Role of ART in Building a Competitive Livestock Industry
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The document discusses the role of assisted reproductive techniques (ARTs) in building a competitive livestock industry. It covers the timeline of ARTs from artificial insemination to cloning. It then discusses various ARTs in more detail, including artificial insemination, embryo transfer, in vitro fertilization, and cloning. The document also summarizes the experience and results of In Vitro Africa in applying these techniques. It concludes that ARTs can help increase livestock productivity and alleviate poverty and hunger in developing countries by allowing for faster genetic improvement.
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Role of ART in Building a Competitive Livestock Industry
- 1. The Role of Assisted Reproductive Techniques (ART’s) In Building a Competitive Livestock Industry Dr. Neil Van Zyl Director – In Vitro Africa
- 2. Presentation Outline: • Introduction • ART’s Timeline • Artificial Insemination • Conventional Embryo Transfer • In Vitro Fertilization • Cloning • In Vitro Africa – Our Experience • Future Directions
- 3. Hunger It is estimated that 827 million people were hungry in developing regions in 2011-13. This numbers has fallen by 169 million, or 17% in the past 2 decades – 658 million Introduction:
- 5. Food security Biotechnologies have contributed immensely to increasing livestock productivity and can help to alleviate poverty and hunger, reduce the threats of diseases and ensure environmental sustainability in developing countries Introduction:
- 6. First generation Artificial Insemination and semen cryopreservation Second generation Conventional Embryo Transfer Third generation In Vitro Fertilization Fourth generation Cloning ART’s Timeline:
- 7. Artificial Insemination: Artificial Insemination (AI) was the first great biotechnology applied to improve reproduction and genetics of farm animals The acceptance of AI technology worldwide provided the impetus for developing other technologies, such as: • Semen Sexing and Cryopreservation • Estrus Cycle Regulation • Embryo Harvesting, Freezing and Culture • In Vitro Fertilization and Cloning
- 8. Artificial Insemination • AI helps prevent the spread of infectious or contagious diseases • Fast increase of genetic development and production gain • It enables breeding between animals in different geographic locations Advantages • AI is a powerful tool when linked to other reproductive biotechnologies, such as: Estrus Synchronization, Semen Sexing and Multiple Ovulation Embryo Transfer (MOET)
- 10. Conventional Embryo Transfer: The Advent of Superovulation Cover of Science Magazine, 1981 Betteridge,2003
- 11. Conventional Embryo Transfer Expected Results: 1 Flushing Session 6 Embryos 3 Pregnancies Expected 50% of pregnancy rate (6 cycles a year) 18 Pregnancies from 1 donor/ year One Flushing session each 60 days
- 12. Conventional Embryo Transfer Advantages • Increased number of calves out of genetically superior cows • Increased marketing opportunities through the sale of offspring, pregnancies, and embryos • Generate more offspring from rare and valuable semen • Larger numbers of offspring can help prove the genetic merits of a female at an earlier age in life Disadvantages • High cost of superovulation program • Requires a higher level of management • Not all donors respond to the superovulation treatment = LOW REPEATABILITY
- 13. IVEP - In vitro production of embryos The IVEP technique started gaining popularity in 2006
- 14. In Vitro Fertilization (IVF): In Vitro Fertilization (IVF) is the process of producing embryos from oocytes by fertilizing them with semen in a Petri dish. Oocytes are first collected from the ovaries of donors by ultrasound-guided follicular aspiration. Oocytes are then placed in a incubator until they are mature to be fertilized the following day (with conventional, sexed-frozen, or reverse- sorted semen).
- 15. Ovum Pick Up (OPU): • Ultrasound guided – non invasive • Allows the used of hormonal stimulated or non stimulated donors • Highly repeatable – Donors can be aspirated every two weeks • Indicus breeds yield a high number of viable oocytes
- 16. Ovum Pick Up (OPU):
- 17. In Vitro Maturation (IVM) Source: The Big Book of Bovine Embryos , University of Florida, 2013 Cumulus Oocyte Complexes (COC’s) after Ovum Pick Up (beginning of IVM)
- 18. In Vitro Fertilization (IVF): Source: In Vitro Africa ®
- 19. Embryo Culture: 2-4 Cells Embryos (2-3 days) 4-6 Cells Embryos (3-4 days) Source: In Vitro Africa ®Source: In Vitro Africa ® After IVF embryos undergo a seven days period of In Vitro Culture in a incubator with controlled atmosphere and temperature Early Development
- 20. Embryo Culture: Expanded Blastocyst (6-7 days) Hatching Blastocyst (7 days) Source: In Vitro Africa ®Source: In Vitro Africa ® Late Development
- 21. Embryo Vitrification: • Vitrification refers to the fast freezing of IVF embryos and provides a higher survival rate, minimal deleterious effects on post-warming embryo morphology. Source: In Vitro Brasil ® • Pregnancy rates after transfer of vitrified IVF embryos are similar from those achieved when transferring fresh embryos
- 22. In Vitro Fertilization: The possibility of using Sexed Semen represents one of the best advantages of the IVF • Semen sexed prior to freeze, and semen sexed after it is frozen (reverse sorted), both work very well in an IVF program • The ability to create up to 95% of the gender desired, eliminates the gestation costs of the unwanted gender • Multiple donors (3+) can be fertilized with one straw of sexed semen = COST EFFECTIVE Optimizing the use of Sexed Semen
- 23. In Vitro Fertilization (IVF) Proven Results Source: In Vitro Africa ®
- 24. In Vitro Fertilization (IVF) Expected Results 1 OPU Session 20 Viable Oocytes 6 Embryos Expected 30% of production using conventional semen 3 Pregnancies Expected 50% of pregnancy rate (24 cycles a year) 72 Pregnancies from 1 donor/ year One OPU session each 15 days
- 25. Conventional ET x IVF: Conventional ET In Vitro Fertilization Lower initial investment – doesn’t require a fully equipped laboratory Requires equipped laboratory and highly trained personal Slight Pregnancy rate advantage More repeatable – donors can be aspirated twice a month More cost effective - Single straw of semen to inseminate multiple donors (sexed semen = cost effective) Heifers and cows near the end of the reproductive life can be used as donors What is the best option?
- 26. In Vitro Africa: Our Experience – Case Studies ALS BEEFMASTERS – North of KwaZulu Natal, South Africa (2012) MATERIALS AND METHODS: • Donors: 16 Stud registered ALS Beefmaster cows, aged 7 to 11 years of age • OPU: 936 oocytes collected over 4 OPU sessions. • IVF: 16 straws of different bulls were used to fertilize the 936 oocytes RESULTS: • Embryo Culture: Total of 259 embryos were produced (28%) • Embryo Transfer: 238 Embryos were transferred (a percentage of the embryos was frozen to act as a genetic bank) • Pregnancies: 118 animals resulted pregnant after embryo transfer (49.6%)
- 27. In Vitro Africa Our Experience – Case Studies ALS BEEFMASTERS – North of KwaZulu Natal, South Africa (2012) CONCLUSIONS: • Thirty four parentage combinations were achieved by mixing oocytes from the different donors with the semen from different bulls • All the donors were mated after the 4 OPU sessions and ALL reconceived! • 118 pregnancies were achieved using oocytes from 16 donors and 16 straws of semen
- 28. In Vitro Africa Our Experience – Case Studies SMALL STOCK IVF– Western Cape, South Africa (2014) MATERIALS AND METHODS: • Donors: 4 Juvenile (pre-pubertal) Boer Goats • OPU: 135 oocytes collected in one session (picked up by laparotomy) • IVF: Refrigerated semen from a male of proven fertility. RESULTS: • Embryo Culture: Total of 47 embryos were produced (34%) • Embryo Transfer: 47 Embryos were transferred to 23 synchronized recipients (2-3 embryos per recipient) • Pregnancies: 19 animals resulted pregnant after embryo transfer (80%)
- 29. Cloning: The Fourth Generation of ART’s Source: In Vitro Africa ® Cloning technology allows breeders to recreate the genotype of a superior animal, providing a source to extend their genetic influence
- 30. Cloning The Fourth Generation of ART’s • Produce quantities of elite individuals for the purpose of large-scale, consistent genetic influence within a herd-building program Breeders most often look at cloning as a technology to: • Produce a genetic twin of an elite animal no longer capable of producing embryos or semen (including steers) • Produce a genetic twin of an elite animal that has died
- 31. In Vitro Africa: Our Experience – Season 2013/14 43% 40% 34% 40% 32% 25% 24% 21% 22% 27% 30% 31% 0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50% Mrt Apr May June July Aug Sept Oct Nov Dec Jan Feb Row Labels Sum of ET/VITR Sum of Cultured Sum of = Mrt 425 981 43% Apr 82 205 40% May 92 271 34% June 32 80 40% July 129 400 32% Aug 416 1636 25% Sept 387 1626 24% Oct 556 2663 21% Nov 827 3824 22% Dec 553 2049 27% Jan 788 2669 30% Feb 342 1097 31% Grand Total 4629 17501 26%
- 32. • Genetic Preservation In Vitro Africa Future Directions • Establishment of an international embryo trading platform • Consulting on reproduction and herd genetic improvement Genetic banking is the cryopreservation and storage of an animal’s genes in order to be available for eventual future use in cloning. Genetic banking is an affordable way to protect your investment, and preserve the option to multiply that investment later through cloning. If you lose an animal genetic banking is your insurance. The South African livestock population is of a very high quality and could be a reliable source of superior genetic material for genetic improvement projects in Africa.
- 33. • Embryo Sex Determination Prior to Transfer In Vitro Africa Future Directions © 2013 Thermo Fisher Scientific Inc. Pink fluorescence indicates presence of bovine Y chromosomal DNA in the sample. Female samples do not show fluorescence Embryo sexing prior to embryo transfer represents a powerful tool in modern cattle breeding. A small biopsy of a single embryo is taken and analyzed by PCR to determine the its sex. Pregnancies after transfer of biopsied embryos are not significantly different from the rates obtained using intact ones.
- 34. Improvement in Production Efficiency Figure 1. Genetic trend for WW205 in the Afrikaner Figure 2. Genetic trend for WW205 in the Bonsmara Proceedings, 10th World Congress of Genetics Applied to Livestock Production Did Genetic Change Improve Production Efficiency in Three Landrace Breeds of South Africa F.J. Jordaan, et al.
- 35. The value of genetic improvement In South Africa the value over the last ten years has been U$0,45 billion or U$ 4 per calf weaned - Breedplan $$ US 4
- 36. Concluding remarks 1. Livestock is the backbone of rural economy for millions of people in Africa Population sizes of livestock species in tropical Africa (1986). • Cattle 161 135 000 (85 893 000) • Sheep 121 388 000 (67 939 000) • Goats 142 711 000 (69 620 000)
- 37. Concluding remarks 2. Monetary value of research, developmental work spend on cash crops vs. livestock 3. Nucleus breeding programs – Jan Rendel 4. Value of ART in creating a competitive livestock industry THANK YOU
Notes de l'éditeur
- Mister Chairman, guests of honour, ladies and gentleman. In the short period of time at my disposal, I will introduce you to the magnificent world of ART. In this case I am not referring to the gifted people who enlighten this world with their paintings, sculptures, poems or stories, but to assisted reproductive techniques and its role in the enhancement of genetic improvement in farm animal species and how it can contribute to building a competitive livestock industry
- After introducing the problem statement to you, I will be talking about four techniques that make up the ART timeline. The techniques are: Artificial Insemination, MOET, In Vitro Production of Embryos and Cloning. I would also like to share some of our personal experiences in South Africa with you and then attempt to address at least part of the problems facing the livestock industry in Africa.
- If one looks at the problem statement, two very prominent issues immediately come to mind. The first is hunger. It is estimated that 827 million people were hungry in developing regions in 2011-13. This numbers has fallen by 169 million, or 17% in the past 2 decades. If these figures are still applicable today, 658 million people are still in need. (1) Despite the reduction in the number of people considered to be undernourished, we still have a serious problem.
- In countries such as: Ethiopia, Mozambique, Zambia and Malawi, 35% of the population are considered to be hungry (very high). In Uganda, Kenya and Tanzania, Namibia, Botswana and Zimbabwe 25-34, 9% (high) are hungry, 15-25% in Angola (moderately high); many countries in West Africa are (moderately low). The white areas represent less than 5% (South Africa). The grey areas present the area which did not present any data.
- The second problem is food security. Status of supply of beef in the world, where developed markets are under supplied.///// Africa’s livestock population might solve the problem as far as numbers are concerned, but little attention was given to quality of the product available to world markets. No attention is given to the lack of infrastructure or underdeveloped supply chains in most African countries. Bringing biotechnology to these countries or regions can present one of the methods of addressing the problem and at the same time ensuring that the livestock industries become more competitive in the a world where the demand for animal protein as a food source for many countries outside of Africa, such as China, the Middle east, India, etc.
- In the timeline of ART we will look at: Artificial Insemination, Conventional Embryo transfer (MOET), In Vitro production of embryos (IVEP) and Cloning.
- Artificial Insemination (AI) was the first great biotechnology applied to improve reproduction and genetics of farm animals The acceptance of AI technology worldwide provided the impetus for developing other technologies, such as: Semen Sexing and Cryopreservation; Estrus Cycle Regulation; Embryo Harvesting, Freezing and Culture; In Vitro Fertilization and Cloning.
- Advantages of artificial insemination are the following: AI helps prevent the spread of infectious or contagious diseases; Fast Increase of genetic development and production gain; It enables breeding between animals in different geographic locations; AI is a powerful tool when linked to other reproductive biotechnologies, such as: estrus synchronization, semen sexing and Multiple Ovulation Embryo Transfer (MOET) (3) 100% increase in milk production in the USA in the last 40 years
- Conventional Embryo Transfer (MOET) Conventional Embryo Transfer is explained in the accompanied illustration. The donor cow is stimulated by administering hormones over a period of 4 ½ days and will normally come into standing heat 6 days after initiating super ovulation. Artificial insemination or natural service will take place over a period of 24 hours. Seven days later the developed embryos will be flushed from the uterus with a three way catheter. The embryos will be located and selected in the laboratory. After classification and washing of the embryos, they will be transferred to recipient animals which were presynchronised to be in the same stage of the reproductive cycle. A pregnancy diagnoses will be done 60 days after being transferred. The excess embryos can be frozen and stored for future use.
- The result of MOET can be seen in the photo. Ten calves were born from a single flushing ( one cow of a superior genetic make up ) and ten commercial cow with a lower economic value were used as surrogate mothers.
- With MOET one female donor cow can be flushed every sixty days (six times in one year). An average of six embryos will be recovered and result in 18 pregnancies annually (50% pregnancy rate)
- Advantages of MOET Increased number of calves out of genetically superior cows; Increased marketing opportunities through the sale of offspring, pregnancies, and embryos; Generate more offspring from rare and valuable semen; Larger numbers of offspring can help prove the genetic merits of a female at an earlier age in life. Disadvantages High cost of super ovulation program; Requires a higher level of management; Not all donors respond to the super ovulation treatment = LOW REPEATABILITY.
- IVEP - In Vitro Production of Embryos. The first In Vitro Produced (IVP) calf was born in 1981, but the technique only became popular in 2006.
- In Vitro Fertilization (IVF) is the process of producing embryos from oocytes by fertilizing them with semen in a petri dish. Oocytes are first collected from the ovaries of donors by ultrasound-guided follicular aspiration. Oocytes are then placed in an incubator until they are mature to be fertilized the following day with conventional, sexed-frozen, or reverse-sorted semen.
- The advantages of IVEP are: Ultrasound guided – non invasive; Allows the use of hormonal stimulated or non stimulated donors; Highly repeatable – Donors can be aspirated every two weeks; Bos Indicus breeds yield a high number of viable oocytes.
- The photos illustrate an OPU veterinarian in action. After collection of the oocytes, they undergo three basic steps in the laboratory: In Vitro Maturation, In Vitro fertilization and In Vitro culture
- The next slide shows a Cumulus Oocyte Complexes (COC’s) after Ovum Pick Up (beginning of IVM)
- In Vitro Fertilization (IVF) A small volume (5-10 ul) of washed semen is added to a drop (100ul) containing up to 30 oocytes.
- In Vitro Culture (IVC) After IVF embryos undergo a seven days period of In Vitro Culture in an incubator with controlled atmosphere and temperature
- This slide shows two embryos in the later stages of development. On the left is an expanded blastocyst. This embryo is ready to be transferred to a recipient cow or to be vitrified. The embryo on the right has started to hatch and is not suitable for vitrification.
- Vitrification refers to the fast freezing of IVF embryos and provides a higher survival rate, minimal deleterious effects on post-warming embryo morphology. Pregnancy rates after transfer of vitrified IVF embryos are similar from those achieved when transferring fresh embryos
- Optimizing the use of Sexed Semen The possibility of using Sexed Semen represents one of the best advantages of the IVF: Semen sexed prior to freeze, and semen sexed after it is frozen (reverse sorted), both work very well in an IVF program; Multiple donors (3+) can be fertilized with one straw of sexed semen = COST EFFECTIVE; The ability to create up to 95% of the gender desired, eliminates the gestation costs of the unwanted gender. (4)
- This slide shows a large group of calves born from an IVEP program
- With In Vitro Production of Embryos one donor can be aspirated every two weeks without any significant damage to the reproductive tract. On average twenty oocytes will be collected. Six embryos should develop from that at a production rate of 30%. With 24 cycles per year, a total of 72 pregnancies can be obtained from one donor in one year.
- When comparing the two techniques: Conventional ET (MOET) has a lower initial investment. A fully equipped laboratory is not required and there is a slight pregnancy rate advantage. IVEP on the other hand requires equipped laboratory and highly trained personal. The technique is more repeatable (donors can be aspirated twice a month) and more cost effective (a single straw of semen can fertilize oocytes from multiple donors). Heifers and cows near the end of the reproductive life can also be used as donors.
- I would like to share some of our experiences with you. The first case study is on cattle from the ALS BEEFMASTER STUD in KwaZulu Natal, South Africa (2012) The materials and methods used are the following: Stud registered ALS Beefmaster cows – 16 in number, 7 to 11 years of age, were used, 936 oocytes collected over 4 OPU sessions and 16 straws of different bulls were used to fertilize the 936 oocytes. A total of 259 embryos were produced (28%) of which 238 were transferred (a percentage of the embryos was frozen to act as a genetic bank). 118 animals resulted pregnant after embryo transfer (49.6%)
- In summary, 118 pregnancies were achieved using oocytes from 16 donors and 16 straws of semen All the donors were mated after the 4 OPU sessions and ALL reconceived! Thirty four parentage combinations were achieved by mixing oocytes from the different donors with the semen from different bulls
- The second case study is on SA BOER GOATS in the Western Cape, South Africa (2014). Four juvenile (pre-pubertal) South African Boer Goats were collected via laparotomy. 135 oocytes collected in one session (picked up by laparotomy). Refrigirated semen from a male of proven fertility was used. A total of 47 embryos were produced (34%) which were transferred to 23 synchronized recipients (2-3 embryos per recipient). 19 animals became pregnant after embryo transfer (80%) This case proves that pre-pubertal animals can be an excellent source of oocytes.
- Cloning technology allows breeders to recreate the genotype of a superior animal, providing a source to extend their genetic influence.
- Breeders most often look at cloning as a technology to: Produce a genetic twin of an elite animal no longer capable of producing embryos or semen (including steers); Produce a genetic twin of an elite animal that has died; Produce quantities of elite individuals for the purpose of large-scale, consistent genetic influence within a herd-building program
- The table shows the results for the period March. 2013 to February 2014. 17 501 oocytes were collected resulting in 4629 embryos.
- Future Directions for In Vitro Africa is to: Establishment of an international embryo trading platform The South African livestock population is of a very high quality and could be a reliable source of superior genetic material for genetic improvement projects in Africa. Consulting on reproduction and herd genetic improvement and Genetic Preservation Genetic banking is the cryopreservation and storage of an animal’s genes in order to be available for eventual future use in cloning. Genetic banking is an affordable way to protect your investment, and preserve the option to multiply that investment later through cloning. If you lose an animal genetic banking is your insurance.
- Embryo Sex Determination Prior to Transfer Embryo sexing prior to embryo transfer represents a powerful tool in modern cattle breeding. A small biopsy of a single embryo is taken and analyzed by PCR to determine the sex. Pregnancies after transfer of biopsied embryos are not significantly different from the rates obtained using intact ones.
- In the two graphs presented, the improvement in production efficiency was recorder over a period of 25 years in the Bonsmara and Afrikaner breeds. In both the breeds a 205 day weaning weight was obtained. (5) rafieke van Bonsmaras en Afrikaner
- In South Africa the value of genetic improvement over the last ten years has been U$0, 45 billion or U$ 4 per calf – Breedplan
- In closing, ladies and gentleman, please allow me to comment on the following: 1. Livestock is the backbone of rural economy for millions of people in Africa H. E. JAHNKE, G. TACHER, P. KEIL and D. ROJAT (1986) did a study on Trypanosomiasis where they particularly emphasized ruminant species such as cattle, sheep and goats as they play the major role in livestock production and are the species mainly affected by the disease. They defined Tropical Africa as sub-Saharan Africa excluding the South African Republic. It covers 23 million km2. What is interesting are the figures they came up with which are reflected in the slide. Source: FAO, 1987a - FAO, 1986b. In Sub-Sahara Africa there are 161 135 000 cattle, 121 388 000 sheep and 142 711 000 goats. In Eastern Africa there are 85 893 000 cattle, 67 939 000 sheep and 69 620 000 goats. Source: FAO, 1987. I do not have time today to share all the interesting facts that these researchers came up with, but here are a few: Ruminant species, excluding camels constitute 82% of the total TLU. They are by far the most important livestock species in tropical Africa. Of the developing world, the African continent has 17% of the cattle and 26% of the small ruminant population; these percentages change to 11 and 17% respectively when compared with world populations (Food and Agriculture Organization of the United Nations [FAO], 1986a,b). Productivity differs greatly between developed and developing countries. The latter have nearly 70% of the bovines and buffaloes in the world, but produce only 29% of the meat and 23% of the milk. The developing countries have 64% of the small ruminant population and produce 54% of the meat (Hoste, 1987). The productivity of bovines is about 15 kg meat per head per year in developing countries versus 79 kg in the developed world. This statistic is relatively better for small ruminants, whose productivity is 4.6 kg meat per head per year in the former and 6.5 kg in the latter (Hoste, 1987). Meat productivity per head of cattle and per small ruminant in Africa, at 14 and 3.7 kg per head, respectively, is a little less than the average of all developing countries. (Hoste, 1987). Milk productivity is much lower in developing countries. It is estimated to be 90 litres per head of cattle per year versus 900 litres in the industrialized world (Tackier, 1982). This very low rate of productivity of livestock and labour in developing countries, especially in Africa, suggests that production systems are faced with major constraints and/or are managed for goals other than just meat or milk production.
- 2. Monetary value of research and developmental work spend on cash crops versus livestock. Most of the development work in Africa focuses on cash crops, while livestock is often neglected. 3. Historical breeding programs JAN RENDEL presented a paper on THE ROLE OF BREEDING AND GENETICS IN ANIMALPRODUCTION IMPROVEMENT IN THE DEVELOPING COUNTRIES at the Symposium on Animal Genetics: X I I I International Congress of Genetics in the 60’s He said “Availability of animal protein for human consumption is very low in the developing countries mainly because of low productivity of existing livestock; ways and means to improve productivity through breeding are discussed and some basic issues requiring further research pointed out” All this was before MOET and IVEP became tools for genetic improvement The East African Community Livestock & Fisheries Sector’s overview of July 2011 stated the following: “The overall goal of animal production at regional level is to produce enough quality animals and animal produce to match the requirements for the rapidly increasing population and create surpluses for export” 4. The value of ART in creating a competitive livestock industry With all these fact and figures in mind, mister chairman, ladies and gentleman the question is not whether ART can assist in building a competitive livestock industry, but rather whether competitiveness can be achieved without ART. Thank you very much.