Farm animals such as chickens and pigs have been deliberately bred to grow bigger and faster than nature intended.
If breeding stock is fed concentrated feed and allowed to eat as much as their appetite demands, they may become too heavy to breed efficiently or to stay in good health. The industry prevents this by restricting the amount of feed given to the animals.
To prevent breeding stock of these modern breeds becoming overweight, breeder chickens and pigs endure feed restriction. The food offers all the nutrients they need but only part of the food volume. They suffer permanent hunger as a result.
The welfare-friendly solution would be to reverse the trend toward fast-growing breeds of animal. The other is to feed bulkier, fibrous foods rather than concentrates.
The Welfare of Farmed Animals (England) Regulations 2000 prohibit the worst cruelty inflicted on broiler chicken breeding /parent stock - so-called ‘skip-a-day’ feeding, a feed restriction regime whereby birds are fed every other day or even less frequently.

Feed restriction is practised on species bred for fast growth, where ad lib feeding of parent stock would lead to health problems associated with obesity, endanger the animals’ ability to breed successfully.

Broiler Chicken Breeders

The most extreme example of feed restriction is probably found in broiler chicken breeding stock. UK-reared breeders certainly suffer from hunger, but legislation exists to protect them from the worst excesses of feed restriction. Bred to be heavy/obese for the supermarket shelf, the parents would be unable to breed at a commercially acceptable level if fed ad lib. Some therefore argue that desperately hungry birds are being maintained in ‘good health’.

The welfare conundrum has been summed up thus: “I would like to begin this paper by proposing a new scientific name for broiler breeders: Gallus neglectedus*...In fact, broiler breeders are caught on the horns of a dilemma: the management practices that are essential to ensure good health and reproductive competence may also reduce other aspects of welfare.” JA Mench, Department of Poultry Science, Maryland Univ., USA1

*Neglected chicken

Why a special problem with the breeding stock?

Over the last four decades or so, the chicken industry has carried genetic selection to extremes, resulting in a cruel but little talked-about welfare problem for the breeders, or parent birds: hunger. Selection has been geared to achieving a bird which at six or seven weeks of age (unprocessed) weighs on average nearly 3kg; that is, twice the weight of a chicken of the same age thirty years ago. Some put this figure higher, at up to a four-fold increase.2 The genetically ‘improved’ bird yields a lot of profitable meat; the downside in welfare terms of this profitability is expressed in the many health problems associated with these grossly over-sized baby birds (at slaughter their vocalisation is still high-pitched and their eyes blue; in the natural state birds of six weeks would still shelter under the mother hen’s wings).

In its March 2000 Report on the Welfare of Chickens Kept for Meat Production (Broilers) the European Commission’s Scientific Committee on Animal Health and Animal Welfare commented: “As broiler growth rate increased through genetic selection, it became necessary to impose progressively more severe food restriction on parent stock (breeders) during rearing, in order to limit their body weight at sexual maturity. Food restriction continues in a more mild form throughout adulthood...most of the welfare issues that relate specifically to commercial broiler production are a direct consequence of genetic selection for faster and more efficient production of chickens meat, and associated changes in biology and behaviour.”

High Court Judge sums up cruelty

“My conclusion is that the practice of rearing breeders for appetite, that is to feel especially hungry, and then restricting their feed with the effect of keeping them hungry, is cruel. It is a well-planned device for profit at the expense of suffering of the birds.”
(Mr. Justice Bell, summing up in the McDonald libel case, The High Court, London, July 1997.)

Bred to be hungry - the well-planned device

“The selection of broilers for increased growth has resulted in an increase in appetite (Siegel and Wisman, 1966) by modulating both central and peripheral mechanisms of hunger regulation (Lacy, D.E. et al.,1985; Denbow, 1989). The increased food intake causes obesity, which must be controlled in broiler parent stock in order to maintain reproductive competence. This is typically accomplished by limiting the quantity of food provided. Food restriction is initiated when birds are 1-3 weeks of age, and results in a reduction in the body weight of adults to approximately 45-50% of that of ad libitum-fed birds.”3

Not only has the modern broiler’s brain been modified, to encourage it to eat voraciously, but the same breed of bird must be severely restricted if he or she is to survive a year of maturity, which must involve competent breeding. Ad libitum feeding of the modern adult broiler results in diseases such as egg peritonitis, conditions specifically associated with obesity (such as heart failure), the inability of males to mount females, and high mortality from assorted causes. Even on restricted feed, chronic and painful orthopaedic problems exist in male breeding stock.4


The basis of future generations - the Pedigree/Elite (or grandparent) stock

In the case of the “elite” stock, feed restriction is especially severe for a two to three week period (at around six weeks of age) when birds hitherto fed ad libitum are suddenly allowed as little as 25% of their previous intake.5 This is because the potential of pedigree/elite birds is first assessed at six weeks, following ad lib. feed intake (six weeks being the approximate slaughter age of today’s chicken destined for the supermarket etc.). Selection is then made, and unsuitable birds culled. The Farm Animal Welfare Council states that this severe feed control “would imply a potentially serious welfare problem” and suggests that the industry keeps the practice constantly under review, with the aim of limiting the numbers involved and halting the procedure earlier, “for instance at 35 days”6.

There is a wealth of scientific evidence to prove that breeding birds suffer from the hunger imposed on them as a result of the physical change imposed on the modern chicken. Studies in zoos of the chicken’s ancestor, the red jungle fowl, show that birds spend up to 61% of their days pecking and scratching around for food (Dawkins, 1989). We know that the broiler’s brain has been modified to exaggerate appetite; yet the unfortunate breeding birds may be fed once a day*, on limited rations which are consumed in minutes7, and doomed to spend the rest of the day carrying out stereotyped pecking at non-food objects, and in increased drinking. “Overdrinking is also a common problem in broiler breeders (Kostal et al., 1992), resulting in the need to restrict water intake as well as food intake in order to maintain litter quality.”8

Recent figures suggest that the broiler chicken industry continues to select for even heavier birds at slaughter age.9

* See later section of ‘skip-a-day’ feeding.

Broiler breeders and UK law

The Welfare of Farmed Animals (England) Regulations 2000 prohibit the worst cruelty inflicted on the breeding /parent stock - so-called ‘skip-a-day’ feeding, a regime whereby birds are fed every other day or even less frequently.

‘Skip-a-day’ feeding, practised in many parts of the world, is illegal in the UK. Schedule 1 (para 24) of the Regulations states: “All animals shall have access to feed at intervals appropriate to their physiological needs (and, in any case, at least once a day), except where a veterinary surgeon acting in the exercise of his profession otherwise directs.” Para 25 states: “All animals shall either have access to a suitable water supply and be provided with an adequate supply of fresh drinking water each day or be able to satisfy their fluid intake by other means.”

Major breeding companies favour skip-a-day regimes for breeding stock, regarding them as a way of ensuring a more even distribution of rations. They ignore the suffering, which is a consequence of acute hunger.

Their reasoning is that by giving twice the birds’ daily ration every other day, more food will be available at one time, and all birds will have a better chance of getting their ‘fair share’ of the feed. As stated, UK law prohibits skip-a-day feeding. However, a conversation in 2000 between FAWN and a spokesperson for a major UK breeding company suggested persistent enthusiasm for the system. Clearly, where legislation does not exist to curb this cruelty, the semi-starvation of parent stock is deemed a regime to promote.

Skipping several days...

The truly desperate hunger of birds exposed to ‘skip-a-day’ feeding was described by Prof. Joy Mench at the 1993 Fourth Symposium on Poultry Welfare held in Edinburgh. In the discussion following the delivery of her paper (see ref. 1) Prof. Mench stated that she knew of companies in the USA favouring skipping not merely one day, but several. She graphically described the ‘tap-tapping’ sound as birds peck at walls etc., in their frantic yet futile attempts to find food.

Hunger leads to painful suffering

The hunger experienced by adult breeders, whether fed daily or less often, results in serious welfare problems:

“Staphylococcal arthritis is caused by Staphylococcus aureus, which invades the tissue or bloodstream, following injury to the skin, especially the feet. Any environmental factor, which may result in skin injury, e.g. a sharp projection, wood splinters in litter, or birds suffering injury when rushing to the feeders where feed restriction is practised (in broiler breeders particularly) will result in an increased incidence of this condition.10

“At this time (twelve weeks of age) staphylococcal infection of the hock joint is an important condition (in broiler breeders) and can cause loss through culling. Treatment with broad-spectrum antibiotics is sometimes effective, but must be started early and continued for two or three weeks. This hock condition can be almost eliminated by floor feeding without a trough (Dutchman type) feeder, on which birds appear to damage themselves. Traumatic injury, often not visible, seems to set off the staphylococcal infection.”11

“In broiler breeding flocks, separate sex feeding is being widely adopted as a means of controlling bodyweight gain in male birds, with the object of improving fertility. In breeding pens, grids fitted to the feeding trough allow females to feed, but males, which have wider heads, cannot gain access... From 45 weeks of age, a proportion of female birds were observed to have swollen heads, but only in that group fed from troughs fitted with grids. At 60 weeks of age approximately 15 per cent of the birds from that group were affected...In this flock head swelling was judged to be of traumatic origin and a consequence of fitting grids of incorrect size to feeding troughs.”12

NB The mental suffering of the hungry male birds, unable to reach the females’ food, can only be imagined.

Floor scattering of feed is more humane, but does not answer the demand for single sex feeding, once mature birds are housed together.

Feed restriction is not limited to the poultry industry…

Pigs

Breeding sows are kept hungry throughout their pregnancies, being fed an amount which fails to fully satisfy hunger (roughly 60% of what they would eat if fed ad lib) For those housed indoors, the combination of a limited amount of feed, combined with the frustration of not being able to root around for food, equates, according to John Webster, Professor of Animal Husbandry, Dept. of Veterinary Science, University of Bristol to ‘severe frustration’:

“The sow outdoors that can root in the earth in the expectation of an occasional reward in the form of a worm or some such morsel will derive far greater satisfaction than the sow on concrete in an individual stall with no opportunity to work for any satisfactory reward.”

Animal Welfare, A Cool Eye Towards Eden, chapter 8, Blackwell Science, 1994

Solutions

The welfare-friendly solution to the suffering involved in restrictive feeding regimes would be to reverse the trend toward fast-growing breeds of animal. The other is to feed bulkier, fibrous foods that satisfy the animals’ appetite without encouraging obesity. However, this solution fails to address the root causes of the problem.

References

Mench, J.A., Dept of Poultry Science, University of Maryland, USA, 1993. “Problems Associated with Broiler Breeder Management”, Fourth European Symposium on Poultry Welfare, Edinburgh, UK.

Hocking, P. and Savory, J., “Welfare Implications of Food Restriction in Broiler Breeders”, Roslin Institute Annual Report, 1994/5, p. 42.

Mench, J.A., Dept of Poultry Science, University of Maryland, USA, 1993. “Problems Associated with Broiler Breeder Management”, Fourth European Symposium on Poultry Welfare, Edinburgh, UK.

Ibid

Farm Animal Welfare Council’s 1998 ‘Report on the Welfare of Broiler Breeders’, para. 66.

Ibid, para 67.

Hocking, P. and Savory, J., “Welfare Implications of Food Restriction in Broiler Breeders”, Roslin Institute Annual Report, 1994/5, p. 42.

Mench, J.A., Dept of Poultry Science, University of Maryland, USA, 1993. “Problems Associated with Broiler Breeder Management”, Fourth European Symposium on Poultry Welfare, Edinburgh, UK.

Year 2000 information from ADAS Gleadthorpe Research Centre

Coutts, G.S., BVMS, MRCVS, ‘Poultry Diseases Under Modern Management’, p. 53, Nimrod Press Ltd.

Pattison, Mark, MRCVS, ‘Poultry Practice’, Ed. Edward Boden, Bailliere Tindall, 1993, p.12.

Duff, S.R., et al., ‘Head Swelling of Traumatic Origin in Broiler Breeding Fowl, Veterinary Record, Vol. 125, No. 6.