A PRACTICAL GUIDE TO SALMONELLA INFECTIONS …...A brief introduction to Salmonella and its controls is offered in the first 2 chapters with the rest of the booklet (beginning on page

A PRACTICAL GUIDE TO SALMONELLA

INFECTIONS IN COMMERCIAL FREE

RANGE EGG LAYING HENS

A BRITISH FREE RANGE EGG PRODUCERS ASSOCIATION SUSTAINABILITY FUND REPORT

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A BRITISH FREE RANGE EGG PRODUCERS ASSOCIATION SUSTAINABILITY SCHEME REPORT 003

Contents005 PREFACE

006 WHAT IS SALMONELLA?

008 HOW DOES THE INDUSTRY CONTROL SALMONELLA?

010 WHAT DO MY SALMONELLA RESULTS MEAN? 011 Not Detected 011 Suspect Result 012 Positive Result 014 MY FLOCK TESTED POSITIVE FOR SE OR ST, WHAT HAPPENS NEXT? 015 Where can I send my eggs? 016 Do I need to mark eggs from this house? 016 What about the other houses on site? 016 Should I contest the result? 016 How to contain the problem? 016 Should I keep the flock housed? 017 Do I keep the flock going? 017 How long do I need to clean and disinfect after a positive Salmonella? 017 Which areas need cleaning? 018 Do I need any specialist cleaning chemicals or equipment? 018 When will I regain my status? 019 When do I repopulate? 019 What about my replacement pullets? 019 What about the range? 020 Who else will visit?

021 DEPOPULATION

022 MUCK REMOVAL

024 CLEANING

026 DISINFECTION

028 POST CLEANING SWABBING

030 OTHER AREAS FOR CONSIDERATION

Regular monitoring alongside vaccination, improvements in husbandry and biosecurity have made UK eggs safe and generated enormous consumer confidence.

Preface

This booklet was written by two veterinary surgeons with first-hand experience dealing with laying flocks which have become infected with controlled types of Salmonella. The booklet describes the very involved process of dealing with this difficult situation, with a step by step guide to many of the issues involved with the clean-up operation and subsequent demonstration of disease free status. A brief introduction to Salmonella and its controls is offered in the first 2 chapters with the rest of the booklet (beginning on page 10) dedicated to managing the situation, and overcoming the infection.

With thanks to Ian Lowery, Crowshall Veterinary Services and Ian Jones, Hafren Veterinary Group for their work in bringing this guide together and sharing their practical experiences dealing with real-life cases of Salmonella in free range laying flocks

005A BRITISH FREE RANGE EGG PRODUCERS ASSOCIATION SUSTAINABILITY SCHEME REPORT

WHAT IS SALMONELLA?

Salmonella is a large family of bacteria which can infect a wide range of animals including humans, farm animals, pets and birds.

Salmonella is a large group of bacteria which can infect a wide range of animals including

humans, farm animals, pets and birds. Not all salmonellas cause disease in all animals.

Some salmonellas can infect a particular animal without causing any ill health.


The Salmonella types of particular importance to the laying industry are those which infect chickens without mainly causing disease in infected flocks but which can be passed on to humans leading to diarrhoea,vomiting or more serious illness. This booklet will focus on 2 particular types, Salmonella Enteritidis (SE) and Salmonella Typhimurium (ST). These bacteria can cause severe disease if they infect people (and usually show no signs in adult hens) and are controlled by assurance schemes such as BEIC and Laid in Britain codes and also by DEFRA and DAERA. The National Control Program which routinely monitors adult flocks for Salmonella every 15 weeks during lay began in 2008. Regular monitoring alongside vaccination, improvements in husbandry and biosecurity have made UK eggs safe and generated enormous consumer confidence. The wide scale production of Salmonella free eggs, and the reduction in human salmonella cases has significantly contributed to an increase in egg consumption. BEIC, Lion Code and similar assurance schemes enforce strict rules of membership in order to maintain these standards and keep the risk of Salmonella infection very low. These trade organisations operate on

behalf of the wider industry to police these standards to maintain market confidence. In the rare event of Salmonella (SE or ST) being detected in a flock the eggs will immediately lose their accreditation scheme status, until such time as assurance of freedom from infection can be demonstrated. Regaining membership of your assurance scheme will be difficult and expensive and will require significant collaboration between yourself, your veterinary surgeon and your support team in order that you can demonstrate disease freedom through extensive sampling. This strict approach to Salmonella is absolutely necessary to maintain consumer confidence. Other salmonellas which may infect and cause disease in chickens are not the subject of this booklet. Rather, this booklet explores the impact which SE and ST infection might have on laying flocks and offers practical advice on how to manage flocks and buildings in the rare event that Salmonella is detected on farm.

HOW DOES THE INDUSTRY CONTROL

SALMONELLA?

Once housed birds must be sampled by submitting 2 pairs of bootswabs (ie 4 individual bootswabs) per

house every 15 weeks (105 days) starting at any time between 22 and 26 weeks of age.

Regular testing of breeding, rearing and laying flocks for Salmonella ensures that chicks or

pullets arrive on your farm free of infection and can be demonstrated to remain free of

infection throughout their laying lives.


Assurance scheme reared point of lay pullets will have undergone a program of Salmonella testing starting with the parent breeder flocks and covering the hatchery and also on the rearing farms. Birds have to receive a recognised, correctly administered program of Salmonella vaccinations during the rearing period. These vaccines are only administered with a view to protecting human health, they do not afford any specific health benefits to your chickens. As with all vaccines, Salmonella vaccines protect against infection with SE and ST however they have their limitations and can be overwhelmed if flocks are exposed to significant disease challenge. Laying houses receiving pullets must have undergone a strict program of cleaning and disinfection followed by pre-housing testing (swabs) for Salmonella. This sampling is conducted by the farmer prior to pullet delivery. Once housed birds must be sampled by submitting 2 pairs of bootswabs (ie 4 individual bootswabs) per house every 15 weeks (105 days) starting at any time between 22 and 26 weeks of age. It is important that producers adhere to these timings or they will face significant fines and could lose accredited status. Swabs are tested at approved laboratories where they are cultured for Salmonella. Given the intensive Salmonella testing throughout their lives it is vital that the

infection is not inadvertently introduced to the flock. There are a number of potential sources of Salmonella infection. The following list includes key sources of Salmonella which you may wish to discuss with your vet: • Vermin (rats and mice) • Humans either infected with Salmonella or walking the bacteria into the house on clothing, footwear, equipment etc • Dogs (or other pets). These animals can carry Salmonella and should not be permitted into the house • Other livestock (particularly pigs, but also cattle and horses) • Wildlife, especially wild birds and vermin, particularly if they can gain access to the house or range • Food and water We do not intend this booklet to be a guide to Salmonella prevention or management but felt that given the importance of biosecurity it should be acknowledged in this chapter. Despite a low occurrence of infection and routine vaccination, biosecurity remains a hugely important method of maintaining salmonella freedom. It is unwise to depend solely on vaccinal protection without also working to exclude infection from your farm. The cost of infection can be catastrophic to egg producing businesses and every effort must prevent introduction of infection at all times.

WHAT DO MY SALMONELLA RESULTS MEAN?

There are a number of potential sources of Salmonella infection... vermin being one of them.

Whilst adult chickens do not suffer disease with SE and ST the bacteria likes to live in chickens intestines and multiply quickly leading to high levels of Salmonella in the house which are easily picked up by bootswabs. Testing laboratories are very good at finding even very low levels of Salmonella from bootswabs. Assuming the samples have been taken properly a “Not Detected” result means that no Salmonella organisms have been found in your sample. You should be confident your flocks are clean and continue to monitor every 15 weeks.

Not Detected


The testing process takes a number of days and during this time bacteria may be found which require additional work to confirm or discount the presence of Salmonella. At this stage your lab may issue an interim suspect report or may ring you to advise that further testing is required. Remember there are many bacteria which may mimic Salmonella during the early stages of testing and also many salmonellas which are not SE and ST. In the event of a suspect result do not panic but immediately review biosecurity.

Suspect Result

012

Positive result

As mentioned above there are many types of Salmonella however it is only SE and ST which are of significant consequence to commercial egg producers. Alongside these “natural” (field) strains of Salmonella live vaccines administered in rear can also be detected in some circumstances. All salmonellas can be classified in a laboratory and are grouped. SE is a Group D Salmonella and ST is a Group B Salmonella and it is these which will affect your eggs’ status. A summary of potential results is shown opposite.

Not Detected

Suspect result

Positive Group B or D confirmed

vaccine strain

(NB it is uncommon to isolate a Group B vaccine strain)

Positive Not Group B or D

Positive Group B or D confirmed

not ST or SE

Confirmed positive SE or ST


Your vet and testing laboratory ought to be able to guide you through the events surrounding a positive result.

Action Biosecurity

Inform BEIC or

equivalent and

packer?

Will APHA

visit?

Nil Continue No No

Await final report. You may wish to discuss with your vet Enhance No No

Nil Continue No No

You may wish to discuss potential source with your vet Enhance No Maybe

You may wish to discuss potential source with your vet Enhance No Maybe

Inform BEIC or similar, inform egg packer discuss with your vet

Isolate flock and farm from any other at risk poultry and livestock

Yes Yes

MY FLOCK TESTED POSITIVE FOR SE OR ST,

WHAT HAPPENS NEXT?

It is vital that biosecurity is maintained to prevent accidental introduction of salmonella

You are obliged to inform your egg packer and assurance scheme as soon as a confirmed

Salmonella Enteritidis or Salmonella Typhimurium result is received. Usually this result

would have been confirmed by an APHA laboratory by this stage.


Historically mechanisms were available to re-test or contest a positive result however in the authors’ experience, unless there is a genuine suspicion of a false result or cross-contamination this process is costly, time consuming and is likely to serve only to delay the inevitable. You may wish to quickly submit voluntary samples to your usual lab confirm the result, however it is important that there is no delay in beginning to plan for potential depletion and the subsequent deep clean. As soon as you inform your assurance scheme and packer you will no longer be quality assured and you will not be able to sell grade A shell eggs from the affected house either to your packer, or on the open market. At

this stage it would be strongly recommended to engage with your vet to discuss the situation and short-term and long-term management of the emerging problem. Your most immediate concern at this stage will be what to do with the eggs which will continue to be produced by your flock every day. Other aspects requiring consideration include whether you will cull the flock, how you will eliminate infection from the flock/house and how or when you will restock the house or site. The following list of points is not exhaustive, butmay be used to guide discussions with your packer and vet, indeed, if you aim to regain assurance status you will be required to demonstrate a written management plan from your vet:

Agenda Item Considerations

Where can I send my eggs?

The right answer will depend on the market price for pasteurised egg. Domestic demand for pasteurised egg varies greatly and as such the willingness of UK breakers to take eggs

of known Salmonella positive status will also vary. You may find that eggs need to be exported as Grade B for heat treatment. Your egg packer should be best placed to help navigate these

difficult economic decisions.

016


Do I need to mark eggs from this house?

Eggs from the affected house will need to be marked as Grade B as instructed

What about other houses on the site?

Only the house where the positive result derived from is considered positive HOWEVER clear traceability and separation of eggs from other houses must be demonstrated. You should

raise this with your packer to ensure that eggs from other houses are packed and kept entirely separately.

Should I contest the result?

In the authors’ experience it is highly unlikely that the result would be wrong. You may wish to discuss options with regards

to follow-up testing with your vet.

How to I contain the problem?

All focus should be on preventing the spread of Salmonella to other poultry houses, livestock, people, pets or rodents. Rodent

control should be enhanced and the highest levels of biosecurity introduced immediately. Your vet will be able to

guide you on this.

Should I keep the flock housed?

In the authors’ opinions housing infected flocks will help minimise further contamination of the range, wildlife and

vermin and will help with the subsequent clean-up operation. Consideration of the economic impact of this will be necessary.



Do I keep the flock going?

Decision to cull out the flock will depend on Grade B egg prices and also the risks associated with keeping an infected flock on the site. The age of the flock and whether replacement pullets

are already booked will affect this decision. As most salmonellas are detected later in lay it is likely replacement birds are already in rear. DO NOT UNDERESTIMATE HOW LONG IT WILL TAKE TO CLEAN THE SITE TO ASSURANCE SCHEME STANDARDS AFTER

DEPLETION. Build a timeline with your vet which focuses on ensuring the next flock can remain free.

How long do I need to clean and disinfect

after a positive Salmonella?

Salmonella (particularly SE) is difficult to eradicate and will penetrate into any nook or cranny where dust can settle. It

survives very well in dust. You will need to completely dismantle all equipment, set up washing and dipping stations and fully wash all areas of the house and surrounds effecting repairs etc where necessary. This will take AT LEAST twice as

long as your normal turn around program.

Which areas need cleaning?

In short everything needs a deep clean. This is covered in more detail in the next chapter

018


Do I need any specialist cleaning chemicals or

equipment?

Coverage is the most important thing and this will be enhanced by effectively dismantling all laying equipment. Prior to disinfection the site must be absolutely spotlessly clean. Orchard sprayers, fogging equipment, cherry pickers and

professional cleaning gangs are all recommended to maximise quality of clean and contact with disinfectants.

Do not forget areas such as control rooms, egg rooms, feed bins, augers, equipment like brooms etc. DEFRA Approved

disinfectants at General Orders rates or higher are necessary. Creosols and Aldehydes are usually recommended. Ask your vet

for advice on the most appropriate products for your site.

When will I regain my status?

Your site will undergo very thorough swabbing for Salmonella. This is conducted by a representative of your assurance scheme (eg Lion code). Any area of the house is liable to be swabbed. ALL swabs (usually 100+ per house are taken) will need to be

negative to demonstrate freedom. In the Authors’ experiences some residual areas of Salmonella are likely to be discovered at

this very intensive testing.

If positive swabs are found further disinfection followed by additional swabbing (this time at the owners expense)

will be required.

Time to conduct additional cleaning, disinfection and testing must be factored in when deciding when to deplete the existing

flock. The exacting standards of cleanliness required at this stage can be very frustrating however it is vital that assurance schemes maintain these standards as it is their role to protect

the public for the good of the industry rather than to help individual producers to restart egg production.



When do I repopulate?

The ONLY time you can effectively clean and disinfect a house is when it is empty. DO NOT Repopulate until you, your vet, your

packer and assurance scheme are all satisfied that the site is clean. If your pullets are already in rear you may not have time to conduct the quality of clean required. You must liaise with

your pullet rearer as soon as you have developed an initial timeline of activities with your vet.

What about my replacement pullets?

BEIC require that replacement pullets destined for a previously SE or ST positive premises have their Salmonella vaccine

administration audited. This needs to be arranged via your vet and pullet rearer. It is also strongly advise that live vaccination is

enhanced. You will also have to administer a competitive exclusion product (ask your vet) administered on the laying site.

What about the range?

Usually it would be advisable to keep birds housed from time of Salmonella being detected to time of depletion. Catching

should be managed to minimise contamination of areas outside the house.

Wet areas must be drained, muck around the house scraped

away and disposed of, and grass cut short to maximise UV contact. New stone can be placed around the house and

appropriate disinfection of outside areas should be considered.

Check for rat holes on the range and bait appropriately.

020

Having discussed the above points with the relevant advisors it ought to be possible to make informed decisions on storage and sale of eggs, timing of depletion, management of cleaning program and date of pullet placement. You need to write out a time line and regularly review progress. Do not underestimate how long it will take to demonstrate to assurance scheme satisfaction that your site is clean.


Who else will visit?

APHA will offer a visit to better understand the outbreak. At least one visit will be conducted on behalf of your assurance

scheme (eg Lion code). Usually there is opportunity to negotiate the timing of these visits to fit with your proposed

cleaning and disinfection time line.

Your packer should conduct an audit. You may also have a visit from your pullet rearer’s vet.

Depopulation

Careful planning will be required as there are limited options for processing birds known to be infected with Salmonella. These birds cannot enter the food chain as fresh meat and require further processing. It is important that you complete your Food Chain Information correctly and it is advisable that the situation is discussed with your usual spent hen plant who may wish to process the birds last in the day or may seek to find alternative processors. The additional difficulties around killing infected flocks will cause a delay which can further reduce time available for cleaning and disinfection. If in doubt take the soonest date available for processing. Biosecurity must be considered around catching activities. Normal personal hygiene ought to protect catching staff from becoming

infected although it is advised that gangs are alerted as to the risk and additional alcohol hand gel and wash facilities are provided. Catching should be organised to prevent people or vehicles taking the infection out of the house during depopulation. The catching company need to be aware that staff, equipment and vehicles must be fully cleaned and disinfected prior to going to any other sites. A bird free period of 48 hours is advised, along with full change of clothes and disinfection of footwear & vehicles. Once the house is depleted the whole building should be closed and made bird and rodent proof.


For multi-tier systems where muck is being removed regularly whilst the birds are still housed this matter needs urgent consideration, as soon as the positive result is received. Muck from infected houses will contain significant levels of Salmonella and must be handled carefully to prevent spread of infection to other birds, wildlife or rodents. Handling of muck whether from infected birds in a multi-tier unit or empty houses should follow the same set of procedures. All muck needs to be removed to a safe site a significant distance from poultry units and ranges. Muck must be sheeted in transport to prevent contamination of yards or roadways. Muck should not be sold to other farmers without appropriate discussions.

It is advised that muck is stacked and then sheeted to allow it to compost. After 6 weeks the muck may be spread on ground providing there is no direct contact with livestock for 3 weeks. Run-off should be managed to prevent contamination of ground or water courses. It is advisable that you liaise with your local APHA office to get further advice on this subject. The muck is subject to animal biproduct regulations. Muck should be carefully removed from the house to minimise contamination of the areas immediately around the house. If these areas become contaminated there is a significant risk that bacteria may get

Muck Removal

022

walked into the house either after it is cleaned or after the new pullets are delivered. In an ideal world hard standing outside the house can be kept cleaned and disinfected however rubble or mud will be more difficult to effectively manage. A physical demarcation between “clean” outside and “potentially infected” outside is recommended, so that dirty areas can be cordoned off and cleaned to prevent contamination of the “clean” area


Different houses will require a different approach but in all cases equipment needs to be dismantled as far as possible and subjected to detailed and thorough cleaning using an appropriate detergent. In some cases this may occur within the poultry house and in other cases a washing station with power washer and dip-tank can be set up on hard standing outside. The choice of cleaning area depends on the risk of taking bacteria outside vs the risk of re-contaminating clean equipment inside. The outcome of cleaning should be that a visual inspection of the house, equipment, ventilation system, feeding system, drinking system, nest boxes, egg belts, lights, vents, muck belts etc shows that all are spotlessly clean. There cannot be any organic material or splash marks.

Washing should occur from top to bottom so that any displaced dust does not re-contaminate areas which have already been washed. High pressure washers ideally with in-line dosing to ensure correct concentration of detergent and foaming lances should be used. Hot washing will further activate cleaning chemicals. Grease can protect bacteria from disinfection and so use of pressure, heat and detergents is a vital step in effective cleaning. Cracks in flooring or walls must be cleaned and repaired. Any hollow piping used to support drinkers or used as perches needs to be washed out and then sealed. Expanding foam and sealants should be used to physically separate the inside of the house from the internal fabric of the building. Any older damaged parts (eg nest box curtains or mats) would be better discarded and replaced.

Cleaning

024

Electrical panels also require cleaning. These need more careful handling using brushes and hand cleaning rather than pressure washing. Feed bins will also require cleaning. Any residual feed will need to be removed and any dust or material in the feed bins knocked down. Feed bins should then be fumigated. Waste water should be collected and suitably disposed of to prevent dispersal of the infection. THE WASHING PHASE IS VITALLY IMPORTANT TO CLEANING YOUR HOUSE. Disinfection of poorly cleaned houses is a waste of time and money. Conduct a detailed visual audit before proceeding with disinfection. Wiping white babywipes over surfaces wil reveal any residual dirt. If in doubt wash again or ask for a second opinion.

As with the mucking out procedure it is important that cleaning does not inadvertently contaminate the outside area. Likewise as soon as cleaning begins a barrier should be implemented so that no Salmonella can get into the house from outside. Indoor boots and overalls should be supplied and a clean area offered for operatives to get changed. This may simply be slats raised off the ground on bricks and kept clean with a regular application of glutaraldehyde disinfectant.


The house and equipment must be completely dry prior to disinfection. It is strongly advised that at least 2 disinfectant passes are used, spraying in opposite directions. The class and method of administration may vary depending on circumstance and weather conditions. It is essential that every single part of the house gains contact with disinfectants. Disinfectants must be mixed to ensure they are at the correct concentration and sufficient water is used to ensure saturation coverage and sufficient contact time. As with cleaning, cherry pickers, orchard sprayers and foggers are useful, however primary disinfection with high pressure sprayers is of paramount importance.

It is useful to liaise with your vet, APHA and DEFRA on the most up to date advice on choice of chemical. The authors have experience using Creosols, Glutaraldehydes and Formaldehyde. Formaldehyde spraying or fogging appears to be particularly useful. Advice must be sought to ensure combinations of disinfectants do not inhibit each other. It is advisable to conduct a preliminary disinfection prior to reassembly followed by a secondary disinfection after reassembly of equipment. If the house is to be fogged with formaldehyde this can be done after the second disinfection. As with the washing process it is vital that biosecurity is maintained to prevent accidental introduction of salmonella into the house.

Disinfection

026

Testing of the house should only be conducted after secondary (or tertiary) disinfection however please note that sampling will only be conducted once the disinfectants have dried and there is no odour or evident residue. Time post disinfection must be factored into your timeline when planning these post cleaning swabs. Please remember that all cleaning and disinfection procedures should also be applied to service areas and egg rooms etc. It is not uncommon for bird areas to be cleaned and disinfected very well but for Salmonella to be found on brooms, rakes, control panels etc.


You will need to plan in advance to ensure that an assurance scheme representative can come to test your house for Salmonella. Biosecurity concernes with visiting your site may significantly restrict their diaries. This visit will involve taking a very large number of swabs from the most difficult areas in your house to reach. If there is any muck, dirt, dust or debris remaining within the house it will be found, and swabbed. The vets who conduct this testing are trying to find even the smallest amount of residual Salmonella. Whilst this may seem harsh it is not in the industry’s interest to have another flock infected with Salmonella nor is it in your interest for your young pullets to become infected shortly after housing.

Despite your best intentions and endeavours it is extremely likely that Salmonella will be recovered at this time. Common areas where Salmonella can be recovered from include nest boxes, insides of metal tubes (eg perches), undersides of pop-holes, damaged nest box curtains or mats, expansion joints in the concrete, service area equipment, switches and control panels, gaps in walling material, door handles, inlets and exhaust vents. Once the results for the first swabbing have been received you should discuss with your vet to look at how any “dirty” areas are addressed and a further more targeted disinfection can be conducted. Once this is complete further official swabs will be required. Again you will need to liaise

Post Cleaning Swabbing

028

with your assessment scheme to manage this process. Any second swabbing will incur a cost to be borne by the producer. There is no limit to how many times the disinfection and swabbing can be conducted, however confidence in your ability to demonstrate conformity with your assurance scheme will be significantly diminished if this occurs too often.


Your assurance scheme will expect that a suitable management plan for the range has been established and implemented. The plan may include scraping off old stone, ploughing, re-seeding, subsoiling, increasing drainage, removing co-grazers and point application of disinfectant products if necessary or appropriate. Your new flock will receive official Salmonella tests by an APHA officer between 22 and 26 weeks of age and birds are required to have had access to the range by this time. All areas around the house must be cleaned and disinfected. During delivery of pullets movement of people and vehicles must be managed at this time to prevent the introduction of Salmonella.

Your new birds will require a dose of competitive exclusion product (eg Aviguard or Broilact) shortly after housing. You may also wish to consider including a feed additive with proven effect against Salmonella. These products are generally acidifiers and can be useful in helping to prevent Salmonella infection. Acidification of water through flock life may also be useful in preventing re-infection of subsequent flocks. Alongside auditing of vaccine administration which will need to be arranged by your pullet rearer, it is strongly advised that an additional inactivated Salmonella vaccine is administered before the birds are placed.

Other Areas for consideration

030

From the moment that Salmonella is identified biosecurity procedures need to be properly policed and reviewed daily to ensure that the infection remains contained in the first instance and that the house remains clean once cleaning and disinfection has been conducted. Vermin control is paramount on any farm where Salmonella has been identified. Rodent control should include effective baiting but also rodent proofing of the house and general farmyard tidiness. Where significant rodent populations exist, a wildlife biologiest may be consulted. Testing of co-grazing livestock, pets and staff members may be conducted to identify whether there are any carriers of infection on the farm which may jeopardise future flocks.


A BRITISH FREE RANGE EGG PRODUCERS ASSOCIATION SUSTAINABILITY FUND REPORT

Documents

A PRACTICAL GUIDE TO SALMONELLA INFECTIONS …...A brief introduction to Salmonella and its controls is offered in the first 2 chapters with the rest of the booklet (beginning on page