Phenotypic characterization of indigenous Maefur goat population in Tigray, Northern Ethiopia

The study was conducted in Erob district eastern Tigray, Ethiopia to phenotypic characterize Maefur goat based on physical body feature and linear body measurements. Six hundred (297 male and 303 female) goats were randomly selected and grouped into four age groups of 0, 1, 2 and ≥3 PPI. General Linear Model (GLM) procedure of SPSS version 16.0 and descriptive statistical analysis were were used to summarize the collected data. Short ear size (12.3 cm for male and 11.8 cm for female), long and thick horn, medium body size (42.8 kg for male and 32.7 kg for female), and large heart girth (82.1 cm for male and 73.4 cm for female) are the major body characteristics of Maefur goat breed. There was a significant (P< 0.05) effect of sex and age on live body weight and linear measurements. Mean± SE of live body weight, heart girth, body length and height at wither in male were 34.7±0.57 kg, 75.3±0.53 cm, 64.3±0.61 cm and 64.7±0.46 cm, respectively while in female 28.9±0.35 kg, 70.0±0.33 cm, 60.0±0.40 cm, and 59.3±0.31 cm, respectively. For heart girth in these age groups were 61.1±0.53, 69.4±0.33, 70.6±0.4 and 77.7±0.39 cm, respectively while body length were 50.3±0.43, 56.8±0.42, 59.3±0.58 and 68.2±0.42 cm, respectively. For height at wither in these age groups were 54.0±0.45, 59.1±0.35, 58.4±0.32 and 66.5±0.40 cm, respectively. Heart girth and height at wither were significantly (P<0.05) different among the age groups except between 13-18 and 19-24 months. The study revealed that large heart girth is a unique characteristic of the Maefur indigenous goat. The study concluded that Maefur goat breed is identified as one of the potential goat breed in Tigray, Ethiopia.


INTRODUCTION
The day to day livelihood activity of smallholder farmers depends on the agricultural practices in almost all part of Ethiopia.The contribution of agriculture in Ethiopian accounts for more than 40% of the national GDP, 90% of exports, and serve as source of income and basic needs to more than 90% of the poor farmers (Diao, 2010).Ethiopia is endowed with huge livestock biodiversity adapted to varied agro ecological conditions.Among the farm animal genetic resources, indigenous goats have unique adaptive mechanisms which enable them to fit in varied agro ecologies and contribute to the livelihood of small holder farmers through producing valuable milk and meat products.Within the agro ecology there are also sub agro ecologies and developed in to niches as home of specific adapted ecotypes.Kolo et al. (2015) described the domestic goat (Capra Aegagrus) as a subspecies of goat domesticated from the wild goat of southwest Asia and Eastern Europe.FARM-Africa (1996) described the origin and historical distribution of the highland indigenous goat population of Ethiopia that emphasized on documentation of the goat breeds.The institute of biodiversity conservation (IBC) documented fifteen (15) indigenous goat breeds inhabited in the low land, midland, and highland agro ecologies of Ethiopia (IBC, 2004).The total population of goat in Ethiopia are reported as 24.06 million of which 99.99% are indigenous goat breeds (CSA, 2013).To ensure sustainable utilization of the indigenous goat, there should be a conservation strategy for the present and future use.Phenotypic characterization is the first step for identification of qualitative and quantitative traits of the indigenous goat.An accurate description of Maefur goat kept under extensive management conditions would enable an accurate comparison of this breed with other goat breeds and improvement programs can then be developed using such information.Body weight and linear body measurements determine body size which is important to classify goat breed into groups.Based on height at wither and body weight, indigenous goat in Ethiopia are classified in to three classes (large, >65 cm and weighing 37-50 kg; small, 51-65 cm and weighing 26-36 kg; dwarf, <50 cm and weighing 18-25 kg) (Kassahun and Solomon, 2008).The improvement on local goat depends on the phenotypic information for mass selection, whereby individuals with better trait values is chosen to be parents of the next generation (Carneiro et al., 2010).Maefur goats population is one of the potential indigenous goat breeds found in the regional government of Tigray but not yet well described with limited attempts to characterization for sustainable utilization and designing management intervention under smallholder farmer.Hence identifying and characterizing Maefur indigenous goat population is very important to integrate animals into various production systems and to make effective use of their potential.The objectives of this study were to phenotypic characterization of the indigenous Maefur goat population using linear body measurement (LBM) and physical body characteristics and to evaluate the effect of sex and age on body weight and LBM under extensive management conditions.

Description of the study area
The study was conducted in Erob district found 47 km northeast of Gebreyowhens and Kumar 131 Adigrat in the eastern zone Tigray.It is located at 14010' to 140 25 'N and 390 40' to 390 50'E (Tesfay et al., 2011).The max and min annual temperature ranges from 25 to 30°C and 12 to 16°C, respectively.Mean annual rainfall ranges from 250 to 300 mm during the rainy months of June and August (EAZT, 2005).The study area covers an altitude ranging between 1200 and 3000 m above sea level (Tesfay et al., 2011).It has also notable topographic features including the "Ayga" (Appendix Figure 2) and "Assimba" mountains (Appendix Figure 3).

Sampling procedure
Purposive sampling of the district and potential PA was used because of the existence of the potential indigenous goat population named as Maefur DAGRIS ( 2004) and the information about their distribution in the regional government of Tigray is already reported by Tigray Agricultural Research Institute but no one tried to reach them for phenotypic characterization.About 600 randomly selected indigenous goats of 49.5% male and 50.5% female goats were used during phenotypic characterization.The variables measured included live weight recorded using Salter scale with capacity of 50 kg (accuracy nearest 200 g) and linear body measurements using meter tape (1.5 meter and accuracy 0.5 cm).Age of the sampled animals was determined using dentition as recommended by Solomon (2009) and Wilson and Durkin (1984).The selected animals were grouped into one of the following age categories: 0 PPI (04 to12 month with 46 male and 36 female, 1 PPI (13 to 18 months) with 47 male and 40 female, 2 PPI (19 to 24 months) 57 male and 77 female, and ≥3 PPI (25 to 36 months and above) with 147 male and 150 female.Linear body measurements recorded for each study animal were heart girth, height at withers, height at rump, shoulder width, chest depth, body length, ear length, ear width, horn length, head width and head length.

Procedures of recording body measurements
The coat color (using color chart) and pattern, shape and orientation of the horns and ears, size of tail, and profile of head, back and rump can be recorded using coded descriptors (FAO, 2012).Descriptive information should be recorded on the common flock sizes and structures as well as uses.

Recording LBM
Linear body measurements (LBM) were recorded in the morning before the animals are fed, with the animals standing on a flat surface with head held up (Appendix Table 1).Hanging spring scale was used to measure body weight (BW) to the nearest 0.1 kg.Heart girth (HG) was measured by taking the circumference of the chest using a tailor's tape calibrated in cm, taken as the circumference of the body immediately behind the shoulder blades in a vertical plane, perpendicular to the long axis of the body.Height at wither (HW) was measured as the distance from the ground to the withers.Height at rump (HR) is measured as the distance from the ground to the rump.Shoulder width (SW) was measured as a distance between the shoulders.Chest depth (CD) was measured as the distance between the top behind the scapular and the flow of the sternum (taken to be the depth of brisket) immediately behind forelegs.Body length was the distance from the head of humerus to the distal end of the pubic bone.

Statistical data analysis
Different analysis methods were applied using SPSS version 16.0 software program.Live body weight and linear body measurements were subjected to List-square analysis of variance using the General Linear Model (GLM) procedure of SPSS version 16.0 with sex and age as fixed effects.The Tukey's simultaneous test was used to separate significance of least-square means.Physical body traits were analyzed using descriptive analysis for mean and standard deviation (quantitative data) and frequency (qualitative) of the variables.
Where:Yij = the observation of the i th animal within the j th age of i th sex; µ = overall mean; Si = effect of the i th sex (male and female); Aj = effect of j th age (04-12, 13-18, 19-24, and 25-35 months and above); Lij = interaction effect of the i th sex and j th age groups, and Eij = Random error factor.The effect of sex, age and their interaction on live body weight and linear body measurements were determined at 5% level of significance.Least-squares means for sex and age groups were separated using Student's t-test and Duncan's Multiple Range Test (DMRT), respectively.The difference between and among the least squares means was determined at 5% level of significance.Indices were calculated in the excel Microsoft to provide ranking of the observed body and head color.Index = Sum of [4 for tick + 3 for rank 1 + 2 for rank 2+1for rank3] for each color divided by sum of [4 for tick + 3 for rank 1 + 2 for rank 2+1for rank3] for each color

Physical body characteristic of the indigenous Maefur goat population
The study observed variety of coat pattern in Maefur goat population.The overall coat color pattern of the sampled goat was described as spotty (32.3%), pied 27%, uniform (25%) and shaded (light brown, black, and gray) (15.3%) (Table 1).Medium (1-2 mm) (64%) and short (29.3%) hair length were the overall description of the indigenous Maefur goat population.Short, narrow, thin, and laterally oriented ear (92% of incidence) was the overall characteristic of Maefur indigenous goat breed.This observation of the current study revealed that Maefur goat has dominant lateral ear orientation distinguished from Begait goat with dropped ear orientation.Solomon (2009) stated that ear orientation and size are important for discrimination of more related indigenous goat breeds.The overall descriptions for horn orientation of the observed indigenous Maefur goat breed were backward (45%) and upright (41%), respectively with frequently observed straight (81%) and spiral (18%) horn shapes.The overall body shape characteristics of the sampled Maefur goat breed was in-between with 76% and lanky with 20% (Figure 1).The dominant body shapes (inbetween leggy and compacted) had some implication to distinguish Maefur indigenous goat from 12 indigenous goat breed of Ethiopia documented by DAGRIS (2004) and Kassahun and Solomon (2008).Concave (83%) and flat (straight 16%) facial profiles were the most descriptor for the overall facial profile of Maefur goat breed.
Body color of the indigenous Maefur goat was assessed using randomly selected 750 goats 5 goats from each 150 household (Appendix Figure 1).The most frequently observed body coat color was beige, black and brown with an index value of 0.30, 0.20 and 0.18 (Table 2).Figure 2 illustrates the variety of morphological characteristics of Maefur goat flock.The smooth hair type with spotty coat color, long horn (straight and spiral) and sometimes polled in male), short ear size, straight facial profile and potential for meat improvement are the most important physical characteristics of the indigenous goat population.It has its own distinguishing feature and local name apart from the afar goat.Afar goats are characterized as small breed in Ethiopia (Solomon, 2009).The afar goats are recognized with local name of Adal in Afar region and widar (dwarf) in the border area of Tigray brought to be sold in Mekelle city for meat purpose.Maefur and Afar goat populations are distinct in phenotypic performance (Maefur has larger body size than afar goat) but they have some similarities in the coat color patterns (Figure 2 and Appendix Figure10).

Body weight and linear body measurement in Maefur goat
Table 3 summarized the least squares means for live body weight and body measurement in different age groups and sex for the Maefur goat breed.The main source of variation on live body weight and linear body measurement were sex, age and the interaction of both sex and age.

Effect of age, sex and their interaction on body weight and linear body measurements
There was a significant (P < 0.001) variation for live body weight, heart girth, height wither, height at rump, shoulder width, body length, chest depth, horn length, tail length, head width and head length among the four age groups (04-12, 13-18, 19-24 and 25-35 months) but no significant (P>0.05)variation for ear length and ear width among these age groups.The variation for live body weight, heart girth, height withers, height at rump, shoulder width, body length, and chest depth was also significant (P < 0.001) between male and female but no significant (P>0.05)variation for horn length, tail length, ear length, ear width, head width and head length for interaction of sex and age group.The report of this finding is in line to the findings reported by Khan et al. (2006) andFajemilehin andSalako (2008) and Alemayehu et al. (2012).
According the east Africa goat size classification method, body size of the goat breed is categorized in to three groups: Small (20-30 kg), medium (30-45 kg) and large (45-60 kg) (Kiwuwa, 1992).Accordingly, Maefur goat is classified as medium sized indigenous goat.Saanen goat is a large goat breed with average live body weight of 65 kg for male and 50 kg for female (Pesmen and Yardimci, 2008).Therefore, live body weight is among the production trait used to classify goat population in to breed standard and are important in giving information about the morphological structure and development ability of the animal (Kiwuwa, 1992, Hassen et al., 2012;Riva et al., 2002).Ethiopian goats are classified according to the body weight and height at wither.Based on the average adult age (25-35 months), both male and female Maefur goats have medium body size.

Heart girth
The average heart girth of Maefur male goat in four age groups (04-12,13-18,19-24 and 25-35 months) were found to be 61.9±3.8,69.9±3.2, 72.8±4.7 and 82.1±6.3 cm while that of female in these age groups were investigated to be 59.9±5.8,68.7±2.7,69.0±4.1 and 73.4± 3.2 cm, respectively.Significant (P<0.05)difference was reported in heart girth between male and female goat within age group 3 and 4.There was no significant (P>0.05)difference in heart girth between male and female in the age group of 1 and 2. The average heart girth 82.1 cm for male and 73.4 cm for female adult Maefur goat breed was higher than that of Abergelle reported as 68.67 and 64.44 cm for adult male and female, respectively (Alemayehu et al., 2012).Body size of the adult goat is the indication of heart girth, body length, height at wither and height at rump.Among these major linear body measurement heart girth is widely used to classify physical characteristic of Ethiopian goat families and breeds (Solomon, 2009).Adult female Maefur goat with an average value of heart girth 73.4 cm had comparable size with Western Highland goats with 75.8 cm classified as large whereas Afar goat with average heart girth 67.4 cm are classified as small indigenous goat in Ethiopia (Solomon, 2009).

Height at wither
The average height at wither of Maefur male goat in four age groups (04-12, 13-18, 19-24 and 25-35 months) were determined as 55.5±3.9, 59.4±2.8,60.9±3.1, and 70.8±6.1 cm while that of female in these age groups were recorded to be 52.2 ± 3.7, 58.7± 3.8, 56.6±3.1 and    4).Significant (P<0.05)difference was reported in height at wither between male and female goat within age group 3 and 4.There was no significant (P>0.05)difference in height at wither between male and female between age group of 1and 2. The stage of growth and development might musk the difference between male and female at early age.

62.3±4.6 cm, respectively (Table
The adult female (25-35 months) Maefur goat breed with 62.3 cm height at wither is in between the Afar and Western Highland goat breed as 60.9 and 70.8 cm, respectively (Solomon, 2009).Both male and female adult Maefur goat with average height at wither 70.8 and 62.3 cm, respectively are larger than the Abergelle goat reported as 61.05 and 59.44 cm, respectively for adult male and female (Alemayehu et al., 2012).According to the classification criteria using height at wither and body weight for body size of Ethiopia indigenous goat suggested by Kassahun and Solomon (2008), there are three classes: large, >65 cm and weighing 37-50 kg; small, 51-65 cm and weighing 26-36 kg; dwarf, <50 cm and weighing 18-25 kg).Therefore, both male and female Maefur indigenous goats are classified as large body size.

Body length
The average body length of Maefur male goat in four age groups (04-12, 13-18, 19-24, and 25-35 months) were recorded to be 51.0±4.1, 56.2±4.0,61.8±6.8, and 72.3±7.1 cm while in female in these age groups were 49.4±3.6, 57.5±3.7, 57.6±6.4, and 64.3±5.0 cm, respectively.Significant (P<0.05)difference was reported in body length between male and female goat within age group 3 and 4.There was no significant (P>0.05)difference between male and female in the age group of 1 and 2. Both male and female adult Maefur goat with average body length 72.3 and 64.3 cm, respectively are larger than the Abergelle goat reported as 53.00 and 52.03 cm, respectively for adult male and female (Alemayehu et al., 2012).The faster growth of male goats Gebreyowhens and Kumar 137 than females at early stage is suggested because of the hormonal effect that is non-release of androgen (which is known to have growth and weight -stimulating effects) in male animals until the testis are well developed (Frandson and Elmer, 1981).Therefore, male goats are heavier and larger than female goat.

Horn length
The average horn length of Maefur male goat in four age groups (04-12, 13-18, 19-24 and 25-35 months) were determined to be 11.4±3.5, 16.7±4.1,13.3±2.1 and 19.3±6.3 cm while in female in these age groups were 9.9±5.0,13.4±3.5,15.0±4.3 and 15.6±4.2cm, respectively.Significant (P<0.05)difference was reported in horn length between male and female goat within age group 2, 3 and 4 whereas there was not significantly (P> 0.05) differed in age group 1. Maefur indigenous goat has medium sized and thick horn with some times spiral shape pointed upward for male whereas for female, short, thick, straight, and backward oriented horn.

Effect of sex on body weight and linear body measurements
The LSM of body weight, heart girth, height wither, height at rump, shoulder width, body length, chest depth in male were 34.7±0.57kg, 75.3±0.53cm, 64.7±0.46 cm, 64.8±0.34 cm, 11.3±0.12cm, 64.3±0.61cm, and 8.7±0.18cm, respectively (Table 5).The LSM for these measurements (same order) in females were 28.9±0.35kg, 70.0±0.33cm, 59.3±0.31cm and 59.2±0.27cm, 10.2±0.11cm, 60.0±0.40 cm, and 7.2±0.15cm, respectively.There was significant (P<0.05)difference between male and female LSM value of these measurements.Considering the LSM value of the live body weight and the major linear body measurement like heart girth, height at wither, body length and height at rump, the study revealed that male goat are heavier and larger than female goat at 95% level of confidence.This result of the current study is in line to the findings of Hassan and Ciroma (1990) in the Red Sokota goat breeds.

Effect of age on body weight and linear measurements
There was a significant (P<0.05)difference both in live body weight and linear body measurements among the four age groups (04-12, 13-18, 19-24 and 25-35 months) of Maefur goat breed (Table 6).Superscripts (a), (b), (c) and (d) are used to indicate the order of the difference from larger (a) to small (d) mean value respectively at 5% level of significance with larger mean (a) and smaller mean (b) otherwise similar superscripts (either of these letters) connected for non-significant pair of difference.
The LSM value of live body weight in four age groups (04-12, 13-18, 19-24 and 25-35 months) were 19.6±0.4,27.6±0.3,and 29.3±0.4 and 37.5±0.4kg, respectively.This result is however not surprising since the size and shape of the animal is expected to increase as the animal is growing with age.There was wide variation as the age of the animals increased in the live body weight.This result is in line to the finding of Khan et al. (2006) andAlemayohu et al. (2012).However, the variability among the age group at maturity sharply reduced between age groups (Fajemilehin and Salako, 2008).In some linear measurement, the difference between age group 2 and 3 was not significant as the body condition of the animal affects the consistent growth of the animal and then the measurements (Devendra and Burns, 1983).Most of the linear body measurement of the sampled indigenous goat significantly (P<0.05)increased with age, the older animals (25 months and above) being heavier and larger than the kids (04-12 months), with the growers being intermediate.The current study observed that growth rate from 0 to 1 PPI was higher than as compared to that from 1 to 2 PPI and 2 ≥ 3PPI in live body weight of the highland sheep population (Figure 3).

Conclusion
Maefur indigenous goat populations adapted to the mountainous topographical features and survived through utilizing browsed indigenous plant species around the hillside of Erob district eastern Tigray.The analyses of data on body measurements provide quantitative measure of body size and shape.Body measurements provide quantitative measure of body size and shape.It has an identified body characteristic from other indigenous goat found in the regional government of Tigray by its conformation (rectangular shape), large heart girth (82.1 cm for adult male and 73.4 cm for adult female), thick and long horn in male, variable coat color and concave facial profile.Accordingly, the indigenous Maefur goats breed is characterized as medium-size breeds (42.8 kg for adult male and 32.7 kg for adult female).Based on this evidence, male goat is larger than female goat.It has distinguished feature from Afar (dwarf goat) by its large size (has large heart girth) in between the compacted and leggy body confirmation.Afar goat is in habited in the regional government of Afar around the lowland but Maefur is inhabited in the mountainous highland area of Tigray.In addition, to increase the validity of this on farm preliminary study, it is important to undertake well planned on station study for phonotypic and genetic characterization of the goat under study within breeds and then to improve their genetic potential.Community based breed improvement through selection should be designed for proper mating superior male and female goat.It is better to make a group of households of the same village in a local, small-scale community-based indigenous goat breeding organization.

Figure 3 .
Figure 3.Effect of age on live body weight in relation to growth rate in Maefur goat.
for 04-12months=A, for 13-18 months=B, for 19-24months=C and for 25-35 months= D For age grouping use milk and permanent teeth pair (milk teeth= Group A, for 1pair of permanent teeth=Group B, for 2 pair of permanent teeth=Group C and for >=3pair of permanent teeth =D).BW=Body weight, HG=Heart girth, HW=Height at wither, RH=Height at Rump, SW=Shoulder width, BL=Body Length, CD=Chest Depth, E L=Ear length, Ew=Ear Width, HL=Horn length and TL=Tail length.

Figure
Figure 3. Walking down hill towards the targeted HH

Figure 10 .
Figure 10.Maefur goat flock in the study area.

Table 1 .
Morphological features of Maefur goat population.

Table 2 .
Ranked body color of Maefur goat breed in the study site.
Alemayehu et al. (2012)±4.1 and 42.8± 6.6kg, respectively while that of female in the same age groups were noted as 18.5±4.4,26.4±2.9,27.9±4.59,and32.7±4.1 kg, respectively (Table4).Significant (P<0.05)difference was found in live body weight between male and female goat in all age groups.This finding of the current study is agreed with the report ofKhan et al. (2006)andAlemayehu et al. (2012).The average live body weight of Maefur goat was 42.8 and 32.7 kg for adult male and female goat, respectively.For pooled sex

Table 3 .
MANOVA for live body weight and linear body traits of the indigenous Maefur goat.

Table 4 .
Mean value± (SD) of the linear body measurement and body weight.

Table 5 .
LSM± (SE) of the live body weight and linear body measurements for pooled age.

Table 6 .
LSM (±SE) for body weight and body measurements for goats of pooled sex.

Table 1 .
Data collection format for linear body measurement (LBM).