Philippine Journal of Science
150 (3): 837-846, June 2021
ISSN 0031 – 7683
Date Received: 05 Oct 2020

Genetic Diversity of Philippine Carabao (Bubalus bubalis)
Using Mitochondrial DNA D-loop Variation: Implications
to Conservation and Management

Lilian P. Villamor^1,2*, Yukimizu Takahashi²,
Koh Nomura², and Takashi Amano³

¹Department of Agriculture, Philippine Carabao Center National Headquarters
and Gene Pool Science City of Muñoz, Nueva Ecija 3120 Philippines
²Tokyo University of Agriculture, Atsugi, Kanagawa 243-0034 Japan
³Yamazaki University of Animal Health Technology, Hachioji, Tokyo 192-0364 Japan

*Corresponding author: lpv.2012@gmail.com

ABSTRACT

Developing rational conservation programs for Philippine carabao (PC) (Bubalus bubalis) requires knowledge on the pattern of genetic variability within and between populations of swamp buffalo. Studying the genetic diversity and phylogeographic structure is essential to understand the distribution of the Philippine swamp buffalo maternal haplotypes towards the PC conservation. This study aimed to determine the genetic diversity and the phylogeographic structure of PC using molecular approaches. D-loop of the mitochondrial DNA (mtDNA) on the PC B. bubalis (n = 107) were randomly selected from 23 populations across the islands of Luzon, Visayas, and Mindanao as major islands sub-groups. DNA was isolated from the whole blood, and the D-loop region of the swamp buffalo was amplified using the polymerase chain reaction (PCR). Purified PCR products were sequenced with the Applied Biosystems Automated 3730. Results showed that the phylogenetic analyses detected 16 mtDNA haplotypes observed with 12 variable sites and haplotype and nucleotide diversities of 0.695 ± 0.042 and 0.004 ± 0.001, respectively. This study also identified the delineation of swamp buffalo populations into major and minor groups. Among the major groups, 14 haplotypes were included, and sequences were incorporated in the maternal lineage A. Minor groups which fell in the maternal lineage B identified two new haplotypes. Thus, the current findings revealed the moderate mtDNA haplotype diversity and weak phylogeographic structure of the PC. In addition, the results of this study will serve as a vital starting point in planning effective strategies and prioritizing the genetic resources for PC conservation and management programs.