Growth and reproductive performance traits are traits of economic importance for sheep selection and productivity improvement interventions. This study aimed at comparative evaluation 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 linear 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 significantly (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 reproduction 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.

In Ethiopia,there are 32.85 millions of sheep,more than 99 % of which are indigenous.However,the productivity of local sheep under traditional production system is low with high mortality of sheep.There are two ways of improving performance of sheep and goats,namely improving the enviroment of animals and/or improving there genetic potential.The aim of this study was to predict genetic gains of breedingobjective traits and select the best sheep selection scheme for Gumuz andWashera sheep. Body size(six month weight and yearling weight) and litter size were breeding objective traits identified by own flock animal ranking experiment and personal interview. Deterministic approach of ZPLAN computor program is used for modeling input parametres of Gumuz and Washera sheep and simulating breeding plans using gene flow method and selection index procedures. One-tier cooperative sheep breeding scheme were proposed whereby ram exchange between and within villages is the main means of genetic dissimination. Genetic gains predicted for six month weight of Gumuz and Washera sheep were 0.43 and 0.55 kg,respectively. Genetic gains predicted for yearling weight of Gumuz and Washera sheep were 0.55 and 0.60 kg,respectively. Genetic gains predicted for litter  size of Gumuz and Washera sheep were 0.08 and 0.09 lambs,respectively. The lower rate of inbreeding, the higher monetary genetic gain for aggregate genotype,higher return to investmnet and higher profit/ewe/year were quality measures of breeding program considered to prefer scheme 4 for both Gumuz and Washera sheep.Hence,for both Gumuz and Washera sheep populations a sheep selection scheme designed with 15 % selection proportion and one year ram use for breeding was recommended. Special emphasis need to be given to yearling weight with higher predicted genetic response and higher percentage return to investment.

Growth and reproductive performance traits are traits of economic importance for sheep selection and productivity improvement. This study aimed at comparative evaluation of growth and reproductive performance traits of Washera and Gumuz indigenous sheep in the highland and lowland agro-ecologies of northwestern Ethiopia. Data on growth performance traits were collected from 412 Washera (162 male and 250 female) lambs and 208 Gumuz (72 male and 136 female) lambs. Concurrently, data on reproductive performance traits were collected from 406 Washera (130 rams and 276 ewes) sheep and 213 Gumuz (75 rams and 138 ewes) sheep. General linear model (GLM) univariate procedure was employed to analyze the collected data. Mean±SD values of adjusted yearling weight of Washera and Gumuz sheep was 21.80±1.91 and 20.37±1.85 kg, respectively. Breed type affect live weight significantly (P<0.001). Mean±SD values of age at first lambing, lambing interval and annual reproductive rate of Washera sheep were 11.69±1.96 months, 9.27±3.53 months and 2.12 lambs, respectively. The corresponding values for Gumuz sheep were 12.51±1.95 months, 10.43±1.25 months and 1.71 lambs, respectively. Production and reproduction performance values for traits of Washera and Gumuz sheep were comparable to other Ethiopian and African breeds. These values can be used to set up breeding objectives for optimizing breeding schemes of sheep breeding program. In addition, the varied minimum and maximum values of growth and reproductive performance traits indicates that there is within breed variability. This variation could be used as a basis for within breed selection among indigenous sheep by giving special consideration to growth rate traits, believed to have medium heritability values.

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