The productivity and resilience of the indigenous chickens in the tropical environments: improvement and future perspectives

ABSTRACT

The poultry population in Africa is mostly composed of local or indigenous chickens appreciated for the unique taste and texture of their meat. However, with the ever-increasing population growth, the free-range or backyard poultry farming system is no longer adapted to supply people with protein requirements. Crossbreeding local hens with an improved rooster weakens the thermotolerance and disease resistance of the offspring in African areas. In this context, the available breeds need to be preserved. The improvement of their productivity should be actualized through the implementation of a sustainable production programme that is simple and less expensive for the farmer, taking into account: feeding, habitat and chicken care. Scientific research should invest more time on the identification and characterization of all available breeds or chicken ecotypes allowing us to know production performances and their nutritional needs. Feeding with locally available resources, vaccination and use of indigenous medicine requiring training of farmers are essential perspectives. This paper focused on the productivity and resilience of indigenous chicken ecotypes in various African tropical environments and some essential factors to improve the birds. For this, a critical analysis was made based on the available data on the birds from research databases.

KEYWORDS:

• Indigenous breeds
• ecotype
• management
• free-range
• backyard system

Implications

The genetic approach (introduction of exotic cocks for crossbreeding with local hens) has always been presented as the only alternative to improve the productivity of indigenous or local chickens in rural areas. However, the genetic potential of these birds in rural areas does not seem to be fully exploited owing to inappropriate production system (scavenging production system). Apart from crossbreeding, adequate practices could be implemented to improve productivity. But, to achieve this, data on the productive performance of indigenous chickens are required.

1. Introduction

Indigenous chickens contribute to the security of cash income and are an excellent source of animal protein in rural sub-Saharan Africa (Gebreselassie et al. 2015; Raphulu and van Rensburg 2018). In tropical areas, most of the chickens comprises indigenous chickens (MALF 2015). However, these chickens are characterized by poor growth rate and low productivity (Mbuza et al. 2016). This poses a problem of security in the supply of animal proteins to the population. For example, exotic birds reared in intensive systems in modern farms have a higher genetic potential for growth than the indigenous ones. Gebreselassie et al. (2015) have recorded poor laying performance compared to exotic chickens under the same farmers’ management practices in Ethiopia. However, one hypothesis would be that even if these chickens present low feed efficiency and growth rate, their growth potential may not be fully exploited (MINAGRI 2012; Padhi 2016). Production performance is influenced by genes, nutrition and health (Dana et al. 2010). Mahoro et al. (2017) suggest the improvement of productivity without altering their morphological and environmental characteristics. This emphasizes the preservation of these types of chicken gene pool while looking for the key factors to improve its productivity. Most of the world's poultry population, made up of indigenous breeds (about 80%) remain unknown to the scientific community, with unknown risk status for 40% of them (Besbes 2009). Thus, the production systems and identification of the existing local chicken ecotypes are highly suggested. It is necessary to collate information on the productivity, characterization, geographical distribution and rearing system adapted to each ecotype. This paper reviews the production constraints and key factors needed to improve the productivity and resilience of indigenous chickens and provides substantial information on ecotypes in different African rural areas.

2. Methodology

To achieve the objective of the review, a synthesis of the available knowledge on the different breeds and production strategies of local chickens have been made and a critical analysis of the constraints that hinder the improvement of local chicken productivity in rural areas. Also, a practical model simple to be implemented by farmers is proposed and further the focus is on the channel of dissemination of information to farmers (training). Thus, as part of the critical analysis, this review provides information for researchers, farmers, third party and policy makers (Gough et al. 2019). Relevant studies (articles and reports) were found by using research databases such as Scopus, Web of Science, PubMed, Science Direct, Directory of Open Access Journals (DOAJ), PLoS ONE, JSTOR, Google search, Google Scholar and the Wiley Online, FAO and World Bank Databases, country online databases, (Younger 2004; Cronin et al. 2008). Keyword searches method was also used to identify literature. Key words such as indigenous breed, local breed, ecotype, climate resilience, heat stress, outbreak diseases, productive and reproductive performance, food security and feed cost are among those used in search engines (Younger 2004; Ely and Scott 2007).

3. Importance and some constraints of indigenous chicken production

Studies have shown that 70%–80% of the chickens, even more, are of indigenous strains in sub-Saharan Africa (Gueye 1998; Goodger et al. 2002; MALF 2015). Local chickens play essential roles in the economic and nutritional welfare of poor rural households (Bwalya and Kalinda 2014). In addition to being a source of quality animal protein, it contributes to the provision of income, gift payments and various traditional, religious and other customs (Malatji et al. 2016). In that way, the consumption of indigenous chicken eggs and meat is constantly increasing. The special quality of meat is relative to its taste, flavour and aroma (Escobedo Del Bosque et al. 2020), which contradicts those of the exotic fast-growing strains (Mazimpaka et al. 2018). However, the productivity of indigenous chickens in rural areas is very low (Mazimpaka et al. 2018). Their production is faced with several constraints, which are the availability of feedstuffs and its high cost, climate challenge inducing frequent diseases and high mortalities in the flock and poor feed efficiency (Magothe et al. 2012; Mahoro et al. 2017). Newcastle disease appears to be the most prevalent viral disease in indigenous chickens in rural areas (Lwelamira and Katule 2005). The other important aspect regarding the problem of mortality is the non-negligible mortalities due to predation and trampling by vehicles (Babiker et al. 2009). Very often, this reality is obscured by literature. This situation is critical because 40%–80% of dead chickens are often recorded in early life (6–8 wk of age) (Kingori et al. 2010). Faced with all these constraints, reviewing the chicken farming system is essential. In practice, chickens are raised in different production systems.

4. Lower feed efficiency of birds

Feed conversion to meat and eggs of local chickens needs to be improved in hot and humid climates. The low growth of local chickens leads to lower yields and lower profits for farmers. The feed conversion ratio of chickens describes the feed utilization efficiency and is measured by the ratio of feed consumption and body weight gain of the bird in a certain period of time. The lower ratio is, the better it is and indicates the efficient use of feed compared to an overfeeding or underfeeding expressed by an increased feed conversion ratio (Yi et al. 2018; Bai et al. 2022). Nevertheless, the feed conversion ratio cannot be used to measure feed economic efficiency without considering the cost of the diet. Feed economic efficiency is evaluated by multiplying the feed conversion ratio and feed cost (Bai et al. 2022). Feed efficiency is generally evaluated by feed conversion ratio, particularly feed economic efficiency. A suitable feed formulation for which feed conversion ratio and feed cost is the lowest. Feed formulation aiming at feed efficiency is crucial for improving the chicken growth. It is desirable to efficiency or improve the feed conversion to meat in local chickens. However, there are scientific concerns associated with this. Genetic selection for feed conversion ratio is difficult since this parameter is strongly correlated to feed intake and body weight gain.

For this reason, residual feed intake appears to be the most appropriate criterion for the genetic improvement of energy efficiency in chicken breeding in many studies (Yuan et al. 2015; Begli et al. 2016; Xu et al. 2016). It expresses the difference between the predicted and the actual feed intake based on multiple linear regression equations of the requirements for production and body weight maintenance in a certain period (Wen et al. 2018). It is important consider the crucial problem of heat stress in chickens in the tropics which affects feed utilization efficiency. It contributes to reduced bird performance and the increase in the mortality of chickens (Oke 2018; Oke et al. 2020; Wasti et al. 2020; Kpomasse et al. 2021). In different parts of Africa, heat stress occurs mainly through seasonal climate fluctuations (Oke et al. 2017; Ahaotu et al. 2019; Oke et al. 2021). Despite their advantages (their strengths, resistance to the harsh environmental conditions, and meat quality), indigenous chicken’s poor growth reduces interest get in these chicken ecotypes. Interestingly, 6.03% of local breeds risk extinction (FAO 2021).

5. Factors affecting productivity of local chickens

The productivity of the chickens is affected by the production system, which also affects the feed distribution and health care received by the chickens. Generally, three main production systems are distinguished (free-range extensive, semi-intensive and intensive) to which a fourth (backyard extensive) is often added based on the level of biosecurity and marketing of birds and their products (FAO 2008; Samanta et al. 2018):

• – free-range extensive: involves about 80% of poultry. Chickens can scavenge for feed over a wide area without or not housing care;

• – backyard extensive: poultry benefits to housing care at night, allowed free-range during the day and usually received a handful of grain (maïs or other) in the morning and evening to supplement scavenging;

• – semi-intensive: this system is a combination of two production systems: extensive and intensive systems. Chickens are confined to a particular area with access to shelter. The chicken run is fully fenced. They are protected by a shelter where feed and water are available and where they are not exposed to bad weather (rain, wind, wild animals);

• – intensive: is a system where total confinement of birds, total dependence on their owner for all their requirements and invested capital. The productivity of the birds in this is higher than in the extensive system. It is mostly used by medium to large-scale commercial enterprises. It can be three types: Deep litter system, Slatted floor system and Battery cage system.

Menge et al. (2005) reported three systems of chicken production in Kenya which are scavenging (free-range or extensive), semi-intensive, and intensive systems (Mujyambere et al. 2022). ‘Backyard’ or ‘village level’ poultry production system with minimal biosecurity is considered a free-range production system in which the birds scavenge around the house or in the backyard during daytime (FAO 2004). They are sometimes fed household wastes or kitchen scraps like raw vegetables, cooked rice, insects, larvae, seeds, and so on (Samanta et al. 2018). This rearing system plays a significant role in the rural household by providing protein (Tashi and Dorji 2014), poultry products used as gifts or sacrifices during festivals or traditional ceremonies (Hamilton-West et al. 2012), income or ready cash (Sambo et al. 2015), financial security to ensure children's school expenditure and other expenses (FAO 2008). It takes a different form in urban areas called ‘urban backyard farming’ or ‘hobby/peridomestic/fancy poultry’, where chickens not only play a role as a homemade source of food but also as fun, hobby or companion pets (Samanta et al. 2018). Since birds scavenge for feed in rural areas and rarely benefit from the kitchen and other household wastes (Mbuza et al. 2017), feed efficiency is poor even though few inputs are used (Bwalya and Kalinda 2014; Mahoro et al. 2017). Finally, three factors could be considered affecting indigenous chickens’ low productivity: genotype, poor feed conversion efficiency and low adoption of modern technologies (Kingori et al. 2010). In order to understand how to improve the productivity of indigenous chickens, it is essential to know more about the characteristics of their production system.

6. Characteristics of scavenging system of production of local chicken

The scavenging rearing system is predominant in rural areas (Khobondo et al. 2015), where the chickens lack housing and are exposed to various weather conditions. About 80% of the chickens are reared in such a management system. Low input is used: human intervention, veterinary drugs and feed is of poor quality and quantity and does not meet the nutritional requirements of the chickens (Mukarumbwa et al. 2021). Sometimes they eat everything they find in the bush, such as seeds, insects, earthworms, and grasses (Birech 2002). Grains and kitchen scraps or household wastes are thrown on the ground before they go into the bush or on their way back from the bush in order to meet the nutritional requirements (Mahoro et al. 2017). Other challenges that hamper local chicken production and increase their mortalities or loss in productivity involve: predators, thieves and information on poultry rearing (Moussa et al. 2019). As a result, these characteristics induce the low productivity of local chickens. Then, enhancing chicken production needs the improvement of production management practices (Gueye 1998; Abdelqader et al. 2007). Some studies have suggested improving management practices and enhancing the productivity of genotypes (Pym 2013; FAO 2014; Padhi 2016; Wong et al. 2017). Using an extensive production system is no longer advisable with the global population explosion. In this context, it will be necessary to rejig an adequate model of a livestock production system that is less expensive but more profitable. However, little attention is paid to research on local chickens (Obanla et al. 2012; Oke et al. 2014; Oke et al. 2015; Conteh and Sesay 2019). Feed accounts for most of the cost of production in indigenous chicken enterprises in tropical climates (Odah et al. 2019). Even if they survive on an extensive production system based on the use of few inputs, this system is not amenable to sustainable production to face the challenges of food and nutritional security in Africa. Considering its many adaptive characteristics to different agroecological zones in the tropics with appreciable immunity from endemic diseases (Dunya et al. 2015), the genetic capital of these chickens should be preserved while acting on other factors such as feeding, housing and management strategies.

7. Preservation of local chicken ecotypes

Indigenous chickens are more adapted to tropical environments due to the presence in their gene pool of seven to nine major genes which preserve them for negative effect of heat stress (Ajayi 2010). For this reason, the objective will not be primarily to focus here on the genetic approach. Also, crossbreeding with exotic chickens proved to be an unsustainable strategy. Due to their low productivity, there is a lack of interest in raising local chickens on a large scale (Yusuf et al. 2014; Idowu et al. 2018a). Nevertheless, in many projects aimed at improving rural household livelihoods of communities, development organizations working to improve local chicken farming in rural areas have failed to make the right decisions or implement adequate strategies to preserve chicken genetic stocks. This has contributed to the risk of extinction of some local breeds (FAO 2021) and the loss of some beneficial traits associated with these ecotypes. Before improving a chicken strain, its performance should be known, whereas data are scarce for many indigenous ecotypes. Attempts to introduce exotic breeds to smallholders undertaken in the past have not been successful in Sub-Saharan Africa because of the high cost of production inputs (feed, veterinary products, etc.) and the management issues (Sonaiya and Swan 2004). Also, it is necessary to make an important observation that these exotic breeds were developed in temperate areas and are therefore less adapted to the tropical climate (Abioja and Abiona 2021). Indigenous chickens are valuable gene pool. Thus, while waiting for more data on their genetic makeup, it is necessary to preserve this this large reservoir of genes.

8. Lack of information on the nutritional requirements of the birds

Due to their low productivity (Anderson et al. 2018), indigenous chicken production has received attention from farmers and scientists. There is a lack of information on the local ecotypes. Apart from management practices, feed formulation and distribution are essential to such a farming system. The problem of feeding local chickens arises from the lack of information on their needs in different sub-Saharan African countries (Chah et al. 2015). In order to formulate a feed capable of meeting the nutritional requirements of chickens, it would be necessary to know these requirements. This represents a significant challenge, owing to the lack of information about it. However, feed cost is crucial to poultry production cost (Willems et al. 2013). Farmers need knowledge of geographical distribution, characteristics and current production practices to adopt an adequate management technic in farming indigenous chicken genetic resources at local, national and even regional levels.

9. Indigenous ecotypes in sub-Saharan African areas

Local chicken is preferred over exotic ones because of the flavour and taste of its egg and meat (Raphulu and van Rensburg 2018). Due to the preponderance of local strains (Besbes 2009), adequate management of the birds is needed. Identifying the different breeds or ecotypes and the statistics of their population sizes, geographic distributions (habitats) and genetic diversity will benefit their improvement (Moula et al. 2012). The term local chicken or indigenous chicken is referred to chicken mostly produced in free-range (extensive) system with low input (Manyelo et al. 2020). According to same authors, such birds are often described and grouped according to geographical location or phenotypic characteristics but sometimes classified into ecospecies. The term ‘ecotype’ is used to designate a population within a breed that is genetically adapted to a specific area or habitat (FAO 2013). Over the years, indigenous chicken breeds, as a valuable genetic resource, incomparable to exotic strains (Padhi 2016), have been selected for their characteristics (phenotypes, adaptation to the environment and resistance to diseases) (Mpenda et al. 2019). This has led to a wide range of chicken breeds and ecotypes worldwide (Di Lorenzo et al. 2015). However, the lack of data on the productive performance of chickens makes it challenging to develop sustainable egg production programmes. According to climatic conditions, indigenous chicken exhibits a wide phenotypic variability in plumage, shank, eye, earlobe, comb, skin, feather distribution and body size (FAO 2010; Apuno et al. 2011; Manyelo et al. 2020). As a result, the breed’s characteristics vary from one area to another in African environments. In South Africa, five ecotypes of native chicken breeds can be distinguished: Venda, Ovambo, Naked necked (Kaalnekke), Potchefstroom Koekoek and Boschveld chicken (Van Marle-Köster and Casey 2001; Mammo et al. 2008; Manyelo et al. 2020). The Ovambo breed originated in the northern part of Namibia and Ovamboland in Africa (Grobbelaar et al. 2010). Boschveld is a cross between three indigenous chickens such as Matabele, Ovambo and Venda. It is essential to highlight that the indigenous breed Naked necked, prevalent, is present in other African countries: Kenya, Uganda, Ethiopia, Cameroon, Nigeria and Burkina Faso (Grobbelaar et al. 2010). In the same vein, the native chicken breeds or ecotypes of some African countries are presented in Table 1.

Table 1. Local chicken breeds or ecotypes from some African countries.

African countries	Native chicken breed or ecotype	Reference
Northern Africa
Algeria	Kabyle	FAO (2012)
Morocco	Moroccan Beldi	Benabdeljelil and Arfaoui (2001)
Egypt	Fayoumi (very widespread breed), Dandarawi and Baladi Beheri	Hosny (2006); Osman et al. (2016)
Tunisia	Variable Breeds (important metissage)	Raach-Moujahed et al. (2011)
Southern Africa	Lebowa-Venda, Potchefstroom Koekoek, Boschveld, Ovambo and Naked Neck	Van Marle-Köster and Casey (2001); Mammo et al. (2008); Ajayi (2010); Tadelle and Fasil (2016); Mtileni et al. (2012); Idowu et al. (2018a)
Eastern Africa
Ethiopia	Characterization based on: *Plumage colour: Gebsima (greyish mixture), Key (red), Netch (white), Tikur (black), Anbesma, Seran, Libework, Netch Teterma, Tikur Teterma, Key Teterma, and Naked nack (Angete Melata); *The area of geographical origin or market shed name: Tilili, Horro, Chefe, Jarso, Netch, Tepi and Tikur.	Tadelle et al. (2003); FAO (2009); Assefa and Melesse (2018); Assefa and Melesse (2018)
Kenya	Variable. Major phenotypes include: normal feathered, naked-neck, frizzle-feathered, dwarf, crested-head, feathered shanks and rump-less	Magothe et al. (2012)
Tanzania	Kuchi and medium ecotype are commonly ecotype names used	Lyimo et al. (2013); Lwelamira et al. (2008)
Rwanda	Rwamagana, Rulindo, Ruhango, Muhanga and Kicukiro	Mahoro et al. (2017)
Burundi	Sekaganda and Imangubo or Injogori	Sebushahu (2008)
Sudan	The large Beladi, The bare neck, the home land of bare neck, The Betwil	Wani et al. (2014); Wimmers et al. (2000)
Western Africa
Nigeria	Fulani (spread over many African countries), Yoruba	Lasagna et al. (2020); Fayeye et al. (2005)
Burkina Faso	Some local breeds: Dori chicken, Peul (Fulani) chicken, dwarf chicken, curly chicken, naked neck chicken, Centre chicken and Konde chicken (big size) which are often grouped into two ecotypes: African chicken and Konde chicken	Yacouba et al. (2021)
Mali	Kokochiè, Wassa-ché (popular but resulting from crossbreeding)	Kuit et al. (1986); DNPIA (2015)
Niger	Kolonto	FAO (2009)
Central Africa
Cameroon	Dzaye, Dongwe, Zarwa and Brahman	Hako et al. (2015); Fotsa et al. (2011)
Chad	Djided Baladi, Karmout	Hassaballah et al. (2014) Hassaballah et al. (2015)

10. A model for improving indigenous chicken production in tropics

It is necessary to develop an appropriate production model for rural areas, which could contribute to the solution to the challenges of food and nutritional security in developing countries. This model is based on the preservation of an indigenous chicken gene pool that could have the following characteristics:

• – farmers well trained in the good practices of raising local chickens;

• – access to water: most indigenous chicken farmers live in vulnerable areas lacking adequate potable water for humans and livestock (Chikumba and Chimonyo 2014). This situation is worsened during the dry season when rainfall levels drop dramatically (Mwale and Masika 2009). However, access to water is essential for poultry;

• – a good quality and less expensive feed: a good, low-cost feed can be formulated using locally available resources composed of agri-food by-products such as corn and soybean bran, insect- worms and larva, and termites. Also, maggots are an important source of natural and rich animal protein for poultry, so they are a much more economical alternative containing 5% more protein than soybeans. Inclusion cannot exceed 10% (Adeniji 2007; Makinde 2015). The overall goal of production should ensure that the nutritional characteristic of the feed formulated should be done at a lower cost;

• – housing facilities: to limit non-disease-related mortality (predation). When wandering, chicks are often preyed upon by reptiles (snakes, monitor lizards, etc.), shrews and hawks (Moreda et al. 2013). One of the main limitations in indigenous chicken production is the attack of the predators, which cause considerable losses (Yemane et al. 2014; Sori et al. 2016);

• – health care: some vaccination: poultry diseases among indigenous chickens are dominated by Newcastle, Infectious bursa disease (or gumboro), Chronic respiratory disease and Fowl pox (FAO 2012; Odah et al. 2019);

• – about crossbreeding: the use of high performant exotic males is not a good strategy (Riise et al. 2005; Ayssiwede et al. 2013).

10.1. Training model to ensure food sovereignty

Training rural farmers is an important key to the sustainability of the production system. Trained farmers can adopt good husbandry practices to maximize productivity (Sajeev et al. 2012). The major concern in improving local chicken productivity is to ensure food security for the population located in most rural areas. Indeed, rural communities represent a large proportion of the African population, especially the most vulnerable society segment (Bekele 2020; Ogunkola et al. 2020). They own 80% of the chickens, mainly indigenous breeds (Gueye 1998). Implementing a sustainable model for improving local chicken production must emphasize training. Farmers must be taught good husbandry practices (Sajeev et al. 2012). Since women and children keep local chickens (Lamaro 2018), training must therefore be focused on women. Aspects such as farmer training groups, field demonstrations, farmer-to-farmer training and farmer clubs are among the elements to be included in the model (CropLife 2013). However, given the current challenges of lack of employment, young people must be encouraged to enter all agricultural trades. The agricultural models proposed to the young people in training must be related to the actual conditions of peasant life and especially its advantages. The improvement of the productivity of local breeds through lower-cost production strategies can attract the young to get involved and help reduce their mass exodus to the cities or outside of the country (Kaag et al. 2019). Thus, mobile training can be more helpful than audio and visual training lessons to save time and reach many young people (Dondeyne 2010). Sustainable rural farming must also address environmental concerns, such as managing dead chickens, especially during disease outbreaks. In this context, particular emphasis should be placed on biosecurity modules for local chickens. Training will inform farmers about different types of dietary resources which can substitute the conventional ingredients in poultry diets.

10.2. Use of locally available resources for feeding and herbal medicine in raising livestock

10.2.1. For feeding purpose

Feed accounts for about 70% of the total production cost of chicken (Ahiwe et al. 2018; Martínez et al. 2020). The great challenge for farmers is to formulate quality feed at a lower cost. Also, energy and protein sources represent a large proportion of feed ingredients (Van der Klis et al. 2010). Thus, the concern will be for farmers to find locally available feed sources to substitute energy and protein sources (Mwesigwa et al. 2015). In this sense, in rural areas, without knowing it, farmers are finding alternatives to substitute maize and soybean. However, the substitution is poorly done due to a lack of information on their nutritive value. Regular training for farmers is suggested (Devi and Diarra 2019). Several locally available feed ingredients can be included in the poultry diet (FAO 2012; Diarra and Anand 2020) as a source of energy or protein:

• – Energy sources: the dietary recommendations vary from 100 to 270 g/kg diet (Dayal et al. 2018; Ndelekwute et al. 2020), 100 g/kg diet (Diarra 2016) and up to 50% in diet (Ravindran 2010), respectively for cassava peel meal, giant taro root meal and sweet potato tuber. Inclusions levels for citrus peel meal, sun-dried banana peel, sun-dried papaya peel meal and mango kernel seed meal range from 50–150 g/kg diet (Oluremi et al. 2006; Nazok et al. 2010; Behera et al. 2019), 0.5% in the diet (Chueh et al. 2019), 90–120 g/kg diet (Kamaruzzaman et al. 2005) and 50–100 g/kg diet (Odunsi 2005; Diarra 2014; Orayaga et al. 2017) respectively. Also, brewers’ spent grain is recommended to be included at 100–400 g/kg (Denstadli et al. 2010; Gebremedhn et al. 2019);

• – Protein sources: inclusion levels range from 200–300 g/kg (Diarra et al. 2015; Devi and Diarra 2017; Haetinger et al. 2021) and 160–350 g/kg diet (Martínez et al. 2020; Abdollahi et al. 2016; Sundu et al. 2006; Diarra et al. 2018) respectively copra cake and palm kernel cake. It is possible to include cassava and sweet potato leaf meals at 50–200 g/kg (Ngueda Djeuta et al. 2020; Ngueda Djeuta et al. 2022; Bakare et al. 2020; Devi and Diarra 2019; Morgan and Choct 2016; Khan 2017; Beckford and Bartlett 2015; Mmereole 2009).

10.2.2. For ethnoveterinary treatment purpose

Local African chickens are able to survive persistent exposure to pathogens. However, in rural areas, the low biosecurity measures and high risk of infectious diseases, lack of proper treatments (vaccines and drugs) and the attack of the predators (Conan et al. 2012; Mpenda et al. 2019) lead to high mortality. Newcastle, Gumboro, coccidiosis and respiratory infections and Fowl pox are known to cause more mortality in various parts of Africa (Mushi et al. 2006; Mpenda et al. 2019; Odah et al. 2019; Simbizi et al. 2021). There is a vast local knowledge for indigenous chicken health management. The use of this endogenous knowledge can reduce the costs of conventional treatments. Nevertheless, the production model for rural areas suggests vaccinating chickens and using traditional treatments for infectious and parasitic diseases. Traditional treatments (natural remedies) involve resources (plant parts) which are found in abundance in each community (Syakalima et al. 2017). Also, farmers are able to describe diseases. They have endogenous knowledge to treat them (that should not be neglected) and pass on this knowledge to generations. The role of science would be to help them define the appropriate posology in herbal medicine in treatments for curing diseases without harming the chickens’ physiological organs. For example, for treatment of internal parasites and digestive infections, Cassia Abbreviata/Singueana, Trema Orientalis, Julbernardia globiflora, Terminalia sericea and Brachystegia longifolia is often used (Syakalima et al. 2017). Combretum mole and Pepper (Pilipili) (Capsicum sp.) are said to treat chronic respiratory diseases and intestinal worms while Croton megalocarpus are used for Coryza (Okitoi et al. 2007). The use of certain plants such as Aloes vera appears in the treatment of different types of diseases (viral, infectious) (Sujatha et al. 2017).

11. Reproductive performance traits of indigenous chicken in some African countries and challenge encountered

Indigenous chicken breeds in some African countries exhibit low body weight, late maturity, poor egg production, low egg weight and high mortality (Gueye 1998; Halima et al. 2007; Habte et al. 2013). Reproductive performance traits are crucial for chicken production (Mersha and Senbeta 2020) which include age at sexual maturity. It expresses the achievement of the full development of the reproductive system which determines fertility features and influences reproductive performance (Forment et al. 2009). According to the reproductive performance of local hen breeds in some African countries, body weights of hens vary almost from 1050 to 1400 g, 1500 to 1700 g, 870–1600 g, 770–1500 g and 700–1260 g, respectively for Northern Africa, Southern Africa, Eastern Africa and Western Africa (Tables 2–6). Some countries are distinguished by light breeds: Egypt, Tanzania, Senegal, Chad and the Democratic Republic of Congo (Tables 2–6). The delayed maturity of the hens results in high age at the first egg presented in Tables 2–6. The age at the first egg varies from 129 days (South Africa with naked neck breed) to 280 days (East Africa, particularly Tanzania). Overall, the number of eggs laid per year and average egg weight is lower compared to exotic breeds. Getu et al. (2014) recorded higher number of eggs and egg weight with Rhode Island Red and White Leghorn reared under scavenging environments in Northern Ethiopia. According to Tables 2–6, the number of eggs laid per year is lower for the Eastern, Western and Central African country breeds compared to Northern and Southern African countries. Moreover, South African local breeds present the highest egg weight among all the local African breeds. This can be explained by the genetic potential that is the result of years of selection (Mujyambere et al. 2022). Based on the observation of acceptable hatching rates (Ndofor et al. 2014; Idowu et al. 2018b; Mujyambere et al. 2022), the poor productive performance of indigenous chickens could be associated to high chick mortality, particularly before the weaning period (Mengesha et al. 2022). Feed shortage, accidents, diseases, and predators limit chicken productivity in the rural areas (Krishna et al. 2012; Mahoro et al. 2017). According to Table 7, chicken breeds of South Africa show the lowest mortality (4.5%). Management practices, outbreak diseases such as Newcastle Disease and affection of internal and external parasites are reported to exacerbate the reduction of flock size in many African countries. In the same vein, Krishna et al. (2012) added the other important factors, such as predators and accidents. The lack of information pointed out by Tadelle et al. (2003) is an important factor to include among the factors that contribute to the decrease in the size of the livestock population of farmers. In fact, concerning responsibilities in the management of poultry flocks, women play the first role due to their low literacy (Muchadeyi et al. 2004). For this purpose, training sessions in local languages focussing on women are highly recommended leading to the improvement of the management practices.

Table 2. Reproductive performance of local female in some Northern African countries.

African countries	Performances	Reference
Algeria	*BW at 1st egg: 1334.05 g; *age at 1st egg: 165.96 d; *eggs laid per year: 173.44; *egg weight: 43.70–53.37 g 35–36 wk: 43.70 g; 50–51 wk: 49.54 g.	Moula et al. (2009); Moula et al. (2013)
Morocco	*Age at 1st egg: 174 d; *eggs laid per year: 78; *BW at 1st egg: 1200–1400 g. *egg weight: 40–44 g	Raach-Moujahed et al. (2011); Benabdeljelil and Arfaoui (2001)
Egypt	*Age at 1st egg: 139 d; *eggs laid per year: 141 (Fayoumi), 128 (Dandarawi); *BW at 1st egg: 1050 g; *egg weight: 32 g.	Raach-Moujahed et al. (2011)
Tunisia	*BW at: 32/73 wk for feather type: clear brown: 1340 g/1730; dark brown: 1374 g/1678 g; black: 1230 g/1470 g; white: 1251 g/1416 g; *BW at 18 wk: 1206 g; *eggs laid per year: 127.	Bessadok et al. (2003)

BW: Body weight, age expressed in d (day).

Table 3. Reproductive performance of local female in South Africa.

Country	Performances	Reference
Southern Africa	Potchefstroom Koekoek *Average eggs laid per year: 198 *BW: 16 wk: 1400 g and 20 wk: 1700g *Age at 1st egg: 130 d *Egg weight: 55.7 g Naked Neck *Average eggs laid per year: 138.9 *BW: 16 wk: 1100 g and 20 wk: 1400 g *Age at 1st egg: 129 d *Egg weight: 55.5 g Lebowa-Venda *Average eggs laid per year: 129 *BW: 16 wk: 1240 g and 20 wk: 1400 g *Age at 1st egg: 143 d *Egg weight: 52.5 g Ovambo *Average eggs laid per year: 129 *BW: 16 wk: 1320 g and 20 wk: 1540 g *Age at 1st egg: 143 d *Egg weight: 52.5 g	Van Marle-Köster and Casey (2001); Glenneis (2020); Mammo et al. (2008); Ajayi (2010); Grobbelaar et al. (2010); Tadelle and Fasil (2016)

BW: Body weight, age expressed in d (day).

Table 4. Reproductive performance of local female in some Eastern African countries.

African countries	Performances	Reference
Ethiopia	*Average eggs laid per year: 30–60 and ranged from 18–57 in North-West Ethiopia; *BW at 1st egg: 914−1300 g *Age at 1st egg: 177–182 d *Egg weight: 38−39.4 g	Aleme (2022); Tolasa (2021); Tadelle et al. (2003); ; Kassa et al. (2021); Yemane et al. (2014); Moges et al. (2010)
Kenya	*Average eggs laid per year: 30–75 with average of 40; *BW at 1st egg: 1320 g *Age at 1st egg: 224 d *Egg weight: range from 36 g to 52 g with average of 42.7 g.	Magothe et al. (2012); Juma and Ondwasy (2002); Ndegwa and Kimani (1996); Kingori et al. (2010)
Tanzania	*Average eggs laid per year: 20−50; *BW at 1st egg: 20 wk: Kuchi ecotype: Kuchi ecotype 870−1567 g and medium ecotype: 817−1419 g. *Age at 1st egg: 168–280 d *Egg weight: 32-57 g	Guni et al. (2013); Mwalusanya et al. (2002); Kusina and Kusina (1999) cited by Muchadeyi et al. (2007); Lwelamira et al. (2008)
Rwanda	*Average eggs laid per year: 30−60; *BW at 1st egg: 1400 g *Age at 1st egg: 174.4−197.4 d *Egg weight: 33.2−47.9 g	Mbuza et al. (2016); Mahoro et al. (2017); Hirwa et al. (2019)
Uganda	*Average eggs laid per year: 20–50 *BW at 1st egg: 1300 g–1600 g *Age at 1st egg: 172.2−212.8 d *Egg weight: 40−50 g	Nakkazi et al. (2014); Kyarishma et al. (2004); Ssewannyana et al. (2008); Kugonza et al. (2008)

BW: Body weight, age expressed in d (day).

Table 5. Reproductive performance of local female in some Western African countries.

African countries	Performances	Reference
Nigeria	*Average eggs laid per year: 20–112 *BW at 1st egg: 940–1208 g *Age at 1st egg: 145–169 d *Egg weight: 32–42 g with average mean of 36.8 g	Adetayo and Babafunso (2001); Akinokun (1990); Nwosu and Omeje (1985); Ndofor et al. (2014)
Mali	*Average eggs laid per year: 35 *BW at 1st egg: 1170 g *Age at 1st egg: 168 d *Egg weight: 34.4 g	Kassambara (1989)
Senegal	*Average eggs laid per year: 36–50 *BW at 1st egg: 770–1280 g *Age at 1st egg: 175 d *Egg weight: 37.5–40 g	Missohou et al. (2002); Buldgen et al. (1992); Ayssiwede et al. (2013)
Burkina Faso	*Average eggs laid per year: 36–50 *BW at maturity: 956.77–1498.89 g *Age at 1st egg: 154–182 d *Egg weight: 30–40 g	Yacouba et al. (2021); Gueye (1998), Guèye (2000); Farrell et al. (1999); Paterson et al. (2000)

BW: Body weight, age expressed in d (day).

Table 6. Reproductive performance of local female in some Central African countries.

African countries	Performances	Reference
Cameroon	*BW at 1st egg: 1160–1259 g *Age at 1st egg: 140 d *Egg weight: 43–44g *Average eggs laid per year: 49.3–54	Fotsa (2008)
Chad	*Average eggs laid per year: 31.5–41 *BW at 1st egg: 700–1050 g *Age at 1st egg: 156–178 d *Egg weight: 30.74 g	Mopate (2010); Hassaballah et al. (2015); Youssouf et al. (2014)
RDC	*Average eggs laid per year: 12–45 *BW at maturity: 5 wk: 750 g *Age at 1st egg: 147–252 d *Egg weight: 41.91 g	Mugumaarhahama et al. (2016); Moula et al. (2012); Fulbert et al. (2010)

BW: Body weight, age expressed in d (day).

Table 7. Average mortality rate recorded and challenges facing local chicken farming in some African countries.

Country	Average mortality rate	Causes or challenges	References
Northern Africa
Tunisia	16 wk: 9.37%	Management practices	Moujahed and Haddad (2013)
Algeria	0–19 wk: 13.04% 19–72 wk: 51%	Cause: has been correlated to cage rearing in-station study	Moula et al. (2013)
Morocco	Young chicken: 46%–76% Mature chicken: 38%–77%	New Castle disease particularly in Winter cold weather	Benabdeljelil and Arfaoui (2001)
Egypt	24 wk: 4.30%	Management practices	Abdel-Aziz et al. (2013)
Southern Africa
South Africa	Average mean:4.5% (highest for Koekoek breed)	Management practices and outbreak diseases	Idowu et al. (2018a)
Ethiopia	26 wk: 22.6%	Performance can be increased by half with the provision of improved feeding, housing, and health care	Halima et al. (2007); Moges et al. (2010); Tolasa (2021)
Kenya	Variable	Diseases mostly Newcastle Disease and internal and external parasites	Mwamachi et al. (2000); Okitoi (2000); ; Mungube et al. (2008)
Uganda	11 wk: 25–32.3%	Diseases mostly Newcastle Disease	Ssewannyana et al. (2008); Kugonza et al. (2008)
Westhern Africa
Senegal	12 wk: 43%–59%	Outbreak Diseases mostly Newcastle Disease and predators	Missohou et al. (2002); Nahimana et al. (2016)
Some west african countries	8%–10%	Outbreak Diseases mostly Newcastle Disease, internal and external parasites and predators	Gueye (1998); Guèye (2002); ; Sonaiya (2007)
Middle Africa
Cameroon	44.12%	Outbreak Diseases	Fotsa (2008)
Democratic Republic of Congo	58%–68%	Outbreak Diseases	Fulbert et al. (2010)

12. Conclusion

Poultry production is currently confronted with the issue of climate change, which is a global concern. In this context, preservation of the available chicken ecotypes already adapted to the agro-ecological conditions of the different production areas is needed. As these ecotypes are already accustomed to extreme weather conditions in the world’s tropical regions, changing feeding, housing and veterinary care practices are the best way to improve the productivity of these indigenous strains. Also, local chicken is considered as historical and cultural patrimony of a country and should be preserved. A genetic approach to improving productivity by crossbreeding with exotic strains (developed in temperate and less adapted to tropical areas) is not the appropriate model. Even if it should be done, it is highly recommended to be done in a controlled way to avoid the extinction of local strains. In this situation, any genetic improvement of local strains must be preceded by the identification, phenotypic characterization, and performance assessment of the available local strains. This literature review clearly shows the difficulty of accessing scientific data on the performance of local chickens. Most of the data were based on surveys, which poses a problem of accuracy of the recorded values. Moreover, a sustainable use of crossbreeding approach should include a plan for the conservation of the native genetic pool on which it is founded to avoid any risk of extinction. These strategies, coupled with the improvement of production factors such as feed, habitat and veterinary care, will allow chickens to exploit their full genetic potential. More studies are needed to update the knowledge gap on the characterization and performance of the birds.

Animal welfare statement

The authors confirm that the ethical standards of the journal, as noted on the journal’s author guidelines page, have been adhered to. The manuscript does not contain clinical studies or patient data. Thus, as this is a review article with no original research data, no ethical approval was required.

Disclosure statement

No potential conflict of interest was reported by the author(s).