For the purposes of this specification, the term “animal” should be construed to include within its meaning sheep, cattle, goats, pigs, chickens, ostriches, reptiles and the like; the term “disease” should be construed to include within its meaning diarrhoea; the term “pathogen” should be construed to include within its meaning microorganisms such as E-coli; and the term “medicament” should be construed to include within its meaning oral bactericides and bactericidal inhalants. The applicant envisages that the invention will be applicable particularly, but not exclusively, in the preparation of a medicament for use in the treatment of pathogenic microorganisms in weaner piglets and chicklets.
It will be appreciated that in the commercial rearing of domestic livestock, notably in the pig and poultry industries, the growth performance of animals forms the basis of economic viability of an operation. A number of factors may influence such growth performance such as temperature, diet, stocking rates, general husbandry and notably the presence and level of harmful pathogenic microorganisms. The microorganisms may be abundant in the water, food and in air space in which the animals are housed. In general, all pathogenic microorganisms exert a deleterious effect on the animal to a greater or lesser degree. This depends on factors such as the number of microorganisms present, the pathogenicity of the strain and its resistance to anti-microbials utilized in its control, as well as the immune status of an individual animal to a specific microorganism at any particular stage.
Methods such as antimicrobial medication of feeding rations, water treatment and inoculations are commonly employed to reduce the severity of impact on the animal.
The efficacy of a chosen control measure, or combination of measures, is gauged in general by the percentage reduction in mortalities and the growth rate of survivors, taking into account the efficacy of growth (i.e. the amount of feed consumed per unit of growth). This is referred to as the feed conversion rate.
The current methods for the control of microorganisms is based on low level, and sometimes therapeutic, medication of feeding rations, as well as drinking water consumed by the animal. This practice has fallen out of favour in recent times due to the resistance being built up by microorganisms to antibiotics, as well as residue levels of such agents in meat consumed by people. The presence of antibiotic residues in food products leads to allergic and anaphylactic reactions in humans. The development of resistant strains of microorganisms makes anti-microbials ineffective. This method of disease control was recently banned in the European Union and other countries are following suit.