Transport of chicks When broiler chicks are a day-old, they are transported in transport modules (or chick boxes) from the hatchery to the rearing farm. Chicks travel along a conveyor belt and are dropped into modules. During this process the chicks are immunised with a spray vaccination4 . It is currently not clear what the optimal conditions for transport of chicks are, as there is insufficient scientific knowledge. The debate focusses on maximum journey times as chicks are sustained by energy and water reserves from the yolk sac for a period of time after hatching5 . Housing systems for broiler chickens Intensive (industrial) farming systems Broilers used in intensive systems are of strains that have been bred to be very fast growing in order to gain weight quickly (with typical weight gains of over 50 g per day). Unlike laying hens (kept for egg production) which live for about a year, broilers only live for several weeks before they are slaughtered. In the EU, the slaughter age ranges from 21 to 170 days (typically around 5 to 7 weeks)6 . In the US - the average slaughter age is 47 days at a weight of 2.6kg7 In the EU – the average slaughter age is 42 days at a weight of 2.5kg8 Over the last 80 years or so, the slaughter age of a standard fast growing broiler has been decreasing, and market weight has increased (see Figure 1). In comparison, traditional meat chickens take around 12 weeks to reach slaughter weight9 . Figure 1. Market age and weight changes since 192510 Globally, over 70% of broilers chickens are raised in quite similar indoor intensive (industrial) farming systems11 and only a small proportion are reared in less intensive, higher welfare systems. Keeping broiler production indoors, without any access to outside areas can help with pest control. In temperate countries, broiler sheds are closed, climate-controlled (e.g. fan-ventilated) and have artificial lighting12 . In hotter countries, the sheds are more open so that the chickens are exposed to daylight and natural ventilation but have no outside access13 . The standard broiler shed in Europe is window-less, but in some countries (e.g. UK, The Netherlands), retailers or assurance schemes require windows to allow natural daylight14. In Sweden, windows to let in daylight are mandatory. The sheds are generally barren, except for feeding and drinking points. Broilers are reared on a littered floor (such as straw, wood shaving, peat, paper) to absorb the chickens’ excreta15. Feed is available at all times and Broiler chickens are transported twice in their lives, as day-old chicks (pictured) and as adults to the slaughterhouse. Farm Animal Welfare Compendium Updated 01.05.2013 Page 3 of 8 A typical chicken shed with tens of thousands birds. The red line provides water; the yellow circular structures are feeders. Higher welfare indoor includes perches, bails of straw to improve foraging and natural light. consists of a high protein feed, usually delivered via an automated feeding system. Some farms will feed ‘whole grains’, not processed cereals, as part of the diet16 . Broiler chicks are placed in the rearing sheds at one-day old and are kept in large, mixed-sex flocks. These flocks can consist of 10,000 to 20,000 birds, or more, in a single house17 . Broilers stay at the rearing farm until they reach slaughter age. When this point comes nearer, flocks are often thinned (not practiced in the US). This involves the catching and removal of a portion of the flock (usually the female birds that are lighter) for slaughter, to allow the remaining birds more room to grow on to a greater weight. The birds remaining in the house are likely to be stressed as a result of the thinning process, making them more susceptible to bacterial infections like Campylobacter, a cause of food poisoning which poses a public health concern18 . The litter in a broiler shed is usually not cleaned out during the birds’ lifetime (but completely removed after each batch, and the house cleaned and disinfected). The quality of the litter will influence air quality (i.e. dust levels, air humidity and ammonia levels). Litter can become wet depending on the type of litter material, the type of drinkers, water spillage and diet composition (influencing the composition of the bird’s faeces)19. Wet litter is a major risk factor for contact dermatitis (lesions of the breast, hocks and feet)20 . There is an EU Directive 2007/43/EC that specifies rules for the protection of chickens kept for meat production21 providing the minimal standards required to rear broilers. It outlines stocking densities, and atmospheric conditions, aiming to reduce extreme overcrowding and poor conditions. In countries within the EU, such as the UK, permitted stocking density is further restricted. In countries, such as the US (federal law), there are no laws on the stocking density limit. In very hot countries such as Brazil, stocking density may be reduced to allow for the warmer climate22 . Higher welfare (alternative) systems Chickens in alternative farming systems will have more space (lower stocking densities) and are often from slower growing breeds, slaughtered at an older age than fast growing breeds. The environment can also be enhanced, for example with indoor enrichment and/or with an outdoor area. In the EU, only a small proportion of commercial broilers are reared in alternative systems. In the USA, less than 1% of chickens are raised as ‘free-range’ (the term is used if chickens have access to the outdoors for at least some part of the day)23 . Hi
