Sexes
As sexing ( lat. Sexus "gender") generally means the identification and segregation of animals or sperm on the basis of sex , particularly in poultry farming. Determination of the sex of chicks in egg and poultry production facilities is known and sometimes controversial . For economic reasons, as a result of the determination, chicks with unwanted or unclear sexual characteristics are killed (so-called day - old chicks ).
In animal husbandry, e.g. B. in cattle, " sexed sperm " is used to ensure that only animals of a desired sex are conceived .
distribution
Sex determination is carried out in egg production because only hens lay eggs and are therefore relevant. Since the growth performance of chicken breeds bred for egg production is below that of poultry breeding, the chickens are killed.
In the broiler both female and male chicks are fattened. Since chicks selected by gender are more expensive due to the manual labor involved, so-called straight-run chicks are usually used in chicken fattening , in which the gender is not determined and where the gender distribution is balanced. Due to the high costs, only about 27% of the broiler chicks in the USA are selected by sex. On the other hand, chicks hatched for turkey fattening are always selected because there are sufficiently large differences between turkeys and turkeys in terms of growth rates, market maturity, management and nutrition to justify the higher costs economically .
Poultry farmers also sort chicks by sex, and the unwanted males and females are killed because breeding lines are separated by sex (father and mother lines).
Methods
In manufacturing companies, selection has so far only been done by hand. This is done directly by the human after hatching and requires some practice. A distinction must be made between the so-called cloak sex and spring sex .
Cloacal sex
In " cloaca sex", slight pressure is exerted on the cloaca , causing it to invert. The penis is larger, more curved, and more gnarled than the clitoris . Kloakensexen requires training , high dexterity and the ability to concentrate . With the appropriate experience, a person can select around 2000 chicks per hour with an error rate of 2%.
Spring sex
There are two types of pen sex; through color coding, which is mostly used today, and through length sex, where the length of the feather is decisive. The feather sex is caused by a crossable gene , which slows down the growth of a wing feather in male chicks. Differentiating between chickens and chickens is easier than cloak sex and cheaper because it doesn't require as well trained staff.
The gene is associated with an endogenous retrovirus . It has been found that chickens with this gene have an increased propensity for cannibalism in hot weather .
Disadvantages of manual sex after hatching result from the labor costs and time required. Sexing before hatching would be more beneficial for two other reasons: vaccinations could be carried out more cheaply and the ethically criticized killing of chicks could be reduced.
Jurisprudence
The Higher Administrative Court of Münster decided at the beginning of May 2016 that the killing of male day-old chicks due to egg production was a so-called reasonable reason according to Represents animal welfare law. The practice of shredding and gassing male chicks is therefore legal.
Research approaches
In order to avoid the disadvantages of manual selection, there are several approaches: After a system 13 to 17 days after oviposition be (4 to 8 days before hatching) differences in estrogen reflected in samples of allantoic fluid of male and female embryos detected. Another method is based on the higher RNA content of male embryos, which can be determined by Raman spectroscopy .
Web links
- B. Doyle: The Joy of Sexing. At: TheAtlantic.com. March 2000. Report about a sex man.
- Sexing Chicks After a Few Weeks. ( Memento from January 21, 2013 in the Internet Archive ) At: Ithaca.edu.
Individual evidence
- ↑ a b c d e P. Phelps: Gender identification of chicks prior to hatch. Fiftieth Annual National Breeders Roundtable Proceedings (PDF file; 488 kB). US Poultry & Egg Association, Tucker, GA 2001.
- ^ A b c J. Gillespie, F. Flanders: Modern Livestock and Poultry Production. Cengage Learning, 2009.
- ^ A b c C. Ricks, N. Mendu, P. Phelps: The Embryonated Egg: A Practical Target for Genetic Based Advances to Improve Poultry Production. In: Poultry Science. Vol. 82, 2003, pp. 931-938.
- ↑ LG Münster has no suspicion of a criminal offense: day-old chicks may be killed. In: Legal Tribune Online , March 9, 2016. Retrieved May 21, 2016.
- ↑ Gerald Steiner et al .: Sexing of turkey poults by Fourier transform infrared spectroscopy. Analytical Tools for the Nanoworld 396, 1, 2010, doi : 10.1007 / s00216-009-3273-z .
- ↑ Successful research on the exit from chick killing - prototype for sex determination in the egg by the end of 2016. At: Uni-Leipzig.de.
- ↑ Alternatives to killing male chicks. ( Memento of the original from June 30, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. At: BMEL.de. As of March 30, 2015.
