# Phenotypic Characterization and Reproductive Performance of Blackhead Somali Sheep in Fafen Zone of Somali Regional State, Ethiopia

Authors: Abdimalik Hussein Mohamed; Berihu Gebrekidan; Niraj Kumar; Haben Fesseha Gebremeskel; Mesfin Mathewos Abose
Journal: Advances in Agriculture
 (2022)

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## Abstract

Objective. The study aimed to characterize the reproductive performances and physical characteristics of Blackhead Somali indigenous sheep breeds. Methods. The data from 460 sheep were used for the determination of morphometric characterization while 110 male sheep and 150 females were used to characterize the reproductive performance of Blackhead Somali sheep breeds. Results. Accordingly, about 86% of sheep have a white body with a blackhead as the dominant coat color and about 81% of sheep have a straight facial head profile. Dewlap was present in 92.7% (91.8% for males and 92.7% for females). The overall average body weight, body length, height at wither, height at the rump, heart girth, chest depth, pelvic width, and tail circumference differs significantly (p<0.05) among males and females with the advancement of age. The average age at first service, age at first lambing, lambing interval, and life lamb crop in ewe were 13.75 ± 2.44, 19.12 ± 2.41, 9.66 ± 1.56, and 6.18 ± 2.01, respectively. The average reproductive life span of ewe and ram was 6.04 ± 1.43 and 6.63 ± 1.49 years, respectively. On average Blackhead Somali ewe delivers 13.1 ± 4.3 lambs in her lifetime. The twinning and triplet rate were recorded to be 12.30% and 1.90%, respectively. Conclusion. In conclusion, shorter lambing intervals, higher adult body weight, and frequent twinning are the most desirable features which may also be used as selection criteria. It is recommended to do further detailed analyses to determine the genetic variation between and within these small populations to develop an effective conservation and utilization program.


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## Body

## 1. Introduction

Cattle, sheep, goats, and equines make up the majority of Ethiopia’s livestock, and they are all well suited to a variety of environmental circumstances. Sheep are among them, and they are found all over the country in various agroclimatic conditions. Ethiopian sheep production is based on indigenous breeds, which make up approximately 99.72% of the country’s total sheep population [1] and the livelihood of people in low-input, smallholder, and pastoral production systems [2].About 14 traditionally recognized sheep populations may be found in the nation; they are divided into nine genetically unique breeds among six primary breed groupings, which are dispersed across various ecological conditions, production methods, and communities or ethnic groups [3]. Ethiopia has 30.70 million sheep, of which about 75% are located in the highlands where mixed crop-livestock production systems are predominant, and 25% are located in the lowlands [1, 4].Farmers can choose stocks or create new breeds thanks to animal genetic variability in reaction to environmental changes, disease threats, updated understanding of human nutritional demands, shifting market situations, and societal needs, all of which are mostly unpredictable [5]. Profit can be significantly boosted by choosing the proper animal, with no modifications to nutrition, health, or other inputs. On the other hand, choosing the wrong breed or crossbreed might lead to losses. An essential component of the production system is the choice of germplasm, which must be carefully matched to the other inputs available [6].Breed characterization is crucial for the effective use and preservation of farm animal genetic resources. Lack of sufficient knowledge about breed features may cause genetic degradation through crossbreeding, replacement, and dilution. All efforts connected to the description of animal genetic resources that aim to further our understanding of these resources and their state are included in the characterization of animal genetic resources [5]. The phenotype serves as the foundation for the traditional descriptions of breeds (such as coat color, horns, tail type). In addition to the potent biotechnological tools for assessing genetic variation at the genome level, phenotypic characterization can be useful.The Borana plain and other arid and semiarid regions of southeast Ethiopia are home to a sizable population of Blackhead Somali sheep. The breed is highly suited to semi-arid and dry environments, where they may thrive on subpar feed in desert grazing terrain. The major purpose of raising the animal is to provide meat. The predominant coat color was blackhead with a white body, and the breed has a big frame. Dewlap, a skin extension, is fully developed and wattle is missing. Both sexes exhibited horn absence and a predominately horizontal ear position. The body measurement information serves as the foundation for developing more sophisticated characterization, conservation, breeding, and selection techniques for indigenous sheep breeds [7, 8] and is used to assess the type, function, and value of the animal as potential breeding stocks [9].Several studies have been conducted to characterize Ethiopian sheep breeds. The Blackhead Somali sheep is a Somali indigenous sheep breed. Despite its contribution and role as a source of cash income and improving food security, information on phenotypic traits, and reproductive performance of sheep types are limited. Since genetic resources and production systems are dynamic, routine inventories and ongoing monitoring are necessary if previous works have been claimed to have been carried out [10]. However, information on the descriptions of the body measurements of native Ethiopian sheep and Blackhead Somali sheep is still lacking. It has therefore been necessary to conduct a more thorough phenotypic characterization study of Blackhead Somali sheep in the study area. Thus, the objective of this study was to characterize the reproductive performances and physical characteristics of Blackhead Somali indigenous sheep breeds in the study area.


## 2. Materials and Methods

### 2.1. Study Area

The study was carried out in 21 peasant associations of 3 districts namely Jigjiga, Awbarre, and Kebribeyah in the Fafen zone, Somali regional state, Ethiopia. The selected regions were arid and semi-arid regions of southeast Ethiopia since it is home to a sizable population of Blackhead Somali sheep breeds. JigJiga is located approximately 80 km east of Harar and 60 km west of the border with Somalia and located at a distance of 628 km east of Addis Ababa. Geographically, JigJiga is found at a latitude and longitude of 9°21′N and 42°48′E, respectively and is characterized by unreliable and erratic rainfall with precipitation ranging from 300 to 600 mm per annum, a high ambient temperature of 30°C, this is arid and semiarid lowlands lying at an elevation of 500–1500 m above sea level. The 3 woredas have almost the same geographic position with similar sheep-rearing practices. The people in this area are agro-pastoralists and their lives depend on both agriculture and livestock. Blackhead Somali sheep is a native breed of the study area [1].


### 2.2. Study Animals

Study animals included 460 Blackhead Somali sheep that were kept in and around 21 locations in the Jigjiga, Awbarre, and Kebribeyah districts of the Somali regional state of Ethiopia. The information was gathered from organized Blackhead Somali sheep farms as well as smaller Blackhead Somali sheep farms that sheep producers in and near the study areas maintained. Also, the Blackhead Somali sheep is solely the study animal.


### 2.3. Sampling Method and Data Collection

Before data collection began in each sampling unit, farmers were given a briefing on the study’s goals and engaged in a random, open-ended discussion. Observations and measurements made on the ground as well as secondary sources were used to gather the data. Blackhead Somali sheep organized farm and the sheep farmers rearing Blackhead Somali sheep were purposively selected. Only those sheep were chosen from among sheep farmers whose record of age was kept by the farmers. For morphometric characterization, 460 sheep of both sexes were used; however, the reproductive performance of 110 male and 150 female breeding sheep was determined.


#### 2.3.1. Qualitative and Quantitative Data

Data on both qualitative and quantitative linear body measurements were gathered following the Food and Agriculture Organization’s suggested descriptor lists [11]. Since the animals’ posture, movements, and gut contents can affect body measurements, all the information was collected early in the morning. With just the naked eye, morphological characteristics such as coat type and pattern, head profile, ear orientation, wattle, horn, back and rump profile, and tail type were examined. Body measurements (in cm) such as body weight (BW), pelvic width (PW), heart girth (HG), body length (BL), height at rump (HR), height at wither (HW), tail circumference (TC), tail length (TL), scrotal circumference (SC), ear length (EL), and chest depth (CD) were measured using tailors measuring tape with records taken to the nearest cm after restraining and holding the animal in an unforced position. To reduce postprandial gastrointestinal fluctuation, body weight was recorded in the morning before the animals were released for eating. This was performed using a suspended spring balance with a 50 kg capacity and a 0.2 kg precision.The record was kept at the Blackhead Somali sheep organized farm and an interview with the farmers rearing Blackhead Somali sheep was used to gather data for characterizing reproduction qualities, which were then included in the datasheet. Data on reproductive features, including the age of the ram and ewe at first service, the age at first lambing, the interval between lambing, the ewe and ram’s reproductive life span, the longevity of the lamb crop, twinning and triplets, and mortality up to 90 days, were gathered.


### 2.4. Data Management and Statistical Analysis

The morphological and qualitative data were gathered and entered into the Microsoft Excel spreadsheet. Individual observation qualitative data were evaluated using SAS version 9.1.3’s frequency techniques (2008). Quantitative variables were analyzed using the SAS general linear model (GLM) technique. Body weight and a linear body measurement other than scrotum circumference were fitted as dependent variables, with sex and age groups fitted as fixed independent variables. When there was a significant difference (p<0.05), Tukey’s test was applied to separate the means.


## 2.1. Study Area

The study was carried out in 21 peasant associations of 3 districts namely Jigjiga, Awbarre, and Kebribeyah in the Fafen zone, Somali regional state, Ethiopia. The selected regions were arid and semi-arid regions of southeast Ethiopia since it is home to a sizable population of Blackhead Somali sheep breeds. JigJiga is located approximately 80 km east of Harar and 60 km west of the border with Somalia and located at a distance of 628 km east of Addis Ababa. Geographically, JigJiga is found at a latitude and longitude of 9°21′N and 42°48′E, respectively and is characterized by unreliable and erratic rainfall with precipitation ranging from 300 to 600 mm per annum, a high ambient temperature of 30°C, this is arid and semiarid lowlands lying at an elevation of 500–1500 m above sea level. The 3 woredas have almost the same geographic position with similar sheep-rearing practices. The people in this area are agro-pastoralists and their lives depend on both agriculture and livestock. Blackhead Somali sheep is a native breed of the study area [1].


## 2.2. Study Animals

Study animals included 460 Blackhead Somali sheep that were kept in and around 21 locations in the Jigjiga, Awbarre, and Kebribeyah districts of the Somali regional state of Ethiopia. The information was gathered from organized Blackhead Somali sheep farms as well as smaller Blackhead Somali sheep farms that sheep producers in and near the study areas maintained. Also, the Blackhead Somali sheep is solely the study animal.


## 2.3. Sampling Method and Data Collection

Before data collection began in each sampling unit, farmers were given a briefing on the study’s goals and engaged in a random, open-ended discussion. Observations and measurements made on the ground as well as secondary sources were used to gather the data. Blackhead Somali sheep organized farm and the sheep farmers rearing Blackhead Somali sheep were purposively selected. Only those sheep were chosen from among sheep farmers whose record of age was kept by the farmers. For morphometric characterization, 460 sheep of both sexes were used; however, the reproductive performance of 110 male and 150 female breeding sheep was determined.


### 2.3.1. Qualitative and Quantitative Data

Data on both qualitative and quantitative linear body measurements were gathered following the Food and Agriculture Organization’s suggested descriptor lists [11]. Since the animals’ posture, movements, and gut contents can affect body measurements, all the information was collected early in the morning. With just the naked eye, morphological characteristics such as coat type and pattern, head profile, ear orientation, wattle, horn, back and rump profile, and tail type were examined. Body measurements (in cm) such as body weight (BW), pelvic width (PW), heart girth (HG), body length (BL), height at rump (HR), height at wither (HW), tail circumference (TC), tail length (TL), scrotal circumference (SC), ear length (EL), and chest depth (CD) were measured using tailors measuring tape with records taken to the nearest cm after restraining and holding the animal in an unforced position. To reduce postprandial gastrointestinal fluctuation, body weight was recorded in the morning before the animals were released for eating. This was performed using a suspended spring balance with a 50 kg capacity and a 0.2 kg precision.The record was kept at the Blackhead Somali sheep organized farm and an interview with the farmers rearing Blackhead Somali sheep was used to gather data for characterizing reproduction qualities, which were then included in the datasheet. Data on reproductive features, including the age of the ram and ewe at first service, the age at first lambing, the interval between lambing, the ewe and ram’s reproductive life span, the longevity of the lamb crop, twinning and triplets, and mortality up to 90 days, were gathered.


## 2.3.1. Qualitative and Quantitative Data

Data on both qualitative and quantitative linear body measurements were gathered following the Food and Agriculture Organization’s suggested descriptor lists [11]. Since the animals’ posture, movements, and gut contents can affect body measurements, all the information was collected early in the morning. With just the naked eye, morphological characteristics such as coat type and pattern, head profile, ear orientation, wattle, horn, back and rump profile, and tail type were examined. Body measurements (in cm) such as body weight (BW), pelvic width (PW), heart girth (HG), body length (BL), height at rump (HR), height at wither (HW), tail circumference (TC), tail length (TL), scrotal circumference (SC), ear length (EL), and chest depth (CD) were measured using tailors measuring tape with records taken to the nearest cm after restraining and holding the animal in an unforced position. To reduce postprandial gastrointestinal fluctuation, body weight was recorded in the morning before the animals were released for eating. This was performed using a suspended spring balance with a 50 kg capacity and a 0.2 kg precision.The record was kept at the Blackhead Somali sheep organized farm and an interview with the farmers rearing Blackhead Somali sheep was used to gather data for characterizing reproduction qualities, which were then included in the datasheet. Data on reproductive features, including the age of the ram and ewe at first service, the age at first lambing, the interval between lambing, the ewe and ram’s reproductive life span, the longevity of the lamb crop, twinning and triplets, and mortality up to 90 days, were gathered.


## 2.4. Data Management and Statistical Analysis

The morphological and qualitative data were gathered and entered into the Microsoft Excel spreadsheet. Individual observation qualitative data were evaluated using SAS version 9.1.3’s frequency techniques (2008). Quantitative variables were analyzed using the SAS general linear model (GLM) technique. Body weight and a linear body measurement other than scrotum circumference were fitted as dependent variables, with sex and age groups fitted as fixed independent variables. When there was a significant difference (p<0.05), Tukey’s test was applied to separate the means.


## 3. Results

### 3.1. Qualitative Physical Characteristics

The physical body characteristics of Blackhead Somali sheep obtained in the present study are presented in Table1. As indicated in Figures 1 and 2, a flock of sheep with typical color characteristics. Most (overall 67.3%) of the Blackhead Somali sheep had plain coat color patterns (70.9% for males and 64.7% for females) followed by patchy (overall 19.2%) and spotted (overall 13.5%) coat color patterns. White body with blackhead was the dominant coat color (overall 86.2%) with 88.2% for males and 84.7% for females but white body and blackhead with a white dominant, black body and white body were also present in the study population (Table 1). The facial head profile was predominantly straight (overall 80.8%) followed by convex (overall 16.9%) and concave (overall 2.3%).Table 1
Qualitative physical body characteristics of Blackhead Somali sheep.
CharacterAttributeMale (%)Female (%)Overall (%)Coat color patternPlain78 (70.9)97 (64.7)175 (67.3)Patchy20 (18.2)30 (20.0)50 (19.2)Spotted12 (10.9)23 (15.3)35 (13.5)Total110 (100)150 (100)260 (100)Coat color typeWhite body with blackhead97 (88.2)127 (84.7)224 (86.2)White body and blackhead with white dominant8 (7.3)17 (11.3)25 (9.6)Black body4 (3.6)3 (2.0)7 (2.7)White body1 (0.9)3 (2.0)4 (1.5)Total110 (100)150 (100)260 (100)Facial (head) profileStraight87 (79.1)123 (82.0)210 (80.8)Concave19 (17.3)25 (16.7)44 (16.9)Convex4 (3.6)2 (1.3)6 (2.3)Total110 (100)150 (100)260 (100)DewlapPresent101 (91.8)139 (92.7)240 (93.3)Absent9 (8.2)11 (7.3)20 (7.7)Total110 (100)150 (100)260 (100)HornAbsent100 (90.9)148 (98.7)248 (95.4)Present10 (9.1)2 (1.3)12 (4.6)Total110 (100)150 (100)260 (100)Ear orientationHorizontal70 (63.6)104 (69.3)174 (66.9)Semi-pendulous25 (22.7)24 (16.0)49 (18.8)Pendulous8 (7.3)19 (12.7)27 (10.5)Erected7 (6.4)3 (2.0)10 (3.8)Total110 (100)150 (100)260 (100)Back profileSlopes up towards the rump52 (47.3)77 (51.3)129 (49.6)Straight43 (39.1)49 (32.7)92 (35.4)Slopes down from withers10 (9.1)24 (16.0)34 (13.1)Dipped/curved5 (4.5)0 (0.0)5 (1.9)Total110 (100)150 (100)260 (100)Rump profileSloppy86 (78.2)124 (82.7)210 (80.8)Flat20 (18.2)16 (10.7)36 (13.8)Roofy4 (3.6)10 (6.7)14 (5.4)Total110 (100)150 (100)260 (100)Figure 1
Flock of Blackhead Somali sheep (blackhead with a white body).Figure 2
Straight head profile, well-developed dewlap, and absence of horn in Blackhead Somali sheep.Wattle is absent, although dewlap, a skin extension, was found in 93.3% under study (91.8% of males and 92.7% of females). The majority of the ears were horizontal (overall 66.9 percent) and 95.4% of the population lacked a horn (90.9 percent in males and 98.7 percent in females). The majority of sheep have a sloping back profile (total 49.6%), which is followed by a straight rump (overall 35.4 percent). The majority of sheep have sloppy rumps (80.8 percent overall), then flat rumps (overall 13.8 percent).


### 3.2. Morphometric Characteristics

#### 3.2.1. Body Weight

The overall average body weight of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 2.14 ± 0.30 kg, 6.37 ± 0.92 kg, 11.05 ± 1.38 kg, 14.25 ± 1.50 kg, 17.75 ± 1.53 kg, 22.37 ± 2.28 kg, and 30.00 ± 5.39 kg respectively (Table2). There was no significant (p>0.05) difference in the body weight of male and female sheep at birth and up to nine months of age while it differs significantly (p<0.05) at 1 and 2 years of age.Table 2
Common morphometric characters of Blackhead Somali males and females sheep.
ParametersAt birth1 month3 months6 monthsMaleFemaleOverallMaleFemaleOverallMaleFemaleOverallMaleFemaleOverallBody weight (kg)2.05 ± 0.242.22 ± 0.332.14 ± 0.306.50 ± 0.946.23 ± 0.896.37 ± 0.9210.73 ± 1.3111.37 ± 1.4011.05 ± 1.3814.13 ± 1.4714.37 ± 1.5414.25 ± 1.50Body length (cm)25.80 ± 1.8825.13 ± 2.6425.46 ± 2.2932.60 ± 3.1634.00 ± 2.0333.30 ± 2.7239.37 ± 2.4738.40 ± 1.8338.88 ± 2.2142.23 ± 7.8444.23 ± 2.3943.23 ± 5.84Height at withers (cm)29.10 ± 2.6428.93 ± 2.4429.02 ± 2.5338.80 ± 5.0637.87 ± 1.9838.33 ± 3.8345.57 ± 3.7945.10 ± 2.5945.33 ± 3.2252.66 ± 2.0351.83 ± 1.8252.25 ± 1.96Height at rump (cm)28.87 ± 2.2429.10 ± 2.3828.98 ± 2.2941.73 ± 4.7139.43 ± 1.6940.58 ± 3.6945.87 ± 3.5646.17 ± 2.1246.02 ± 2.9153.03 ± 2.0651.93 ± 2.1952.48 ± 2.18Heart girth (cm)29.47 ± 3.0128.97 ± 2.9229.21 ± 2.9541.20 ± 3.3439.43 ± 2.5240.31 ± 3.0749.03a ± 2.3245.57b ± 2.7547.30 ± 3.0754.30 ± 2.3253.43 ± 2.1953.87 ± 2.28Chest depth (cm)9.97 ± 1.869.80 ± 1.309.88 ± 2.5018.57 ± 2.4017.53 ± 1.8018.05 ± 2.1718.27 ± 1.9117.10 ± 1.8817.68 ± 1.9723.07 ± 1.9121.30 ± 1.5322.18 ± 1.93Pelvic width (cm)8.07 ± 1.548.33 ± 1.368.20 ± 1.459.17a ± 0.9511.23a ± 0.9710.20 ± 1.419.83a ± 1.2312.43b ± 0.9711.13 ± 1.7111.53a ± 1.7914.40b ± 1.2212.97 ± 2.09Ear length (cm)5.77 ± 1.106.33 ± 1.066.05 ± 1.117.56 ± 1.167.80 ± 1.197.68 ± 1.179.20 ± 1.568.93 ± 1.349.07 ± 1.459.10 ± 1.478.76 ± 1.618.93 ± 1.54Tail circumference (cm)13.50 ± 1.1412.80 ± 1.1713.15 ± 1.8217.80 ± 1.4517.86 ± 1.7117.83 ± 2.0530.15 ± 2.5529.65 ± 3.1629.90 ± 3.7838.30 ± 3.3537.66 ± 3.1937.98 ± 3.75Tail length (cm)5.87 ± 0.975.57 ± 0.775.71 ± 0.887.67 ± 1.067.73 ± 1.287.70 ± 1.178.60 ± 0.978.03 ± 1.128.31 ± 1.0810.10 ± 2.058.87 ± 1.769.48 ± 2.09Scrotal circumference (cm)5.20 ± 0.80—5.20 ± 0.806.80 ± 0.66—6.80 ± 0.6611.10 ± 1.78—11.10 ± 1.7813.33 ± 2.56—13.33 ± 2.56Parameters9 months1 year2 yearsMaleFemaleOverallMaleFemaleOverallMaleFemaleOverallBody weight (kg)18.33 ± 1.3717.17 ± 1.4917.75 ± 1.5323.40a ± 2.0221.33b ± 2.0722.37 ± 2.2833.78a ± 3.0726.22b ± 3.0730.00 ± 5.39Body length (cm)48.77 ± 2.7147.13 ± 2.5447.95 ± 2.7353.97 ± 2.2952.40 ± 1.9453.18 ± 2.2562.16a ± 3.4056.20b ± 2.9359.18 ± 4.35Height at withers (cm)57.70 ± 2.6355.13 ± 2.1055.41 ± 2.3861.67 ± 2.0960.57 ± 2.2261.11 ± 2.2170.64a ± 5.4065.60b ± 3.5668.12 ± 5.21Height at rump (cm)55.57 ± 2.5356.47 ± 2.1456.02 ± 2.3662.27 ± 2.6361.50 ± 2.5261.88 ± 2.5971.90a ± 6.4667.76b ± 3.1169.83 ± 5.46Heart girth (cm)59.23 ± 2.8857.23 ± 2.1658.23 ± 2.7262.50 ± 2.6661.13 ± 2.2261.81 ± 2.5275.92a ± 5.0570.38b ± 2.6073.15 ± 4.87Chest depth (cm)25.07 ± 1.4323.63 ± 1.6524.35 ± 1.6930.90 ± 2.1828.40 ± 2.2629.65 ± 2.5434.58a ± 3.2231.16b ± 2.8832.87 ± 3.49Pelvic width (cm)13.53a ± 1.4815.60b ± 1.5414.56 ± 1.8214.97a ± 1.4016.70b ± 1.5715.83 ± 1.7117.52a ± 2.1219.80b ± 1.9018.66 ± 2.01Ear length (cm)9.97 ± 1.4010.00 ± 1.419.98 ± 1.3910.33 ± 1.2410.10 ± 1.8010.21 ± 1.5411.06 ± 1.7510.80 ± 1.6510.93 ± 1.70Tail circumference (cm)49.48 ± 2.3547.96 ± 3.5548.72 ± 3.0255.75a ± 4.7051.85b ± 5.6353.80 ± 6.3261.44a ± 6.0057.60b ± 4.2259.62 ± 5.36Tail length (cm)11.20 ± 1.2110.67 ± 1.5610.93 ± 1.4112.63 ± 1.4212.80 ± 1.3712.71 ± 1.3913.26 ± 1.6413.22 ± 1.3513.24 ± 1.49Scrotal circumference (cm)16.77 ± 1.92—16.77 ± 1.9218.50 ± 1.75—18.50 ± 1.7522.00 ± 2.83—22.00 ± 2.83


#### 3.2.2. Body Length

The overall average body length of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 25.46 ± 2.29 cm, 33.30 ± 2.72 cm, 38.88 ± 2.21 cm, 43.23 ± 5.84 cm, 47.95 ± 2.73 cm, 53.18 ± 2.25 cm, and 59.18 ± 4.35 cm, respectively (Table2). There was no significant (p>0.05) difference in the body length of male and female sheep up to 12 months of age while it differs significantly (p<0.05) at 2 years of age.


#### 3.2.3. Height at Wither

The overall average height at withers of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age was found to be 29.02 ± 2.53 cm, 38.33 ± 3.83 cm, 45.33 ± 3.22 cm, 52.25 ± 1.96 cm, 55.41 ± 2.38 cm, 61.11 ± 2.21 cm, and 68.12 ± 5.21 cm, respectively (Table2). The average height at wither of male and female sheep differs significantly (p<0.05) at 2 years of age. The average height at wither of males was higher than female sheep.


#### 3.2.4. Height at Rump

The overall average height at the rump of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 28.98 ± 2.29 cm, 40.58 ± 3.69 cm, 46.02 ± 2.91 cm, 52.48 ± 2.18 cm, 56.02 ± 2.36 cm, 61.88 ± 2.59 cm, and 69.83 ± 5.46 cm respectively (Table2). The average height at the rump of male and female sheep differs significantly (p<0.05) at 2 years of age.


#### 3.2.5. Heart Girth

The overall average heart girth of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 29.21 ± 2.95 cm, 40.31 ± 3.07 cm, 47.30 ± 3.07 cm, 53.87 ± 2.28 cm, 58.23 ± 2.72 cm, 61.81 ± 2.52 cm, and 73.15 ± 4.87 cm, respectively (Table2). Average heart girth differs significantly (p<0.05) among male and female sheep after the 3rd month and 2 years of age. The average heart girth of males was higher than that of female sheep.


#### 3.2.6. Chest Depth

The overall average chest depth of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 9.88 ± 2.50 cm, 18.05 ± 2.17 cm, 17.68 ± 1.97 cm, 22.18 ± 1.93 cm, 24.35 ± 1.69 cm, 29.65 ± 2.54 cm, and 32.87 ± 3.49 cm, respectively (Table2). The chest depth of Blackhead Somali sheep of male and female sheep differs significantly (p<0.05) at 2 years of age and it was higher in males than that in female sheep.


#### 3.2.7. Pelvic Width

The overall average pelvic width of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 8.20 ± 1.45 cm, 10.20 ± 1.41 cm, 11.13 ± 1.71 cm, 12.97 ± 2.09 cm, 14.56 ± 1.82 cm, 15.83 ± 1.71 cm, and 18.66 ± 2.01 cm, respectively (Table2). Significant (p<0.05) difference in average pelvic width of male and female sheep was observed after 3rd month of age onwards and females had broader pelvic width than male sheep.


#### 3.2.8. Ear Length

The overall average ear length of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 6.05 ± 1.11 cm, 7.68 ± 1.17 cm, 9.07 ± 1.45 cm, 8.93 ± 1.54 cm, 9.98 ± 1.39 cm, 10.21 ± 1.54 cm, and 10.93 ± 1.70 cm, respectively (Table2). There was no significant (p>0.05) difference in the average ear length of male and female sheep.


#### 3.2.9. Tail Circumference

The overall average tail circumference at the base of the tail of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 13.15 ± 1.82 cm, 17.83 ± 2.05 cm, 29.90 ± 3.78 cm, 37.98 ± 3.75 cm, 48.72 ± 3.02 cm, 53.80 ± 6.32 cm, and 59.62 ± 5.36 cm, respectively (Table2). Significant (p<0.05) difference in average tail circumference of male and female sheep was observed after one year of age onwards and the male had a larger tail circumference than the female sheep.


#### 3.2.10. Scrotal Circumference

The overall average scrotal circumference of male Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 5.20 ± 0.80 cm, 6.80 ± 0.66 cm, 11.10 ± 1.78 cm, 13.33 ± 2.56 cm, 16.77 ± 1.92 cm, 18.50 ± 1.75 cm, and 22.00 ± 2.83 cm, respectively (Table2).


### 3.3. Correlations between Linear Body Measurements in Blackhead Somali Sheep

The relationships of linear body measurements in Blackhead Somali sheep are presented in Table3. All the linear body measurements had a significant positive correlation (p<0.01) with each other.Table 3
Correlations between linear body measurements in Blackhead Somali sheep.
Body weightHeart girthBody lengthHeight at rumpHeight at witherPelvic widthChest depthTail circumferenceTail lengthEar lengthScrotal circumferenceBody weight10.968∗∗0.961∗∗0.951∗∗0.953∗∗0.861∗∗0.930∗∗0.531∗∗0.823∗∗0.672∗∗0.941∗∗Heart girth0.968∗∗10.958∗∗0.970∗∗0.972∗∗0.859∗∗0.945∗∗0.530∗∗0.844∗∗0.705∗∗0.939∗∗Body length0.961∗∗0.958∗∗10.943∗∗0.948∗∗0.856∗∗0.928∗∗0.513∗∗0.830∗∗0.684∗∗0.913∗∗Height at rump0.951∗∗0.970∗∗0.943∗∗10.989∗∗0.855∗∗0.950∗∗0.511∗∗0.842∗∗0.700∗∗0.920∗∗Height at wither0.953∗∗0.972∗∗0.948∗∗0.989∗∗10.851∗∗0.945∗∗0.506∗∗0.839∗∗0.705∗∗0.924∗∗Pelvic width0.861∗∗0.859∗∗0.856∗∗0.855∗∗0.851∗∗10.813∗∗0.451∗∗0.753∗∗0.620∗∗0.849∗∗Chest depth0.930∗∗0.945∗∗0.928∗∗0.950∗∗0.945∗∗0.813∗∗10.494∗∗0.830∗∗0.676∗∗0.895∗∗Tail circumference0.531∗∗0.530∗∗0.513∗∗0.511∗∗0.506∗∗0.451∗∗0.494∗∗10.399∗∗0.360∗∗0.515∗∗Tail length0.823∗∗0.844∗∗0.830∗∗0.842∗∗0.839∗∗0.753∗∗0.830∗∗0.399∗∗10.635∗∗0.851∗∗Ear length0.672∗∗0.705∗∗0.684∗∗0.700∗∗0.705∗∗0.620∗∗0.676∗∗0.360∗∗0.635∗∗10.683∗∗Scrotal circumference0.941∗∗0.939∗∗0.913∗∗0.920∗∗0.924∗∗0.849∗∗0.895∗∗0.515∗∗0.851∗∗0.683∗∗1∗∗ correlation is significant at the 0.01 level.


### 3.4. Reproductive Performance

The average age of the first service in ram was recorded to be 10.08 ± 1.90 months. The average age at first service, age at first lambing, lambing interval, and life lamb crop in ewe were recorded to be 13.75 ± 2.44 months, 19.12 ± 2.41 months, 9.66 ± 1.56 months, and 6.18 ± 2.01 months, respectively. The average reproductive life span of ewe and ram was recorded to be 6.04 ± 1.43 years and 6.63 ± 1.49 years, respectively. The twinning and triplet rate were recorded to be 12.30% and 1.90%, respectively (Table4). Sheep mortality during the last 12 months was assessed based on the recall of sheep owners. The mortality in lambs below 3 months of age was recorded to be 10.40%.Table 4
Reproductive performance of Blackhead Somali sheep.
ParametersNMean ± SDAge of first service ram (months)11010.08 ± 1.90Age of first service ewe (months)15013.75 ± 2.44Age of first lambing (months)11019.12 ± 2.41Lambing interval (months)1109.66 ± 1.56Life lamb crop1066.18 ± 2.01The reproductive life span of ewe (years)1066.04 ± 1.43The reproductive life span of ram (years)1016.63 ± 1.49Twinning percentage (%)15012.30Triplet percentage (%)1501.90Mortality rates up to 90 days after birth (%)15010.40


## 3.1. Qualitative Physical Characteristics

The physical body characteristics of Blackhead Somali sheep obtained in the present study are presented in Table1. As indicated in Figures 1 and 2, a flock of sheep with typical color characteristics. Most (overall 67.3%) of the Blackhead Somali sheep had plain coat color patterns (70.9% for males and 64.7% for females) followed by patchy (overall 19.2%) and spotted (overall 13.5%) coat color patterns. White body with blackhead was the dominant coat color (overall 86.2%) with 88.2% for males and 84.7% for females but white body and blackhead with a white dominant, black body and white body were also present in the study population (Table 1). The facial head profile was predominantly straight (overall 80.8%) followed by convex (overall 16.9%) and concave (overall 2.3%).Table 1
Qualitative physical body characteristics of Blackhead Somali sheep.
CharacterAttributeMale (%)Female (%)Overall (%)Coat color patternPlain78 (70.9)97 (64.7)175 (67.3)Patchy20 (18.2)30 (20.0)50 (19.2)Spotted12 (10.9)23 (15.3)35 (13.5)Total110 (100)150 (100)260 (100)Coat color typeWhite body with blackhead97 (88.2)127 (84.7)224 (86.2)White body and blackhead with white dominant8 (7.3)17 (11.3)25 (9.6)Black body4 (3.6)3 (2.0)7 (2.7)White body1 (0.9)3 (2.0)4 (1.5)Total110 (100)150 (100)260 (100)Facial (head) profileStraight87 (79.1)123 (82.0)210 (80.8)Concave19 (17.3)25 (16.7)44 (16.9)Convex4 (3.6)2 (1.3)6 (2.3)Total110 (100)150 (100)260 (100)DewlapPresent101 (91.8)139 (92.7)240 (93.3)Absent9 (8.2)11 (7.3)20 (7.7)Total110 (100)150 (100)260 (100)HornAbsent100 (90.9)148 (98.7)248 (95.4)Present10 (9.1)2 (1.3)12 (4.6)Total110 (100)150 (100)260 (100)Ear orientationHorizontal70 (63.6)104 (69.3)174 (66.9)Semi-pendulous25 (22.7)24 (16.0)49 (18.8)Pendulous8 (7.3)19 (12.7)27 (10.5)Erected7 (6.4)3 (2.0)10 (3.8)Total110 (100)150 (100)260 (100)Back profileSlopes up towards the rump52 (47.3)77 (51.3)129 (49.6)Straight43 (39.1)49 (32.7)92 (35.4)Slopes down from withers10 (9.1)24 (16.0)34 (13.1)Dipped/curved5 (4.5)0 (0.0)5 (1.9)Total110 (100)150 (100)260 (100)Rump profileSloppy86 (78.2)124 (82.7)210 (80.8)Flat20 (18.2)16 (10.7)36 (13.8)Roofy4 (3.6)10 (6.7)14 (5.4)Total110 (100)150 (100)260 (100)Figure 1
Flock of Blackhead Somali sheep (blackhead with a white body).Figure 2
Straight head profile, well-developed dewlap, and absence of horn in Blackhead Somali sheep.Wattle is absent, although dewlap, a skin extension, was found in 93.3% under study (91.8% of males and 92.7% of females). The majority of the ears were horizontal (overall 66.9 percent) and 95.4% of the population lacked a horn (90.9 percent in males and 98.7 percent in females). The majority of sheep have a sloping back profile (total 49.6%), which is followed by a straight rump (overall 35.4 percent). The majority of sheep have sloppy rumps (80.8 percent overall), then flat rumps (overall 13.8 percent).


## 3.2. Morphometric Characteristics

### 3.2.1. Body Weight

The overall average body weight of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 2.14 ± 0.30 kg, 6.37 ± 0.92 kg, 11.05 ± 1.38 kg, 14.25 ± 1.50 kg, 17.75 ± 1.53 kg, 22.37 ± 2.28 kg, and 30.00 ± 5.39 kg respectively (Table2). There was no significant (p>0.05) difference in the body weight of male and female sheep at birth and up to nine months of age while it differs significantly (p<0.05) at 1 and 2 years of age.Table 2
Common morphometric characters of Blackhead Somali males and females sheep.
ParametersAt birth1 month3 months6 monthsMaleFemaleOverallMaleFemaleOverallMaleFemaleOverallMaleFemaleOverallBody weight (kg)2.05 ± 0.242.22 ± 0.332.14 ± 0.306.50 ± 0.946.23 ± 0.896.37 ± 0.9210.73 ± 1.3111.37 ± 1.4011.05 ± 1.3814.13 ± 1.4714.37 ± 1.5414.25 ± 1.50Body length (cm)25.80 ± 1.8825.13 ± 2.6425.46 ± 2.2932.60 ± 3.1634.00 ± 2.0333.30 ± 2.7239.37 ± 2.4738.40 ± 1.8338.88 ± 2.2142.23 ± 7.8444.23 ± 2.3943.23 ± 5.84Height at withers (cm)29.10 ± 2.6428.93 ± 2.4429.02 ± 2.5338.80 ± 5.0637.87 ± 1.9838.33 ± 3.8345.57 ± 3.7945.10 ± 2.5945.33 ± 3.2252.66 ± 2.0351.83 ± 1.8252.25 ± 1.96Height at rump (cm)28.87 ± 2.2429.10 ± 2.3828.98 ± 2.2941.73 ± 4.7139.43 ± 1.6940.58 ± 3.6945.87 ± 3.5646.17 ± 2.1246.02 ± 2.9153.03 ± 2.0651.93 ± 2.1952.48 ± 2.18Heart girth (cm)29.47 ± 3.0128.97 ± 2.9229.21 ± 2.9541.20 ± 3.3439.43 ± 2.5240.31 ± 3.0749.03a ± 2.3245.57b ± 2.7547.30 ± 3.0754.30 ± 2.3253.43 ± 2.1953.87 ± 2.28Chest depth (cm)9.97 ± 1.869.80 ± 1.309.88 ± 2.5018.57 ± 2.4017.53 ± 1.8018.05 ± 2.1718.27 ± 1.9117.10 ± 1.8817.68 ± 1.9723.07 ± 1.9121.30 ± 1.5322.18 ± 1.93Pelvic width (cm)8.07 ± 1.548.33 ± 1.368.20 ± 1.459.17a ± 0.9511.23a ± 0.9710.20 ± 1.419.83a ± 1.2312.43b ± 0.9711.13 ± 1.7111.53a ± 1.7914.40b ± 1.2212.97 ± 2.09Ear length (cm)5.77 ± 1.106.33 ± 1.066.05 ± 1.117.56 ± 1.167.80 ± 1.197.68 ± 1.179.20 ± 1.568.93 ± 1.349.07 ± 1.459.10 ± 1.478.76 ± 1.618.93 ± 1.54Tail circumference (cm)13.50 ± 1.1412.80 ± 1.1713.15 ± 1.8217.80 ± 1.4517.86 ± 1.7117.83 ± 2.0530.15 ± 2.5529.65 ± 3.1629.90 ± 3.7838.30 ± 3.3537.66 ± 3.1937.98 ± 3.75Tail length (cm)5.87 ± 0.975.57 ± 0.775.71 ± 0.887.67 ± 1.067.73 ± 1.287.70 ± 1.178.60 ± 0.978.03 ± 1.128.31 ± 1.0810.10 ± 2.058.87 ± 1.769.48 ± 2.09Scrotal circumference (cm)5.20 ± 0.80—5.20 ± 0.806.80 ± 0.66—6.80 ± 0.6611.10 ± 1.78—11.10 ± 1.7813.33 ± 2.56—13.33 ± 2.56Parameters9 months1 year2 yearsMaleFemaleOverallMaleFemaleOverallMaleFemaleOverallBody weight (kg)18.33 ± 1.3717.17 ± 1.4917.75 ± 1.5323.40a ± 2.0221.33b ± 2.0722.37 ± 2.2833.78a ± 3.0726.22b ± 3.0730.00 ± 5.39Body length (cm)48.77 ± 2.7147.13 ± 2.5447.95 ± 2.7353.97 ± 2.2952.40 ± 1.9453.18 ± 2.2562.16a ± 3.4056.20b ± 2.9359.18 ± 4.35Height at withers (cm)57.70 ± 2.6355.13 ± 2.1055.41 ± 2.3861.67 ± 2.0960.57 ± 2.2261.11 ± 2.2170.64a ± 5.4065.60b ± 3.5668.12 ± 5.21Height at rump (cm)55.57 ± 2.5356.47 ± 2.1456.02 ± 2.3662.27 ± 2.6361.50 ± 2.5261.88 ± 2.5971.90a ± 6.4667.76b ± 3.1169.83 ± 5.46Heart girth (cm)59.23 ± 2.8857.23 ± 2.1658.23 ± 2.7262.50 ± 2.6661.13 ± 2.2261.81 ± 2.5275.92a ± 5.0570.38b ± 2.6073.15 ± 4.87Chest depth (cm)25.07 ± 1.4323.63 ± 1.6524.35 ± 1.6930.90 ± 2.1828.40 ± 2.2629.65 ± 2.5434.58a ± 3.2231.16b ± 2.8832.87 ± 3.49Pelvic width (cm)13.53a ± 1.4815.60b ± 1.5414.56 ± 1.8214.97a ± 1.4016.70b ± 1.5715.83 ± 1.7117.52a ± 2.1219.80b ± 1.9018.66 ± 2.01Ear length (cm)9.97 ± 1.4010.00 ± 1.419.98 ± 1.3910.33 ± 1.2410.10 ± 1.8010.21 ± 1.5411.06 ± 1.7510.80 ± 1.6510.93 ± 1.70Tail circumference (cm)49.48 ± 2.3547.96 ± 3.5548.72 ± 3.0255.75a ± 4.7051.85b ± 5.6353.80 ± 6.3261.44a ± 6.0057.60b ± 4.2259.62 ± 5.36Tail length (cm)11.20 ± 1.2110.67 ± 1.5610.93 ± 1.4112.63 ± 1.4212.80 ± 1.3712.71 ± 1.3913.26 ± 1.6413.22 ± 1.3513.24 ± 1.49Scrotal circumference (cm)16.77 ± 1.92—16.77 ± 1.9218.50 ± 1.75—18.50 ± 1.7522.00 ± 2.83—22.00 ± 2.83


### 3.2.2. Body Length

The overall average body length of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 25.46 ± 2.29 cm, 33.30 ± 2.72 cm, 38.88 ± 2.21 cm, 43.23 ± 5.84 cm, 47.95 ± 2.73 cm, 53.18 ± 2.25 cm, and 59.18 ± 4.35 cm, respectively (Table2). There was no significant (p>0.05) difference in the body length of male and female sheep up to 12 months of age while it differs significantly (p<0.05) at 2 years of age.


### 3.2.3. Height at Wither

The overall average height at withers of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age was found to be 29.02 ± 2.53 cm, 38.33 ± 3.83 cm, 45.33 ± 3.22 cm, 52.25 ± 1.96 cm, 55.41 ± 2.38 cm, 61.11 ± 2.21 cm, and 68.12 ± 5.21 cm, respectively (Table2). The average height at wither of male and female sheep differs significantly (p<0.05) at 2 years of age. The average height at wither of males was higher than female sheep.


### 3.2.4. Height at Rump

The overall average height at the rump of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 28.98 ± 2.29 cm, 40.58 ± 3.69 cm, 46.02 ± 2.91 cm, 52.48 ± 2.18 cm, 56.02 ± 2.36 cm, 61.88 ± 2.59 cm, and 69.83 ± 5.46 cm respectively (Table2). The average height at the rump of male and female sheep differs significantly (p<0.05) at 2 years of age.


### 3.2.5. Heart Girth

The overall average heart girth of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 29.21 ± 2.95 cm, 40.31 ± 3.07 cm, 47.30 ± 3.07 cm, 53.87 ± 2.28 cm, 58.23 ± 2.72 cm, 61.81 ± 2.52 cm, and 73.15 ± 4.87 cm, respectively (Table2). Average heart girth differs significantly (p<0.05) among male and female sheep after the 3rd month and 2 years of age. The average heart girth of males was higher than that of female sheep.


### 3.2.6. Chest Depth

The overall average chest depth of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 9.88 ± 2.50 cm, 18.05 ± 2.17 cm, 17.68 ± 1.97 cm, 22.18 ± 1.93 cm, 24.35 ± 1.69 cm, 29.65 ± 2.54 cm, and 32.87 ± 3.49 cm, respectively (Table2). The chest depth of Blackhead Somali sheep of male and female sheep differs significantly (p<0.05) at 2 years of age and it was higher in males than that in female sheep.


### 3.2.7. Pelvic Width

The overall average pelvic width of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 8.20 ± 1.45 cm, 10.20 ± 1.41 cm, 11.13 ± 1.71 cm, 12.97 ± 2.09 cm, 14.56 ± 1.82 cm, 15.83 ± 1.71 cm, and 18.66 ± 2.01 cm, respectively (Table2). Significant (p<0.05) difference in average pelvic width of male and female sheep was observed after 3rd month of age onwards and females had broader pelvic width than male sheep.


### 3.2.8. Ear Length

The overall average ear length of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 6.05 ± 1.11 cm, 7.68 ± 1.17 cm, 9.07 ± 1.45 cm, 8.93 ± 1.54 cm, 9.98 ± 1.39 cm, 10.21 ± 1.54 cm, and 10.93 ± 1.70 cm, respectively (Table2). There was no significant (p>0.05) difference in the average ear length of male and female sheep.


### 3.2.9. Tail Circumference

The overall average tail circumference at the base of the tail of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 13.15 ± 1.82 cm, 17.83 ± 2.05 cm, 29.90 ± 3.78 cm, 37.98 ± 3.75 cm, 48.72 ± 3.02 cm, 53.80 ± 6.32 cm, and 59.62 ± 5.36 cm, respectively (Table2). Significant (p<0.05) difference in average tail circumference of male and female sheep was observed after one year of age onwards and the male had a larger tail circumference than the female sheep.


### 3.2.10. Scrotal Circumference

The overall average scrotal circumference of male Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 5.20 ± 0.80 cm, 6.80 ± 0.66 cm, 11.10 ± 1.78 cm, 13.33 ± 2.56 cm, 16.77 ± 1.92 cm, 18.50 ± 1.75 cm, and 22.00 ± 2.83 cm, respectively (Table2).


## 3.2.1. Body Weight

The overall average body weight of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 2.14 ± 0.30 kg, 6.37 ± 0.92 kg, 11.05 ± 1.38 kg, 14.25 ± 1.50 kg, 17.75 ± 1.53 kg, 22.37 ± 2.28 kg, and 30.00 ± 5.39 kg respectively (Table2). There was no significant (p>0.05) difference in the body weight of male and female sheep at birth and up to nine months of age while it differs significantly (p<0.05) at 1 and 2 years of age.Table 2
Common morphometric characters of Blackhead Somali males and females sheep.
ParametersAt birth1 month3 months6 monthsMaleFemaleOverallMaleFemaleOverallMaleFemaleOverallMaleFemaleOverallBody weight (kg)2.05 ± 0.242.22 ± 0.332.14 ± 0.306.50 ± 0.946.23 ± 0.896.37 ± 0.9210.73 ± 1.3111.37 ± 1.4011.05 ± 1.3814.13 ± 1.4714.37 ± 1.5414.25 ± 1.50Body length (cm)25.80 ± 1.8825.13 ± 2.6425.46 ± 2.2932.60 ± 3.1634.00 ± 2.0333.30 ± 2.7239.37 ± 2.4738.40 ± 1.8338.88 ± 2.2142.23 ± 7.8444.23 ± 2.3943.23 ± 5.84Height at withers (cm)29.10 ± 2.6428.93 ± 2.4429.02 ± 2.5338.80 ± 5.0637.87 ± 1.9838.33 ± 3.8345.57 ± 3.7945.10 ± 2.5945.33 ± 3.2252.66 ± 2.0351.83 ± 1.8252.25 ± 1.96Height at rump (cm)28.87 ± 2.2429.10 ± 2.3828.98 ± 2.2941.73 ± 4.7139.43 ± 1.6940.58 ± 3.6945.87 ± 3.5646.17 ± 2.1246.02 ± 2.9153.03 ± 2.0651.93 ± 2.1952.48 ± 2.18Heart girth (cm)29.47 ± 3.0128.97 ± 2.9229.21 ± 2.9541.20 ± 3.3439.43 ± 2.5240.31 ± 3.0749.03a ± 2.3245.57b ± 2.7547.30 ± 3.0754.30 ± 2.3253.43 ± 2.1953.87 ± 2.28Chest depth (cm)9.97 ± 1.869.80 ± 1.309.88 ± 2.5018.57 ± 2.4017.53 ± 1.8018.05 ± 2.1718.27 ± 1.9117.10 ± 1.8817.68 ± 1.9723.07 ± 1.9121.30 ± 1.5322.18 ± 1.93Pelvic width (cm)8.07 ± 1.548.33 ± 1.368.20 ± 1.459.17a ± 0.9511.23a ± 0.9710.20 ± 1.419.83a ± 1.2312.43b ± 0.9711.13 ± 1.7111.53a ± 1.7914.40b ± 1.2212.97 ± 2.09Ear length (cm)5.77 ± 1.106.33 ± 1.066.05 ± 1.117.56 ± 1.167.80 ± 1.197.68 ± 1.179.20 ± 1.568.93 ± 1.349.07 ± 1.459.10 ± 1.478.76 ± 1.618.93 ± 1.54Tail circumference (cm)13.50 ± 1.1412.80 ± 1.1713.15 ± 1.8217.80 ± 1.4517.86 ± 1.7117.83 ± 2.0530.15 ± 2.5529.65 ± 3.1629.90 ± 3.7838.30 ± 3.3537.66 ± 3.1937.98 ± 3.75Tail length (cm)5.87 ± 0.975.57 ± 0.775.71 ± 0.887.67 ± 1.067.73 ± 1.287.70 ± 1.178.60 ± 0.978.03 ± 1.128.31 ± 1.0810.10 ± 2.058.87 ± 1.769.48 ± 2.09Scrotal circumference (cm)5.20 ± 0.80—5.20 ± 0.806.80 ± 0.66—6.80 ± 0.6611.10 ± 1.78—11.10 ± 1.7813.33 ± 2.56—13.33 ± 2.56Parameters9 months1 year2 yearsMaleFemaleOverallMaleFemaleOverallMaleFemaleOverallBody weight (kg)18.33 ± 1.3717.17 ± 1.4917.75 ± 1.5323.40a ± 2.0221.33b ± 2.0722.37 ± 2.2833.78a ± 3.0726.22b ± 3.0730.00 ± 5.39Body length (cm)48.77 ± 2.7147.13 ± 2.5447.95 ± 2.7353.97 ± 2.2952.40 ± 1.9453.18 ± 2.2562.16a ± 3.4056.20b ± 2.9359.18 ± 4.35Height at withers (cm)57.70 ± 2.6355.13 ± 2.1055.41 ± 2.3861.67 ± 2.0960.57 ± 2.2261.11 ± 2.2170.64a ± 5.4065.60b ± 3.5668.12 ± 5.21Height at rump (cm)55.57 ± 2.5356.47 ± 2.1456.02 ± 2.3662.27 ± 2.6361.50 ± 2.5261.88 ± 2.5971.90a ± 6.4667.76b ± 3.1169.83 ± 5.46Heart girth (cm)59.23 ± 2.8857.23 ± 2.1658.23 ± 2.7262.50 ± 2.6661.13 ± 2.2261.81 ± 2.5275.92a ± 5.0570.38b ± 2.6073.15 ± 4.87Chest depth (cm)25.07 ± 1.4323.63 ± 1.6524.35 ± 1.6930.90 ± 2.1828.40 ± 2.2629.65 ± 2.5434.58a ± 3.2231.16b ± 2.8832.87 ± 3.49Pelvic width (cm)13.53a ± 1.4815.60b ± 1.5414.56 ± 1.8214.97a ± 1.4016.70b ± 1.5715.83 ± 1.7117.52a ± 2.1219.80b ± 1.9018.66 ± 2.01Ear length (cm)9.97 ± 1.4010.00 ± 1.419.98 ± 1.3910.33 ± 1.2410.10 ± 1.8010.21 ± 1.5411.06 ± 1.7510.80 ± 1.6510.93 ± 1.70Tail circumference (cm)49.48 ± 2.3547.96 ± 3.5548.72 ± 3.0255.75a ± 4.7051.85b ± 5.6353.80 ± 6.3261.44a ± 6.0057.60b ± 4.2259.62 ± 5.36Tail length (cm)11.20 ± 1.2110.67 ± 1.5610.93 ± 1.4112.63 ± 1.4212.80 ± 1.3712.71 ± 1.3913.26 ± 1.6413.22 ± 1.3513.24 ± 1.49Scrotal circumference (cm)16.77 ± 1.92—16.77 ± 1.9218.50 ± 1.75—18.50 ± 1.7522.00 ± 2.83—22.00 ± 2.83


## 3.2.2. Body Length

The overall average body length of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 25.46 ± 2.29 cm, 33.30 ± 2.72 cm, 38.88 ± 2.21 cm, 43.23 ± 5.84 cm, 47.95 ± 2.73 cm, 53.18 ± 2.25 cm, and 59.18 ± 4.35 cm, respectively (Table2). There was no significant (p>0.05) difference in the body length of male and female sheep up to 12 months of age while it differs significantly (p<0.05) at 2 years of age.


## 3.2.3. Height at Wither

The overall average height at withers of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age was found to be 29.02 ± 2.53 cm, 38.33 ± 3.83 cm, 45.33 ± 3.22 cm, 52.25 ± 1.96 cm, 55.41 ± 2.38 cm, 61.11 ± 2.21 cm, and 68.12 ± 5.21 cm, respectively (Table2). The average height at wither of male and female sheep differs significantly (p<0.05) at 2 years of age. The average height at wither of males was higher than female sheep.


## 3.2.4. Height at Rump

The overall average height at the rump of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 28.98 ± 2.29 cm, 40.58 ± 3.69 cm, 46.02 ± 2.91 cm, 52.48 ± 2.18 cm, 56.02 ± 2.36 cm, 61.88 ± 2.59 cm, and 69.83 ± 5.46 cm respectively (Table2). The average height at the rump of male and female sheep differs significantly (p<0.05) at 2 years of age.


## 3.2.5. Heart Girth

The overall average heart girth of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 29.21 ± 2.95 cm, 40.31 ± 3.07 cm, 47.30 ± 3.07 cm, 53.87 ± 2.28 cm, 58.23 ± 2.72 cm, 61.81 ± 2.52 cm, and 73.15 ± 4.87 cm, respectively (Table2). Average heart girth differs significantly (p<0.05) among male and female sheep after the 3rd month and 2 years of age. The average heart girth of males was higher than that of female sheep.


## 3.2.6. Chest Depth

The overall average chest depth of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 9.88 ± 2.50 cm, 18.05 ± 2.17 cm, 17.68 ± 1.97 cm, 22.18 ± 1.93 cm, 24.35 ± 1.69 cm, 29.65 ± 2.54 cm, and 32.87 ± 3.49 cm, respectively (Table2). The chest depth of Blackhead Somali sheep of male and female sheep differs significantly (p<0.05) at 2 years of age and it was higher in males than that in female sheep.


## 3.2.7. Pelvic Width

The overall average pelvic width of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 8.20 ± 1.45 cm, 10.20 ± 1.41 cm, 11.13 ± 1.71 cm, 12.97 ± 2.09 cm, 14.56 ± 1.82 cm, 15.83 ± 1.71 cm, and 18.66 ± 2.01 cm, respectively (Table2). Significant (p<0.05) difference in average pelvic width of male and female sheep was observed after 3rd month of age onwards and females had broader pelvic width than male sheep.


## 3.2.8. Ear Length

The overall average ear length of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 6.05 ± 1.11 cm, 7.68 ± 1.17 cm, 9.07 ± 1.45 cm, 8.93 ± 1.54 cm, 9.98 ± 1.39 cm, 10.21 ± 1.54 cm, and 10.93 ± 1.70 cm, respectively (Table2). There was no significant (p>0.05) difference in the average ear length of male and female sheep.


## 3.2.9. Tail Circumference

The overall average tail circumference at the base of the tail of Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 13.15 ± 1.82 cm, 17.83 ± 2.05 cm, 29.90 ± 3.78 cm, 37.98 ± 3.75 cm, 48.72 ± 3.02 cm, 53.80 ± 6.32 cm, and 59.62 ± 5.36 cm, respectively (Table2). Significant (p<0.05) difference in average tail circumference of male and female sheep was observed after one year of age onwards and the male had a larger tail circumference than the female sheep.


## 3.2.10. Scrotal Circumference

The overall average scrotal circumference of male Blackhead Somali sheep at birth, 1, 3, 6, 9, 12, and 24 months of age were found to be 5.20 ± 0.80 cm, 6.80 ± 0.66 cm, 11.10 ± 1.78 cm, 13.33 ± 2.56 cm, 16.77 ± 1.92 cm, 18.50 ± 1.75 cm, and 22.00 ± 2.83 cm, respectively (Table2).


## 3.3. Correlations between Linear Body Measurements in Blackhead Somali Sheep

The relationships of linear body measurements in Blackhead Somali sheep are presented in Table3. All the linear body measurements had a significant positive correlation (p<0.01) with each other.Table 3
Correlations between linear body measurements in Blackhead Somali sheep.
Body weightHeart girthBody lengthHeight at rumpHeight at witherPelvic widthChest depthTail circumferenceTail lengthEar lengthScrotal circumferenceBody weight10.968∗∗0.961∗∗0.951∗∗0.953∗∗0.861∗∗0.930∗∗0.531∗∗0.823∗∗0.672∗∗0.941∗∗Heart girth0.968∗∗10.958∗∗0.970∗∗0.972∗∗0.859∗∗0.945∗∗0.530∗∗0.844∗∗0.705∗∗0.939∗∗Body length0.961∗∗0.958∗∗10.943∗∗0.948∗∗0.856∗∗0.928∗∗0.513∗∗0.830∗∗0.684∗∗0.913∗∗Height at rump0.951∗∗0.970∗∗0.943∗∗10.989∗∗0.855∗∗0.950∗∗0.511∗∗0.842∗∗0.700∗∗0.920∗∗Height at wither0.953∗∗0.972∗∗0.948∗∗0.989∗∗10.851∗∗0.945∗∗0.506∗∗0.839∗∗0.705∗∗0.924∗∗Pelvic width0.861∗∗0.859∗∗0.856∗∗0.855∗∗0.851∗∗10.813∗∗0.451∗∗0.753∗∗0.620∗∗0.849∗∗Chest depth0.930∗∗0.945∗∗0.928∗∗0.950∗∗0.945∗∗0.813∗∗10.494∗∗0.830∗∗0.676∗∗0.895∗∗Tail circumference0.531∗∗0.530∗∗0.513∗∗0.511∗∗0.506∗∗0.451∗∗0.494∗∗10.399∗∗0.360∗∗0.515∗∗Tail length0.823∗∗0.844∗∗0.830∗∗0.842∗∗0.839∗∗0.753∗∗0.830∗∗0.399∗∗10.635∗∗0.851∗∗Ear length0.672∗∗0.705∗∗0.684∗∗0.700∗∗0.705∗∗0.620∗∗0.676∗∗0.360∗∗0.635∗∗10.683∗∗Scrotal circumference0.941∗∗0.939∗∗0.913∗∗0.920∗∗0.924∗∗0.849∗∗0.895∗∗0.515∗∗0.851∗∗0.683∗∗1∗∗ correlation is significant at the 0.01 level.


## 3.4. Reproductive Performance

The average age of the first service in ram was recorded to be 10.08 ± 1.90 months. The average age at first service, age at first lambing, lambing interval, and life lamb crop in ewe were recorded to be 13.75 ± 2.44 months, 19.12 ± 2.41 months, 9.66 ± 1.56 months, and 6.18 ± 2.01 months, respectively. The average reproductive life span of ewe and ram was recorded to be 6.04 ± 1.43 years and 6.63 ± 1.49 years, respectively. The twinning and triplet rate were recorded to be 12.30% and 1.90%, respectively (Table4). Sheep mortality during the last 12 months was assessed based on the recall of sheep owners. The mortality in lambs below 3 months of age was recorded to be 10.40%.Table 4
Reproductive performance of Blackhead Somali sheep.
ParametersNMean ± SDAge of first service ram (months)11010.08 ± 1.90Age of first service ewe (months)15013.75 ± 2.44Age of first lambing (months)11019.12 ± 2.41Lambing interval (months)1109.66 ± 1.56Life lamb crop1066.18 ± 2.01The reproductive life span of ewe (years)1066.04 ± 1.43The reproductive life span of ram (years)1016.63 ± 1.49Twinning percentage (%)15012.30Triplet percentage (%)1501.90Mortality rates up to 90 days after birth (%)15010.40


## 4. Discussion

In this study, the Blackhead Somali sheep’s predominant coat color pattern was plain, but the group also included individuals with spotted and patchy color patterns. White body with blackhead is the predominant coat color type reported in Ethiopia’s Gode and Adadile districts, while the majority of Blackhead Somali sheep were also said to have a plain coat color pattern [12]. Gebremichael [3] also noted that the predominant coat color type is one with a white body and blackheads. Wendimu et al. [12] also observed a flat head shape, which is consistent with the present findings, however, Gebremichael [3] reported a convex head profile. Gebremichael, 2008 reported that wattle was absent and that the dewlap was well-developed, however, Wendimu et al. [12] reported that wattle was present in the majority of the population. In contrast to the findings of the present study, Gebremichael [3] reported the absence of a horn and an outwardly drooping, forward-facing ear. The discrepancy in results could be the result of selective breeding amongst Blackhead Somali sheep subtypes and races as well as environmental variations.The data on live body weight and linear measurements of the existing breeds are crucial for a successful selection procedure. After 1 year of age, there was a difference in body weight between male and female sheep that was significant (p<0.05). Other authors also found out that male Blackhead Somali sheep were heavier on average than females [12, 13]. Adult breeding female Blackhead Somali sheep were heavier than Afar and Menz sheep in comparison to local sheep breeds [14]. It was also noted that sex had a substantial impact on body weight in Mecheri sheep and Washera sheep, respectively, by Karunanithi et al. [15] and Mengiste et al. [16]. Mekuriaw et al. [17] revealed a nonsignificant effect of body weight on sex in adult Washer’s sheep, which is in contrast to the current findings. The current study’s findings on birth weight were consistent with the range of birth weights for Afar and Blackhead Somali sheep [18]. The body weight of Blackhead Somali rams and ewes was reported by Wendimu et al. [12] to be 28.3 kg and 26.7 kg, respectively, which is less than the current data. The main causes of the findings’ discrepancy are the management practices and lambing season [17, 19].Other morphometric measurements such as body length, heart girth, chest depth, height at the rump, height at withers, and tail circumference increased considerably (p<0.05) with age in males, in line with Blackhead’s observation. Somali Sheep in Ethiopia’s Gode and Adadile Districts; sheep breeds in Ethiopia’s Gamo Gofa Zone [20]; indigenous sheep type in Southern Ethiopia’s Bensa District [21]; Farta sheep in Ethiopia’s Amhara Region [22]; and Mecheri sheep in India [15]. The results of the present study, which are in agreement with those of Wendimu et al. [12] on Blackhead Somali sheep in the Gode and Adadile districts of Ethiopia, did not identify a significant (p>0.05) effect of sex on tail length. Abera Feyissa et al. [13] showed increased overall body weight, body length, and heart girth in female Blackhead Somali sheep in the Borana low terrain, southern Ethiopia, in contrast to the current findings. Due to geographical location, uncontrolled cross-breeding between subtypes and strains and genetic differences in sheep, these differences exist.Pelvic width was substantially greater in females, which is consistent with research on Blackhead Somali sheep in southern Ethiopia’s Borana lowlands [13]. Wendimu et al. [12] showed increased overall pelvic width in Blackhead Somali sheep in Gode and Adadile districts, Ethiopia, in contrast to current findings. Wendimu et al. [12] also reported a significant (p<0.05) variation in pelvic width between sexes. Indigenous sheep types in the Bensa District, Southern Ethiopia [21], Farta sheep in the Amhara region of Ethiopia [22], and sheep breeds in the Gamogofa zone of Ethiopia [21] all reported nonsignificant (p>0.05) effects of pelvic width between male and female sheep [11].Age and the location of an animal’s upbringing have an impact on the variation in morphometric measurements [7, 19, 23]. The nongenetic factors and geography account for the discrepancy between linear body measurement and body weight across individuals of the same sex with different agroecologies. According to Hoque et al. (2011), findings revealed that males’ and females’ ear lengths did not change significantly with age.According to Gebremichael [3] and Khan et al. [24], there is a strong link between linear body measurements and body weight, which suggests that body measurements may be utilized as a selection criterion for improving living weight [25–27]. The strongest link between body weight and heart circumference was also reported in Blackhead Somali sheep in the Gode and Adadile Districts of Ethiopia and the Borana low terrain in southern Ethiopia [12, 13]. The greater correlation between body weight and heart girth was caused by the heart girth’s comparatively big contribution to body weight, which is made up of bones, muscles, and viscera [28].In the present finding, the highest correlation of body weight with heart girth was in agreement with findings in Blackhead Somali sheep in Borana lowland, southern Ethiopia [13]; in Nilotic sheep [26]; in Yankasa sheep [25]; in Blackhead Somali sheep in Gode and Adadile Districts, Ethiopia [12]; in Yankasa ewes in the humid zone of Nigeria [27]; in local sheep in Ethiopia [3]; and Kanni Adu kids [28]. This would imply that heart girth is the best variable for predicting live weight than other linear body measurements.Although the association of scrotal circumference with body weight was influenced by breed, physiological status, diet, and management, there was a strong positive correlation between body weight and scrotal circumference in males (p<0.01) [29]. This result was consistent with earlier studies on the Bonga sheep breed [30]. According to the study’s extremely important finding that there is a relationship between body weight and scrotal circumference, selecting for scrotal circumference would produce individuals with a high sperm production capacity. Söderquist and Hultén [29] found that males with high scrotal circumference tend to have daughters who enter puberty earlier and produce more eggs each ovulatory cycle. Males’ scrotal size, semen characteristics, and desire all have a substantial correlation with age at first puberty [31]. The examination of breeding soundness must therefore include the measurement of scrotal circumference, and selection may be based on testicular circumference [31].The current findings revealed that the age at first service for ewe was higher than ram. Lower age at first service for ram and ewe than the current study was reported to be 5.12 ± 1.04 months and 6.35 ± 1.03 months for Begait ram and ewes in Ethiopia [32]; 7.51 ± 2.14 months and 7.1 ± 3 months in Bonga and Horro ram respectively and 9.3 ± 2.2 months and 7.8 ± 2.4 months in Bonga and Horro ewes respectively by Edea [30]; 6.35 ± 1.03 months for Begait ewe [32]. The age at first service in ewe in the current study was comparable with 10 months in traditional systems for Menz sheep [33]. The age of the first lambing and lambing interval in the current study was recorded to be 19.12 ± 2.41 months and 9.66 ± 1.56 months, respectively. The lower overall average age at first lambing in Begait sheep was reported to be11.34 ± 1.30 months [32]; 16.5 months in Menz sheep [34]; 14.9 ± 3.1 and 13.3 ± 1.7 months for Bonga and Horro sheep breeds respectively [30]; 470 ± 8.44 days under station management in Amhara region, Ethiopia [17]. The lower lambing interval in Begait sheep was reported to be 6.79 + 1.56 months [32]; 6.64 ± 1.13 months in Gumuz sheep [3]. However, it is shorter than 10.46 ± 2.58 months in Blackhead Somali sheep Ferew [35].The variation is due to breed and environmental differences. Contrary to the current finding, the lower lambing interval in ewe was reported to be 8.9 ± 2.1 months and 7.8 ± 2.4 months in Bonga and Horro ewes respectively [30]; 6.64 ± 1.13 months in Gumuz ewe [3]; 6.79 ± 1.55 months in Begait ewe [17] reported 263 and 303 days of lambing interval in Washera sheep under the station and on-farm management respectively which is comparable to the current finding. The traditional systems, where unregulated breeding is typical, typically have the shortest lambing intervals. Wilson and Durkin [36] discovered that long fat-tailed sheep stations managed in Rwanda had longer lambing intervals than the majority of intervals recorded from traditional African systems where controlled breeding was not performed. Therefore, the current feeding, housing, and breeding regime must be sufficient throughout the year to accomplish such optimal reproductive performances.The reproductive life span of ewe and ram in the current study were 6.04 ± 1.43 years and 6.63 ± 1.49 years, respectively. A higher average reproductive life span was reported in Begait sheep to be 7.71 ± 1.86 years [32], 7.9 ± 3.1 years, and 7.4 ± 2.7 years in Horro and Bonga ewes, respectively [30]. The long-term reproductive performance (long living, high fertility, and ability to produce more offspring) of dams should be given more importance in selection programs. The life lamb crop number in the current study was 6.18 ± 2.01 lambs which was less than 14.54 ± 3.53 lambs in Begait ewes [32]; 13.47 ± 1.76 lambs in Gumuz sheep in Metema areas (Gebremichael, 2007). Twinning and triplets percentage in the current study were less than 14.54 ± 3.53 lambs in Begait ewes [32] but it was in agreement with 13.47 ± 1.76 lambs in Gumuz sheep in Metema areas [3]. The higher mortality rate of lambs from birth to 3 months of age was reported to be 14% in Washera, Farta, and their crossbreed sheep under the farmers’ management system in the Western Highland of Amhara Region [17].


## 5. Conclusion

Blackhead Somali sheep is one of Ethiopia’s most common sheep breeds which has fatty tails and a straight, tapering finish. The body color of this breed is white, with blackheads predominating as the primary coat color, creating a basic color pattern. Compared to many other Ethiopian sheep breeds, an adult’s body size is big. Age and sex both have an impact on this breed’s body weight and other morphometric measures. The average age of the first service in ram was 10 months. In comparison to female sheep, male sheep are larger in terms of body weight, heart girth, length, height at the rump, and height at the withers. The most desirable traits which can also be employed as selection criteria include higher adult body weight, frequent twinning, and lower lamb mortality. The facial head profile was predominantly straight followed by convex and concave. The majority of sheep have a sloping back profile, which is followed by a straight rump. In conclusion, further genetic characterization and variation between and within these sheep types should be undertaken to increase the accuracy of phenotypic characterization and to develop an effective conservation and utilization program.



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*Source: 4865941-2022-10-27.xml*