FEBRA2

This paper reports on the sales of veterinary antimicrobial products in the UK in 1999. It shows that there was a significant decline in the sales of antimicrobials between 1998 and 1999 and that sales in 1999 are the lowest of the past seven years for which figures are available. The sales of antimicrobials used as growth promoters declined from 89 tonnes of the base active ingredient in 1998 to 28 tonnes in 1999. During the same period a 12% drop in sales of those antimicrobials used in the treatment of food animals was also recorded (433 tonnes to 383 tonnes). The change was mainly in the sales of tetracyclines, which fell by 41 tonnes (18%) from 1998 to 1999. Overall there was a decrease of 19% (from 554 tonnes to 448 tonnes) in the total of antimicrobials sold for use in food and non-food animals.

Sales in food animals accounted for 92% (411 tonnes) of the annual sales of 448 tonnes. Just under half (47%) of the total sales of antimicrobials for use in food animals is accounted for by tetracyclines whereas fluoroquinolones account for about 1 tonne (0.3%).

Ninety three percent of the antimicrobials sold for use in food animals in 1999 were for therapeutic purposes, with growth promoters accounting for 7%. Approximately 80% of antimicrobial products are administered via feedstuffs most of which is used for pigs and poultry.

The decline in sales of antimicrobials in 1999 may be attributed to three factors: the EU ban on June 30 1999 of those growth promoters that confer cross-resistance to antimicrobials used in human medicine; the severe economic down turn affecting livestock farming leading to a decrease in production in the pig and poultry industries; and the response to the prudent and responsible use campaign, which started about 18 months ago.

Introduction

The emergence of antimicrobial resistance as a serious problem in human medicine has led to increasing concerns about the use of antimicrobial products in medicine, veterinary medicine, animal production, agriculture and horticulture. In the UK, the Government has made clear that it takes the problem of antimicrobial resistance very seriously and a comprehensive strategy has been developed to address the issue in order to maintain the effectiveness of antimicrobial products. A key element of this plan is the collection of information on the amounts of antimicrobial products used in veterinary medicine and animal production in the UK.

The Veterinary Medicines Directorate (VMD), an Executive Agency in the Ministry of Agriculture, Fisheries and Food is responsible for the authorisation of veterinary medicines in the UK and in May 2000 published sales figures of antimicrobials authorised as veterinary medicinal products, growth promoters or coccidiostats for the period 1993-98. The information was provided by the veterinary pharmaceutical companies marketing these products in the UK. The figures are being updated annually and this paper summarises the information provided for 1999.

Total Sales

Table 1 shows the amounts of therapeutic antimicrobials and antimicrobial growth promoters sold for use in food animals (including aquaculture) in 1998 and 1999 expressed as tonnes of base active ingredients. The table also includes the total sales of therapeutic antimicrobials sold for use in non-food animals (horses, dogs, cats etc.) and the total amounts of antimicrobials sold for use in food animals and non-food animals during this period.

Table 1 : Sales of antimicrobial therapeutic products and growth promoters (tonnes active ingredient) 1998 and 1999

Total antimicrobial sales in food animals and non-food animals fell by 19% from 554 tonnes in 1998 to 448 tonnes. Antimicrobials sold for growth promotion in food animals fell by 69% in 1999 and the proportion of antimicrobials used for growth promotion fell from 17% in 1998 to 7% in 1999. In contrast, the amounts sold for use in non-food animals increased from 32 tonnes to 37 tonnes due to an increase in sales of antimicrobial products used in horses.

The decrease in sales of antimicrobials in food animals may be due to three main factors. First the 69% decrease in antimicrobial growth promoters is likely to be due to the ban by the EU on June 30 1999 of those growth promoters that confer cross-resistance to antimicrobials used in human medicine. Secondly, 1999 saw a down turn in the farming industry, which led to considerable restructuring of the industry. During this period poultry production fell by 3%, while the pig industry suffered 8% loss in production. Thirdly the decline may also be in response to the prudent use campaign, which started about 18 months ago. The British Veterinary Association has published guidelines promoting responsible and prudent use of antimicrobials within the veterinary profession. Prudent use guidelines have also been published for each of the four major species (cattle, sheep, pigs, and poultry) by the Responsible Use of Medicines in Agriculture alliance (RUMA) aimed principally at farmers.

Although there are reports of illegal importation of veterinary medicinal products including antimicrobials, especially intramammary products, the impact on sales has been impossible to quantify.

Table 2 compares the sales of antimicrobials between 1993 and 1999. It shows that there was a significant rise in the sale of antimicrobials from 1993-1996, followed by a fall in 1997, which has continued through 1998 to 1999. The table also shows that by 1999, the sales of antimicrobials apart from in non-food animals has fallen below the levels sold in 1993.

Table 2 : Sales of antimicrobial therapeutic products and growth promoters (tonnes active ingredient) 1993-1999

* Horses, dogs, cats etc.

Sales by Antimicrobial Group

Table 3 shows the sales of various groups of antimicrobials in food animals in 1998 and 1999. In 1999, tetracyclines, trimethoprim/sulphonamides and ß-lactams (including penicillin) continued to account for most of the therapeutic antimicrobials sold for use in food animals. Together they contributed 85% with tetracyclines accounting for 50%, Trimethoprim/sulphonamides 21% and ß lactams 14%. Most of the tetracyclines were used in pigs and poultry in medicated feedingstuffs (MFS) to treat various disorders including respiratory disease.

Table 3 : Sales of antimicrobial therapeutic products (tonnes active ingredient) 1998 and 1999.

*Includes lincosamides, tiamulin, oxolinic acid

The table indicates that sales were down for all the major therapeutic groups during 1999 except trimethoprim/sulphonamides and macrolides. According to industry sources the increase might have been due to the high incidence of gastrointestinal problems in pigs following the ban of growth promoters. However, the most significant change is in the sales of tetracycline, which showed an 18%, decrease in 1999. There was no change in the sales of fluoroquinolones.

Table 4 summarises the 1999 sales of coccidiostats reported to the VMD. It has not been possible to obtain the full data, and whilst the total sales cannot be estimated, it is expected to be higher than 66 tonnes. Coccidiostats are not related to any antibiotic used in human therapy. They are used exclusively in animals to prevent coccidiosis, particularly in poultry.

Table 5 lists the major types of formulation of antimicrobials sold in 1999. Medicated feedstuffs made up 80% of the therapeutic antimicrobials, whilst water/oral medication and injectables contributed 10% and 7% respectively. Intramammary products and other therapeutic antimicrobial products contributed 1% each. Compared to the 1998 sales figures, there was an overall 12% decrease in sales, mainly from the 15% fall in the sales of medicated feedstuffs. Intramammaries also registered a 21% decrease at a time when dairy cattle numbers were increasing. Dry cow products fell from 3.9 tonnes active ingredient in 1998 to 3.2 tonnes in 1999. Lactating cow products followed a similar trend, falling from 2.8 tonnes in 1998 to 2.3 tonnes in 1999. In contrast water/oral products increased sales by 5% whilst injectables showed a 12% rise. The reasons for these increases may be similar to those reported for macrolides.

* includes aerosols, creams, ear and eye medications

Sales by Food Animal Species

Table 6 provides a breakdown of the sales of antimicrobials for use in different species of food animals. It is clear from this table that about 70% of antimicrobial products are authorised for use in more than one species.

It is likely that most are used in pigs and poultry but it is currently impossible to determine the exact usage in different species. An independent study is under way to provide further data on this aspect of the use of antimicrobials in food animals.

* a combination of two or more of the following species- cattle, pigs,         sheep and poultry

** does not include growth promoters all of which are multi-species

Table 6 shows that there was a further decline in 1999 in the sales of antimicrobials used in aquaculture at a time when fish production was increasing. In 1993, 55,000 tonnes of fish were produced and 10 tonnes of antimicrobials were sold. In 1999, 143,000 tonnes of fish were produced and 4 tonnes of antimicrobials sold. It has been suggested that the reduction in the sales of antimicrobials in aquaculture is due mainly to improved husbandry techniques and the use of increasingly effective vaccines.

Table 7 shows the live weights of animals slaughtered from 1993-1999 and the sales of antimicrobials during the same period. The total live weight of livestock slaughtered increased between 1993-1995, which corresponds to the trend in sales of antimicrobials during this period. The total live weight of livestock slaughtered declined in 1996, mainly due to the sharp decline in cattle slaughterings as a result of the BSE crisis but increased in the subsequent two years, before falling again in 1999.

*Source- Agriculture in the United Kingdom 1993-1999. Ministry of Agriculture, Fisheries and Food

Antimicrobial sales, on the other hand, reached a peak in 1996 before falling in the subsequent three years. Between 1998 and 1999 poultry recorded a 3% drop in production, the first fall in a long-running upward trend. Cattle and pig production fell by 2% and 8% respectively, whereas sheep increased by 5%, and fish registered a 13% increase in production. The total live weight of animals slaughtered fell by 2.5% between 1998 and 1999 whilst antimicrobial sales in food animals fell by 21%.

Many farm animals are reared to slaughter without the use of antimicrobials or growth promoters. However, if it were assumed that the antimicrobials sold for food animals were used in every animal slaughtered, 1 tonne of antimicrobial was used to produce 10,912 tonnes of live weight of animals slaughtered in 1998 and 13,516 tonnes in 1999.