Laying hen

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A laying hen is a female domestic chicken that lays a particularly large number of eggs . Laying chickens are diligent forage seekers and good feed converters.

Originally, each hen that laid eggs for consumption was called "laying hen" to distinguish it from the " brood hen " or mother hen, a hen that incubates eggs or leads chicks. In chicken breeding there are three groups of farm chickens : laying chickens (for egg production), broiler chickens (for meat production) and dual-purpose chickens (for both egg and meat production).

Laying chickens

Today, the hybrid breeding method is mainly used to breed specialized chickens . Hybrid chickens that are specially bred and kept for egg production are called laying hybrids .

Breeds that were of economic importance until the end of the Second World War and whose genetic material was incorporated into the breeding of the laying hybrids are white Leghorn , partridge-colored Italians and Rhodian countries .

Weiß- and Braunleger

Today in the economically oriented egg production almost exclusively white and brown egg-laying hybrids, so-called white or brown layers , are used.

White layers produce white eggs, which are of a better quality compared to the brown eggs of the brown layers. There are fewer problems with the fish odor in the eggs, significantly fewer blood and meat stains and the egg white height, especially in the last laying section, is better. The chickens are lighter than brown layers and are characterized by lower feed consumption. They are suitable for a longer laying period and have a more pronounced nest instinct. There is less loss of cannibalism among whitefishers under the same housing conditions.

Brown-shell eggs are more popular with consumers, especially as free-range eggs. Brown laying eggs are usually heavier and they lay fewer unwanted small eggs. Due to their behavior and the original color of the plumage, the hens are generally well suited to being kept outdoors. They are calm, trusting and less frightened animals that fly less high.

In addition, “ Grün- ” and “ Rotleger ” are marketed for niche production . Green layers come from matings with Araucana cocks, red layers usually from cross breeding with Marans .

attitude

In 1950 a hen laid 120 eggs a year, compared to around 300 in 2015.

In Germany there were in companies with at least 3,000 hen keeping places on 1 December 2011. good 34 million laying hens, an increase of 13.8 percent compared to December 2010. The dominant form of entertainment in the German laying hen farms is the deep litter . Of the hen-keeping places available in Germany, 25.7 million places (64.2%) were free-range , 5.8 million places (14.4%) were free-range and 5.6 million places (14.0%) were kept in small groups Cages. Another 3.0 million places (7.4%) were in organic production. In 2018, 18 percent of laying hens in Switzerland were kept on organic farms.

Until the ban in Germany (January 1, 2009), laying hens were mainly kept in so-called battery cells (cages). Rules for keeping laying hens can be found in the Animal Welfare Farm Animal Husbandry Ordinance .

Induced moulting in egg production

In most modern egg production contexts, domestic chickens are kept in production cycles and regularly replaced with a new population if there are economic reasons to do so. To extend the production cycle of a population beyond a laying period, one induces a moult because chickens renew their reproductive organs during this process. The regular shedding and new growth of bird feathers is called moulting. With an induced moult, chickens can be used for one or two additional periods in industrial egg production with laying quantities that are often only slightly below the maximum values ​​of the first season. For the USA, it was estimated in 2003 that in 70% of the chicken population moulting is induced by food deprivation. Induction of moulting through deprivation of food or water is prohibited in the UK.

Industrial chicken farming: battery laying

From around the 1950s, the lighting, temperature and other environmental parameters, and thus the time of the moult, were controlled in larger hen houses. Historically, the moulting of chickens was induced by the onset of winter and the associated shortened daylight periods and other environmental stress . This led to rising market prices as eggs became scarce during this time. Therefore, chicken farmers had an interest in delaying the moulting of their chickens as long as possible in order to benefit from the high prices. In modern production contexts, there is no stress effect that would cause chickens to moult, which leads to a decrease in the number of eggs after about one laying season and to a poorer usability of the eggs.

In order to induce moulting, the population is left to starve for 7-14 days - in experiments up to 28 days. During this period the chickens lose about 30% of their body weight and feathers. According to educational literature, the death rate during moulting can ideally be kept at 1.25% in the one to two week period (the average death rate in commercial laying farms is 0.5–1% per month during a production cycle).

In addition to complete food deprivation, there is also the possibility of only giving certain food in order to induce moulting due to a lack of certain nutrients. The method in Morley A. Jull : Poultry Husbandry (1938 McGraw-Hill) is considered to be the first description of an induced moult .

Plaster and clay egg

With a deceptively real-looking egg made of plaster of paris or clay, hens are encouraged to put their egg in an offered nest and not hide it elsewhere, where it is difficult to reach or can hardly be found by the keeper.

If a hen chuckles, ie if she remains seated for incubation, a test can be carried out with several of these artificial eggs for 3–4 days to determine whether it remains more reliable during incubation, before fertilized eggs are pushed beneath it for 21 days to hatch. In Hilgert the small-scale production of clay eggs and other things from pipe clay was concentrated until 1990.

Life expectancy

The female chicks are raised in the commercial egg production for a period of approx. 18 weeks, after which they are housed in order to fulfill their function as laying hens. This lasts about 15 months until the laying performance decreases and they are slaughtered and sold as soup chickens. The male chicks are killed on the first day of life. They are raised at most with hybrid chicken species, increasingly due to growing customer demand for reasons of animal welfare. Laying hens in private hobby owners, which are kept similar to domestic animals, reach an age of around eight years, and the laying performance drops significantly after around four years.

Web links

Wiktionary: Laying hen  - explanations of meanings, word origins, synonyms, translations
Commons : Laying Hens  - Collection of images, videos and audio files

Individual evidence

  1. ↑ Laying hen. duden.de, accessed on January 25, 2020 .
  2. ↑ Bruno Dürigen : Poultry farming according to its current rational point of view. 2nd completely revised edition, Paul Parey, Berlin 1906. Wirtschaftshühner, p. 214 f. ( online at Hathi Trust, digital library)
  3. ↑ Laying hen. In: Jacob Grimm , Wilhelm Grimm (Hrsg.): German dictionary . tape 12 : L, M - (VI). S. Hirzel, Leipzig 1885, Sp. 518 ( woerterbuchnetz.de ).
  4. ↑ Brood hen. In: Jacob Grimm , Wilhelm Grimm (Hrsg.): German dictionary . tape 2 : Beer murderer – D - (II). S. Hirzel, Leipzig 1860, Sp. 456 ( woerterbuchnetz.de ).
  5. ↑ DK Flock, M. Schmutz, R. Preisinger: Practice-oriented laying hen breeding . In: Landbauforschung - vTI Agriculture and Forestry Research . Special issue 322, 2008, 3.3.1 Introduction, p. 70 ( literatur.ti.bund.de [PDF; accessed on April 5, 2014]).
  6. ↑ a b c Breeding and performance characteristics of hybrid animals . In: Aviforum (Ed.): Leaflets on poultry farming . December 1999, choice of laying hybrids, p. 6 ( Page no longer available , search in web archives: PDF document, 532 kB [accessed on March 29, 2014]).@1@ 2Template: Dead Link / www.blv.admin.ch
  7. ↑ Frank Allmer: Proud taps and hardworking hens (=  country life ). Cadmos Verlag, Brunsbek 2009, ISBN 978-3-86127-674-6 , Colorful eggs: Grünleger and Rotleger , p. 70-71 .
  8. ↑ New ways for more animal welfare , A magazine of the Federal Ministry of Food and Agriculture, 1st edition, January 2016, p. 7
  9. ↑ Federal Statistical Office: Hen rearing places and laying hens - Overall by husbandry type , accessed on November 22, 2012.
  10. ↑ Federal Statistical Office : Agricultural Structure Survey 2018 In: admin.ch , May 28, 2019, accessed on February 1, 2020.
  11. ↑ M. Yousaf, AS Chaudhry: History, changing scenarios and future strategies to induce moulting in laying hens. In: World's Poultry Science Journal. 64, 2008, pp. 65-75.
  12. ↑ DEFRA : laying hens - code of recommendations for the welfare of livestock (PDF; 108 kB)
  13. ^ AB Molino, EA Garcia, DA Berto, K. Pelícia, AP Silva, F. Vercese: The effects of alternative forced-molting methods on the performance and egg quality of commercial layers. In: Brazilian Journal of Poultry Science. 11, 2009, pp. 109-113.
  14. ^ AB Webster: Physiology and behavior of the hen during induced moult. In: Poultry Science. 82, 2003, pp. 992-1002.
  15. ^ Mack O. North, Donald D Bell: Commercial Chicken Production Manual. 4th edition. Van Nostrand Reinhold, 1990, p. 438.
  16. ↑ D. Patwardhan, A. King: Review: feed withdrawal and non feed withdrawal moult. In: World's Poultry Science Journal. 67, 2011, pp. 253-268.
  17. ↑ RU Khan, Z. Nikousefat, M. Javdani, V. Tufarelli, V. Laudadio: Zinc-induced moulting: production and physiology. In: World's Poultry Science Journal. 67, 2011, pp. 497-506. doi: 10.1017 / S0043933911000547 .
  18. ↑ Shooting gallery tubes and nesting eggs made of pipe clay. Hilgert / Westerwald 1990. UHD version Landschaftsverband Rheinland (LVR). Folklore film documentary, 1990. Digital Heritage Service GmbH, published March 3, 2019, youtube.com, accessed April 10, 2019. Video (29:29).
  19. ↑ When do chickens lay eggs? huehner-ratgeber.de, accessed April 9, 2019.
  20. ↑ The natural brood in domestic chickens (keeping chickens appropriate to the species - Part 4) lolaundlumpa.com, accessed April 9, 2019.
  21. ↑ When do plaster eggs go into the nest? Forum contributions from 2010, huehner-info.de, accessed April 9, 2019.