CLUSTER ANALYSIS OF YEARLING BODY WEIGHT OF SHEEP OF NORTHERN NIGERIA AND THEIR CROSSES

Abstract

Clumping structure of yearling body weight among sheep of Northern Nigeria and their crosses was investigated using cluster analysis. Body weights of 65 yearling sheep were also analyzed using General Linear Model procedure of SAS. Distances were used to construct dendrogram using the Unweighted Pairs Group Method Analysis implemented in R 2.13.0 package. TREE procedure that prints the dendrogram based on the distances between the clusters was introduced in PROC CLUSTER procedure. Yearling genotype affected BWT_12 (P<0.05). The pure Balami yearling (BL X BL) had the highest body weight at 12 months (29.10±4.02 kg). Yearling produced from Balami- sired mating with Yankasa ewe had the next heaviest weight (24.00±2.84 kg). This was followed in the third ranking when Balami was as the dam and Uda was used as the sire (20.50±4.02 kg). The least overall weight at 12 months of age was recorded when Yankasa was used as the sire on Balami ewe (15.12±4.02 kg). The BWT_12 recorded for YK x YK (14.79±0.80 kg) was similar (P>0.05) to what was obtained when Yankasa was used as sire on Balami ewe. Sheep of Northern Nigeria and their crosses were grouped into two clusters at distance 2.656 on the basis of body weight of the yearling sheep. Pure Balami (BL X BL) formed the first cluster while the rest of the genotypes belong to the second cluster. The yearling body weight of Balami was superior to that of other genotypes. The cluster analysis grouped pure Balami yearling distinctly from other genotypes. Improvement programmes of Nigerian sheep breeds should consider exploitation of the genetic potentials of Balami rams and ewes in terms of fast growth rate.