Phenotypic diversity and phylogenetic relationship between the Bakosi/Baweri and other pig breeds (Sus scrofa Domesticus) in the humid forest with monomodal rainfall agro-ecological zone of Cameroon

Abstract

The present study was conducted from April to May 2017 in the humid forest with monomodal rainfall (agro-ecological) zone of Cameroon with the following geographical coordinates: 44˚10’00’’- 5˚50’00’’LN and 9˚10’00’’- 9˚30’00’’LE. The objective was to describe and determine the morphology, biometric characteristics, prediction equation of live weight and the genetic variability of this pig population of the humid forest with monomodal rainfall agro-ecological zone of Cameroon. For this purpose, a data collection scope of 19 traits (quantitative and qualitative) was conducted on a total of 208 pigs including males and females from two divisions and six sub-divisions of the South West Region of Cameroon. The main results show that the black coat colour (44.7%) is dominant with majority of pigs having black (51.06%) skin pigmentation. Moreover, majority of pigs are rectilinear (48.6%) with large (53.4%) erect (48.1%) ears which are mostly oriented forwards (39.9). The pigs are mostly docile (53.8%) and have curly tails (55.3%). The main body measurements (in cm) gave the following values: body length (87.28±2.18), heart girth (79.59±1.89), height at withers (58.36±1.22), eye distance (16.85±0.30), ear length (21.48±0.55), head length (30.00±6.59), snoot length (13.60±0.30), hock circumference (20.36±0.47), tail length (27.37±0.63) and the average live weight (in kg 61.56±5.03). The hearth girth best predict the live weight of pigs in the humid forest with monomodal rainfall agro-ecological zone of Cameroon. The polynomial equations with highest coefficients (LW= 0.039HG2 - 6.259HG +305.7 R2=0.930, LW= 0.028HG2 - 3.498HG+ 132 R2=0.899) best predict the live weight of the exotic and crossbreeds respectively while the power equation with the highest coefficient (LW= 3E-06HG3.782 R2=0.229) best predict that of Bakosi/Bakweri breeds. The principal component analysis (PCA) revealed that the first three components explain 77.34% of the genetic variability in the studied population. The discriminant analysis (DA) suggested that the population is made of three genetic types (I, II and III) with genetic type III having the highest characteristics. The dendrogram showed that type I and II are closest and type II and III are genetically more distant. In conclusion, the genetic variability obtained within the population offers possibilities for their genetic improvement by convention methods of selection and crossing.

Keywords: biodiversity, biometric characteristics, Cameroon, pig