On-farm evaluation of growth and reproductive performances of Washera and Gumuz sheep in northwestern Ethiopia: Basics for setting up breeding objectives/ goals
Abstract
Growth and reproductive performance traits are traits of economic importance for sheep
selection and productivity improvement interventions. This study aimed at comparative eval uation of growth and reproductive performance traits of sheep in the highland and lowland
agro-ecologies of northwestern Ethiopia. Data on growth performance traits were collected
from 144 Washera (78 males and 66 females) lambs and 72 Gumuz (37 males and 35
females) lambs. Data on reproductive performance traits were collected from 260 Washera
(130 rams and 130 ewes) sheep and 150 Gumuz (75 rams and 75 ewes) sheep. General lin ear model univariate procedure was employed to analyze the collected data. Breed, the
interaction effect between breed and season of birth as well as the interaction effect
between breed and type of birth all exerted very high significant effect (P<0.001) on live
weight at all age groups. Breed type affected pre-weaning average daily weight gain signifi cantly (P<0.01). Pre-weaning average daily weight gain of Washera (70 g/day) was found
much better performance than 60 g/day of Gumuz. Breed type exerts significant (P<0.05)
effect on age at first lambing, lambing interval, annual reproductive rate and number of
lambs born per ewe life time. Average age at first lambing and lambing interval of Washera
sheep were 11.69 months and 9.27 months, respectively. The corresponding values for
Gumuz sheep were 12.51 months and 10.43 months, respectively. Production and repro duction performance values of traits varied across the two breeds and sexes as well. These
values can be used to set up breeding objectives or goals for selective breeding of sheep
giving special emphasis to growth traits believed to have medium heritability values