IN PARTIAL FULFILLEMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTERS OF SCIENCE IN ANIMAL GENETICS AND BREEDING

Abstract

Ethiopia has huge indigenous goat populations that are adapted to diverse agro ecological and production habitats across different parts of the country. In Ethiopia, indigenous goats play a crucial role in the social, economic, and cultural realm of the country for the resource-poor rural communities. This study was aimed at identifying and describing the peculiar phenotypic features of indigenous goats and community husbandry practice in Arba Minch Zuria, Garda Marta, Kucha Zuria, and Geressie Zuria districts of the Gamo Zone. Data on general goat husbandry, breeding practices, and prevailing constraints were collected through a field survey of 180 households. Furthermore, phenotypic features data from 813 adult goats were gathered through direct observation of physical features and measurements of morphometric traits. A total of 813 adult indigenous goats were selected, comprising of 212 intact adult bucks and 601 non-pregnant adult does. Age was estimated through dentition, with goats having two pair permanent incisor, three pair permanent incisor, and four pair permanent incisor were included in the study. Both qualitative traits (coat colour pattern, coat colour type, body skin color, hair type, hair length, horn presence, horn shape, horn orientation, ear orientation, facial profile, wattles, beard, hair on thigh, hair on abdomen, back profile, and rump profile) and morphometric measurements (body weight, body length, chest depth, chest girth, height at withers, height at rump, rump length, rump width, horn length, shin circumference, head length, head width, ear length, scrotum circumference, teat length, tail length, muzzle diameter, and udder circumference were recorded in their existing production environments. All collected data analyzed by using SAS version 9.0 (2002). Mainly the qualitative traits were studied by means of cross tabs. Reproductive performance traits were analyzed by one-way ANOVA using the DMRT mean comparison test, with districts as the main factor, and the analysis was carried out separately for both sexes. Moreover, quantitative traits were analysed by two-way of ANOVA using the DMRT mean comparison test, with age, sex, and districts as main factors, and the analysis was carried out separately for both sexes. The results are presented in a table with reliable figures. The findings revealed that households were headed by males in 96.11% of cases. Around 37.78% of households’ heads were illiterate, with 60.55% of them belonging to the young age group. Furthermore, approximately 95.56% of households were engaged in mixed farming activities. The primary reasons farmers keep indigenous goats were for meat production, the sale of live animals, and as a means of saving money. Both hillsides and communal grazing land are prominent feeding sources. Rivers are the main water source during both dry and wet seasons. The major diseases in the study districts were of the study districts (Peste des Petits Ruminants) PPR, (Contagious Caprine Pleuropneumonia) CCPR, and foot rot. However, indigenous goats were identified as being completely unaffected by trypanosomiasis. The major mating practice was natural and uncontrolled. The major preference for selection criteria was body size for bucks, while litter size was the major preference for does. Moreover, the majority of goat keepers were practiced both castration and culling. On the other hand, the majority of goat keepers reported that the primary challenges were the prevalence of disease, the presence of predators, and the lack of infrastructure. A total of sixteen morphological traits were observed, the majority of these traits were significantly different (P<0.05) across the study districts, with the exception of coat color pattern, which was not significant different (P>0.05). The most common coat color pattern class was plain (67.04%), followed by black (18.33%) out of a total of nine distinct coat color xi type classes. Eighteen morphometric measurements were also recorded, all of which were found to be highly significantly different (P<0.0001); furthermore, district, sex, and dentition effects were all found to be significant (P<0.0001). However, the interaction effects of sex and age of the most morphometric measurements were not significant (P>0.05) on body weight, body length, chest depth, chest girth, height at wither, height at rump, horn length, head length, ear length, and shin circumference, while some were significant (P<0.05) on head width, rump length, rump width, tail length and muzzle diameter. Likewise, the interaction effects of sex and districts of the most morphometric measurements were not significant (P>0.05) on body weight, rump width, horn length, ear length, tail length, and shin circumference, while some were significant (P<0.05) on body length, chest depth, chest girth, height at rump, height at wither, rump length, head length, head width, and muzzle diameter (P<0.05). Correlations between body weight and linear body measurements were found to be significant (P<0.0001) except tail length in both sexes. Linear body measurements were used to predict body weight. The prediction equation for bucks was BW = -9.46 + 0.54 chest girth, with an adjusted R2 value of 0.46. The prediction equation for does was BW = -21.78 + 0.70 chest girth, with an adjusted R2 value of 0.58. Canonical discriminant analysis (CANDISC) revealed that quantitative traits and the Mahalanobis distance between study districts were significant (P<0.0001), suggesting distinct phenotypic variations among goats in the studied districts. Twenty structural indices were calculated to determine the type and function of indigenous goats, all of which were found to be significant (P<0.0001). According to the length index and proportionality index, all districts were identified as having dairy-type goats, with the except for Geressie Zuria district in the proportionality index. However, the dactyl thorax index, compact index, longitudinal pelvic index, relative depth of thorax index, and pelvic index indices clearly indicated that all districts had meat-type goats with long legs. This basic information is crucial for designing efficient breeding programs, formulating policies, and conserving genetic resources. Nevertheless, further investigations, including monitoring and molecular characterization, are required to determine the genetic diversity of these goats. Key words: Breeding and management practices, Gamo zone, indigenous goat, morphological variation, phenotypic characterization