Genetic Improvement by Natural Selection

Over the years the WOA directors have emphasised the important role of improving the genetic stock as one of the management factors to achieving improved commercial levels of production.  Recently we received a comment that those interested in ostrich farming should shy away from such terms as "genetic improvement programs".   The reason put forward was fear that our consumers may believe we are going down the same track as companies such as Monsanto with their approach to genetic modification (GM).

In the current environment of increasing consumer concerns of GM it is important to be very clear about how the modern GM technology is so very different to “genetic selection by natural selection”.   For millenniums agriculture has improved farm output with farmers selecting seeds from their best crops and selecting breeding males and females from their best livestock genetic lines.  This process has improved agricultural production since the start of agriculture some 10,000 years ago.   As discussed here genetic selection this way has also changed the confirmation of breeds to meet the modern market demands.  Figure 1, from that newsletter illustrates how the Aberdeen Angus has changed from 1959 to 2006.

In livestock genetic improvement by natural selection is achieved by selecting the animals demonstrating the best traits for their breed, or specie, to use for future breeders to improve the breed for their productive traits.  In ostrich these productive traits may be egg laying, they may be specific conformation that provides optimum muscle size for meat production; they will include optimum growth size and feed conversion. In the wild it is the survival of the fittest.

With plants this natural method of genetic improvement is achieved by saving seeds from the best crops to produce a quality crop with optimum yield under the local climatic conditions.

Genetic improvement by natural selection introduces only the genes from the same species, they may be crossed with different breeds or varieties of the same species but they do not introduce genes from different species.  For example in cattle you may cross a Fresian Dairy Cow with a Hereford to achieve a calf that will yield more meat when no further heifers are required to replace older members of the herd.

In recent years something new has crept into genetic development that is alien to genetic improvement by natural selection.  That is genetic engineering where DNA from different species is impregnated into a plant or animals.  The simplest definition of a genetically modified organism is one in which the genetic make-up has been altered in a way that does not happen naturally. The genes, DNA have crossed the specie barrier.

An example of Genetic Modification is taking the gene that programs poison in the tail of a scorpion, and combining it with a cabbage.  These genetically modified cabbages kill caterpillars because they have learned to grow scorpion poison (insecticide) in their sap.  Another example is the gene from a fish that lives in very cold seas has been inserted into a strawberry, allowing the fruit to be frost-tolerant. The item with the greatest concern is the impregnation of DNA into crops such as soya and maize to make it resistant to the herbicide roundup.

The two types of genetic improvement must never be confused.  Genetic improvement by natural selection is normal and essential in commercial agriculture and quite natural so long as the traits selected for and developed do not compromise the animal’s health and well-being.  The controversy on the safety and ethics of genetic improvement is the Genetic Engineering/modification introduction of genes from different species as many scientists still question their long term safety.

An excellent video “The World According to Monsanto” put together by Marie-Monique Robin examines the science supporting the evidence of the safety of GM crops and their development.   At minutes 47.44, during a discussion with Steve Druker reviewing FDA documentation highlighted this statement written by Dr. Louis J Prybal from the FDA Microbiology department:

“there is a profound difference between the types of unexpected effects from traditional breeding and genetic engineering”

The commercial success of ostrich farming depends on identifying the productive genetic material and developing those bloodlines using natural selection and breeding techniques, which can include Artificial Insemination.   There is no need or place for GM technology in ostrich genetic improvement.

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