Dea et al. J. Agri. Environ. Sci. 8(1), 2023
Publication of College of Agriculture and Environmental Sciences, Bahir Dar University 73
Research Article
Phenotypic characterization of the Gamo highland sheep population in Gamo Zone, South
Ethiopia
Dereje Dea
1*
, Ermias Eramo
1
, Deribe Gemiyo
2
1
Arba Minch Agricultural Research Center, Arba-Minch, Ethiopia
2
Southern Agricultural Research Center, Hawassa, Ethiopia
Corresponding author: deredea12@gmail.com
Received: September 25, 2022; Received in revised form: May 4, 2023; Accepted: May 5, 2023
Abstract: The study aimed to identify physical characteristics and prediction of live weight using linear body
measurements of indigenous sheep types in two highland districts of the Gamo zone (Chencha and Qogota).
Districts were purposively selected whereas farmers and animals were randomly selected. About 335 mature sheep
(270 female and 65 male) were sampled for the body measurements. Both qualitative and quantitative data were
analysed using SPSS version (20). Overall, the current findings revealed that mixed (62.50%) followed by black
(21.90%) were the dominant coat colours with patchy coat colour patterns (56.30%). The majority of the sheep were
horned (62.5%), curved horn (67.50%) and obliquely backward horn types (77.50%). Horizontal ear orientation
(76.00%) and straight head profile (96.90) were predominantly observed. In general, about 71.60% of the sheep
were hairy type and had straight crimp-curled hair (73.60%). The total hair coverage on the head, face, belly and
leg was about 3.0%, 94%, 92.5% and 13.4%, respectively. About 55.20% of the study sheep revealed near hocks tail
length. The mean body weight, body length, height at wither, chest girth, horn length, head length, hair length, ear
length and tail length were 20.26±3.60 kg, 54.55±3.48, 55.13±3.83, 66.73±4.79, 9.42±7.46, 16.83±1.85, 7.41±3.12,
10.27±0.97 and 26.62±2.66 cm, respectively. In general, sex, district and age (dentition) significantly (P<0.05)
affected linear body measurements. Body weight and most of the linear body measurements were positively
correlated. Chest girth was the single best predictor of body weight (P<0.05). Molecular characterization of Gamo
highland sheep is recommended for further advanced breeding strategies.
Keywords: Body weight, Chest girth, Highland sheep; Linear body measurement, Phenotypic traits
This work is licensed under a Creative Commons Attribution 4.0 International License
1. Introduction
The total sheep population in Ethiopia is estimated to
be about 42.9 million of this, and about 99.52% are
indigenous (CSA, 2021). The majority of the sheep
are found in the north western highlands of the
country (Solomon et al., 2008; Assen and Aklilu,
2012). Morphological and molecular
characterizations of sheep breeds in the country are
traditionally recognized by ethnic or geographic
nomenclatures. In Ethiopia, only a few breeds have a
fair description of their physical appearance
(Fsahatsion et al., 2018). Based on this, the sheep
breeds have been classified into 14 traditional
populations in 9 breeds within 6 major breed groups
(Solomon, 2008).
Identification and characterization of the existing
livestock genetic resources, their production
environment and constraints are crucial for long-term
Dea et al. J. Agri. Environ. Sci. 8(1), 2023
Publication of College of Agriculture and Environmental Sciences, Bahir Dar University 74
genetic improvement, to diagnose the status and
trends of the system and conservation (Getahun et al.,
2008; Zewdu et al., 2009; Aamir et al., 2010;
Sowande et al., 2010; Ibrahim and Isa, 2011; Asefa et
al., 2017). The classical description of breeds is
based upon phenotype because an organism’s
phenotype is principally a manifestation of its
genotype, and it lends itself to direct measurement of
the organism. As such, phenotypic characterisation is
therefore complementary techniques for measuring
genetic diversity (Fsahatsion et al., 2018).The
productivity of sheep as in the case of most ruminants
is markedly low due to several genetic and
environmental factors (Markos, 2006).
Information on the phenotypic traits of the Gamo
highland sheep population is limited despite its
contribution and role as a source of cash income and
improving food security in the highlands of the Gamo
zone. For a more detailed characterization study of
Gamo highland sheep; updating phenotypic
appearances by routine inventories and on-going
monitoring are vital since genetic resources and
production systems are not static. Hence, this study
attempted to physically characterize indigenous sheep
types in the Gamo zone, south region, Ethiopia.
2. Materials and Methods
2.1. Description of the study area
The study was conducted in two districts (Chencha
and Qogota) of Gamo zone Highlands of south
Ethiopia. Gamo zone is bordered on the south by
Dirashe special woreda, on the southwest by Debub
Omo zone, on the northwest by the Konta zone, and
on the north by Dawuro and Wolayta zones, on the
northeast by Lake Abaya and on the southwest by the
Amaro special woreda.
Chencha woreda is located in the Gamo zone of
the Southern region, 37 kilometers north of Arba
Minch. Part of the Gamo Zone, Chencha is bordered
on the south by Arba Minch Zuria, on the west
by Dita & Gofa on the north by Kucha and Boreda,
and on the east by Mirab Abaya. Chencha has a
longitude and latitude of 6°15′N and 37°34′E,
respectively and an elevation of 2732 meters above
sea level.
Qogota is one of the recently established woreda. It is
bordered on the south by Chencha, on the west by
Kucha, on the north by Boreda and on the east by
Mirab-Abaya woredas. Qogota woreda has an
altitude of 2569 meter above sea level with
6°17′26’’N and 37°32′46’’E.
Gamo highland areas are characterized by a mixed
farming system. The major crop types produced
include inset, barley, wheat, bean, pea and potatoes
(Dereje, 2020).
2.2. Sources of animals
Indigenous sheep type found in the study districts of
Gamo zone was used as experimental animals. Since
it is on farm characterization, animals in the hands of
farmers were used and data regarding body
measurement and morphometric characteristics were
collected early in the morning before the animal was
released for grazing.
2.3. Sample size and sampling techniques
The study districts were selected purposively based
on their highland agro-ecology and sheep population
potential whereas smallholder farmers were selected
randomly. For morphological characters (qualitative)
and body measurements (quantitative) about 335
sheep (270 female and 65 male) from 70 households
were selected based on sex and age of animals.
Pregnant females (ewes) were excluded from the
sampling because pregnancy has an influence on
body parameters. Each experimental animal was
identified by sex, site and estimated age group. All
age groups of the sheep were classified into five age
groups using the number Pairs of the Permanent
Incisors (PPI): (0PPI, 1PPI, 2PPI, 3PPI and 4PPI) as
indicated in Table 1 (ESGPIP, 2009).
Sheep sample size was determined based on the
formula [1] described by Mezgebu et al. (2022).
[1]
Where;
n = required sample size
N = population size
e = error margin (e = 0.07)