J. of Agricultural Chemistry and Biotechnology, Mansoura Univ., Vol. 16 (7):109 - 116, 2025 Journal of Agricultural Chemistry and Biotechnology Journal homepage & Available online at: www.jacb.journals.ekb.eg * Corresponding author. E-mail address: abdelmeged797@gmail.com DOI: 10.21608/jacb.2025.401611.1118 Morphological description and C-banding karyotype of Baladi Pigeon (Columba livia) occurring in Egypt Abdallah, A. A. *; S. A. M. Osman ; Gehan M. Anwar and A. M. Ata Dept. Genet., Fac. Agric., Minia Univ., Minia, Egypt Cross Mark Article Information Received 10 /7 /2025 Accpted 16 / 7/2025 ABSTRACT The current work provides a detailed morphological and cytogenetic study of the Egyptian Baladi pigeon (Columba livia) collected from three localities (Maghagha, Samalout, Mallawy) of Minia, (Egypt) to describe its morphometric profiling and karyotype through conventional staining and C-banding techniques. Results showed that, Pigeon birds were morphologically diverse and exhibited variations in 15 studied traits particularly those of body size, head, beak size, and appendage length. Likewise, karyotype analysis showed a diploid number (2n=80) that made up of 9 macro-chromosome pairs (8 pairs of autosomes and ZW sex chromosomes) and 62 micro- chromosomes. Results also showed that the macrochromosomes no.1 was the largest one in the karyotype and it is metacentric, while chromosome no.2 is large meta- or submetacentric. Chromosome no.3 is large sub- telocentric. Chromosome nos.4 and 5 were medium sub-metacentrics, while chromosome nos.6, 7 and 8 are small telocentric. Z chromosome was medium sized submetacentric, while W was small submetacentric. The karyotype formula is 1m + 5sm + 1st + 3t or 2m + 2sm + 1st + 3t. Birds collected from the three localities likely possessed similar karyotypic parameters. For instance, the total haploid lengths of the chromosome set are 63.68, 35.21and 36.94. C-band variations are clearly found among 8 investigated macro-chromosomes. For instance, chromosomes 1, 2, 3, 4, and 6 mostly have large dark heterochromatin. It could be noted that twenty to thirty of the micro-chromosomes have clear c-banding blocks that were seen in almost all examined cells. Morphometric and cytogenetic significance of these results is discussed. Keywords: Pigeon – morphology –cytogenetic - karyotype – C-banding INTRODUCTION The pigeon (Columba livia) which inhabits our backyards is considered as a member of the wild pigeon (Blasco et al., 2014). The feral pigeon was probably domesticated in the Middle East and Mediterranean basins at least 5,000 years ago (Domyan and Shapiro 2017). It is belonging to the Kingdom: Animalia, Phylum: Chordata, Class: Aves, Order: Columbiformes, Family: Columbidae, Genus: Columba, and species is Columba livia, a feral ancestor of the domesticated pigeon. The pigeon is occurred everywhere due to simple domestication (Johnston and Janiga, 1995). This may grant it the honor of being the earliest winged bird to be domesticated and, perhaps, had its phenotypic variation most changeable (Price, 2002). Pigeons have filled some of man's needs (food source, communication tool, racing pigeon) for centuries. Wild-type pigeons possess blue-grey feathers with black wing bars. Selective breeding of domestic pigeons has introduced a wide range of plumage colors and patterns due to genetic reasons such as those regulated by the melanin-producing genes and sex-linked loci (Shapiro et al., 2013). Wild-type ash-red, brown, and blue represent the primary colorations. These traits are due to genetic reasons, and ash-red is a dominant one (Shapiro et al., 2013). Foot feathering in pigeon has been associated with the regulation of the PITX1 and Tbx5 genes, resulting in feathered hind feet and leg bone morphological changes (Domyan and Shapiro 2016). Morphogenesis is a most valuable tool in developmental investigation of birds. Pigeons make an excellent model for morphological variation studies. For instance, wild rock pigeon ancestors were taken and as with all domesticates, selectively bred for numerous morphological and behavioral characteristics. Particularly, those of beak and head shape that have been intensely selected and resulted in pigeon breeds at the outskirts of distribution of width, length, depth, and curvature (Helms and Brugmann, 2022 and Çelik, 2022). The karyotypes of an organism are normally arranged in order of their decreasing size, and they are highly informative regarding the organization and the genetic composition of an organism (Ata et al, 2007 and 2012). The domestic pigeon possesses a karyotype of 40 chromosome pairs, which are composed of 9 macro-chromosomes and 31 micro-chromosome pairs (Shibusawa et al., 2001). One of the most distinct features of the domestic pigeon karyotype is the very large number of micro-chromosomes, which are much smaller than the macro-chromosomes. Micro-chromosomes were recently discovered to be of very significant importance in the genomic evolution and diversity of birds because they contain a high number of genes and are involved in very important biological processes such as sex determination (Ata et al, 2017 and 2021). For pigeons, micro-chromosomes have been thought to have evolved from their ancestral birds and have undergone some evolutionary adaptations to suit their current genomic organization (Burt, 2002). These gene-rich, highly conserved micro-chromosomes were seemingly present in the common ancestor of reptiles and modern birds, suggesting their ancient evolutionary origin (Osman et al., 2006 and Uno et al., 2012). Micro-chromosomal