Review on breeding objective and practice of dairy cattle production in Ethiopia

Contents

Abstract

Introduction

Dairy cattle production system in Ethiopia
The rural small holder (crop-livestock) dairy production system
Pastoral and agro pastoral dairy cattle production system
Urban and peri-urban small holder dairy production system
Commercial dairy cattle production system

Reproductive and Productive Performances of Dairy Cattle
Age at First Service
Number of service per conception
Age at first calving
Calving interval
Lactation length and milk yield

Breeding practice of dairy cattle
Natural mating
Artificial insemination

Breeding objective of dairy cattle

Conclusion

References

Abstract

This review was aimed to indicate the dairy cattle production system including small holder, pastoral and agro pastoral, urban and per urban and intensive dairy cattle production system, breeding practice including mating system (natural mating and AI), breeding objective and reproductive and productive traits of dairy cattle in Ethiopia. Now in Ethiopia most farmers use natural, unplanned and uncontrolled mating system by using breeding from communal grazing and a few farmer use AI for improvement of breed and production by upgrading the genetic makeup of indigenous breed of cattle. Therefore, in Ethiopia, there is a need to use breeding objectives in line effective breeding policies for both AI and natural service for sustainable and effective animal breeding practice. There should be appropriate animal breeders, policy designers and stalk holders have to give due attention to transform the existing traditional breeding practices targeting towards dairy productivity and production with careful consideration of genetic conservation of local cattle breeds .

Keyword; Breeding objective, Breeding practice, Dairy cattle, Ethiopia

Introduction

Agriculture is the major economic activity in Ethiopia. Among the agricultural activities, livestock sector plays a significant role in the economic, social and cultural development of the agrarian community . Ethiopia holds the largest livestock population in Africa which is estimated to be about 59.5 million heads of cattle, 30.7 million sheep, 30.2 million goats, 8.43 million donkeys, 2.158 million horses, 0.409 million mules, 1.2 million camels, 59.49 million chicken and 5.90 million beehives (Central Statistical Agency (CSA, 2016/17 ). The livestock sector is mainly of smallholder farming system having multipurpose use and contributes about 16.5% of the national Gross Domestic Product (GDP), 35.6% of the agricultural GDP, 15% of export earnings and 30% of agricultural employment (Duressa et al.,2014; Metaferia et al., 2011). Livestock also provide a significant nutritional supplement to vulnerable groups, increase the resilience of smallholder households in the face of food crises, and help to maintain traditional social safety nets (Randolph et al., 2007) and the sub-sector has an enormous contribution to national economy and generating income to farmers, creating job opportunities, ensuring food security, providing services, contributing to asset, social, cultural and environmental values, and sustain livelihoods (Solomon, 2003; Sintayehu et al., 2010; CSA, 2017).

The dairy sector is also a major pillar in the socio-economic standing of sub-Saharan Africa (SSA); including Ethiopia for functioning both food security and income generation roles, particularly at small household level. As indicated in (CSA, 2016/17) most of the cattle in the country reared by the agrarian community are of native breeds/ecotypes which is about 98.2 percent of the total cattle present in country level and the rest are 1.62 crossbreed and 0.18 are exotic cattle breeds. The distribution of native cattle populations across the different agro-ecologies of the country provide various options for tangible and non-tangible use of livestock products to the smallholder farmers and pastoral communities (CSA, 2016/17). And also according to CSA 2016/17 cattle’s are mainly kept for milk, draught power, and breeding and beef purpose and have also high contribution of milk production performance annually with about 3.1 billion litters with 1.37 liter milk yield per day by having 6 month average lactation length per a single lactation.

Even though Ethiopian indigenous cattle are well adapted to the tropical environment producing and reproducing under stresses of high degree of temperature, high disease prevalence and low level of nutritional status, their production performance was low due to their genetic makeup, low level of inputs, and traditional husbandry practice besides environmental stress ( Azage et al., 2010). According the report of Godadaw, M, et al., 2015, the breeding dairy cattle are mostly natural mating and there is also the use of AI in a small amount for breeding purpose and increment of the level of the production of the dairy cattle. Despite the importance of this subsistence sector, scanty information is available on the status of the national dairy cattle genetic improvement program that guide policy makers, development planners and breeders to redesign appropriate breeding practice that respond to the current scenarios in Ethiopia (Kefena et al., 2011).There for it is important to review breeding practice of dairy cattle for improving the blood level, production and reproductive performance of indigenous breeds by reviewing dairy cattle production system, breeding objective and practice of dairy cattle in Ethiopia

Dairy cattle production system in Ethiopia

The latest estimate of Ethiopia’s cattle population is estimated to be 59.5 million, out of this total population 55.5 percent and 44.5 percent female and male cattle population respectively with having 98.2 percent indigenous, 1.62 percent cross and 0.18 percent exotic breeds respectively (CSA, 2016/17). Most dairy cattle production system in Ethiopia depends on low producing indigenous breeds of cattle. The existing dairy cattle production systems in Ethiopia belong to any of the following four major livestock production systems: rural smallholder (mixed crop–livestock) production, pastoral and agro–pastoral production, urban and peri-urban smallholder dairy production and specialized commercial dairy production systems.

The rural small holder (crop-livestock) dairy production system

The Ethiopian highlands possess a high potential for dairy development and occupying the central part of Ethiopia, over about 40% of the country (approx. 490.000 km2) and are the largest of their kind in sub-Saharan Africa (Tedla et al, 1989). This production system predominantly exists in the highland agro–ecological zone, where the climate favors both crop cultivation and livestock rearing as complementary enterprises and major types of farm animals except camels are found and farmers usually prefer to keep mixtures of farm animal species.

The milk production in this production system depends on with high amount of indigenous breeds and small amount in cross breeds of cattle. The majority of milking cows are indigenous animals which have low production performance with the average age at first calving is 53 months and average calving intervals is 25 months. In this farming system all the feed requirement is derived from native pasture and a balance comes from crop residues and stub grazing.

Pastoral and agro pastoral dairy cattle production system

This system exists in the vast lowland areas of the country where arid and semiarid agro-climates dominate. This system is characterized by sparsely populated pastoral rangelands, where subsistence is mainly based on livestock and livestock products except in agro–pastoral areas, where some crops are produced for both subsistence and the market.

In the pastoral system, relatively large herds of cattle are grazed on communal and public land. Because of seasonal scarcity of feed and water, cattle trek over long distances. Pastoralists are unable to settle and take advantage of available production technology.

Agro-pastoralists own sizable pieces of land and practice integrated cop-livestock production. In this system, crop residues are utilized when feed is scarce but nutritional inadequacies remain. Transfer of technology is not easy and in spite of this in a few countries farmers in this system adapted improved technologies.

The livestock husbandry in this system is dominated by goats, cattle, sheep, and camels. The main source of food is milk, so pastoralists tend to keep large herds to ensure sufficient milk supply and income (IBC, 2004).

Urban and peri-urban small holder dairy production system

Urban dairy cattle production systems in general are located in cities and/or towns for production and sale of milk, with little or no land resources, using the available human and capital resources mostly for specialized dairy production under stall feeding conditions (Azage et al 2013). By virtue of their location, urban producers are not expected to have access to agricultural or pasture land, as the operation takes place within cities and as a result, they are forced to buy feed (Zegeye 2003). Peri-urban dairy systems are located in rural areas or at the periphery of the urban areas which have relatively better access to urban centers in which dairy products are highly demanded (Azage et al 2013).

These systems are contributing immensely towards filling the large demand-supply gap for milk and milk products in urban centers, where consumption of dairy products is remarkably high and they are the main suppliers of raw milk to the processors of different scales (Zelalem et al 2011). Dairying in urban and peri-urban areas creates employment opportunities and provides farmers a chance to use land, labour and feed resources to generate regular income (Gillah et al, 2012).These market-oriented urban and peri-urban systems are emerging as important components of the milk production systems in Ethiopia. The most important benefits are increased income, employment generation, food and nutrition, organic waste recycling and uplifting social status (Gillah et al, 2012). The urban and peri-urban systems are being intensified through the use of crossbred dairy cows, purchased and conserved feed and stall-feeding (Azage et al, 2010).

According to Assaminew S and Ashenafi M, 2015, the average head of Crossbred cows was higher in urban than that of peri-urban dairy cattle production system and the total cattle heads which includes cross and local breeds, Grazing land holding and Land allocated for forages were higher in peri-urban production system.

Commercial dairy cattle production system

This system is a specialized market oriented dairy operation practiced by the state sector and very few private commercial farms. Most of these farms are located in and around Addis Ababa and basically keep exotic dairy stock (Ketema and Tsehay, 1995) and Azage et al, 2000)).

Reproductive and Productive Performances of Dairy Cattle

Reproductive as well as productive performance of animals is influenced by both genetic and non-genetic factors. In dairy animals, reproductive performance affects total milk production and calf crops obtained in the life time of dairy cows. In Ethiopia indigenous cattle’s are the dominant source of milk across all the production systems with the exception of urban and peri-urban dairy system where improved crossbreds have significant contribution to milk production.

The reproductive efficiency of dairy cattle can be measured in several traits, like Age at fist service, number of service per conception, age at first calving, lactation length, calving interval, days open, and average milk yield per day an per lactation.

Age at First Service

According to Gidey (2001), age at first service (AFS) is the age at which heifers attain body condition and sexual maturity for accepting service for the first time . It is defined as the length time between the date of birth and the date of showing first heat in a life time of an individual cows or heifers. According to Assefa et al. (2015) the average age at first service was 40.74 months for heifers of indigenous breed and the average effective age service of local bull is 44.4 months in sidama zone.

On the other hand, the average age of first service for Holestain Friesian cross zebu cattle breed in Northern Amhara was 24.8±6.6 (Mekonnin, A.B., et al, 2015). The age at first calving is lower in exotic and cross breed than indigenous breeds. Management factors especially nutritional status determines pre-pubertal growth rates and reproductive development (Masama et al., 2003). Delay in the attainment of sexual maturity leads to economic loss, due to an additional, non-lactating, unproductive period of the heifer/cow over several months (Mukasa-Mugerwa, 1989).

The variation in AFC between genotype and agro-ecologies is probably due to the difference in management and feeding systems, the effect of non-genetic factors Shiferaw et al.(2003) have also been reported reproductive efficiency of dairy cows is influenced by different factors including genetic, season, age, production system, nutrition, housing and management, environment and disease (Shiferaw etal., 2003).

Number of service per conception

Number of service per conception is the number of services/inseminations required for a successful conception (Menale et al., 2011). It depends largely on the breeding system used and influenced by both genetic and non-genetic factors like season (which related with availability of feed), semen quality and quantity and parity (Gebrekidan et al., 2012).

Table 1; The average number of service per conception of dairy cattle in different location and different breeds of cattle.

Abbildung in dieser Leseprobe nicht enthalten

Age at first calving

The Age at first calving is the age of an individual when first give birth new born in life. First calving marks the beginning of a cow’s productive life and influences both the productive and reproductive life of the female, directly through its effect on her lifetime calf crop and milk production and indirectly through its influence on the cost invested for upbringing (Azage T, et al.,2011 and Tewodros B. 2008). A recent study reported that dietary supplementation of heifers during their period of growth reduces the interval from birth to age at first service and birth to age at first calving(Amin et al., 2013)

Table 2; Average age at first calving of different breeds of cattle

Abbildung in dieser Leseprobe nicht enthalten

Calving interval

The Calving interval refers to the period between two consecutive calving and is a function of a day’s open and gestation length. Since gestation length is more or less constant for a given breed, the number of days open becomes the sole variable of calving interval. Calving intervals have low heritability and can be improved through nutrition and early breeding (Mulugeta et al., 1990).

It is very much important to the breeders because the lowest the calving interval the highest the lifetime calf production. Extended calving interval is one of the major problems that reduce lifetime productivity of dairy herds (Belay D, et al, 2015).

Genetic factors, year and season of calving, nutrition and age of cow are known to have significant effects on calving interval (Assemu T. 2015). In an optimum combination of good management and sound physiological condition of the cow the reasonable short calving interval is 12-13months.The average calving interval for Holestain Friesian cross zebu breed in and around Mekele was 401.5±73 days(Mekonnin, A.B., et al, 2015).

Days open up to conception is defined as the interval from calving to the day of conception, which includes the postpartum anestrous interval and service period. Days open is the most variable determining component of calving interval and is mostly influenced by the length of time for the uterus to completely involutes, resumption of normal ovarian cyclist, occurrence of silent ovulations, accuracy of heat detection, management decisions on how soon to rebreed following parturition, fertility of a bull or semen and efficiency and/or skill of inseminator. The average days open till conception of dairy cattle was 155.7±1.72 days. Feed shortage, silent estrus and lack of proper heat detection might have contributed considerably to the long days open reported in their study (Belay, et al., 2012).

Gestation Length (GL): The GL is the period between the date of fertile service and the date of calving. This period is almost invariable within individual in a breed or type. Gestation length, which is more or less constant, varying slightly due to breed, calf sex, litter size, dam age, year, and month of calving, and little can be done to significantly manipulate the gestation length (Asheber S. 1992, Addisu B. 1999, Giday Y. 2001 and Fikrie L, et al, 2007).

Lactation length and milk yield

Lactation length is the time period through which a cow continues giving milk in one milking time. The overall lactation length of indigenous cattle was 203.54 days (Asefa. et al., 2015), 7.29 month (kedija H, 2007), 9.8 month (Adebabay K. at al., 2012), 9.13 month (Mulugeta A and Belayneh A, 2013) and 6month (CSA. 2013). The standard period of 305 days has been chosen because this is approximately the normal lactation length of cows calving at intervals of 12 months. In tropical cattle, restricting the lactation records to 305 days would have less effect, as few cow’s milk for more than 305 days. Lactation length can be affected by shortage of feed, poor management practices, different in production system, age and breed of animal. The average milk yield of indigenous breeds of cattle per day was 1.25 liters (Asefa. et al., 2015), 4 liters (ILDP. 2004), 1.82 liters (Adebabay K. at al., 2012), 1.69 and 1.86 liter in first and second lactation respectively (Zewdu W. 2004), 1.67 liters (Mulugeta A and Belayneh A, 2013) and 1.32 liters (CSA. 2013) which was also affected by different factor including management, climatic condition, disease problem, availability of water and feed, lactation cycle and parity of cows.

Breeding practice of dairy cattle

Mating in the context of animal breeding means pairing of female and male animals for the Purpose of reproduction on a farm using natural or artificial (AI) methods (Willam and Simianer,2011). Similarly Godadaw, M; et al., 2015 reported that the breeding practice of Dairy cattle’s are mostly natural mating in which bulls can be used for either free mating(uncontrolled mating) in the range land or controlled mating and the use of AI in a small amount were applied in dairy cattle breeding for production or reproduction purpose.

On the other hand, Gebremichael, D., 2015 also reported that mating of dairy cattle in central Zone of Tigray was natural mating (35%), AI without synchronization (42.77%) and AI with synchronization (22.22%) which was considered to better in Ethiopia concerning technology transfer of breed improvement and trait preference of dairy cattle in that area was ranked as milk yield, fertility, body weight, feeding behavior, temperament, color and disease resistance ability.

An efficient, systematic and operational breeding strategy is necessary to bring about any substantial improvement in the dairy sector. Development of the dairy sector in Ethiopia as in any other developing countries can further be augment with the selection within the native cattle besides crossbreeding (Yilma, 2011).

However, any formal pedigree and performance recording systems are virtually non-existent with the traditional rearers in most of the tropical countries, thus under those condition the only option left is to select animals based on their phenotypic traits like body size, udder size etc. (Bebe, 2003). For effective breeding practice, one should consider techniques and options of improving the genetic performance of cattle.

Natural mating

The use of bulls for natural service remains widespread in Ethiopia. Uncontrolled natural mating is the dominant form of animal breeding system practiced under extensive husbandry in rural areas. As indicated in a study by Mekonnen et al. (2012) and Azage et al. (2013) panmectic mating predominates under the extensive livestock husbandry system especially in the rural areas.

A study made by Desta (2002) indicated that many farmers in Ethiopia prefer natural mating as the conception results from the AI services is not successful. A study made by Zewudu (2004) reported that majority of the farmers in Dembia and Fogera districts obtained their replacement (breeding) animals from their own farm and sometimes from their relatives and neighbors. In the rural lowland areas of Metema, majority farmers breed their cow with any available bull in the village. This is because most of the farmers do not own breeding bulls and they use bulls from neighbors or use open mating in the communal grazing land (Azage. 2013).

According Godadaw. M; et al., 2015 In natural mating bulls can be used for either free mating in the range land or controlled mating .In free mating in the range land bulls can carry out heat detection and cows in heat are mated by bulls several times during each heat period and in controlled mating heat detection is carried out by the owner of the cows (farmer) and cows mated once or twice in each period. Also According to the report of Asrat et al. (2013) under mixed crop-livestock production system of Boditti woreda most of the households depend on natural mating using native bulls while the rest a small number of households depends on AI.The main source of breeding bull for natural mating was own herd, village bull and neighboring bull in the range land of the community (Gebremichael, D., 2015).

Artificial insemination

Artificial insemination (AI) is a process in which sperm is collected from male animals and artificially introduced into the female reproductive tract for the purpose of fertilization (Webb 2008). Sperm is stored and from one ejaculate of a bull around 200 to 300 portions of semen can be harvested (Niemann 2006, Willam and Simianer 2011).

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; Geberemedhin, 2005; Holm et al., 2008). AI also plays important role to increase the yielding capacity of cows and is the appropriate and cheapest way of genetic improvement.

The availability of accurate heat breeding records like breeding dates, pregnancy rates, inter-estrus intervals and days to first service used to monitor fertility (Sinishaw, 2005).Poor conception rates due to poor heat detection and inefficiency of AI technicians, Dissemination of reproductive diseases and poor fertility rates if AI centers are not equipped with appropriate inputs and are not well managed (Desalegn, 2005) and High cost of production (processing and collection), Storage and transport of semen (Pope, 2000) was the major limitation of AI .

Breeding objective of dairy cattle

Breeding objective is defined as the reasons for which animals are specifically bred for, assuming that farmers have made a deliberate choice to genetically improve the next generation of animals in terms of their performance in relation to their parent generation. The focus is therefore on one or more traits. The objectives are likely to be affected by the cost of production and the revenue from product sales related to a genetic change in the target trait. Cattle have multipurpose functions. These include traction, milk production, income generation, manure, reproduction and meat production (Zewdu et a, l 2006).

The main breeding objective traits in dairy cattle was obtaining better milk yield (Godadawu D, et al, 2015 and zewude 2004) and in addition increasing milk yield, obtaining of good breeding bull, and plough ox, good mothering ability and shortening of calving intervals were also aimed as breeding objective (Godadawu D, et al, 2015) and the other traits important for obtaining breeding objectives were Draught power, Coat color, Mothering ability, butter yield and Getting marketable animals for better improvement and production.

Similarly Cattle trait preference of the farmers in Dembia, Fogera and Wogera Distrct of Northern Amhara region of Ethiopia for achievement breeding objective was ranked sequentially as milk yield, adaptation, growth rate, draught power, breeding ability, cow coat color and better fat yield (Godadawu D, et al, 2015).

Conclusion

Agriculture is the main economic activity in Ethiopia in general and livestock is also the major among other agricultural activity. Ethiopia holds the largest livestock population in Africa which is estimated to be about 59.5 million heads of cattle, 30.7 million sheep, 30.2 million goats, 8.43 million donkeys, 2.158 million horses, 0.409 million mules, 1.2 million camels, 59.49 million chicken and 5.90 million beehives. Dairy cattle and livestock make an essential contribution to agriculture, food and rural development. Cattle comprise the majority of the livestock population in Ethiopia and are reared across all the agro-ecologies. However, the productivity of cattle did not much their number due to prevalence of disease, shortage of breed improvement program, uncontrolled mating or breeding practice, shortage of feed, traditional production system and poor reproductive performance. By addressing these constraints to all stalk holders including the owners or farmers and designing appropriate mating or breeding systems is the best option in improving breeding practice of dairy cattle in Ethiopia.

Breeding practice need to involve farmers, stalk holders in the sector, government policy, the existing breeding practices, production system, management systems and their trait preferences to upgrade the reproduction and production traits of dairy cattle. Exploring indigenous knowledge of managing the herd, setting of breeding objectives and finally designing appropriate mating systems with full participation of farmers is very important in improving dairy cattle production. Therefore, Most of the livestock production system in Ethiopia is traditional based with low production potential of indigenous breeds of cattle with relation of awareness of farmers. So, farmers should train different aspects of improving cattle productivity by considering the reproductive and productive traits for improvement of sustainable dairy cattle production and productivity.

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