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dc.contributor.advisor Prof. Harpal Singh, Prof. Fekadu Regassa
dc.contributor.advisor Dr. Alemayehu Lemma, Dr. Tefera Yilma
dc.contributor.author Theodros, Tekle
dc.date.accessioned 2018-11-29T08:32:55Z
dc.date.available 2018-11-29T08:32:55Z
dc.date.issued 2017-07
dc.identifier.uri http://localhost:80/xmlui/handle/123456789/14674
dc.description PhD Thesis en_US
dc.description.abstract Studies were undertaken from December 2014 to June 2015, aimed at assessing the management practice and constraints of Afar and Central-Highlands goats (CHG); the reproductive traits and meat production potential of bucks of Abergelle, Afar and CHG which originated from traditional systems in north Ethiopia. In the cross sectional survey, pastoral system of Yallo district (Afar) and mixed crop-livestock system of Raya Azebo district (Tigray) were visited in order to assess the management practice and constraints of goat production. Studies on scrotal and testicular traits, linear body measurements (LBMs) and meat production potential were undertaken at Abergelle slaughterhouse, through recording of breed, age, body condition score, body weight (BW), scrotal circumference (SC) and LBMs as well as teticular traits, quality attributes of sperm recovered from tail of epididymis and hot carcass weight (HCW) taken after slaughter. In addition, dressing percentage (DP) was computed using BW and HCW. Descriptive statistics, chi square, rank analysis, analysis of variance and regression analysis were the statistical tools used to analyze the data. The survey showed goats to be highly preferred species kept for milk production and as source of income in Yallo and Raya Azebo districts, respectively. Goats were provided with differing type of shelter across the systems. In both systems, the traditional goat rearing practice was mainly based on naturally available feed resources with feed scarcity very common in the mixed farming system of Raya Azebo. Buck ownership varied with production system, in both systems mating was partially controlled through selection of breeding males. Milk production potential of the dam in Yallo and body size in Raya Azebo district were important buck selection criteria. Both production systems were faced with more or less similar constraints. A wider scrotal and testicular circumference as well as testicular and epididymal weights were recorded in bucks of CHG. Subsequently, CHG had a relatively good sperm quality in terms of motility, percent live, concentration with fewer morphological defects. The correlation between BW, SC and testicular traits was not uniform across the study bucks. Compared to BW, SC had better correlation with post-mortem testicular traits. Age had significant effect on LBMs (heart girth, height at withers, body length and pelvic width), BW, HCW and DP. Though bucks of CHG and Abergelle breed had comparable HCW, most of the LBMs and BW were higher in bucks of CHG. Dressing percentage of 44.8 %; 43.8 % and 43.7 % were recorded in Abergelle, Afar and CHG bucks, respectively. Models set for predicting HCW of bucks of Abergelle and CHG at age of 2 PPI and Afar bucks at age category of 0 PPI and 1 PPI were best explaining the variation in HCW compared with models set for predicting HCW of bucks of other age categories of their respective breed. Models set for predicting DP of bucks of Abergelle at age category of 1PPI; Afar at age category of 0 PPI and 2 PPI and CHG at age category of 0 PPI were best explaining the variation in DP compared with models set for predicting DP of bucks of other age categories of their respective breed. In order to improve performance of indeginous goat breeds, data on the management practice and the constraints, current reproductive and productive potential of goat breeds is required. The models set for predicting HCW and DP of the study bucks would be useful for selecting bucks for better meat production. Similar studies involving bucks at older age and all the indeginous goat breeds in Ethiopia are required. en_US
dc.language.iso en en_US
dc.subject body and carcass weight en_US
dc.subject dressing percentage en_US
dc.subject gamate rescue en_US
dc.subject linear body measurements en_US
dc.type Thesis en_US


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