In the UK regulations, ‘poultry’ includes chickens, turkeys, ducks, geese, partridges, quail, pheasants, peacocks, pigeons (reared for meat), guinea fowl, ostriches, emus and rheas.
The regulations define certain species, including all poultry species, as food-producing animals. A number of specific legal obligations relate to all food-producing animals, even if kept only as a pet. The UK regulations do not recognise the ‘pet’ status of any farm animal species, including pet poultry. Therefore, pet poultry are subject to legal requirements regarding their husbandry, welfare and veterinary treatment over and above those applying to most other pet species.
The Animal Welfare Act (2006) applies to all kept animals, including pet and food-producing species. Additional regulations concern the welfare of poultry, housing requirements, minimum stocking densities, the sale of eggs, predator control, disposal of waste (e.g. chicken litter), etc.
In addition to the general animal welfare regulations applying to all species, the Department for Environment, Food and Rural Affairs (Defra) has poultry farming welfare regulations (Defra, 2019a). Wales (Natural Resources Wales, n.d.) and Scotland (Food Standards Scotland, n.d.a) have theirs. All poultry owners are required by law to be familiar with Defra's Code of Recommendations for the Welfare of Livestock: Laying Hens (Roberts, 2013; Defra, 2019a).
Other useful guides for assessing and improving poultry welfare are the Farm Animal Welfare Committee's ‘Five Freedoms’ (Defra, n.d.) and the European Welfare Quality assessment protocol for poultry (Welfare Quality®, 2009).
Regulations
Disposal of carcases
It is illegal for owners to bury or incinerate dead poultry or put them in household waste bins (Defra, 2015). Although it is legal for owners to bury pets such as dogs and cats at home, under the EU Animal By-Products Regulations, poultry do not meet the definition of pet animals (Defra, 2019b). Dead poultry that are not to be eaten are ‘fallen stock’ and require disposal by an approved route other than burial or home incineration. They can be disposed of by a veterinary practice or pet crematorium, or by incinerator plants approved under the Animal By-Products Regulations. Pet crematoria are allowed to return to the owners the ashes of poultry.
Feeding scraps
The feeding of catering waste, including owner's home kitchen scraps, to farm animals, has been prohibited under the Animal By-Products Regulations since 2001 (Defra, 2019b). This is to reduce the risk of pathogen transference and includes farm animals kept only as pets. It also includes vegetarian homes — the only exception is homes where all the food is vegan. However, vegetation items from garden or allotment can be fed to laying hens if given directly and not via a kitchen.
GB Poultry Register
It is a legal requirement that all flocks of 50 or more poultry must be registered on the APHA's GB Poultry Register (2019). This applies even if the flocks consist of a mixture of species and if there are 50 or more birds on the premises for only a small part of the year. Smaller flocks can also be registered, but few owners do so, ignoring the advantage of having disease information sent to them quickly (Roberts, 2008).
Record keeping
Since chickens are considered food-producing animals, records must be kept of the animal, location, identification, medication, batch number, dose, date, withdrawal advice.
Regulations relating to notifiable diseases5
The two notifiable pathogens of birds in the UK, avian influenza (AI) and Newcastle disease (ND) (Welsh Government, n.d.; Scottis Government, 2018; Defra, 2019c), have both occurred in the UK poultry industry within the last decade, both have been confirmed in most countries within the EU, and there is a constant risk of either pathogen entering the UK via imported or wild waterfowl and gulls. Suspicion of either disease must be reported to APHA in England, Wales or Scotland (Defra, 2019d).
Salmonellosis, although not notifiable, is a reportable disease, meaning that if it is identified in a laboratory this must be reported to the Animal and Plant Health Agency (APHA) in England (Public Health England, 2017), Public Health Wales (Public Health Wales, n.d.), and Food Standards Scotland (Food Standards Scotland, n.d.).
Zoonoses
The most common zoonoses are campylobacteriosis and salmonellosis. The frequency of human food poisonings associated with poultry Campylobacter and Salmonella species adds particular importance to the responsible use of antibiotics in poultry in order to prevent further development of resistance. Of course, hand hygiene is vital since the whole family often gets involved with chicken keeping.
Other zoonotic organisms include Pasteurella, Erysipelothrix rhusiopathiae, avian TB, Mycobacterium avian complex and Leptospira icterohaemorrhagiae (which causes Weil's disease) carried by rodents; thus vermin and predator control is important.
Vaccination
The major problem with chicken vaccines is that the majority are only effective if young birds are given a primary course. For those vaccines it is not effective to vaccinate adult chickens that have not had the primary course: hybrids are usually vaccinated for example against infectious bronchitis and Marek's disease (Figure 1 and 2), pure breeds rarely because they are hardier. Mixing hybrids and pure breeds carries a slight risk of disease transference but is not generally a problem. Birds can be vaccinated against ND: the vaccine does not completely prevent infection but does reduce disease severity (vaccination has not proved to give particularly good control in outdoor birds). Because the presence of Mycoplasma gallisepticum predisposes birds to infectious bronchitis, it is very important to control the incidence of Mycoplasma spp. in the flock (backyard or pet), which can be helped by keeping ammonia levels down through sufficient ventilation (high ammonia paralyses the cilia, small hairs which act like an escalator in the trachea to remove mucus). With vigilance, Mycoplasma spp. can be kept at a low level, but not eliminated in backyard flocks, thus increasing the welfare of the birds.
Most poultry keepers only vaccinate in general if there is a problem in the immediate area, and this follows the advice given by vaccine manufacturers. Vaccines can mask a disease in a flock: with Marek's disease, some do not vaccinate but cull any birds with signs which eventually leads to much stronger stock because the pathogen is removed from the flock; however, the use of a vaccine can hide the virus and so the whole stock gets pro-gressively more susceptible without any symptoms. If birds are sold without the recipient being told of the vaccination, the birds can pass on the virus to unvaccinated chicks, thereby bringing Marek's disease to a flock which may have been free of it before. Vaccination is desirable in Silkies and Sebrights because they are very susceptible to clinical signs of Marek's disease, and there would be few of these breeds seen at exhibitions if vaccination was not used — it is sensible for the keeper to ask at purchase if they have been vaccinated against Marek's disease or not. Live vaccines have short immunological duration, given by spray or intraocularly and are sometimes used to prime young birds before some inactivated vaccines.
Table 1 shows the most commonly used vaccines in free-range birds. Most vaccines are only available in industrial sizes (1000 or 500) but, if needed, are cheap enough for backyard poultry despite the waste. Most vaccines have zero withdrawal periods (check relevant SPC).
Table 1. Vaccines for poultry
| Disease | Vaccine | Manufacturer | Age and method of administration | Booster interval |
|---|---|---|---|---|
| Infectious bronchitis, Newcastle disease, egg drop syndrome* | Nobilis IBMULTI +ND+EDS | MSD | 16–20 weeks (not less than 4 weeks before lay): 0.5 ml intramuscular (IM) injection | Annual |
| Gallimune 302 ND+IB+EDS* | Boehringer Ingelheim | 16–20 weeks (not less than 4 weeks before lay): 0.5 ml IM injection | Annual | |
| Marek's Disease** | Nobilis Marexine CA 126 (live attenuated frozen in liquid nitrogen) | MSD | Day old–3 weeks: subcutaneous (SC) injection, back of neck | None, but all chicks subsequently hatched on premises must be vaccinated |
| Poulvac MD-Vac (freeze-dried) | Zoetis | Day old–3 weeks: SC injection, back of neck | None, but all chicks subsequently hatched on premises must be vaccinated | |
| Infectious Bursal Disease | Nobilis Gumboro 228E | MSD | 10 days+: via drinking water (one dose) | None |
| Gallivac IBD | Boehringer Ingelheim | 0–14 days by spray, 14–28 days via drinking water (two doses) | None | |
| Poulvac Bursine 2 | Zoetis | 21 and 28 days: via drinking water (two doses) | None | |
| Escherichia coli (type 078) | Poulvac E. coli | Zoetis | Day old: coarse spray | Duration >12 weeks |
| Salmonellosis | Gallivac SE | Boehringer-Ingelheim | Day old, 14 days + 3 weeks before lay: via drinking water (three doses) | None |
| Nobilis Salenvac T | MSD | 12 weeks + 16 weeks: 0.5 ml IM injection, breast | None | |
| AviPro Salmonella Duo (Salmonella enteritidis & Salmonella typhimurium) | Elanco | Day old, 8 weeks + 3 weeks before lay: via drinking water (three doses) | None | |
| Turkey rhinotracheitis | Nobilis TRT inac MSD | MSD | Chickens: 14–20 weeks, previously primed with live vaccine: 0.5 ml IM injection, breastTurkeys: 28 weeks, previously primed with live vaccine: 0.5 ml IM injection, breast | Annual |
| Coccidiosis | Paracox*** | MSD | Dayold up to 9 days: three drops per os | None |
| Infectious laryngotracheitis (ILT) | Poulvac ILT | Zoetis | Eye drop after 4 weeks of age | None |
Marek's vaccine is no longer obtainable in 10 ml bottles but is more useful as the freeze-dried version than that frozen in liquid nitrogen, Pharmsure 01954 262460
***Paracox is available in 100 and 200 dose containers from PHS, Thirsk (01845 577907), and is unreservedly recommended, chicks must be kept on litter, not wire and fed coccidiostat-free chick crumbs
Signs of healthy chickens
Positive signs of health in chickens (Roberts, 2009):
- Dry nostrils
- A red comb (some breeds have naturally dark ones)
- Bright eyes (colour varies with breed), equal pupil size
- Shiny feathers (all present)
- Good weight and musculature for age
- Clean vent feathers with no smell
- Smooth shanks
- Straight toes
- The bird should be alert and active.
Medication
There are restrictions on the number of medicines licensed for use in chickens producing eggs for human consumption, for human protection (Tables 2 and 3). The medicines that are licensed cover the most common problems (Figure 3) and must legally be considered before using the Cascade. Zero withdrawal means eggs may be eaten when treatment is finished. For those who see chickens regularly, it would be most beneficial to the welfare of the hens and their owners to keep licensed products always in stock, thus allowing eggs to be eaten after any stated withdrawal time, rather than being taken out of the food chain for an extended time. There are no licensed injectables.
Table 2. Some examples of licensed medications for use in egg laying chickens; withdrawal times are suggested, always read the current label
| Indication | Medicine | Trade name | MFR | Size | Dose & Tx time (days) | Species | Withdrawal (days) Meat Eggs | |
|---|---|---|---|---|---|---|---|---|
| Bacterial disease (Gram –ve) | Colistin | Colibird (soluble) | CEVA | 250 ml–1 litre | 75 000 IU/kg for 5 days | All poultry | 1 | 0 |
| Bacterial disease (Gr +ve) | Phenoxymethyl-penicillin | Phenoxypen | Dopharma | 250 g | 15 mg/kg for 5 days | Chickens | 2 | 0 |
| Mycoplasmas, Gr +ve, Gr -ve | Tiamulin | Denagard 12.5% Oral Solution | ovartis | 250 ml– 1 litre | 25 mg/kg for 5 days | Chickens | 2 | 0 |
| Mycoplasmas | Erythromycin | Erythrocin Soluble | CEVA | 70 g–1 kg | 5 day | Chickens | 6 | 6 |
| Mycoplasmas, necrotic enteritis | Tylosin | Tylan Soluble* | Elanco | 100 g | 0.5 g/litre for 5 days | Chickens | 1 | 0 |
| Tylosin | Pharmasin granules | Huvephar-ma | 110 g– 1.1 kg | 0.5 g/litre for 5 days | Chickens | 1 | 0 | |
| All helminths (also available pre-mixed in feed) | Flubendazole | Flubenvet (powder) | Elanco | 60 g | 6 g/2 kg of feed for 7 days | All poultry | 7 | 0 |
| Coccidiosis | Amprolium | Coccibal | SP Veterinaria | 100 ml– 1 litre | 20 mg/kg/d for 7 days | Chickens | 0 | 0 |
| (also Paracox vaccine, see Table 1) | Eimeryl | SA. Global Vet Health SL | 100ml-1L | 20 mg/kg/d for 7 days | Chickens | 0 | 0 | |
Table 3. Some examples of products licensed for meat chickens and other poultry
| Indication | Medicine | Trade name | MFR | Size | Dose & Tx time (days) | Species | Withdrawal days meat |
|---|---|---|---|---|---|---|---|
| Bacterial disease | Apramycin | Apralan Soluble Powder | Elanco | 50 g | 20 to 40 mg/kg 5 days | Chickens | 7 |
| Bacterial disease Gr +ve, Gr -ve | Amoxicillin | Octacillin WSP | Eurovet | 100–1000 g | 8 to 16 mg/kg 5 days | Chickens | 1 |
| Amoxicillin | Vetremox | Zoetis | 75–500 g | 20 mg/kg 5 days | ChickensTurkeys | 25 | |
| Amoxicillin | Amoxinsol | Vétoquinol | 75 g | 15 to 20 mg/kg 5 days | ChickensDucksTurkeys | 195 | |
| Bacterial and Mycoplasma disease | Enrofloxacin | Baytril 10% Oral | Bayer | 100 ml –1 litre | 10 mg/kg 3–5 days | ChickensTurkeys | 813 |
| Enrofloxacin | Baytril 10% Oral | Bayer | 100 ml –1 litre | 10 mg/kg 3–5 days | ChickensTurkeys | 813 | |
| Lincomycin/spectinomycin | Linco-Spectin | Kernfarm | 150 g | 10 mg/kg 7 days | Chickens | 5 | |
| Doxycycline | Soludox | Eurovet | 1 kg | 10 mg/kg 3 days20 mg/kg 4 days | ChickensChickens | 312 | |
| Mycoplasma disease | Tylvalosin | Aivlosin 625 mg/gGranules | ECO AnimalHealth | 40g400 g | 25 mg/kg3 days | ChickensPheasantsTurkeys | 222 |
| Tilmicosin | Pulmotil AC | Elanco | 240 ml, 960 ml | 15–20 mg/kg3 days, 10–27 mg/kg 3 days | ChickensTurkeys | 1219 | |
| Tilmicosin | Tilmovet 250 mg/ml Oral Solution | Huvepharma | 960 ml | 15–20 mg/kg3 days, 10–27 mg/kg 3 days | ChickensTurkeys | 1219 |
NONE of the products in this table are licensed for chickens producing eggs for human consumption and most state DO NOT USE (exception — Aivlosin WSG, egg withdrawal time 0 days). IF any of these products are used under the Cascade for these birds, the egg withdrawal time must be at least 7 days, if not longer. Withdrawal times are suggested, always read the current label.
Certain medicines are contraindicated when administered concurrently such as those containing tiamulin fumerate with ionophore coccidiostats. If using tiamulin ensure that a medicated grower ration is not being used at the same time.
Supplements may conflict with each other and are not necessary except in times of stress, e.g. bad weather, exhibiting, after a predator attack.
The Cascade
Under the Cascade regulations, if there is no suitable veterinary medicine authorised in the UK to treat a condition, a veterinary surgeon may, in particular to avoid unacceptable suffering, treat with another product provided the pharmacologically active substances appear in Table 1 of the Annex to Commission Regulation EU (European Union) No 37/2010 (e.g. NSAIDs) (European Commission, 2010). This even applies for birds producing eggs for human consumption where the data sheet or summary of product characteristics (SPC) for that product specifically states not to be used in such birds.
A veterinary surgeon prescribing for, or administering a medicine to, any poultry under the Cascade is required to specify an appropriate withdrawal period to the animal produce. When setting the withdrawal period, a veterinary surgeon must take into account known information about the use of the product on the authorised species when prescribing to another species under the Cascade. Unless the medicine indicates a withdrawal period for the species concerned, this should not be less than: 7 days for eggs, 28 days for meat from poultry and longer withdrawal times are recommended (Roberts, 2008).
In respect of eggs, it is important to emphasise that if the active substance administered does not have a maximum residue limit (MRL) for eggs, the presence of any residues of that substance in eggs (irrespective of the levels) will be illegal. The Cascade requires that a minimum withdrawal period is applied. However, it is the responsibility of the prescribing veterinary surgeon to ensure that the withdrawal period they specify for such products will ensure no residues will be present in the eggs collected for human consumption. They may therefore wish to take a precautionary approach when specifying the withdrawal period in relation to the use of an active substance which has no egg MRL. Where an egg MRL exists, the veterinary surgeon should specify a withdrawal period which will ensure that any residues of the substance in eggs are below the MRL. Since an egg takes 15 days to make, withdrawal times above this are recommended.
It is currently illegal to use medicines with pharmacologically active substances that do not appear in Table 1 of the Annex to EU 37/2010 in poultry or other food producing species (e.g. fipronil), although their inclusion on the list at some later date has not been specifically excluded.
The use of medicines with pharmacologically active substances that appear in Table 2 of the Annex to EU 37/2010 have been specifically banned from ever being used in food producing species and will never appear in Table 1 of the Annex to Commission Regulation EU (European Union) No 37/2010. Such banned substances include: those derived from Aristolochia spp. (and preparations thereof), chloramphenicol, chloroform, chlor-promazine, colchicine, dapsone, dimetridazole, metronidazole, nitrofurans (including furazolidone), ronidazole.
It bears repeating that the Cascade can only be legally considered where there is no suitable veterinary medicine authorised in the UK to treat a specific condition.
Small Animal Exemption Scheme (SAES) medications should not be used in food-producing chickens. There are numerous empirical reports of resistance by red mite and northern fowl mite to ivermectin (an SAES medication) due to overuse for any external parasite.
The proportion of backyard chicken keepers willing to pay for laboratory culture or post mortem, in the author's experience, is small but needs to be encouraged for proper diagnosis.
Prevention of disease
A number of things can be put in place to help prevent disease (Roberts, 2018):
- Good ventilation (at the top and on two sides) in their living quarters to reduce ammonia levels and thus enhance respiratory function.
- As hens do not have teeth, food is ground up in the gizzard (always provide mixed poultry grit ad lib), old long grass should be avoided as this can impact the crop and gizzard and be potentially fatal. Feed must be stored dry and vermin-proof and used before the date on the label to avoid degradation of the feed quality.
- Avoid muddy areas by placing a mesh grid over the grass before adding hens, which allows grazing but not root destruction. A dust bath helps prevent parasite infestation.
- Monthly dunking of legs in surgical spirit prevents scaly leg infestation (Roberts, 2009). Generous and continuous use of diatomaceous earth (DM: fossilized algae which slowly desiccates the chitin, beware diluted DM in petshops) in the hut prevents red mite numbers escalating. It should not be fed to hens but can be used topically if northern fowl mites are found.
- Problems occur if hens are kept on the same small area of ground (Roberts, 2018), which then becomes ‘sour’ and harbours harmful parasites, helminths and other pathogens. It is important to worm them with flubendazole (the only licensed wormer) 2–3 times a year (Roberts, 2018): faecal worm egg counts may provide false negatives if the helminths are not adult. Detritus under bird tables is a strong risk of disease transference, keep hens away from this.
- Clean, fresh and flowing water is vital for poultry health as they dehydrate easily and need to maintain egg production. Biofilm should be scrubbed away from drinkers and a safe disinfectant such as Virkon (Antec International) or F10 Health and Hygiene, South Africa) used (phenolic products are toxic to birds). Unpasteurised cider vinegar (10 ml:500 ml, plastic drinker only to avoid zinc toxicity) in the drinker 1 week a month helps reduce bacteria and parasites in the drinker (Roberts, 2009) and in the gut of the hens and is said to support the immune system. A higher dose of 50 ml:500 ml may be useful in times of stress or disease.
The Animal Welfare Foundation (AWF, n.d.) Poster is a useful summary.
Conclusion
There is no reason why the pet chicken cannot be diagnosed and treated to a similar quality level as cats and dogs.
KEY POINTS
- Legislation must be known and obeyed.
- The welfare of animals is top priority.
- Food-producing species have different regulations to meat species.
- Prevention of disease-encouraging husbandry is important.
- UK countries may have different laws.