Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Biotechnology in animal breeding.
Transcript of Biotechnology in animal breeding.
Biotechnology in animal breeding
Stages of Cloning
1) Involved in the process is a donor cell, which is the egg cell and somatic cell, which contains the desired DNA.
2) The egg cell’s nucleus is removed with a pipette, which is called enucleation.
3) This is also done to the somatic cell, which has the desired DNA. The nucleus from the somatic cell is transferred to the enucleated egg.
4) To jump start the fertilisation process, the new cell is electrocuted briefly.
5) Lastly, the new cell is implanted into the female surrogate for the rest of the pregnancy.
Fig.1 A diagram showing the process of Somatic Cell Nuclear Transfer (Taylor, 2009)
How cloning is used in the industry
How transgenics is used in the industry
Transgenesis is the process where additional genes are added into an organisms normal gene count (Klug and Cummings, 2003). The foreign genes are then expressed by the test subject’s offspring (Houdebine, 2003). Some of these test subjects are deliberately bred with genetic a defect, which decreases their quality of life. For instance, mice have been genetically modified to develop cancer (BBC, 2013).
There are three different methods of gene transfer, which are carried out through: retroviral vectors, Microinjection and embryonic stem cells (Fletcher et al, 2007).
Ethical and Welfare issues
Effectiveness of cloning and transgenics compared to other biotechnology methods
Fig.2 A simplified method of transgenisis in rats (FELASA, 1995)
Embryonic Stem Cell
Next, is the method of microinjection, which involves DNA being injected into a fertilised embryo under a microscope (Fletcher et al, 2007).
Firstly, a retroviral vector is a method where a cell in its early embryo stage can be infected before implantation (Fletcher et al, 2007). Once this cell has been infected, it is then transferred into a pesuodpregnant female the infection is not seen as foreign to the body, due to having the host cell as protection (Fletcher et al, 2007).
Cloning has not yet been approved for industrial use; however there are many ideas of ways in which it can be applied which would benefit humans (Homo sapiens).
Cloning can increase meat yield, specifically with beef cattle, replicating the double muscling gene giving offspring the ability to have oversized muscles (CIWF, 2010).
Disadvantages which arise are individuals having leg disorders and cows having calving problems, resulting in calves being delivered by caesarean section (CIWF, 2010).
However, some test subjects are bred for desirable characteristics; for example, pigs are bred with an additional growth hormone, which increases their body mass quicker than natural means (Rexroad, 1994).
Disadvantages of Trangenics
Fig. 3 DNA being added to a nucleus by the process of microinjection
(University of California, 2011)
Fig.4 Genetically Modified Pig, (science group, 1989)
Lastly, there is the use of embryonic stem cells. This encompasses the use of embryonic stem cells to create the transgenic animal. Stem cells are taken from the embryo; the gene is then inserted into the cells and placed into the host embryo (Margawati, 2003).
Biotechnology is the development of new processes for human and animal diseases and has become particularly useful in improving the fertility of certain species (Smith, 2004). Some examples of biotechnology are cloning and transgenics.
Fig 5. An example of a beef cattle with oversized muscles (Shirley, 2009).
Fig 6. Comparing the size of a transgenic salmon with a normal sized salmon (Oke et al., 2013)
Video 2 -Embryonic Stem Cell Animation
The view point of organisations and the public on cloning and transgenics
>There are major public concerns over biodiversity, farming methods and patenting due to a lack of full public understanding (Bulfield, 2000)
> As cloning involves reproducing offspring with specific traits, the genetic diversity is therefore decreased (Robinson, 2005). If cloning becomes more common, this will become a huge issue, as lack of genetic diversity in populations, increases the likelihood of environmental stress and decreases immunity to disease (Robinson, 2005).
> Transgenics is frowned upon by religion due to the belief God created the world and all the organisms on it, therefore genetics should not be modified to benefit any other species such as ourselves (BBC, 2013).
> Transgenics has been heavily used in the farm industry to help to create animals that grow faster. Whilst this has helped to reduce costs, there is little understanding of the impact of transgenic meat on humans, as research has yet to prove what futher genes expressions may be effected (Rexroad et al, 2007).
Ethical and Welfare Positives
It is believed however, that there will be some positive impacts on animal welfare with the advancement of cloning and transgenics (Houdebine, 2002).
It is understood that it will improve disease resistance, digestion, growth and fertility, however until further research is undertaken this cannot be proven (Houdebine, 2002).
>An additional issue is that the likelihood of success is very low. In the experiment involving Dolly the sheep, there was only one successful live birth, out of 277 attempts (Mepham, 2005). This could be seen as a huge wastage of life, as there were multiple foetuses, embryos and mature animals that died as part of this experiment (Mepham, 2005).
>Within animal science the three R's must be carried out, these are: reduce the number of animals, refine practices to decrease pain and distress and to replace animals with alternative techniques (Ormandy et al., 2011). Transgenic practices fail to achieve all three R's as more animals are being tested changing there genetic information along with the uncertainty of the animals experiencing pain and distress through the process and in the long run (Ormandy et al., 2011).
Due to the high number of concerns from both the public and wider organisations, the government set up the Banner Committee in 1995 to examine some of the issues raised by organisations such as the farm animal welfare council (Bulfield, 1997).
The committee established clear guidelines that should be adhered to when carrying out research into cloning and transgenics and asked that a further committee be set up to continually regulate the industry (Rexroad et al, 2007).
Transgenics is yet to be carried out in the industry as it is not believed to be suitable for human consumption, due to the uncertainty with regard to long term side effects.
Transgenics have been used for the production of farmed salmon. They allow the salmon to grow to full size in half the time of ordinarily farmed salmon (Aquabounty, 2013). However concerns have been raised that transgenic salmon have the ability to breed with wild fish, therefore making it very difficult to maintain high levels of traceability within the food chain (BBC, 2012).
Transgenics is also being used in the production of milk by dairy farmers. It has been suggested that the modification of the proteins in milk produced by cattle could benefit infants, increase product quality and increase milk production (Rexroad, 1994). However increased milk production has been linked to higher rates of mortality due to decreased health, leading to increased costs for farmers (CIWF, 2008).
Fig 7. Milk produced from transgenic cows (University of Waikato, 2013)
Cloning is also being explored in the area of xenotransplantation. It has been suggested that organs from pigs could be could be used for organ transplantation in humans (Klymiuk, 2010). This is due to the high similarity between pig and human organ structure and size (Klymuik, 2010).
However the use of pigs for human benefit is highly controversial with many animal rights organisations questioning whether this practice is ethical and whether the welfare of the animals used is being properly considered (Vajta and Gjerris, 2005).
Scientists are currently exploring whether the genes could be modified to remove the marker protein on the cells of the pig organs to remove the risk of rejection in human patients (Klymuik, 2010).
One reason why the effectiveness off cloning is limited is because; the offspring which has been cloned will experience different selective pressures and environmental changes. This could result in the offspring being different in character compared to the original individual the offspring was cloned from (Vleck, 1999). This unreliability also applies to Transgenesis, as even if the perfect phenotype is selected, it still does not mean that the offspring will be born the same. This could be because the traits are specific to a gender, or other traits will manifest after the selection phase (Clark and Whitelaw, 2003).
Nevertheless, improvements still need to be carried out on all biotchnology methods due to not being 100% successful, the environment and management of these biotechnologies need to be considered to achieve benefiting results (Wheeler and Campion, 2013).
Microinjection has less than a 2% success rate on transgenic individuals being produced this is due to the random insertion of genetic information with the uncertainty of the desired DNA attaching to the chromosomes (Murray and Anderson, 2000).
Fig 1. Taylor (2009) A diagram showing the process of Somatic Cell Nuclear Transfer Availible at: www.marymeetsdolly.com [Date Accessed: 6/10/2013]
. FELASA (1995) A Simplified method of Transgenisis in Rats, Available At :http://www.embracinganimal.com/transrats.html
[Date Accessed: 26/10/13]
. University of California (2011) DNA being added to a nucleus by the process of microinjection
Available At: http://www.research.uci.edu/tmf/dnaMicro.htm [Date Accessed: 26/10/2013]
Artificial insemination and selective breeding do have many positive features. Cows have very complex DNA and it is believed that of the 22000 genes in a cow, only 5 percent are controlled by humans (Strauss, 2009). It is not yet known how moving genes from one animal to another will effect them in the long run, therefore, until science has further advanced, traditional methods of breeding are more reliable (Strauss, 2009). Furthermore, through genetically engineering for some traits, it could inadvertently change other traits (Strauss, 2009). It has however been argued that the use of transgenics has reduced the length of time it takes to produce an improved market quality animal to 5 years (Strauss, 2009).
. Oke, K.B, Westley, P.A.H, Moreau, D.T.R and Fleming, I.A (2013) Comparing the size of a transgenic salmon with a normal sized salmon
Available At: http://gmoevidence.com/royal-society-scientists-warn-gm-salmon-can-breed-with-wild-trout/
[Date Accessed: 29/10/2013]
Aquabounty Technologies (2013) AquAdvantage Fish. Available at: http://www.aquabounty.com/products/products-295.aspx
BBC (2013), Biotechnology
Date Accessed: 30/10/13
Bullfield, G. (2000) “Farm Animal Biotechnology” Tibtech, 18, 10-13
Bulfield, G. (1997) Cloning in context http://www.timeshighereducation.co.uk/news/cloning-in-context/104599.article
Date Accessed: 3/11/13
Clark, J and Whitelaw, B. (2004). A future for transgenic livestock. Nature Reviews, Genetics. 4 (1), p825-833.
Compassion in world farming (2008) " The impact of selection for high milk yield on the health and welfare of dairy cattle" Available at www.ciwf.og/includes/documents/cm_docs/2010/impact_of_selection_on_health_and_welfare_of_dairy_cattle_2008.pdf. Accessed on 09/11/2013
Fletcher, H., Hickey, I. and Winter, P. (2007) Genetics, Taylor & Francis Group, Oxon
Houdebine, L.M (2003), Animal Transgenesis and Cloning, John Wiley & Sons Ltd, West Sussex
Houdebine, L.M (2002) “Transgenesis to improve animal production” Livestock Production Science 74 255-268
. Science Group (1989) Genetically modified Pig.
Available at http://www.sciencegroup.org.uk/ifgene/history.htm
[Date Accessed: 03/11/2013]
. Shirley, J (2009) An example of a beef cattle with oversized muscles.
Available at: http://www.independant.ie/business/farming/why-belgian-beef-is-all-about-blue-26556002.html
[Date Accessed: 03/11/2013]
. The University of Waikato (2013) Milk produced by transgenic cows. Available at: http://www.biotechlearn.org.nz/focus_stories/transgenic_cows/transgenic_cows_making_modified_milk
[Date Accessed: 09/11/201]
Cloning is carried out through non-sexual reproduction, where the genotype is not altered (Houdebine, 2003). Cloning takes place naturally through the replication of somatic cells and bacterial reproduction however, Somatic cell nuclear transfer can now be carried out to create an exact replica of an organism (Houdebine, 2003, The University of Utah, 2013).
Video 1- Process of cloning
Video 1 -
paowluk, date uploaded: 14th Dec 2007, Biology- nuclear transfer (clone creating), Youtube
Available At: youtube.com/watch?v=hepoJgGJtNc
[Date Accessed: 30/10/2013]
Video 2 -
Witf, date uploaded: 27th March 2009, Embryonic stem cell animation, Youtube
Available At: youtube.com/watch?v=-FfO_3xyrmU
[Date Accessed: 30/10/2013]
Video 3 -
NationalGeographic, date uploaded: 13th Feb 2008, Meet the super cow, Youtube
Available At: youtube.com/watch?v=Nmkj5gq1cQU
[Date Accessed: 09/11/2013]
Video 3 comparing biotchnologies
Institute for Laboratory Animal Research (1994) "Transgenic Farm Animals" Ilar Journal, 36 (1) 5-9.
Klug, W.S and Cummings, M.R (2003), Concepts of Genetics, Pearson Education, inc, New Jersey
Klymiuk, N (2010) "Genetic modification of pigs as organ donors for xenotransplantation." Available at ncbi.nlm.nih.gov. Accessed on 09/11/2013.
Margawati, E.T (2003) Transgenic Animals: Their Benefits to Human Welfare
Available at: www.actionbioscience.org/biotechnology/margawati.html
Date Accessed: 30/10/13
Mepham, B.T (2005) Bioethics: An introduction for the Biosciences, Oxford University Press, Oxford
Murray, J.D and Anderson, G.B (2000) “Genetic engineering and cloning may improve milk, livestock production.” California Agriculture, 54, 57-65.
Ormandy, E.H, Dale, J. and Griffin, G. (2011) “Genetic engineering of animals: Ethical issues, including welfare concerns.” Canadian Veterinary Journal, 52, 544-550
Rexroad, C.E (1994) “Transgenic Farm Animals.” ILAR Journal, 36, 5-9 University of Utah (2013). What is Cloning? Available at: http://learn.genetics.utah.edu/content/tech/cloning/whatiscloning/ Date Accessed: 26/10/13
Rexroad, C.E. Green, R.D. and Wall, R.J. (2007) Regulation of animal biotechnology: Research needs Theriogenology 68S (2007) S3-S8.
Robinson, T.R. (2005) "Genetics for Dummies" Wiley Publishing Inc. New Jersey, USA.
Smith, J.E (2004) Biotechnology, Cambridge University Press, Cambridge.
Vleck, L.D.V. (1999). Implications of cloning for breed improvement strategies: are traditional methods of animal improvement obsolete? Journal of Animal Science, 77 (1), p111-121.
Wheeler, M.B and Campion, D.R (2013) Animal Production- a longstanding biotechnological success
Available At: http://ajcn.nutrition.org/content/58/2/276S.full.pdf
[Date Accessed: 09th October 2013]