Review on Potential of Reproductive Technology to Improved Ruminant Production in Ethiopia

DOI: 10.7176/JBAH/10-8-02 Publication date: April 30 th 2020 INTRODUCTION Reproductive technology encompasses all current and anticipated uses of technology in human and animal reproduction, including assisted reproductive technology, contraception and others (Mapletoft and Hasler, 2005). Research into physiology and embryology has provided a basis for the development of technologies that increase productivity of farm animals through enhanced control of reproductive function. Animal Biotechnology represents an expanding collection of rapidly developing disciplines in science and information technologies. The livestock provides many opportunities to utilize these disciplines and evolving competencies. Individually, these are powerful tools capable of providing significant improvements in productivity. Combinations of these technologies coupled with information systems and data analysis will provide even more significant changes in the next decade. Various techniques have been developed and refined to obtain a large number of offspring from genetically superior animals or obtain offspring from infertile (or sub fertile) animals (Naqvi et al ., 2001; Blackburn, 2004). Based on the progress in scientific knowledge of endocrinology, reproductive physiology, cell biology and embryology during the last fifty years new bio techniques have been developed for and introduced into animal breeding and husbandry (Wrathall  et al ., 2004). Among them are estrus synchronization/induction, artificial insemination, Multiple Ovulation Induction and Embryo Transfer (MOET),  in vitro embryo production (IVP) and cloning by Nuclear Transfer (NT) all are components of the tool box for present and future applications (Betteridge, 2003). Techniques are now available to get genetically improved farm animals in large numbers. This involves collection of the fertilized egg from genetically superior female which ovulate spontaneously or are induced to super ovulate (Wolf  et al . , 2000). The current efficiency for producing transgenic animals particularly farm animals, is low and the cost is high. Success in the production of transgenic farm animals requires an adequate animal facility and dedicated teams of embryologists, veterinarians, animal scientists and molecular biologists. Ethiopia has over 57.83 million indigenous cattle, and about 13.5million are breeder cows and 28.89 million sheep out of which about 14 Million are kept for breeder and 29.7 million goats out of this 12.6 million are kept for breeder (CSA, 2015/16). Average milk production from local cows is also low, estimated at 1.37 liters/cow per day (CSA, 2014). This result in a total annual milk production of 3.81 billion liters and about 50% of this goes to calves Per capita milk consumption is low and stands at 19 kg/year FAO (2011). Therefore, Ethiopia needs to work hard on improving the work of productive and reproductive performance improvements of cattle through appropriate breeding and related activities (CSA, 2006). In spite, of the presence of large and diverse animal genetic resources, the productivity (meat and milk) of livestock remains low in many developing countries including Ethiopia for various reasons, such as inadequate nutrition, poor genetic potential, inadequate animal health services and other management related problems (Lobago, 2007). Cattle breeding are mostly uncontrolled in Ethiopia making genetic improvement difficult and an appropriate bull selection criteria have not yet been established applied and controlled which makes genetic improvement difficult (Webb,2003; Abraham ,2014). Given the considerable potential for smallholder income and employment generation from high-value dairy products, development of the dairy sector can contribute significantly to food security and nutrition of the country (Desalegn et al., 2009). On the other hand, artificial insemination (AI), the most commonly used and valuable biotechnology has been in operation in Ethiopia for over 30 years. Nevertheless, the efficiency and impact of the AI operation has not been well-documented (Engida, 2012). This paper is review status of reproductive technology to improved ruminant production in Ethiopia.

productive and reproductive performance improvements of cattle through appropriate breeding and related activities (CSA, 2013). The average lactation yield of indigenous cattle breeds ranges between 400 to 680 kg, have been reported whereas those of the crossbred cows range between 1200 to 2500 liters of milk over a lactation period of 279 days Belete et al. (2010). According to (Mekonen et al., 2012) Cattle have a significant contribution to the livelihoods of the farmers. They serve as a source of draught power for the agrarian population, by contributing towards the supply of milk, meat, manure besides being a source of ready cash, cattle also contribute significantly role to the socio-cultural values of the society. Appropriate breeding by using reproductive technology has great improvement on average lactation yield of dairy cattle Belete et al. (2010).

Constraints of Production System in Ethiopia
The constraints include subsistence-oriented production system, lack of awareness of improved livestock production system (by farmers, pastoralists/agro-pastoralists, professional and policy and decision-makers), feed resources, animal diseases and markets (Lobago, 2007;Azage et al., 2016). The burden of this huge livestock resource is also compromised by the poor reproductive performance, less use of reproductive technology with an annual calving rate of about 45%. Out of this huge number of breeder cows, the annual number of calves born is only about 5.04 million. The remaining 6.16 million cows have to be fed and managed without producing either milk or calves. Again, about 15% of the calves die before attaining weaning age. This is a loss of about 756,000 calves every year. This huge reproductive wastage and pre-weaning calf losses could be averted through improved fertility management and reduced calf morality (Azage et al., 2016).

Purposes of Using Reproductive Technology
The main objectives of using reproductive biotechnologies in livestock are to increase production, reproductive efficiency and rates of genetic improvement or these reproductive technologies were initially to speed up the genetic improvements of farm animals by the increase of offspring of selected males and females and the reduction of the generation intervals.

Types of Reproductive Technology Artificial insemination
This technology has now become a practical technology in commercial dairy cattle programs in both developed and developmental countries. Artificial insemination (AI) is the process of collecting sperm cells from a genetically superior male animal and manually depositing them into the reproductive tract of a female. The first successful insemination was performed by Spallanzani, (1784) in a bitch. Pioneering efforts to AI were begun in Russia in 1899 by Ivanoff Ivanoff (1922) had studied AI in domestic farm animals, dogs, foxes, rabbits, and poultry. Later on, this technique was performed by various researchers worldwide in different species. Use of frozen semen (Polge et al., 1949) revolutionized the AI program through worldwide transport of semen. Initially, the AI was used to spread improved indigenous breeds which were followed by the introduction of crossbreeding, hence grade up the local low yielder breeds. The AI technology maximizes the use of outstanding males, dissemination of superior genetic material, improve the rate and efficiency of genetic selection on the male side, introduction of new genetic material by import of semen rather than live animals and thus, reducing the international transport costs, enabling the use of frozen semen even after the donor is dead and reduces the risk of spreading sexually transmitted diseases (Foote, 2002). Various aspects of AI technology have been globally standardized for each species. A large number of AIs are performed globally, more than 100 million cattle, 40 million pigs, 3.3 million sheep and 0.5 million goats are artificially inseminated every year (Boa-Amponsem and Minozzi, 2006). The conception rate from AI programs in developing countries is relatively low and therefore the desired goal from it has not been achieved, which may be due to the lack of proper management and poor technical skill. The AI will become more effective and economic only when farmers will have access to considerably better technical and organizational facilities.
Artificial insemination offers several potential advantages over natural service, of these, the reason most commonly advocated is as a means of genetic improvement and others include cost effectiveness, disease control, safety breeding, flexibility, and fertility management ( Ball and peter, 2004;Gebremedhin, 2005;Holm et al., 2008). Artificial insemination (AI) management programs are highly dependent upon accurate heat detection procedures to achieve successful results. Conducting two to three daily visual heat detection observations of the cattle herd during the AI breeding season could lead to economic benefits to beef and dairy producers. Efficient heat detection, however, is time-consuming, labor-intensive, and requires good management and recordkeeping. Undetected heats in an AI program play a significant role in lowering reproductive efficiency by increasing the number of "open days," which in turn results in longer calving intervals and ultimately reduces the net return to the producer (Dup onte, 2007).

Number of service per conception (NSPC)
According to (Menale et al., 2011) NSPC is defined as the number of services/ inseminations required for a successful conception. It depends largely on the breeding system used and influenced by both genetic and nongenetic factors viz. season; that related to availability of feed, semen quality, lactation length, milk yield and parity (Gebrekidan et al., 2012). Fertility of the bulls is commonly measured by calculating the percentage of cows those are pregnant after a single service (Quintela et al., 2004: Debir et al., 2016. Numbers of service per conception is presented as follows.

Enrollment of semen producing bulls
According to (Zewde, 2007), the selection criteria of bulls for AI service must include record-based pedigree information, individual performance as regularly recorded starting from the time of birth, which should include birth weight, subsequent weight increments. Later on progeny testing and general health status should also be parts of the selection criteria. Thus, AI service is weak and even declining due to inconsistent service in the smallholder livestock production systems of the Ethiopian highlands. The problem is more aggravated by wrong selection and management of AI bulls along with poor motivations and skills of inseminators (GebreMedhin, 2005;Alazar et al., 2015). Registration as semen producing bulls is not only enough, proper managements and Bull health control is essential to sustain semen production. Therefore, Disease prevention in bulls has been considered as essential as in breeding females (Hansen, 2006). Unless it is made possible to make full control of the health of bulls selected for semen production, the disadvantages of artificial insemination in disseminating diseases will be much higher (Zewde, 2007). The frequency of tests made and the diseases tested at NAIC are not sufficient (Agegnehu, 2007). According to the international animal health code (2001) of the Office International des Epizooties (OIE), donor and teaser animals should be tested for the following specific diseases: Bovine Brucellosis, Bovine Tuberculosis, Bovine Viral Diarrhea, Infectious Bovine Rhinotracheitis, Campylobacter fetus/subspecies veneralis, Trichomonas fetus. Nevertheless, semen-producing bulls at NAIC in Ethiopia are tested only for brucellosis and tuberculosis and yet not on regular basis due to many associated constraints (Agegnehu, 2007).
Journal of Biology, Agriculture and Healthcare www.iiste.org ISSN 2224-3208 (Paper) ISSN 2225-093X (Online) Vol.10, No.8, 2020 Artificial insemination technician efficiency According to Makh (2008) the site of semen deposition has been an important factor in the success of AI in cattle accurate placement is important for achieving good conception rates. Faulty insemination technique is major factor causing low conception rate in many herds accurate insemination to detail, a clear understanding of reproductive anatomy and the ability to identify the target area and properly position the insemination road.

Heat detection and timing of insemination
Knowledge of estrus behavior and the estrus to ovulation interval is essential for estimating the best time to artificially inseminated cattle (Reolofs et al., 2010). According to kuster (2004) and Tegenu, (2016), Heat detection is basic to reproductive success in artificially bred herds. A Frequent question concerning AI is what time during estrus should cow in bred for greatest chance of conception? Since estrus may last from 10-25 hours there is considerable latitude in possible time of insemination. Maximal conception is obtained when cows are inseminated between mid-estrus and end of standing estrus, with good results up to 6 hours after estrus. A successful heat detection program and subsequent proper timing of insemination will pay dividends in increasing reproductive efficiency.

Distribution of semen in Ethiopia
NAIC distributes semen to nine sub-centres: two in Oromia (Nekemt and Asella), two in SNNP (Wolaita and Wolkite), two in Amhara (Bahir Dar and Dessie), two in Tigray (both in Mekelle) and one in Harari (Harar). These places are selected for their strategic locations and all the semen is sent on request to the Regional Agricultural Bureaus, which are responsible for distributing liquid nitrogen and semen to sub-centers in their respective regions. Zelalem et al, (2011), Ethiopia, for various reasons, such as inadequate nutrition, poor genetic potential, inadequate animal health services and other management related problems (Fikre, 2007). Livestock productivity in Ethiopia is said to be poor due to a number of reasons among which is the low genetic capacity of the indigenous cattle. In the country the poor genetic potential for productive traits, substandard feeding, poor health care and management practices are the main contributors to low productivity (Belay et al., 2012). In order to improve the low productivity of local cattle, selection of the most promising breeds and cross breeding of these indigenous breed with high producing exotic cattle has been considered as a practical solution. Crossbreeding work in Ethiopia was initiated in the early 1950s, following this initiation a number of governmental (example, Ethiopian Agricultural Research Organization, Ministry of livestock and fishery, National Artificial Insemination Center, Higher Learning Institutes) and non-governmental organizations (International Livestock Research Institute and Swedish International Development Agency) have worked in the development of the dairy sector. These crossbreeding activities, unfortunately, were not based on clearly defined breeding policy with regard to the level of exotic inheritance and the breed types to be used. The unplanned crossbreeding had also threatened the genetic resources base of the country (Azage, 2011). Similarly, the effect of crossbreeding has also been disastrous, especially in the smallholder sector where less attention is paid to matching the genotype to the environment (Kahi 2002;Chencha, 2012).

The position of pregnancy rate/conception rate in Ethiopia
Pregnancy rate/conception rate refers to the percentage of cows /heifers diagnosed pregnant out of total number of cows/ heifers inseminated (Miah et al., 2004). According to (Hamid 2012;Adebebay et al., 2013;Tewodros et al.,2015) an averages of conception rate have been reported 48.1%, 13.7 % and 31.29%, respectively in different milk shade area of the country. The average national conception rate 27% have been reported Desalgn (2008). Conception/ reproductive performance is associated to either to the management factors (such as husbandry, feeding, estrus detection and time of artificial insemination, semen handling) or cow factors such as age, body condition score, post-parturient problem, disease events, milk yield and genetics.

Estrus synchronization
Reproductive failure in inseminated cattle results from poor fertilization and embryo survival. Several factors affect fertilization rates, but the greatest impact was observed for high producing cows under heat stress, when fertilization was only 55%. Once fertilization has occurred, the fate of a successful pregnancy is then determined Journal of Biology, Agriculture and Healthcare www.iiste.org ISSN 2224-3208 (Paper) ISSN 2225-093X (Online) Vol.10, No.8, 2020 15 by the survival of the embryo and fetus (Santos et al., 2004). Perfect detection of estrus is crucial for good husbandry practice of cow. Estrus synchronization is the alternative strategy to bypass the critical problem of estrus detection (Paul et al., 2015). Synchronization of estrus implies the manipulation of the estrous cycle or induction of estrus to bring a large percentage of a group of females into estrus at a predetermined time (Odde, 1990). Estrus synchronization programs improve reproduction efficiency by reducing the length of breeding and calving seasons and increasing calf weaning weights (Gupta et al., 2008). The reproductive performance of a dairy herd has a significant effect on the profitability of that herd. Common measures of reproductive performance are days to first service, days to conception, calving interval, services per conception, conception rate, estrus detection rate, and pregnancy rate. Pregnancy rate is an overall measure of reproductive performance (AlbertdeVries et al., 2012).
Besides Synchronization is regulating follicular development; provide multiple stimuli designed to induce anestrous females to cycle, and treatments that synchronize ovulation for the purposes of timed AI. Besides, the wide application and success of AI and estrus synchronization throughout the developed world and the success rate in African and other developing countries is still low owing to a number of technical, system related, financial and managerial problems (Tropentag, 2012). Synchronization of the estrous cycle has the potential to shorten the calving season, increase calf uniformity, and enhance the possibilities for utilizing AI (Lamb, 2010). The aim Estrus Synchronization is to bring a group of female for parturition: decrease labor, and financial resources, decrease calving period reduce calving season more uniform weaning weights. Reduce or eliminate estrus detection needed for artificial insemination (Azage, 2012). Truthful economic benefits of improved reproductive performance are not simple to estimate. When reproductive performance improves, all changes in cash flows that result from the improvement must be accounted for. So for a good analysis, we need at least realistic estimates of lactation curves, feed intake, the risk of involuntary culling, and prices such as for milk, feed, labor, semen, fertility drugs, calves, replacement heifers and cull cows (Albert de Vries et al., 2012). Estrus synchronization can avoid or reduce the need for estrus detection, and increases the fertility and productivity of cattle (Larson et al, 2006). Furthermore, estrus synchronization facilitates planning of AI, shortens first day service in postpartum cows, reduces the calving interval and helps to maintain uniform calf crops and replacement heifers (lamb, 2010;Larson et al., 2006). However, the benefits from this method can only be obtained from a reproductively healthy cow. Non-cycling cows or anestrous cows, a condition where the cow does not cycle due to insufficient natural hormonal stimuli cannot be induced to restore her reproductive cycle using this technique (Pennington, 2013). The technique of estrus synchronization can significantly assist the already existing reproductive management tools. The technology needs to be disseminating to the cattle breeder, veterinarians and industry personnel to ensure they are adopted at the producer level and to provide the necessary technical support to achieve optimum results (Lamb, 2010).

Estrous synchronization protocols
Various estrous synchronization protocols are available in the world. Some commonly used estrous/ovulation synchronization protocols in dairy cattle includes use of prostaglandin (one shot method and two-shot method) and progestin (Ovsynch and Cosynch) (Rick, 2013). Current world-wide research is focused on the development of methods that effectively synchronize estrus by decreasing the period of time over which estrus is detected, hence facilitating the use of fixed time AI (Patterson et al., 2011). Progesterone based estrus synchronization protocols are more advantageous than others. One shot method: A single injection of PGF2α is given to cyclic females, and then these females are bred as express estrus or the method used only for cows having a functional CL will be injected. These cows should show sign of oestrus within 2-3 days Lucia (2013). The disadvantage of this program is that 20-25% of the females will not respond to the injection, likewise, the method has the disadvantage that animals have to be palpate or scan prior to be injected Lucia (2013) but the advantages are the lower cost of one injection and that females are only handled once other than for breeding (Islam, 2011). Two shot method: The most common method of synchronization with PGF2α is to inject all animals and breed those that come into heat over the next 5 to 7 days. The two injections of prostaglandin spaced 14 days apart (Islam, 2011). Detection of estrus is not required before or between injections. All cycling cows should respond to the second injection regardless of what stages of the estrous cycle were in when the first injection was administered. Remember the non-cycling cows will not generally respond to prostaglandin products. The advantage of this option is that more cows should come into estrus at any given time than with the one shot options. The disadvantage is that it involves the cost and labor of administering two injections of prostaglandin to all cows (Michael and Thomas, 2005;Păcală, et al., 2009). Prostaglandin: Prostaglandin is the first method of heat synchronization that depends on the presence of a functional CL particularly in the diestrus stage of the estrous cycle (day 7 to 17 of the cycle) (Cordova-Izquierdo et al., 2009). Its effectiveness usually affected by heat stress, asynchronous ovarian events exhibiting incomplete or delayed luteolysis, and weak or delayed estrous (Mgongo et al., 2008;Lamb, 2010;Adebabay, 2013) similarly, Prostaglandin is used to synchronize estrus in dairy cattle operations to improve the efficiency of AI byinducing Journal of Biology, Agriculture and Healthcare www.iiste.org ISSN 2224-3208 (Paper) ISSN 2225-093X (Online) Vol.10, No.8, 2020 the regression of the corpus luteum and subsequently lead to the expression of estrus and ovulation with 2 to 5 days after their administration (Holm et al., 2008;Murugavel et al., 2010). Pregnancy rate from 61.4 to 65% in cycling and up to 47% in anestrus cows have been reported after a single injection of PGF2α (Perry, 2010). According to (Baruselli et al., 2006) suggested that treatments using progesterone releasing devices and GnRH/ improve reproductive performance in Bosindicus cows due to their beneficial effect on Luteinized hormone pulse frequency, follicular growth and ovulation. In Ethiopia in different milk shade reported that the rate of estrus response in a single injection of prostaglandin protocol at the milk shade and farmer level was 97.7% and 91.3%, respectively (Debir et al., 2011;Girmay et al., 2015) and likewise Adebebay et al. (2013) the average response rate of the cows to prostaglandin (PGF2α) injection or its analogue was 89.3%. (Gupta et al., 2008). The advantage of Prostaglandin or its analogue (PGF2α) in a synchronization protocol shortens the estrous cycle when used alone and estrus is observed within 2 to 7 days' post injecting the hormone.

Multiple Ovulation and embryo transfer (MOET)
Multiple ovulation and embryo transfer (MOET) is often referred as the assisted reproductive technology that is "to the female, while AI is to the male", i.e. a method of producing more offspring from a genetically valuable female than would be possible by natural breeding. Meanwhile, MOET has not yet become a widespread tool for genetic improvement for a variety of reasons including its costs, technical demands, and variable and unpredictable efficiency (Cognié et al., 2003). An early review by Callesen et al. (1996) showed the significance of MOET in dairy cattle. Meanwhile, the use of MOET procedures remains affected by a high variability in the ovulatory response to hormonal treatment and by a low and variable number of transferable embryos and offspring obtained. This variability has been classically identified with both extrinsic (source, purity of gonadotrophins and protocol of administration) and intrinsic factors (breed, age, nutrition and reproductive status) (González-Bulnes et al., 2004). In a more recent review, Menchaca et al. (2010) summarized that the application of recently acquired knowledge has resulted in relevant improvements in MOET programs in small ruminants. Embryo transfer technology is an important tool to improve livestock at faster rate as well as gives an opportunity to utilize the genetic contribution of both male and female at the same time. Nicholas and Smith (1983) reviewed that with the help of ET (embryo transfer) or MOET (multiple ovulation embryo transfer) techniques a faster improvement of livestock, rapid expansion of elite animals, genetic gain, accelerated herd development and conservation of rare genetic stocks could be achieved.
Embryo transfer and other reproductive technology facilitate genetic improvement and have been successively used for rapidly multiplying the population of elite breeds of cattle (Thibier, 1996), buffalo (Madan et al., 1993), sheep (Holm et al., 1996), goat (Pawshe et al., 1994and Baldassarre and Karatzas, 2004, horse (Squires et al., 1999) and pig (Hazeleger and Kemp, 1999). In 2002, approximately 539,680 ETs were performed worldwide, mainly in dairy cattle, with 62% being transferred in North America and Europe, 16% in South America and 11% in Asia (Madan, 2005). Moreover, the latest report of the International Embryo Transfer Society Data Retrieval Committee estimated the number of ET transferred to be 800,000 embryos in cattle (Thibier, 2009), 25,000 in sheep, 7000 in goat, 30,000 in pig and 12,000 in horses (Thibier, 1996) were transferred worldwide (two thirds as in vivo derived embryos and one third as in vitro produced) with 55-70% conception rate (Thibier, 2009).
After AI and estrus synchronization, embryo transfer (ET) is the third-most commonly used reproductive technology (Cowan, 2010). Embryo transfer from one mother to a surrogate mother makes it possible to produce several livestock progenies from a superior female. Selected females are induced to super-ovulate hormonally and inseminated at an appropriate time relative to ovulation depending on the species and breed. The technology is widely used globally in the cattle industry, with more than ½ million embryos transferred annually. Super ovulatory treatment of donor cows enables production of a higher number of transferable quality embryos and higher probability of producing multiple offspring. Variability in the response to super ovulatory treatments seems to be affected by breed, and the dose of exogenous FSH required for super ovulation of Bos indicus cattle is typically 30% less than that for Bos taurus cattle. (Tamrat et al, 2016). However, embryo transfer is still not widely used despite its potential benefits in developing countries this is mainly due to absence of the necessary facilities and infrastructure. An evaluation of country reports FAO (2007). Shows that only five of the African countries providing information (Cote d'Ivoire, Kenya, Madagascar, Zambia and Zimbabwe) use ET technology, all on a very limited scale. The use of ET also been independently reported in South Africa. The first successful embryo transfers in Ethiopia, resulted in the birth of a Holstein-jersey calf at the Adami Tulu Animal Research Center in the beginning of May, 2010 and five more calves had born. In April 2010, eighty frozen embryos that were imported the previous August were implanted in the native cows Lonny (2010). And also Super ovulation of Boran Cattle in Ethiopia has been reported (Degefa et al., 2016).

The Use of embryo transferring technology
Embryo transfer increases reproductive rate of selected females, reduces disease transfer, and facilitates the development of rare and economically important genetic stocks as well as the production of several closely related Journal of Biology, Agriculture and Healthcare www.iiste.org ISSN 2224-3208 (Paper) ISSN 2225-093X (Online) Vol.10, No.8, 2020 and genetically similar individuals that are important in livestock breeding research (Thibier, 2005). Likewise, Embryo transfer is used to increase the number of offspring that can be obtained from valuable female animals and is mostly used in cattle. Embryos for transfer can be produced in vivo (inside the body) or in vitro (in the laboratory). In vivo embryo production using a technique known as MOET (multiple ovulation and embryo transfer) is used for the production of 80% of embryos for commercial purposes worldwide (Schmidt, 2007). Thus, embryo transfer has the potential to bring about genetic improvement twice as fast as AI alone. Moreover, the use of MOET technique could lead to increased selection intensity and reduced generation intervals, resulting in improving genetic gains. However, embryo transfer is still not widely used despite its potential benefits. In developing countries this is mainly due to absence of the necessary facilities and infrastructure an evaluation of country reports (FOA, 2007). The procedures for removing the eggs or embryos from the donor cow and transferring the embryos to the recipient cows are invasive, generally requiring epidural anesthesia. Cows may be subjected to repeated cycles of MOET or ovum-pick-up, (OPU). There is a risk of pain and infection at the epidural injection site, which may extend to the bone and other tissues (McEvoy et al., 2006).

Cloning
Cloning is a powerful technique and potentially it could be used for multiplication of elite animals and minimize the genetic variation in experimental animals. It can be used for the conservation as well as tool for the production of stem cells for therapeutic purposes, as therapeutic cloning. Cloning using somatic cells offers opportunities to select and multiply animals of specific merits (Das et al., 2003). Numerous types of somatic cells are used as donors in somatic cloning; foetal fibroblasts, adult fibroblasts, granulosa cells, hepatocytes, lymphocytes etc. (Campbell et al., 2007). The birth of Dolly in 1996, the first animal cloned from an adult cell, was not universally celebrated. Critics of biotechnology worried that genetically modified livestock would fill the supermarket with identical copies of someone's idea of unnatural perfection Alison (2008). Up to 2004, about 1500 calves had been produced through somatic cell nuclear transfer (SCNT), mainly in Europe, North America, Japan and New Zealand, but also in South America and Asia Heyman, 2005. China produced the first cloned buffalo in 2004 and India followed suit in February 2009. At present the production of cloned animals is at the experimental stage in most developing countries. Figure1: Cloning by SCNT Embryo splitting involves bisecting the multi-cellular embryo at an early stage of development to generate clones or "twins." A 32-cell embryo, for example, might be bisected into two 16-cell twins. This type of cloning occurs naturally (human identical twins result from this process, but fraternal twins do not), but it can also be performed in a laboratory where it has been successfully used to produce clones from a number of different animal species Alison (2008).
Journal of Biology, Agriculture and Healthcare www.iiste.org ISSN 2224-3208 (Paper) ISSN 2225-093X (Online) Vol.10, No.8, 2020   Camel Reproduction Centre at Dubai, UAE . *The nucleus from an udder cell was fused with an enucleated oocyte then implanted into a surrogate mother and developed. **The nucleus from a cumulus cell was injected into an enucleated oocyte then implanted into a surrogate mother and developed.

Semen and embryo sexing
Though these biotechnologies do not dramatically increase the rate of genetic gain, they can increase production efficiency. According to FAO, 2007 at a research level, they are being developed and refined in a number of research institutions in developing countries. However, with few exceptions, they are not widely used by breeders or farmers in developing countries. Sexed sperm is commercially available in several developing countries, including Ehiopia Argentina, Brazil and China (Garner, 2006;Rath, 2008).

In-vitro fertilization
According to Cowan (2010) in case other artificial reproductive techniques fail due to difficulties such as blocked reproductive systems, non-responsive ovaries in the females, marginal semen quality and quantity in the male, and presence of disease, in vitro fertilization (IVF) is used. The fertilization of the sperm and the egg is conducted in vitro (outside the animal's body) at specific environmental and biochemical conditions. Within vitro fertilization (IVF), a technician removes unfertilized eggs (oocytes) from the donor cow's ovaries, usually recovering 6-8 useable oocytes. The oocytes mature in an incubator and are fertilized with sperm. The resulting zygotes incubate and develop in the laboratory before being placed into the recipient cow. Thus, the IVF procedure for bovine embryos consists of three steps. first, in vitro maturation (IVM) of primary, germinal vesicle-stage oocytes collected directly from the ovaries of donor females, second, IVF by combining in vitro matured oocytes with in vitro capacitated sperm cells and third, in vitro culture (IVC) of presumptive zygotes to stages of development that allow them to be transferred to female recipients Rajesh (2015). For IVF in cattle, the percentage of live offspring per transferred embryo is 45-60% (Chavatte-Palmer et al., 2012). These embryo transfers provide a complete set of new genes and greater genetic gains over that obtained with artificial insemination, where only the paternal half of the genome can be introduced. Supplying embryos from slaughter house oocytes for twinning programmes to increase calves without increasing the number of cows.

Nanotechnology
Nanotechnology is recent advancement in cellular and molecular biotechnology. It has an enormous potential to revolutionize agriculture and livestock sector. This technology allows researchers to handle biological materials and media in minute quantities usually nanoliters or picoliters. In addition to its applications in cellular biology, biotechnology, theraputic medicine and genetics, it might be useful technique in farm animal breeding and reproduction. Micro fluidic and nano fluidic (Schuster et al., 2003;Eijkel and Berg, 2005) are recent tools to simplify traditional procedures of in vitro fertilization (IVF) and in vitro embryo production (Suh et al., 2006). More recent reports have demonstrated the utility of microfluidics in isolation of motile sperm without centrifugation (Schuster et al., 2003). Oocyte manipulation under in vitro condition can also become feasible with advent of this technique (Beebe et al., 2002). Glasgow et al., (2001) first established that manipulation and movement of an embryo in a microfluidic environment. It can also be used in sorting of sperm and eggs, these systems control the flow of liquids or gases through a series of micro and nanoscale channels and valves, which is assisted with computer circuit for data analysis. Nanotechnology has its application in genome mapping and sequencing furnishes a hope to identify gene sequences that relate to commercially valuable traits such as disease resistance and leanness of meat. By including probes for these traits on biochips, breeders will be able to speedily identify elite breeders and screen out genetic diseases. In farm animal breeding heat detection can be done by implanting a nanotube (O'Connell et al., 2002) under the skin to detect the changes in the level of estradiol in the blood. The signal from this sensor will be incorporated as a part of a central monitoring and control system to actuate breeding.

Laser technology
Laser effects on sperm motility parameters, improvement of oocyte maturation and characterization of semen in livestock have been reviewed (AbdelSalam and Harith, 2014). Several application of laser had been reviewed as assisted techniques of reproductive technology to benefit the energy from different types of laser to excite either sperm of oocyte to improve their competence toward fertilization. Also, they mentioned the promising types of laser and wave length in the applications of improving semen parameters either pre-or post-thawing, oocyte maturation for IVF, and avoid the bacterial contamination shorter wavelengths, e.g. λ= 532 nm and λ= 405 nm is promising and more reasonable than longer laser wavelength for bio simulative purposes because they will be better absorbed by the cellular chromophores. The limited publication in this new field reduces the awareness and the speared of such technique in routine field work. SUMMARY: Review was done on potential of reproductive technology to improved ruminant production in Ethiopia. Reproductive technology encompasses all current and anticipated uses of technology in animal reproduction, including assisted reproductive technology, contraception and others. The aims of these reproductive technologies were initially to speed up the genetic improvements of farm animals by the increase of offspring of selected males and females and the reduction of the generation intervals. research into physiology and embryology has provided a basis for the development of technologies that increase productivity of farm animals through enhanced control of reproductive function. animal reproductive technology represents an expanding collection of rapidly developing disciplines in science and information technologies. the livestock provides many opportunities to utilize these disciplines and evolving competencies. artificial insemination, synchronization, embryo transfer, in vitro fertilization, cloning, transgenic and genomics all are components of the tool box for present and future applications. individually, these are powerful tools capable of providing significant improvements in productivity. combinations of these technologies coupled with information systems and data analysis will provide even more significant changes in the next decade. various techniques have been developed and refined to obtain a large number of offspring from genetically superior animals or obtain offspring from infertile (or sub fertile) animals. to take full advantage of the benefits of assisted reproductive technologies, one must understand the basic physiology of the female and male reproductive systems. from those types of reproductive technology, artificial insemination, estrous synchronization and fewer amounts of multiple ovulation and embryos transfer are now implementing in Ethiopia. CONCLUSIONS: Assisted Reproduction Technologies (ART) in farm animals is recently receiving renewed attention. Reproductive Technology can be used to meet the increasing country desire for animals' products and to overcome reproduction failure in high producing animals. On the other hand, artificial insemination is the most commonly used and valuable reproductive technology and the practice in cattle goes back to 1938 in Ethiopia, Despite, the efficiency of AI delivery system in the country, has remained at a very low level. Estrus Synchronization the second most important technology in the country to improve productivity of the animal it used to bring a group of female for parturition: decrease labor, and financial resources, decrease calving period reduce calving season more uniform weaning weights. Reduce or eliminate estrus detection needed for artificial insemination. Various estrous synchronization protocols are available in the world. Some commonly used estrous/ovulation synchronization protocols in dairy cattle includes use of prostaglandin (one shot method and two-shot method) and progestin. The most important reproductive technology after AI and estrus synchronization is embryo transfer (ET) is third used reproductive technology in Ethiopia to improve ruminant productivity.