Antibiotic free farming is not difficult

John Carr

Farming without antibiotic medications is not difficult, but does take a steely determination by the whole health team to want to make it happen.

Before, embarking on an antibiotic free farm regime, a health team needs to be constructed. This needs to involve the owners, manager, stockpeople and the veterinarian. But it also needs the understanding of the genetic and nutrition suppliers. A degree of openness is required which is alien to many farms that are more used to a degree of silence about actual farm events. This takes trust and honesty. Each member of the farm health team has specific roles; the veterinarian plays the vital role of the “pig” speaking up for the animal’s biology and is the “honest broker” with robust checking systems.

Antibiotic free farming must not be at the expense of pig welfare and well-being.

Antibiotic free farming is about getting the management right:

· Management of pathogens

· Management of pig flow

· Management of immunity

· Management of the environment

· Management of any compromised pigs

· Management of people

Management of pathogens

It is hard enough to develop control programmes for the existing farm pathogens and opportunists as well as having to contend with new pathogens being introduced into the farm. The farm health team needs to develop active biosecurity protocols against all the natural routes of threat to the farm

Lack of discipline and carelessness are the major threats to a pig unit. This is largely associated with greed or a panic response to “improve”. If the farm has good health, do not throw it away on a pipe dream of a “better” greener pig on the other side of the fence.

The key component of biosecurity is to control pigs, in all their forms, entering the farm while at the same time allowing for genetic improvement. Farmers place enormous faith in genetic supplier’s health programmes and yet this is not at the top of many genetic suppliers’ daily concerns.

Pathogens enter farms through:

• Location – airborne pig pathogens
• Live animals – gilts, boars and semen
• Faeces from live animals –on trucks: dead animal, slaughter, animal, feed and general vehicles
• Other vectors: boots, clothing and soiled equipment – pig faeces

Farms break with new pathogens or new variants of current pathogens – for example Porcine Reproductive and Respiratory Syndrome virus. Location, location, location is the key. If there is a farm with frequent health problems and purchasing live pigs from markets, there is little chance that any neighboroughing farm within 1 km will be able to maintain an antibiotic free status and still meet the welfare requirements of their pigs. Antibiotic free may be achieved on a regional basis, but with farms under different ownerships, tensions and greed arise which can break the system. The veterinarian has a role here as honest broker, but this role needs to be carefully explored, possibly legally, before the venture even starts.

Minimum requirements for an antibiotic free system

Location – The farm should be 1 km away from adjacent pig farms.

An isolation/acclimatisation area is essential, which then runs as a strict all-in/all-out programme – which therefore, may require multiple isolation areas. Each isolation area needs to be at least 50 metres from the main farm and obviously each more than 1 km from adjacent farms. The prevailing wind should be from the main farm towards the isolation areas. This can prove impossible in many parts.

Overall biosecurity – no pig farms within 1km of farm or isolation area. No major road within close proximity
Prevailing wing Major road Green-Farm Black- Isolation (ideally there should be 2 or 3 areas to allow 6 weeks isolation)			Edge of the One kilometer zone from main farm Edge of the One kilometer zone from isolation area(s) No farm within zones
Whole farm biosecurity – location of dead stock area, isolation, manager accommodation, slurry systems
Main farm Dead animal Compost Slurry lagoons			Farm gate Manager house Isolation area 1 Isolation area 2
On-farm biosecurity – location of risk areas: internal roads, feed bins, loading areas
On – farm Highlighted in green Farm buildings Perimeter				Off-farm Perimeter Straw compost Feed bins Farm entrance High risk area Loading area Feed bins Car park
Note the farm entrance is both on and off farm as the shower is the dividing line Note the high risk area used by “off-farm” vehicles is highlighted

Good lines of communication between the genetic supplier’s veterinarian and the farm veterinarian. The genetic company should prepare a health declaration and be willing to prioritise the antibiotic free farm with regard to health information. Consistent and quality gilt supply is an essential component to pig flow.

Dead animal disposal has to be away from the farm or utilise burial, incineration or, ideally, composting. This depends on local legal constraints.

Truck hygiene has to be well understood, especially trucks which take animals to the slaughterhouse. In an ideal world, feed and animal movements should be on a Monday after the trucks are not used over the weekend. But the farm has to realise they live in the real world. But they can still expect clean vehicles. In PRRSv negative farms, trucks can be heat treated prior to use.

Vermin control has to be pro-active. Buildings should be bird proofed where ever possible. Flies and mosquitoes should be controlled and buildings even fly proofed with a 2mm screen. Note that screens will need to be cleaned regularly to allow air flow. It is vital to reduce surfaces of standing water – pockets in lowered curtains, old tires or buckets as example. Rodents should be minimized with active control programmes utilising numbered bait boxes scattered around the farm and regularly checked. Any aspect that requires regular checking should have an active monitoring programme in place. Utilise natural resources such as Barn Owls and bats to control the rodent and biting insect’s levels off-farm.

On-farm and off-farm concepts. It is imperative for all visitors and staff to wear on-farm clothing (especially outer clothing) and boots. The first thing a pig does when a “stranger” enters their pen is to lick and examine their boots and clothing in great detail and if these items come from another farm – pathogen transfer occurs.

Rectal thermometers should remain on the farm and not move between units – even on multisite systems.

Farms should have their own basic environmental monitoring and postmortem equipment. There should be few items advisors need to bring onto the farm. A on-farm digital camera with video playback capability and the internet can be a great resource to assist communication between farm health team and veterinarian.

Cleaning of batch areas

Antibiotics are used to treat sick pigs or prevent pigs from getting sick and thus enhance their welfare. As this immediate fall back position is not readily available, the antibiotic free farm needs to minimise contact with pathogens. Pathogen reduction is achieved by removing all faeces and allowing the room to dry.

Remove all feed from feeders	Remove all pigs and faeces. Dampen and wash room	Disinfect room/water/air/feed – in this case lime washing is used as a terminal disinfectant

Cleaning needs to be done in a formal manner with an agreed procedure. Cleaning must include all the components of the environment – water, feed, floor and the air.

The cleaning protocol as a minimum must include:

• Remove pigs and feed. All the pigs must be out of the air space before cleaning starts. To reduce costs, the pigs must eat all the feed as they leave the room. Food cannot be washed down the slats and obviously cannot be left for the next group (total lack of all-in/all-out) or even moved to another group.
• Remove all disposable equipment. On normal farms this should include any syringes and needles.
• Dampen the room. This significantly improves faecal removal. Having sprinkler systems already installed into the ceiling is extremely helpful.
• Apply a detergent. This step is still forgotten on most farms. But to remove the most faecal material, grease and animal oils need to be removed by the detergent first.
• Hot pressure wash. Antibiotic free farms should adopt a hot pressure washing programme after the detergent phase. Do not use too high a pressure and ideally use a fan jet nozzle.
• Note all the room requires cleaning – floor, ventilation, feed and water supplies.
• Disinfect the room. A cheap useful disinfectant is burnt builder’s lime – CaCO₃. The additional advantage of lime-wash is that the operator can easily see which areas have or have not been disinfected. Disinfect the water supply.
• Air the room and flush the air system.
• Check that no aspect of the room requires repair and maintenance. Note especially the water supply and any mechanical ventilation systems.
• Allow the room to dry. This single step kills most pathogens.
• Restore the room to the required ambient air temperature before the new arrivals. Ideally at least 1⁰C above the temperature of the previous room the pig’s were occupying.

Reducing internal spread of pathogens – note flies and needles

The concept of all-in/all-out is when a problem occurs during one batch; it does not spread to the next batch. However, while the farm designs and adopts a pig flow batch, the advantages can be lost by the lack of internal biosecurity.

Reduce the internal spread of pathogens:

· From weaning to 30 kg (10 weeks of age) the stockpeople wear a different specific coloured set of boots for each batch of pigs.

· In the farrowing area, each batch should have its own brush and scrapes, ideally colour and number coded.

· Do not move oral medicators, needles and syringes between batches of pigs.

· Footbaths can assist by improving stockpeople attitude and can disinfect clean utensils. Brush clean all boots before using the disinfectant footbath.

Always examine the healthy pigs before any sick pigs and move from the youngest to oldest pigs.

On many farms initial buildings were sited too close to each other to allow for strict internal biosecurity. Farms must make the best of the materials offered to them.

Partial depopulation and pathogen elimination

Before, embarking on an antibiotic free regime, the elimination of certainly pathogens would make the enterprise more likely to succeed. The major pathogens which should be removed from a commercial farm would include: Brachyspira hyodysenteriae (Swine Dysentery), Sarcoptes scabiei var suis (Mange), Mycoplasma hyopneumoniae (Enzootic or Mycoplasma pneumonia), Porcine Reproductive and Respiratory Syndrome virus (PRRSv) and Aujeszky’s Disease. It is assumed that the farm is free of major OIE pathogens or active vaccine programmes are in place to control the pathogen.

Brachyspira hyodysenteriae	Sacoptes scabiei var suis	Mycoplasma hyopneumoniae
PRRSv	Aujeszky’s Disease

Certain pathogens may be difficult to remove, but the acute clinical signs of the disease should be absent from the farm – these would include Streptococcus suis II et al., (Meningitis), Haemophilus parasuis/Mycoplasma hyorhinis (Glässer’s), Escherichia coli F18 (Bowel Oedema) and Actinobacillus pleuropneumoniae (APP).

Meningitis	Glässer’s	Bowel Oedema	APP

Management of pig flow

It has been well proven that placing pigs in a clean environment which is dry and warm (appropriate temperature) will perform better than pigs placed in a dirty environment. Pigs stressed by a “clean damp cold” room will die or at least not perform.

Antibiotic free farming is about kg sold per batch, not achieving a “1000” sow unit. Take the “fun” out of pig farming, the farm must be routine, run as a business, batch on batch, year on year. Farms need to be “profit driven” not “production target driven”.

Adopting the batch concept

Any farm attempting to have an all-in/all-out programme must run a batch system. Batching is about producing a group of pigs all the same age (maximum a week variation) to move, as a batch, through the farrowing house, nursery and then grow/finish.

It is amazing how the rigors of all-in/all-out are not grasped by the pig industry.

All-in/all-out is not:

• In over time
• Almost all out before in
• All in, plus a few more later
• All-in, but variable numbers per batch
• Some this week, next week and the week after, but then all-in/all-out!
• Continuous flow farrowing, but all-in/all-out nursery and then continuous flow finishing (or any variant of above)!

All-in/all-out starting point

All-in/all-out must start in the farrowing area. The farm health team needs to analyse the farrowing area to produce batches that will create individual air space groups that are identical batch after batch. This might result in the need to subdivided or combine farrowing rooms.

In general there are only a small number of possibilities resulting in even batches that are repeatable over a calendar year.

These options are:

Number of farrowing rooms required to allow for all-in/all-out

Batch time Weaning age	0.5w	1w	1.5w	2w	3w	4w
3 weeks	8	4		2		1
4 weeks	10	5	3		2
5 weeks		6		3

Batch times in weeks

Within the EU all piglets must be a minimum of 21 days at weaning – thus three week weaning is illegal. Piglets less than 28 days of age must be weaned into specialized accommodation.

On antibiotic free farms, weaning should occur at 4 weeks or more to maximize weaner weights, especially from gilt litters, thus reducing producer’s batching options further.

Correct stocking densities assist health

The purpose of instigating a pig flow model is to eliminate over and under-stocking of the farrowing house, nursery and finishing area. It is only when a room is empty of pigs can it be cleaned and as importantly maintained. It is impossible to fix broken drinkers and feed lines with pigs biting the back of the stockperson’s legs and getting under their feet.

The farm must resist the temptation to “make up” losses by over producing later on. This particularly involves post-summer heat issues which have resulted in a reduced farrowing rate and slower finishing growth.

The slower summer finishing growth implies that with a fixed number of buildings (there needs to be one air space per batch) either there should be empty buildings in the winter months, when growth is faster or that lighter animals are sold in the summer. The choice is the farmer’s, the authors personal choice is that buildings are rested more in the winter months, allowing more time for drying – the number one disinfectant. This again means that farms should not be managed purely on a kg/sold/sq metre production target as this must vary over the year.

On many farms nursery and finishing buildings are of a variety of shapes and sizes. Farming in the European Union when finishing pigs to an average liveweight weight of 110 kg, each pig must be provided with 0.65 m^2 by law. Therefore, a 65 m^2 building has room for 100 pigs to finish, not 120. This infuriates some producers, but this is the law. If there are only 80 pigs weaned – it will be impossible to finish 100 pigs – 20 pigs (plus post- weaning mortality will be lost and add to the fixed cost of production).

Farmers cannot add 20 pigs from another batch nor can they attempt to push 120 in the next batch to make up the loss.

When farming without antibiotics it is imperative that the pigs are not overstocked and that stocking rates are adhered to in practice.

The second inevitable event the health team must accept that if the farm is described in terms of sows, for example a 1000 sow unit, the production of pork/bacon must vary as farrowing rates will fall over the summer months. This variation in output can be 15% over the year. To stabilize the pork/bacon output the herd size must vary – being bigger at the beginning of summer and smaller at the beginning of winter.

Example of herd size variation with the season

Farm selling 190 pigs a week – 5% post-weaning mortality

Summer batches	Rest of the herd batches
70% farrowing rate	85% farrowing rate
520 sow unit	480 sow unit

Summer time	Winter time

The adult farm needs to be described in terms of a fixed unit and the batch farrowing place is an excellent unit.

Once this is adopted as the unit of measure, the whole farm can be easily described from gilt requirements to vaccine requirements per batch – an integral component of farming without antibiotics.

Records need to be organized around the batch of pigs. No producer batches monthly (28 to 31 days depending of the moon?) so the monthly recording system must be scraped. In addition, which day is day 1 of the batch? It is the day after weaning. It is essential to ensure that all gilts and returns which are mated on days 1 to 3 are included in the correct batch. Otherwise weaning age is affected and batch records are difficult to interpretate.

Management of immunity

Innate Immunity

The best immunity is using animals which have no receptor sites for the “pathogen. The selection of pigs and the use of DNA mapping will enhance our knowledge of pig’s natural resistance to pathogens. Lines of pigs are already commercially available that are “resistant” to Escherichia coli F18 (Bowel Oedema) and F4 (K88) (Pre and Post-weaning diarrhoea). Several breeding companies are already recording resistance to diseases and disorders within their selection pressures, for example not selecting future gilts and boars from sows and gilts whose piglet’s demonstrate to pre-weaning diarrhoea.

This piglet should not be selected for future breeding as they have demonstrates a tendency towards having pre-weaning diarrhoea

Acquired immunity

Preventative medicine programmes rely on a healthy immune system being stimulated via effective vaccines or autogenous pathogens using materials such as feedback programmes or direct exposure.

Immune suppression

Any agent or factor which can reduce the pig’s immune system should be avoided. For example mycotoxins can be introduced into the herd through feed, poor feed storage or bedding. A careful review of these items is required by the health team. It may be better to use old rotten straw for composting rather than bedding, especially if it results in either an abortion storm or a PRRSv break though affecting the gilt’s immune system.

Pathogens can affect the immune system SIV is a prime example. If the herd undergoes a SIV break, this may affect the gilt’s immune response to the preventative medicine vaccine programme. This may result in the need to extend the isolation and acclimatization time or revaccination. The batch must still be achieved.

In the piglet and weaner, iron anaemia can result in ill-health particularly post-weaning diarrhoea. Proper administration of iron at 3-5 days of age by injection is advised. Note iron should not be administered to piglets which have diarrhoea. Iron supplementation is not required if the pigs are pasture reared.

Mycotoxins	Swine Influenza	Iron anaemia

a) Adult herd

Healthy adult herd

New animal introduction

A major risk to the herd’s health is the deliberate introduction of live animals into the herd. This risk can only be mitigated by time in isolation allowing any pathogen which the new animals are incubating, reveal themselves. And, if possible, become none excreting before the animals are introduced to the main herd. The gilt or boars also require time to become acclimatised to the farm’s native “pathogens”. Swine Influenza viruses are an excellent example, whereas if the new gilt is excreting the virus, isolation and acclimatisation allows the gilts to recover and stop excreting virus before joining the main herd. Or affected gilts or boars can be recognized and immediately culled before infecting the main herd. If the farm is large enough parity segregation should be practiced.

Of the major pathogens, which gilts and boars need to acquire on positive farms, the most important is Porcine Reproductive and Respiratory Syndrome virus. On positive farms, adopting an antibiotic free system, must ensure that gilts are positive to the native PRRSv variant and will not introduce “new” variants into the main herd. To allow for adequate time for the virus to infect the gilts and excretion stop and be available for breeding at 220 days of age and 130 kg live-weight, the gilt needs to enter the isolation area at 60 kg or earlier.

Female genes

The farm has two major options to obtain new breeding gilts – essential for efficient pig flow batches.

1. Breed their own gilts

If this is the health team’s decision it is still essential that the gilts are introduced and acclimatised to the adult herd before entering the breeding unit. Note again the gilt should leave the finishing herd at no later than 60 kg liveweight to allow adequate isolation and acclimatisation time. Selection of gilts should start at the breeding of the mother and father and not just looking at this week’s finishing herd.

2. Purchase breeding gilts from a genetic supplier

These are often sold at breeding weights – 105 kg or more. But this means there is little isolation and acclimatization time allowance. This can be a disaster on farms practicing a no antibiotic free period. Therefore, as stated previously, future breeding gilts should be purchased from the genetic company at 60 or even 30 kg liveweight. This needs careful discussion with your genetic supplier.

If the farm is large enough, parity segregation should be considered as a better option to reduce risk of pathogen introduction and spread around the farm.

Male genes

Teaser boars should be from on-farm stock.

Male genes should be obtained through (artificial insemination) AI. In general terms AI is a highly proficient and biosecurity safe method of moving male genes.

A PRRSv negative unit should practice on-farm AI

If the farm is PRRSv negative, on-farm AI should be practiced to reduce the chance of introduction of PRRSv through semen. Only a few boars need to be purchased (1 for each 100 sows), and while they should enter at 100 kg, or more, so their genetic potential can be proven by the genetic supplier. However, their biosecurity can be ensured as they can then remain in isolation for several months without compromising their reproductive efficiency.

Depending on the location of the farm other pathogens may also pose the same risk as PRRSv and the health team needs to take these pathogens into consideration if they can be transmitted by semen or gilts: Post-weaning Multisystemic Wasting Syndrome, Foot and Mouth Disease and Classical Swine Fever could be contenders.

Parity profile

A herd’s natural immunity can be disturbed by the introduction of large numbers of gilts. This can be prevented by monitoring closely the parity distribution of a herd to a 3.2 parity average. The pig flow model will predict the number of gilts required allowing for careful planning of isolation. It is not unusual for “outbreaks” of Enzootic (Mycoplasma) pneumonia or Porcine Reproductive Disease Complex (PRDC) to be associated with a sudden increase in the proportion of finishers from gilt litters.

Likewise, if the herd age increases, while this can enhance herd immunity, the sows aged past parity 7 have lower number of piglets weaned, thus causing variable output, this cannot be tolerated.

A suggested parity profile:

Parity distribution	0	1	2	3 to 6	7+	Average
Percentage of adults	17	15	14	48	8	3.2	parities

Gilt purchasing needs to be carefully balanced by the batch’s requirements. Discuss this with your genetic supplier.

Vaccine health

To reduce the necessity of antibiotics, the health of the adult herd needs to be enhanced by the use of vaccines. Commercial vaccines to many pathogens are available. It is not necessary for every possible vaccine to be used to allow antibiotic free farming; however, a greater reliance on vaccines will be required.

Some vaccines are strongly advised:

For sow health

• Erysipelothrix rhusiopathiae to gilts in isolation and before farrowing or at weaning.
• Parvovirus to maiden gilts in isolation to help stablised pig flow.
• Lawsonia intracellularis to maiden gilts in isolation.

For offspring health through colostrum

• Escherichia coli to gilts and sows pre-farrowing. Ideally use oil based long life vaccines, so the vaccination can be administered at breeding and not to the gestating sow and most certainly not during lactation.
• Haemophilus parasuis to gilts and sows pre-farrowing, these vaccines appear to produce the best control of Glässer’s in weaned pigs when administered to sows 3-6 weeks pre-farrowing.
• If an effective vaccine to Streptococcus suis II is locally available, this should also be administered to the adults if possible.

For finishing pig health

• Porcine Circovirus II vaccines should be administered in all farms with endemic PMWS to weaners before the age of 5 weeks.
• Mycoplasma hyopneumoniae should be administered at weaning on all farms which are positive to the bacteria.
• Lawsonia intracellularis administered through the water supply or manually orally at weaning.

These comments do not take into account legal requirements for vaccination – Aujeszky’s disease or Classical Swine Fever or local prevalent pathogens – Salmonella cholerasuis for example, as advised by the health team.

However, if vaccines are not stored properly, they will be inactivated. Being delivered to the farm on a cold winter’s day frozen negates the whole programme. All vaccine stores along the entire chain should be monitored. All farmer medicine stores should have maximum/minimum thermometers and temperature monitored at least weekly. If the vaccines have been suspected of being frozen they cannot be relied upon and therefore, must be disposed.

Transport to the farm – avoid temperature extremes	Poor refrigerator storage – vaccines must not be frozen	Needle length and route of administration

Administration process

Irrespective of the vaccines chosen by the health team and their excellent storage, inappropriate administration, classically using too short a needle, depositing into fat tissue rather than vascularised muscle tissues, may negate the whole programme.

Note the pig’s actual age when vaccines are administered and consider any maternal interference in several vaccines. Erysipelas and Parvovirus vaccines are examples which cannot be administered at weaning. Do not unnecessarily raise maternal colostrum protection where possible; for example avoid PCV2 or Mycoplasma hyopneumoniae vaccines to pre-farrowing sows when piglet vaccination is going to be carried out as maternal immunity will affect the proficiency of the piglet vaccine process.

Even with dead vaccines, post-vaccinated animals may feel unwell for a day or so. Therefore, avoid periods when this can impact production – for example, never vaccinate lactating sows. If the sow goes off her food this will negatively impact weaning weights, post-weaning growth and post-weaning mortality, wean to service intervals, farrowing rates and subsequent litter size.

Covering pathogens not available in vaccines

Feed-back programmes

Gilts and boars, both purchased from outside or homebred need to be acustomised to the background pathogens, especially any reproductive pathogens (including pathogens resulting in congenital defects), before being bred. The easiest method of achieving this is to take faeces from nursery pigs (if the farm flow layout allows) and farrowing house materials – faeces from sows and piglets (especially any diarrhoea), stillborn and mummified materials. Bedding from farrowing paddocks or pasture raised pigs can be a good source of feed-back material.

The classical agents which are stabilised using these materials are Parvovirus and other SMEDI viruses (Enteroviruses and Circoviridae) and agents responsible for congenital tremor (as yet unrecognised).

Feedback materials assist in preparing the gilt’s immune system to produce adequate colostrum in order to protect their future piglets. The pathogens here include Rotovirus, Escherichia coli various strains (F1, F4, and F5 as examples) (note colostrum will not protect against post-weaning F18). But also the often forgotten protection offered by colostrum to Staphylococcus hyicus (Greasy Pig Disease), Streptococcus suis (meningitis); Haemophilus parasuis, Actinobacillus suis and Mycoplasma hyorhinis (all resulting in polyserositis- Glässer’s disease). On farms practicing an antibiotic free regime this material should be reintroduced to all pregnant sows 6 weeks pre-farrowing.

b) Piglets

The runt pig

Piglets born less than 800g should be euthanased at birth before they have suckled any colostrum. Colostrum is limited gold and must be used wisely. Do not waste colostrum on piglets which have a 90% of dying. It is still possible to target 10.5+ weaned per litter with this policy. If piglet birthweights are low, review pre-farrowing feeding routines and management.

Gilt litters

Ideally all gilt litters should also receive some colostrum from an adjacent sow by spilt suckling. But note this has to be within 6 hours of birth. This can increase growth rates of the piglets by 60g a day and reduce the mortality by 50%. Sow colostrum can be obtained by milking the sow using a human breast pump, but this is very time consuming.

Infectious load

Reduce the infectious load in the piglet by excellent cleaning and drying of the farrowing accommodation. Washing the sow pre-entry into the farrowing area reduces faecal contamination of the udder and reduces the number of parasite eggs such as Ascaris suum. In non-pasture reared sows remove the faeces from behind the sow 3 days pre and post-farrowing.

Coccidosis

Isospora suis is an insidious pathogen of piglets and results in chronic, often subclinical injury to the small intestine. This major impact of this subclinical infection can be is a reduction in weaning weights of 0.5kg. Any reduction in weaning weights should be avoided as it reduces post-weaning growth and resistance. Control of Isospora should be practiced by the administration of a toltrazuril-like product at 4 days of age.

Iron deficiency anaemia

Sow’s milk is deficient in iron. The piglet naturally would acquire the necessary iron from eating soil from the farrowing nest environment. If the farm is not farrowing on pasture, it is essential to ensure all piglets have an iron injection at 3 - 10 days of age. Poor iron blood levels may be revealed by an increase in post-weaning diarrhoea and, when extreme, pale weaners. Ensure needles and equipment used for administration of iron is of the highest quality. Change needles between litters.

Blood borne pathogens

Do not unnecessarily spread blood borne pathogens between litters, for example Mycoplasma suis and PRRSv. Take care with castration blades between litters. At maximum use one needle per litter and do not go between litters. Do not move automatic syringes between rooms and batches without sterilization. Watch teeth clipping, tail docking and ear notching equipment.

Teeth clipping	Tail docking	Tattooing
Ear notching	Castration	Needles and syringe

Avoid piglet growth limitations

All measures which may reduce or interfere with the piglet’s growth should be avoided, this includes most piglet processing – teeth clipping, tail docking, castration and ear notching. Fostering should be practiced in the minimum and only to even up litters and not after day 3, unless absolutely necessary.

Avoid all vaccines to lactating sows as these may reduce sow feed intake and practice all known methods to enhance lactation output. Lactation output can be influenced by a range of measures – but particularly avoid overweight pregnant sows, temperatures in excess of 20°C in the farrowing house (provide adequate cooling when ambient temperatures exceed 24°C), low water availability.

Birth to Weaning

Avoid fostering wherever possible. Evening up of litters by day 3 post-farrowing has enormous benefits. But fostering after day 3 lowers total weaning weight. Placing extra piglets on gilts helps to drive milk output from the gilt and gilt lactation feed intakes.

Mimic nature’s natural piglet socialization by mixing two litters of piglets on day 10 and then 4 litters on day 14 all within the same batch. Pre-weaning mixing has little influence on weaning weights, but does improve post-weaning growth and behaviours. Never move piglets back into a younger batch.

c) The weaned pig

Weaning the pig

Weaning the pig is extremely stressful. The weaned piglet has little idea where to eat, drink, sleep or defecate, especially in a new foreign environment. If the building has been adequately cleaned, the natural landmarks have disappeared. It is essential that you create these environmental signals. A big pen environment is the easiest to assist this.

• Create a sleeping area away from any draught (less than 0.1m/s) and water supplies.
• Create a defecation area which is cold, damp, possibly draughty (about 0.3m/s) and dark/dim.
• Teach the new weaner when and how to eat – note on day of weaning they were being fed every hour by their mother – who told them when to eat. They are not hunger driven.
• Provide “lavish” amounts of freely accessible water – not from a nipple which has low flow rates and is out of reach (because it is still set for the previous 30 kg pigs).

If your weaners “scream and wail” for long periods of time in the post-weaning period, review weaning protocols – it is not natural.

Sleeping area
Draught free <0.1m/2	Warm 30⁰C (at 7 kg)	Dry	Light 200lux
Toilet area
Draughty – 0.3m/s	Cold 24⁰C	Wet	Dark less than 40 lux

Classic mistakes

Combined sleeping and water area	Why are pigs in these two “identical” pens in the same room sleeping in different patterns?

-Hot and damp! Is this the area a sleeping or defecation area? The farm team needs to think “pig”.

Vaccines at weaning

Administer vaccines to the pig where applicable. Ileitis (PED, PIA, Lawsonia intracellularis) occurs on most farms. Live vaccines are available which can be administered at or even before weaning.

Farms with other disorders may have to consider the practicality of administration of vaccines to cover the conditions Escherichia coli (F18) Bowel Oedema), Aujeszky’s Disease or Salmonella cholerae-suis. There are some conditions, where farming without antibiotics would not be in the welfare interest of the pigs and the pathogens should be removed first – these could include Brachyspira hyodystenteriae (Swine Dysentery), Classical and African Swine Fever.

Streaming – not all pigs are born equal

The smaller 10% of pigs at weaning should be removed from the main group, given special attention and time to adapt to their circumstances. On many antibiotic free farms, these are actually removed from the system altogether and farmed along traditional lines with the use of conventional prophylactic treatment methods. This also allows for any fall-out pigs from the antibiotic free group/room/batch to be treated humanely.

d) Grow/finish

It is essential that the pigs remain in their own cohort. Neither pigs nor materials from other pigs or batches should enter their environment. Ideally, on batch antibiotic free farms, a wean to finish system should be employed as this reduces the pigs exposure to novel pathogens.

Management of the environment

The environment can be broadly broken down into: Water, Food, Floor and the Air.

Within each of these four factors, set parameters should be drawn up by the health team and ideally posted in a prominent position – for example on the entry door. The health team should be provided with suitable equipment to measure and adjust the environment of the pigs.

Environmental factor	Typical examination	Equipment required
Water	Height of drinkers Flow from drinkers Quality of water Position of drinkers Pig’s behaviour	Tape measure Cup and timer Total dissolved meter, taste Eyes Observation
Food	Length of feeder Position of feeder Quality of feed Quantity of feed being fed Pig’s behaviour	Tape measure Eyes Taste Food sieve Weigh scale Observation
Floor	Floor area Quality of floor Pig’s lying behaviour	Tape measure Hand/roughness Observation
Air	Temperature Humidity Air speed/draught Gas concentrations Pig’s sleeping and defecation behaviours	Thermometer Hygrometer Vanemeter, Smoke sticks Nose, eyes, sensors Observation

Basic environmental assessment kit

The building prior to the pig’s entering must be suitable for the animals on entry. The building must be capable of maintaining a suitable environment for the entire duration of the animal’s occupancy. Animals are not to warm and dry the building. Ensure drinker heights are set correctly. Drinkers set for 30kg pigs must be lowered before the next batch of newly weaned pigs before entry. Post-weaning pigs need a different feeder space then pigs weaned 5 days. Air movements acceptable for adults are not acceptable for piglets which will be chilled. Adult sows will be heat stressed if kept at 30⁰C, whereas the newborn piglet is comfortable. Animals should enter a building that is 1⁰C warmer than the building they just left.

Management of compromised pigs

The compromised pig is a major health threat to the farm as well as creating enormous welfare problems. Farm staff must realize that euthanasia is a good welfare option and keeping crippled pigs alive is cruel.

Compromised pigs can be broadly divided into six areas:

At birth

• The runt – less than 800g birth weight and/or poorly muscled.
• Pigs produce large number of offspring and not all of them are capable of producing a finishing pig. Commercial piglets with a birthweight less than 800g have only a 10% chance of survival to finishing. Unless specialist care can be given, these pigs should be euthanased, ideally at birth, before they have consumed colostrum which might help other smaller pigs survive.
• Pigs born with deformities that will interfere with slaughter
• Pigs which are born with deformities of the mouth (cleft palate) or severe feet issues – arthrogyphosis, no toes on one foot.
• Once it can be determined that the piglet will not be likely to survive until slaughter it should be euthanased immediately.

Poorly muscled pig	Congenital deformity – arthrogyphosis and fused toes	Poor doing pig

At weaning – pigs less than 4 kg

• Pigs of low weaning weights for example for 18-24 day average 4 kg or less should be given special care in the form of a nurse sow/gilt, specific accommodation or euthanased. If there are any deformities in these pigs, such as hernias or joint ill for example, they should be euthanased.

Small pig at weaning	Hernia – large scrotal and/or umbilical	Joint ill

During grow/finish

The veterinarian should produce a formal advice booklet regarding the care of compromised pigs. The farm should be encouraged to adopt a “7 and 14 day rule” concept. Here when compromised pigs are discovered they are: inspected, individually identified and if necessary hospitalized or immediately euthanased (broken legs, severe tail biting, rectal strictures for example). The pigs are then examined at least twice a day and reassessed. On day 7, assuming euthanasia has not happened, a thorough examination should be carried out, ideally by the farm manager and a formal decision made to continue for an additional 7 days or to euthanse the pig.

At 14 days, another careful examination is made. If the pig has not recovered it should be euthanased.

During the routine veterinary visit, a careful clinical examination of the hospital area is essential.

Severe tail biting	Broken limbs	Rectal stricture

The hospital area posses unique challenges to all-in/all-out programmes. Animals moved to the hospital area cannot be moved back into the main group.

Comment

Production figures should be about realities rather than just numbers. Killing pigs on the first of the month, to reduce last month’s figures is not acceptable.

Management of people

The success of an antibiotic free programme are the stockpeople. Training, encouragement and provision of confidence in the system is essential. Stockpeople need to realise that they cannot cheat the system. Antibiotics are easily revealed in the slaughterhouse and food processing laboratories. Destruction of the system is easy, just foster piglets, avoid all-in/all-out programmes, over- and under-breed, lie and mislead advisors and management staff. But in the end the pig will reveal all.

Change the goals of the farm away from being production target driven towards a profit driven farm. Areas to note would include:

Weight/numbers weaned per batch rather than pre-weaning mortality.

Number of empty farrowing places rather than farrowing rate.

Number of empty shackle places rather than pigs per sow per year.

Empty farrowing crates	Weight of pigs weaned Picture shows weigh scale	Empty shackles

Which is the better farm? Consider which scenario describes your client’s farms.

Typical family farm 10 sows a week batch farm

Farm A	Farm B
Preweaning mortality 8%, numbers weaned 9.5 per farrowing place	10 weaned per farrowing place and a 12% pre-weaning mortality
A 90% farrowing rate and 9 sows farrowed this batch	10 sows farrowed this batch with a farrowing rate of 76%
5% post-weaning mortality from weaning to 110 kg liveweight	7410 kg of deadweight paid for this batch
2.3 litters per sow per year	385320 kg of pig meat sold per year
23 pigs per sow per year	7410 kg deadweight produced for the last 52 batches
I get $1.00 unit per kg income	My real cost of production is $0.95 units per kg
I vaccinate against every possible pathogen	I make a profit

Production targets only matter once the farm is profitable

Moving from a traditional farm towards an antibiotic free farm

The following programme has worked on a number of units. The programme takes around 2 years to complete.

Current farm	Antibiotics to 70 kg liveweight in the finishing herd
1^st phase	Remove antibiotics from adult herd
	Remove antibiotics from growing pigs older than 30 kg
2^nd phase	Remove antibiotics from weaned pigs older than 18 kg
3^rd phase	Remove prophylactic antibiotics from all healthy pigs Use only injectable or oral medication for the compromised pigs
4^th phase	Separate all medicated compromised pigs from main farm unit

· Management of pathogens

· Management of pig flow

· Management of immunity

· Management of the environment

· Management of any compromised pigs

· Management of people