16. The following sub-paragraphs list the most significant changes which have occurred in turkey production since the industry's establishment. These have not necessarily had improved welfare as an objective and are included primarily to illustrate the present nature of the industry:-
- (i) Genetics: Stock has been selected for faster growth rate, more efficient food conversion and a higher proportion of lean white breast meat. Turkey breeding companies operating from the UK have achieved an important position in the European market, as well as having a substantial market share in the USA.
- (ii) Nutrition: Knowledge of the nutrient requirements of turkeys has advanced and diets to exploit the genetic potential for rapid growth can be formulated with great precision. Turkeys produced for meat now grow faster because of these nutritional developments. Different feeding strategies are employed within the industry to control the nutrient intake of breeder flocks. These management techniques usually involve limiting the availability of feed, especially to the older males. Their intention is to slow down growth rate, thus reducing the likelihood of leg disorders, and to maximise breeder fecundity.
- (iii) Growth promoters: There has been increased use of so-called feed antibiotics which are not given for therapeutic purposes. They improve gut flora and increase nutrient absorption.
- (iv) Health: Most serious infectious diseases of turkeys may now be controlled by the use of live and killed vaccines, good site hygiene and therapeutic measures, so that the health of the national flock continues to improve (but see paragraphs 96-99). However, the geographical isolation of turkey growing farms remains an important means of limiting the spread of disease.
- (v) Environment: Controlled-environment housing now operates with greater precision since the ventilation requirements of the stock are better understood. Approximately 90% of the birds produced in this country are in large flocks on commercial sites which require precise control of temperature and ventilation rates.
- (vi) Equipment: Feeding and drinking systems have been increasingly mechanised in order to improve efficiency and to ensure that birds receive adequate fresh feed and water.
- (vii) Alternative systems: Increased interest has been shown in free-range turkey production. There are definitive marketing standards for alternative systems of production, which are described in EC Regulation 1538/91 on marketing standards for poultry. However, these relate to labelling terms rather than welfare standards.
- (viii) Stocking density: Several factors have led to an increase in the stocking density of turkeys kept in controlled-environment houses. These include changes in the market for turkey meat that have resulted in turkeys being grown to greater liveweights and improvements in the design of the ventilation systems serving the houses within which they are kept.
- (ix) Beak-trimming: The majority of turkeys are no longer beak-trimmed. However, in most cases where birds are kept in natural daylight (e.g. breeding stock and seasonal production in pole barns), the beaks are usually trimmed when the birds are only a few days old.