What are the criteria, indicators and methods for assessing genetically modified organisms and products derived from them for biosafety?
An important step in assessing the biosafety of genetically engineered organisms and the food and other products derived from them is a sanitary and hygienic examination. The following should be checked: the chemical composition of the initial and transgenic plants; Did the biological value and assimilation of GMO-derived products worsen? whether GMOs and products derived from them can cause allergies or affect the human immune system; whether they are toxic, carcinogenic or mutagenic; Do foreign genes affect the reproductive functions of animals and humans? whether the introduced gene can be transferred to other organisms and whether it will be transmitted to the descendants of plants; Does the new gene affect the damage of plants to diseases and pest damage? do not the transgenic plants influence the soil microflora and other components of the biocenosis, etc.
Obligatory and extremely important is also the biomedical evaluation of food products obtained from GMOs. For example, in Russia methodical instructions "Medical and biological assessment of food products from genetically modified sources" have been developed. Methodical instructions establish the procedure for hygienic examination and state registration of food products obtained from genetically modified sources. The methods of medical hygienic, medical and biological evaluation and clinical trials of new types of food products, obtained from genetically modified sources, have been approved. Methodical guidelines are an official publication and their implementation must be strictly controlled by the Ministry of Health of the Russian Federation, as well as by the relevant legal and legal authorities.
What kind of work is carried out in the Republic of Kazakhstan under the Cartagena Protocol?
Kazakhstan is a signatory of the Cartagena Protocol. The study of the problem of regulation of the turnover of GMOs on the basis of Cartagena Protocol of Biosafety legislation allowed Kazakhstan to develop projects "Concepts of state regulation of GMO turnover and control in the Republic of Kazakhstan", as well as a number of normative documents, and create prerequisites for the formation of their regulatory system in the Republic of Kazakhstan. The analysis showed that practically no country has legislation that can prevent unpredictable consequences when creating, using and distributing GMOs. Today, there are two different principles in the world when solving the problems of GMO regulation: the "precautionary principle" that the EU adheres to and the principle of "substantial equivalence" held by the US, Australia, Canada and other countries (EM Ramankulov, 2011).
The monitoring showed that food products containing GM ingredients are uncontrolled to the markets of the Republic of Kazakhstan. It is advisable to adhere to the precautionary principle in its policy, which is based on extreme caution in the use of GMOs and requires the introduction of the labeling "The product contains GMOs", which is very important for ensuring food safety.
An important provision of the Cartagena Protocol is the right to assess the risks of products of genetic engineering activities for making decisions about their imports. As part of the fulfillment of the obligations undertaken, the Government of the Republic of Kazakhstan appointed the Ministry of Agriculture - the national coordinating center, the Ministry of Education and Science - as the competent authority. At the same time, the first ministry is the contact body between Kazakhstan and the Secretariat of the Protocol, and the second is responsible for performing administrative functions. The National Center for Biotechnology of the Republic of Kazakhstan was designated as the center for implementation of the Biosafety Clearing-House (BCH). The latter acts as the central information market, where there is an operative exchange of information on biosafety between all parties to the Protocol.
At present, the draft law of the Republic of Kazakhstan "On state regulation of genetic engineering activities" has been developed, which is currently under consideration by Parliament. The objectives of this bill are to protect the health of the population; environmental protection in the use of GMOs, conservation of biological diversity; ensuring the country's security in the implementation of genetic engineering activities; development of genetic engineering activities, etc.
Thanks to transplantation of embryos taken from a cow that has genetic value, it is possible to obtain a large number of offspring having the same genetic data. Transplantation of embryos is an excellent method, allowing to improve the number of cattle. Export and import of embryos requires much less labor and costs than caring for sterile heifers of valuable breeds.
The leaching of fertilized eggs (embryos) is carried out 7 days after insemination. Do not delay with the timing, as the embryo will begin to attach to the wall of the uterus. When the fetus is received, it is placed in the cow's womb, which will fulfill the role of a surrogate mother. At the same time, the recipient cow does not possess valuable breed properties. If the embryo transplantation happens successfully, then after 280 days (about 9 months) a calf will be born, which significantly surpasses the surrogate mother by genetic qualities.
The first step in carrying out the procedure for the transfer of embryos is the identification of the patient. On the gynecological chair in the prone position, the vagina is treated with distilled water. Do not use antibiotics and antiseptics.
Selected embryos until the moment of transfer are in the incubator, where the necessary component-temperature conditions are maintained. At the time of the procedure, the embryologist opens a package of sterile catheters. The external rigid is established by the reproductologist in the cervical canal of the cervix and is used as a guide for a soft catheter with embryos.
The second step is to load embryos into the catheter. The embryologist takes in the syringe the amount of medium necessary for transfer, inserts into the nest of the internal catheter and slowly presses the piston, releasing the embryos and air bubbles. After this, while the piston is not let go, the reproductive expert removes the catheters and hands them to the embryologist for verification.
In 1% of cases, embryos may remain in the catheter. In this case, the procedure is repeated again. When several embryos are found, a second transfer is carried out 0.5 cm closer to the previous one. An important condition is the efficiency of all manipulations. Long-term presence of embryos in suboptimal conditions can lead to a decrease in their viability.
22. List the stages of embryo transfer technology
Selection of the donor cow
The first step is the selection of the donor cow. Beef producers will differ in their opinions regarding the criteria for selecting a genetically outstanding cow. Whether the criteria be performance records, show ring appeal, or both, consideration must be given to potential dollar value of her calves. As we will see later, considerable expense can be incurred in achieving a successfully transferred pregnancy. Therefore, the sale value of the newborn calf should be high enough to warrant the added expense of this procedure. Because dairy cattle are selected more routinely on one major trait (milk production), the decisions concerning donor cows are actually somewhat less complicated than in beef cattle. However the economic considerations are equally important. Embryo transfer is not a “cure-all.” It does not make average cattle good or good cattle better. It is suitable for a limited number of seedstock producers with beef or dairy cattle that can be breed or species “improvers” for one or more economically important traits.
The potential donor cow should be reproductively sound to produce maximal results. This means that she should have a normal reproductive tract on rectal palpation and have a normal postpartum history, especially with regard to cycle lengths of 18 to 24 days. Both beef and dairy cows should be at least 60 days postpartum before the transfer procedure begins. It has been suggested that prospective donor cows in embryo transfer programs be selected on the following criteria:
• Regular heat cycles commencing at a young age.
• A history of no more than two breedings per conception.
• Previous calves having been born at approximately 365- day intervals.
• No parturition difficulties or reproductive irregularities.
• No conformational or detectable genetic defects.
She should be maintained at the level of nutrition appropriate for her size and level of milk production. Both the very obese cow and the thin cow will have reduced fertility, so it is important that the donor cow be in an appropriate body condition score at the time of embryo transfer. (See OSU Extension Circular E-869 to learn appropriate body condition for beef cattle and OSU Extension Leaflet L-221 for dairy cattle.)
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