VM02103 Proactive Health Management – the influence on antibiotic usage in pigs

Executive Summary

This study was carried out with the GB pig sector over a period that included outbreaks of Swine Fever in eastern England, Foot and Mouth Disease nationwide, and the spread of Post-weaning Multi-systemic Wasting Syndrome (PMWS) through the country from south to north. Collaboration from the industry has been supportive in spite of the difficult times. The design of the project was intended to answer the original request for information on the use of antibiotics in the national pig industry. It also intended to answer further questions on the background to the use of medication, namely the general prevalence of disease and the current status of health management on pig farms. The detailed analysis of farm practice was confined to indoor breeder/finisher units to restrict some aspects of variability. The final part of the project investigated the impact of intervention on twenty farms on the use of medication and pig performance, using standard operating procedures (SOPs) relevant to health matters.

The results from the study indicate that in contrast to the professional behaviour of some within the sector there is a lack of transparency in disease matters that is ultimately damaging to the health of the national pig herd. The concept of risk, and risk management, is not particularly well appreciated, and as a consequence the diligence of some operators in health matters is negated by weak practice elsewhere. However, the report represents a substantial health audit of the pig industry, and the next step is to support the good practice seen on farms, communicate the positive results to the industry, and encourage dialogue throughout all parts of the industry to increase transparency on health matters.

The main report is presented in two parts; part 1 contains results from 26% of GB pig producers with >100 sows or >1000 pigs who responded to a postal questionnaire. The questionnaire addressed the frequency of treatment with antibiotics and vaccines, incidence of disease, basic biosecurity, and attitudes towards use of antibiotics. Part 2 of the report contains detail of individual farm audits of biosecurity, environment, feed, water and waste management relevant to pig health, and treatment practice, on 40 pig units across GB. Use of medication was monitored over two years on the 40 farms, and 20 received intervention support for approximately one year to assist health management and examine the potential of standard operating procedures (SOPs) at pig farm level.

Part 1

·  A mail survey of 1889 pig producers in Great Britain was undertaken to provide an overview of current antibiotic use and other health-related management practices in weaners and growers.

·  Responses were received from 482 farmers (26%). The 20% respondents with sows manage 24.3% of the national herd, and 477 farms (25.3%) manage an estimated 23.8% of all pigs in GB.

·  Post-weaning Multisystemic Wasting Syndrome PMWS) was perceived by 45% as the most important disease, with the other chronic diseases of PRRS and PDNS mentioned by 17-18% as the most or second most important problems. Pneumonia was listed as the first or second most important disease by 42% of respondents.

·  The majority of breeding and finishing units added antibiotics to weaner rations, and 49% to grower rations.

·  Twenty seven percent of farmers had treated suckling pigs with injectable antibiotics on at least a weekly basis in the last 12 months to deal with scours, and 13% had used water medication to deal with scour in weaners.

·  The use of antibiotics as growth promoters in weaning and growing pigs was reported by 50% and 44% of respondents, respectively.

·  Univariable analyses showed few associations between the use of antibiotics at a farm level and various other management factors.

·  The likelihood of using in-feed antibiotics was associated with membership in different types of pork quality assurance schemes. Use of in-feed antibiotics was less likely on smaller farms.

·  Outdoor breeding herds had lower expenditure on veterinary treatments than indoor breeding herds.

·  Growth promoters are no longer considered justifiable to 61.6% of producers, and producers’ opinion was significantly associated with actual on-farm use.

·  Biosecurity is highly variable. Almost 94% of farms have a visitor policy, 70% practice isolation of new animals, but 57% of farms allow stock vehicles entry to the unit.

·  The questionnaire database has provided a useful benchmark of practice in GB, and can be used to direct future resources towards managing the use of antibiotics in the pig industry

Part 2

·  Many farms had facilities in place to practice good biosecurity in specific but not all areas. Whilst the potential for improved practice is present there were significant gaps in biosecurity on too many farms.

·  There is a need for greater transparency on health matters within the industry. Only 4/40 farms either requested or received information on the health status of purchased pigs or semen.

·  The biosecurity standards of feed delivery companies were considered to be good, but the risks associated with feed delivery pipes and the locations of feed bins were generally less well appreciated.

·  Hygiene levels in the farrowing houses was generally very good, with 39/40 (97.5%) farms scoring 4 or 5 on a five point scale from poor to good. Cleaning practice tended to include a period of soaking, but detergent use was less common. All farms used high pressure washers and there was little appreciation of the risks caused by aerosol contamination

·  Pressure on sow/piglet health is increased by uncontrolled increase in stocking density/throughput in the farrowing houses. Three intervention farms have now moved to batch farrowing systems, with the specific aim of reducing the impact of disease.

·  All-in, all-out (AIAO) systems were used for weaner accommodation on 33/40 farms (82.5%) and cleaning practices were similar to those used on farrowing accommodation. However the industry can improve the impact of AIAO by applying SOPs; for example only 57% of farms cleaned feeders between batches of weaned pigs.

·  Improved management of the pig house environment was promoted by 79.2% of respondents to the postal questionnaire as an alternative to antibiotic use. Environment and environment control were highly variable on the audit farms, with positive correlations with pig performance. The ability to provide clean facilities and especially clean air is severely compromised on some farms, mostly due to outdated facilities. The link between environmental quality, previous investment, and financial margins over the past 5 years is very clear on some farms.

·  A total of 26/40 (65%) farms used home-mixed feed, and 35/40 (87.5%) of farms used antibiotics / growth promoters in one or more rations.

·  Feed bins were routinely cleaned on 52% of farms, and never on 34% of farms. Farm feed mills were of a similar standard. Elevated concentrations of mycotoxins were found on farms with relevant health problems. It is suggested that the role of mycotoxins in the current health status of UK pigs should be examined, and that this would be facilitated by the development of new analytic techniques and/or more cost-effective analytical procedures.

·  There is substantial potential to improve water management and thereby support animal health; between 12 and 56% of drinkers (depending on housing type) did not give adequate flow rates, and less than 20% of water samples were below the recommended quality limit of 200 cfu/ml. Intervention farms responded positively to support information on water management.

·  Storage and hygiene related to use of medication is generally good. 90% of farms had a clear register of medicines and clear disposal policies. Good needle practice was most common in farrowing houses, and least good on dry sows.

·  Median veterinary and in-feed medication costs were £57 per sow per year in 2001, rising to £57 in 2002. Variation between farms was high, reflecting disease status (and especially impact of PMWS) and attitudes towards use of in-feed medication.

·  Diagnosis before treatment is underused. Reasons cited for lack of use include poor information transfer when it is used, lack of understanding of the number of samples required to give a valid result, and the inability to make a cost/benefit analysis because the real cost of disease is unknown in many cases.

·  Sick pig facilities were mostly good although shared air space with healthy cohorts was common. Whilst over half of farms kept ‘sick’ pigs separate through to slaughter, 31% of farms still return pigs to the main herd.

·  The quality of dead pig disposal facilities was highly variable, and includes practices that increase the risk of disease transmission. Introduction of strategies to reduce risk and support compliance with new EU legislation (Animal By-Products Regulation) will be of significant benefit to the industry.

·  Production data management is excellent on a few farms; these units are able to use data as a health management tool. 12.5% of farms were unable to supply relevant data even after 12 months and repeated contact. A further 3/40 farms (7.5%) required significant additional inputs to extract the required data, which implies that basic production parameters are not routinely examined on paper. There is an excellent opportunity for the industry to improve health and profitability through knowledge management; the suggested requirements are simplified software programmes and better training.

·  Information relevant to health management was supplied to the 20 intervention farms by use of standard operating procedures (SOPs) adapted from a database of generic SOPs produced by the University of Aberdeen

·  Attitudes to the SOPs was variable, although 63% and 27% respectively, agreed or strongly agreed that the industry needs to adopt SOPs to help improve health management. Responses included those that felt that SOPs required too much additional work, although most thought that the external support had assisted to identify weaknesses and formulate a strategy to manage health.

·  The project has linked to a study of antibiotic resistance that is using meta-population analysis of faecal samples.

·  Output from the project will be further defined in collaboration with the production sector and major stakeholders.