Advances in the genetic characterization of guinea fowl in Africa: a comprehensive overview of the current status, progress of genome genotyping, and future perspectives

Abstract

Guinea fowls are one of the indigenous species of Africa and constitute an alternative source of high-quality meat and eggs. Several studies have been conducted on guinea fowl management, reproduction, and genetic characterization. Guinea fowl are predominantly reared under extensive or semi-intensive systems, where they cohabit with other poultry species and roam freely during the day. These systems, characterized by small flock sizes and suboptimal housing conditions, contribute to reduced productivity and high mortality rates. The zootechnical performances of guinea fowl under these systems is often low due to difficult breeding conditions and climatic variability. This review aims to provide a comprehensive synthesis of current knowledge on the genetic characterization of guinea fowl in Africa, and to examine its implications for sustainable guinea fowl production and conservation. Relevant literature on the genetic characterization of guinea fowl in Africa was gathered through systematic searches in databases, focusing on studies conducted between 2000 and 2024. Molecular characterization methods used include microsatellite markers and mitochondrial DNA analysis. The sex-ratio is typically three females per male, with laying beginning between 7 and 9 months, and egg laying mostly occurs during the rainy season when food is abundant. Growth performance varies according to sex, farming system, disease control, and strain. Phenotypic traits of guinea fowl include plumage colours, wattle, and eye colour variations, which are influenced by genetic and environmental factors. For instance, studies in different regions have reported varying prevalence of plumage colours, with pearl grey being the most common in many areas, and white or mostly pied colours in others. Colour variations play a role in the thermoregulation and adaptation to local climates. Biometric characteristics such as body weight, chest circumference, body length, thigh length, shank length, and wingspan are crucial for assessing growth and market value. Strong correlations exist between body weight and measurements of shank and thigh length, thereby aiding in the predictive assessment of growth performance. Molecular characterization using microsatellite markers revealed high phenotypic diversity among guinea fowl populations but low differentiation between local breeds, likely due to the free-range management system and gene flow across regions. Studies using mitochondrial DNA markers have also revealed extensive genetic intermixing, suggesting recent domestication and the lack of distinct maternal genetic structures. These genetic insights are important for developing guinea fowl breeding programs that enhance productivity and adaptation to tropical conditions. The genetic characterization of guinea fowl has strong implications for the African poultry industry, as it supports the development of resilient and productive breeds suited to local conditions, while also contributing to the conservation of indigenous genetic resources critical for long-term food security and rural development.

Keywords

• Africa
• Farm animal biodiversity
• Guinea fowl
• Molecular genetic characterization
• Phenotypic characterization