially serious contagious diseases.


Care and husbandry

This section on backyard poultry care and housing will be limited to the domestic chicken for the purposes of this discussion.

Housing (coop and pen)

The backyard chicken coop can range from simple to highly elaborate, but the basic requirements are the same – the coop must be easy to clean, secure from predators, allow adequate space per bird, and allow adequate ventilation. The coop should protect the birds from weather extremes.

  • Space – Adult chickens need a minimum space of about 2 to 3.5 ft2 (0.19 to 0.33 m2) per bird. Chicks up to 2 weeks of age need at least 10 square inches, but by 4 to 8 weeks of age then need at least 1 ft2 (0.09 m2) per bird.

  • Bedding and flooring – The coop floor can consist of concrete, wire, wooden slats, or dirt. Pine shavings, straw, and well-drained soil are common beddings for chickens, although pine shavings are most often used for chicks. Some coops are mobile, allowing movement around a yard to cleaner areas with fresh forages.

  • Nest boxes – Nest boxes should be provided for layers, at one nest box for every 4 to 5 hens. Boxes should measure at about 12” x 14” (30 x 36 cm) for most breeds with about 6” (15 cm) of bedding and should be raised off the floor. Egg production begins at about 16 to 24 weeks of age and peaks at 32 to 34 weeks for many layer breeds. Production may slow or stop during shorter daylight months.

  • Perches – Each bird should have at least 9 to 10” (23 to 25 cm) of perching space with 14” (36 cm) between perches,

  • Temperature – The adult chicken is most comfortable and efficient at egg production between 70 and 75°F (21 to 24°C). Adult chickens may die of heat stress at temperatures over 95°F (35°C). Chicks initially should be kept at 95°F (35°C) with weekly decreases of 5°F (3°C) until room temperature is achieved.

  • Security – Measures that can be taken to protect chickens from predators in the pen and coop include burying wire 6” (15 cm) deep or with a 12” (30 cm) bend, by double wiring the pen and providing a wire or solid roof, and by ensuring that the walls of the coop are predator proof. Free ranged chickens are at greater risk of predation, but a fenced in yard can provide some protection.


Selecting a diet for the backyard chicken will depend upon the age, species, and use of the birds. Commercially formulated diets are widely available for all poultry species, including galliformes, anseriformes, columbiformes, and ratites, and for a variety of life stages. Diets should be based on formulated feeds and supplemented with additional foods for enrichment such as vegetables, forages, fruits, and scratch feeds. Oyster shell grit should be provided to layers. Free ranging allows birds to forage for foliage and insects and provides enrichment. Supplements should be limited, particularly in rapidly growing birds, to reduce the risks of angular limb growth deformities. Obesity is common in adult birds and is often attributed to excessive energy foods and reduced activity. Clean, fresh water should always be provided in easily accessible waterers.

  • Chicks –
  • 0 to 6 weeks of age – Chick starter ration (18 to 20% protein). Chick starter rations should contain a coccidiostat.

  • 6 to 14 weeks of age – Chick grower ration (16 to 18% protein)

  • 14 to 20 weeks of age – Developer ration (14 to 16% protein)

  • 20 to 24 weeks of age – Layer ration (16 to 18% protein)

Veterinary care

Although most standards of avian veterinary care apply to backyard poultry, the practitioner must also be aware of certain legal issues such as federal laws regulating drug use in food-producing species. Additionally, some veterinary duties may require Category II USDA accreditation. Professional organizations such as the USDA and state departments of agriculture, university poultry extension offices, and board-certified poultry or companion avian veterinarians are readily available for consultation and referral and often publish or otherwise provide free literature and other resources.


Solid history taking and physical examination skills are very important in working with backyard poultry presented for veterinary care. The practitioner should always be aware of the client's goals, expectations, and limitations to care. In addition to the standard anamnesis, information regarding the source of the bird, duration of ownership, vaccination status (eg. Marek's disease), exposure to other birds, exposure to wildlife and feral birds, use of the bird (eg. companion, layer, meat producer), and use of the eggs and meat (if applicable) should be obtained.

Physical examination

The physical examination is straightforward. Chickens are generally very easy to examine but they do stress quickly and can become overheated. Some birds are calmer when the head is covered. A digital cloacal (“rectal”) exam is a useful method to help assess the gastrointestinal and reproductive tracts. The color of the comb and wattles can suggest anemia or cyanosis.



Diagnostics routinely run for backyard poultry include fecal exams (both wet mount and flotation, occasionally sedimentation), bloodwork (hematology and biochemistry), and survey radiographs. Birds can be screened for infectious diseases if indicated, but clients should be advised in advance if any of these diseases is reportable. Necropsies are commonly performed to assess flock health for both commercial and backyard settings. Most states offer necropsy services to veterinarians and clients through state run veterinary diagnostic laboratories.

Drug regulations

Drug use in food producing animal species is heavily regulated by federal law, regardless of the use of individual animals. There are very few drugs that are labeled for use in poultry. The Animal Medicinal Drug Use Clarification Act (AMDUCA) of 1994 made extra label drug use (ELDU) legal in veterinary medicine with a valid veterinarian-client-patient relationship (VCPR). ELDU is allowed only for FDA approved drugs in food producing animals, and is not permitted for eggs or meat intended to be sold or given away. ELDU in feed is strictly prohibited. There are very specific requirements for record keeping and prescription labeling for ELDU in food producing animals. For example, medical records must be kept for at least 2 years. Withdrawal times for meat and eggs must be documented in the medical records and placed on the prescription label.

Restricted and prohibited drugs

Veterinarians treating backyard poultry must be aware of federally restricted and prohibited drugs. For example, fluoroquinolone antibiotics such as enrofloxacin and nitroimidazole antibiotics such as metronidazole are prohibited from use in food producing animal species such as poultry. A list of restricted and prohibited drugs is available on the Food Animal Residue Avoidance Databank (FARAD) website – ( If a withdrawal time for meat or eggs is not known for a particular drug, FARAD should be contacted. Expect a 1 to 3 day turnaround time for the information. Communication with FARAD and the provided withdrawal times, if known, must be documented in the medical record.

Some approved drugs in poultry

While there are a few drugs that are approved for use in poultry, their use may be restricted by the age or intended use of the bird. For example, the antibiotics tylosin and sulfadimethoxine are approved for use in broilers and replacement chickens. The dewormer piperazine is approved for use in broilers and replacement chickens, and amprolium is approved for use in all chickens. Regardless of the information here or in published formularies, always request information from FARAD to ensure the current approval status of any drug intended for use in food producing animal species such as poultry.

Suggested reading

Ekarius C. Storey's Illustrated Guide to Poultry Breeds, Storey Publishing, North Adams, MA, 2007.

Garber L, Hill G, Rodriguez J, et al. Non-commercial poultry industries: Surveys of backyard and gamefowl breeder flocks in the United States. Prev Vet Med 2007;80(2):120-128.

Goetting V, Lee KA, Tell LA. Pharmacokinetics of veterinary drugs in laying hens and residues in eggs: A review of the literature. J Vet Pharmacol Therap 2011;34(6):521–556.

Greenacre CB, Morishita TY (eds). Backyard Poultry Medicine and Surgery: A Guide for Veterinary Practitioners. Wiley Blackwell, Ames, IA, 2015.

Greenacre CB. Backyard poultry: A crash course so you are prepared. Proc Assoc Avian Vet 2013:3–12.

Grunkemeyer VL. Zoonoses, public health, and the backyard poultry flock. Vet Clin No Amer Exotic Anim Pract 2011;14(3):477–490.

Kelly LM, Alworth LC. Techniques for collecting blood from the domestic chicken. Lab Anim 42(10):359–361.

Pollock SL, Stephen C, Skuridina N, et al. Raising chickens in city backyards: The public health role. J Commun Health 2012;37(3):734–742.

USDA. Poultry 2010. Urban Chicken Ownership in Four U.S. Cities. USDA–APHIS–VS, CEAH. Fort Collins, CO, 2012.

Whitehead ML, Roberts V. Backyard poultry: Legislation, zoonoses and disease prevention. J Small Anim Pract 2014;55(10):487–496.

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