B&G

Description-

Somatic Cell Nuclear Transfer (SCNT) is a technique for cloning, this laboratory technique creates an ovum with a donor nucleus. Somatic cell nuclear transfer, also referred to as SCNT, in mammals is an aided reproductive technique which is used to produce an animal from a single cell nucleus using an nucleated oocyte as a recipient (Ogura, 2013). Using this cloning technique on mammalians has been successful on 23 species, including; cats, cattle, sheep, pigs, mice, rats and dogs (Zhang, 2018).

To complete SCNT, a somatic cell of an animal to be cloned is removed from the tissue and the nucleus is extracted. The nucleus of an egg cell is recovered from a surrogate and that nucleus is removed and the nucleus of the donor replaces it. This egg is then grown after being stimulated with a shock. The zygote now mitotically divides until blastocyst stage, where it is then inserted into the surrogate (Ogura, 2013).

Figure 1. Video coverage of how SCNT works (Ogura, 2013).

Cloning of non-human primates by SCNT has failed to generate live offspring so far, this is due to inappropriate programming for the somatic nucleus in supporting the transplanted embryos. However, has subsequently been evolving as a much simpler alternative to the classical micromanipulator-based SCNT (Manik, 2018).ar transfer is a technique for cloning, this laboratory technique creates an ovum with a donor nucleus. Somatic cell nuclear transfer, also referred to as SCNT, in mammals is an aided reproductive technique which is used to produce an animal from a single cell nucleus using an nucleated oocyte as a recipient (Ogura, 2013). Using this cloning technique on mammalians has been successful on 23 species, including; cats, cattle, sheep, pigs, mice, rats and dogs (Zhang, 2018).

To complete SCNT, a somatic cell of an animal to be cloned is removed from the tissue and the nucleus is extracted. The nucleus of an egg cell is recovered from a surrogate and that nucleus is removed and the nucleus of the donor replaces it. This egg is then grown after being stimulated with a shock. The zygote now mitotically divides until blastocyst stage, where it is then inserted into the surrogate (Ogura, 2013).

Cloning of non-human primates by SCNT has failed to generate live offspring so far, this is due to inappropriate programming for the somatic nucleus in supporting the transplanted embryos. However, has subsequently been evolving as a much simpler alternative to the classical micromanipulator-based SCNT (Manik, 2018).

Use Within Industry-

Somatic cloning allows for a many copies to be made from what can be considered a ‘genetically superior’ animal; this can have different uses in many industries. Agricultural industries have a use for cloning, the ability to identically copy the genetic make-up of an animal with desired characteristics means that they can create an ideal group (Edwards, et al., 2003). This also can reduce the demand for antibiotics and cut the costs of vets as the strains of diseases can be removed and prevented (FAWC, 2012). Creating an ideal group of animals in the agricultural industry ensures efficiency, which is especially important with the rising demand of animal produce (FAWC, 2012).

SCNT cloning can be used within conservation programmes to help preserve endangered animals, ensuring they do not go extinct (Liu , et al., 2018). Finally, cloning can allow for more successful xenotransplantation as it creates generally healthier organs and tissues to be used across species. A recent example of xenotransplantation from pigs to humans has showed the importance of cloning within the industry; five piglets were cloned from an adult female pig with the intention of xenotransplantation, which is a massive step towards the success of pig cloning (Dobson, 2000).

Effectiveness-

Fertile offspring are the most significant not objective by cloning laboratories for SCNT; for this extensive process to be successful, events must occur correctly (Atsuo Ogura, 2013). This method of cloning is often thought to be somewhat inefficient due to an extensive range of measurements which have to be taken into account to calculate efficiency (Stocum, 2016); such as the % of clones that cleave, undergo impaction and establish a successful pregnancy (Kristin M. Whitworth, 2010). The University of Missouri Research Centre concluded during 2010 that for SCNT to be successful, the nucleus derived from the donor, must be remodelled to resemble the nucleus of a zygote; this is thought to result in a change of the pattern of the genes which undergo transcription (Kristin M. Whitworth, 2010). In order for nuclear cloning to be efficient, additional protocols must be developed to assist the restructuring which is necessary for normal development of the clone (Kristin M. Whitworth, 2010).

Ethics and Welfare

Cloning is being investigated to be used to bring back extinct animals; however, it could be argued that due to survival of the fittest theories this would be unethical as they would not be adapted to survive within a developed environment. (Savulescu & Powell, 2013). The donor female needs to be induced to super ovulate to create more eggs, this is done through intraperitoneal or subcutaneous injections of hormones (Fenwick, et al., 2009). Once the offspring are born, they need to be genotyped which is completed by taking tissue samples, which is carried out by taking tail biopsies and ear notching (Elisabeth H, et al., 2011). Females are also required to be put under anaesthetic regularly for the blastocyst to be inserted; referring to welfare protocols, cloning is rather invasive technique and also unnatural on all parts. According to CCACs annual data, the increase of procedures that are seen to cause moderate to severe pain and distress are growing rapidly (Canadian Council on Animal Care, 1997).

Figure 2. This table depicts the advantages and disadvantes between SCNT and Nuclear Reprogramming (Savulescu & Powell, 2013).

Description

Figure 4. Video coverage depicting the purpose and process of Artificial Insemination.

Artificial Insemination (AI), is the biological introduction of semen into the vagina or cervix of a female, avoiding sexual intercourse (Vishwanath, 2003). There are numerous types of AI, although they all commence with a male sperm sample, the process is then timed with the female’s ovulation. The most common method is simply insertion of the semen into the vagina, closest to the cervix as possible (Vishwanath, 2003). Another successful method of AI is Intrauterine Insemination (IUI); this method involves inserting the sperm sample directly into the uterus, through the cervix (Howard, 1992) . AI procedures are extensively used with animal breeders when males may become sterile or when certain animals may suffer from prolonged infertility (Britannica, 2016).

Use Within Industry-

Figure 5. This image shows the impact of the use of AI within dairy cattle farms in the US (Brackett, 2009).

Industries tend to use AI to avoid natural mating between animals as this can have benefits such as, increased safety for the animal and the keeper, increased efficiency of production and better genetics (Stell, 2017).

Using AI allows industries to choose what genetics and characteristics are desirable in an animal; for example, meat production in cattle. Breeding cattle with low weight wouldn’t be worth as much income as selected sperm samples, such selecting genetically superior samples (Funk, 2006).

Another major advantage that AI brings to industries is the control of diseases, especially venereal diseases (Brackett, 2009).

Effectiveness-

AI is generally more effective than natural mating as a single male’s ejaculation can be diluted and used to inseminate hundreds of females instead of just one (Animal Smart, 2016). Therefore, a male can inseminate roughly 50,000 females in year through AI instead of only 40-50 through natural mating. Also, AI means that the semen can be analysed, and genes can be chosen to inseminate the females with. These genes can be more desirable to owners and allow them to increase the gene pool which could potentially decrease any effects of inbreeding (Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, 2018). AI also reduces any chances of injuries related to natural mating it the male and female are different sizes and the diseases involved through natural conception.

One of the first successful inseminations through AI was performed by Lazzaro Spallanzani during 1780, this occurred during an investigation into animal reproduction when he developed a technique to artificially inseminate dogs (Spallanzani, 1999).

AI also reduces any chances of injuries related to natural mating it the male and female are different sizes and the diseases involved through natural conception.

One of the first successful inseminations through AI was performed by Lazzaro Spallanzani during 1780, this occurred during an investigation into animal reproduction when he developed a technique to artificially inseminate dogs (Spallanzani, 1999).

Ehtics and Welfare-

Although still being proven with further studies, there is significant not evidence to suggest that behavioural traits can be influenced through the use of AI. For example, pigs used within the systems have had higher links with tail biting, which leads to big impactions on the welfare standards of the animal (Gamborg & Sandoe, 2003). These behaviours occur as it can be hard within breeding programmes to ensure welfare outweighs economic benefits (Gamborg & Sandoe, 2003). This ties in with ethical worries as concerns land upon the housing systems of these animals and whether or not they allow for ‘normal’ behaviours to be elicited, and if these issues lead to the spread of disease. This is specifically prominent within farmed species (Gamborg & Sandoe, 2003).

Some contrasting ethical views suggest that artificial insemination interferes with nature and the process is ‘playing god’ (Gong , et al., 2009). It opposes the theory of natural selection within species as you change and influence the future (Gamborg & Sandoe, 2003).

Figure 6. Image shows an inseminating needle inserting into the embryo, outside of the womb(Gamborg & Sandoe, 2003).

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Available at: http://theconversation.com/20-years-after-dolly-everything-you-always-wanted-to-know-about-the-cloned-sheep-and-what-came-next-72655

Brackett, B., 2009. new technologies in animal breeding. 1st ed. s.l.:s.n.

Britannica, T. E. o. E., 2016. Encyclopædia Britannica. [Online]

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[Accessed 7th February 2020].

Canadian Council on Animal Care, 1997. Guidelines on: transgenic animals, s.l.: s.n.

Dobson, R., 2000. Cloning of pigs bring xenotransplants closer. US National Library of Medicine , 320(7238), p. 826.

Easy, C., 2019. Conceive Easy. [Online]

Available at: https://www.conceiveeasy.com/get-pregnant/when-and-how-often-to-have-sex-to-get-pregnant/

[Accessed 7th February 2020].

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Elisabeth H, O., Dale, J. & Griffin, G., 2011. Genetic engineering of animals: Ethical issues, including welfare concerns. The Canadian Veterinary Journal, 52(5), pp. 544-550.

FAWC, 2012. Opinion on the Welfare Implications of Breeding and Breeding Technologies in Commercial Livestock Agriculture , London: Farm Animal Welfare Committee .

Fenwick, N., Griffin, G. & Gauthier, C., 2009. The welfare of animals used in science: How the “Three Rs” ethic guides improvements. The Canadian Veterinary Journal, 50(5), pp. 523-530.

Funk, D., 2006. Major Advances in Globalization and Consolidation of the Artificial Insemination Industry, 89(4), pp. 1362-1368.

Gamborg, C. & Sandoe, P., 2003. Breeding and biotechnology in farm animals – ethical issues1, London and New York: Univeristy of Copenhagen .

Gong , D. et al., 2009. An overview on ethical issues about sperm donation. Asian Journal of Andrology , 11(6), pp. 645-652.

Howard, J., 1992. SUCCESSFUL INDUCTION OF OVARIAN ACTIVITY AND LAPAROSCOPIC INTRAUTERINE ARTIFICIAL INSEMINATION IN THE CHEETAH (A CINONYX JUBA TUS). Journal of Zoo and Wildlife Medicine , 23(3rd), pp. 288-300.

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Kristin M. Whitworth, R. S. P., 2010. Somatic Cell Nuclear Transfer Efficiency: How Can It Be ImprovedThroughNuclearRemodelingandReprogramming?. Molecular Reproduction & Development, 77(1st), pp. 1001-1015.

Liu , Z. et al., 2018. Cloning of Macaque Monkeys by Somatic Cell Nuclear Transfer. Cell Press, 172(

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