Phenotypic characteristics of Algerian D'man sheep breed in Adrar oases

A Boubekeur, M T Benyoucef¹, M Lounassi, A Slimani and M Amiali¹

INRAA, experimental station, 01000 Adrar, Algeria
mt.benyoucef@ensa.dz
¹ National High School of Agronomy (ENSA) El-Harrach, Algiers 16000, Algeria

Abstract

In Algeria, D'man sheep breed is raised mainly in the Southwest oases (Gourara and Touat) especially in small family flocks and permanent housing. The  was carried out from the study of 354 animals over two sites: 271 heads in oases family farms and 83 heads in INRAA experimental station in the region of Adrar. 7 quantitative characters and 5 qualitative traits were recorded on 259 ewes and 95 rams.

The results show that the black color coat, alone or in combination with other colors is dominant. The absence of horns is a constant character in both sexes. 95.5% of the animals studied have a great white tip, and 78% of them have a white spot on the head. The variables tail length and ears length are low or have almost zero correlations with other variables. However, all other quantitative variables measured are correlated in both sexes. Sexual dimorphism (male versus female) of 1.07 was observed in the study. Males are 24% heavier than females. The coefficient of morphological features varied from 5.35% to 20%, showing therefore some heterogeneity. Differences (P <0.05) for several characters are found between flocks and between sexes. The results highlight the measured variables, differences in gender and age of the animals. Larger variability observed for coat color and live weight individual suggests opportunities for genetic improvement of the D’man breed by selection.

Keywords: morphological characterization, sexual dimorphism, system mixed

Introduction

In Algeria, the sheep number has increased from 17.5 to 26.6 million head with an average annual increase of 4.4% over the ten-year period (2003-2013) (MADR 2014). It is composed in majority by “hardy” breeds in different ecological zones: the Ouled Djellal breed (central-eastern of Algeria) is the dominant. It is followed successively by the Rembi and Hamra breeds (western of Algeria), Barbarine (South-eastern of Algeria) and D'man (South-West of Algeria).In Adrar region, during only 10 years, the number of sheep is increased from 339,200 to 451,000 heads (an average annual increase of about 3% over the same period). The flock size of the D'man breed is estimated at 10.1% in this region. It represents only 0.5% in the national flock (INRAA 2003). Then, this breed is classified among the endangered breeds which need to be studied and preserved.

All these sheep breeds are often exploited in livestock systems that can be mixed or specialized according to area and type of marketed animal product.

A production system can be considered as mixed by the joint production of milk and meat. It can also be by the presence beside a given species or breed other species and/or breeds used together.

Several studies on sheep reproduction and his management were conducted in Algeria (Abbas et al 2002; Dekhili 2002, 2004; Dekhili and Aggoun 2007). As for the works on phenotypic characterization of Algerian sheep, they are limited to breeds of the northern Algeria (Madani1987; Chellig 1986, 1992; ITELV 2001; Soltani 2011; Belaib and Dekhili 2012). However, the studies carried out on the phenotypic characterization of Algerian D’man breed in oases are few. On the other hand, this type of work had been realized on this breed in Morocco by Bouix and Kadiri (1975), Bouix et al (1977), Kerfal (2006) and by the Sheep and Goat Moroccan National Association in southeastern Morocco where D’man is described as the breed of oases.

Its breeding areas are located in the pre-Saharan regions of southern Maghreb, mainly oases of Errachidia, Ouarzazate, Dades and Draa (in southeastern Morocco), oases of Saoura, Touat and Gourara (in southwestern Algeria) and even Tozeur and Kebili in southern Tunisia (wikipedia.org).

All these studies reported that this breed has a high phenotypic heterogeneity with diversified pigmentation (white, black and brown colours and their combinations).

The present study aims to describe the phenotypic characteristics of the D'man breed in the Adrar oases where it seems well suited to the social context of the study area.

Materials and methods

In order to describe the animals sampled, a literature research was done to find the characteristics description of the D’man pure breed. Some works reported (Bouix and Kadiri, 1975; Bouix et al, 1977; Chellig 1992 and Khaldi et al, 2011) indicate that, morphologically, the D'man animals are lanky with a light frame, with a small, thin and long head and a weak skeleton. This breed presents a diverse pigmentation (many colors and color combinations) where the black is dominant.

In Algeria, D'man breed is located in the south-eastern oases (Saoura, Touat and Gourrara). The animals are raised in family small flocks (one ram and 3-4 ewes) and held in permanent housing inside the oases. This breed forms the basis of sedentary flocks feed mainly from the livestock farms.

The study was conducted in Adrar oases (southwestern Algeria), located in latitude 27° 49 N and longitude 00 11 E and an altitude of 279 m. The annual rainfall is negligible (less than 50 mm per year). They cannot be considered sufficient for the vegetation. The hot season is very long and extends from March to November.

Sample of animals

The studied animal samples are divided in two different livestock management (Table 1): a) The animals raised as family flocks in the oases of Adrar in traditional and rudimentary farming conditions represent 76.6% of the sample and consist of females (75.6%) and males (24.4%); b) A large flock raised in the experimental station of INRAA at Adrar where breeding management is favorable and allows animals to express better their performances. This flock consists of females (65.1%) and males (34.9%).

Variables analysis

The study focused on the analysis of quantitative (7) and qualitative (5) traits measured on each animal and registered in schedules.The 12 variables are indicated in Table 2.

Statistical analyzes were performed using SPSS and PASW20 softwares to estimate the descriptive elements of quantitative variables and frequencies for categorical variable sand the Pearson correlation coefficients between body measurements. A test of the two chi (X²) was applied to assess the effect of sex on the observed morphological characters.

The fixed effects including breeding conditions with two levels (Station, breeder), the animal sex with two levels (male, female) and the age of animals with three levels (2, 3 and 4 years)were estimated by analysis using the general linear model SPSS software.

Results and discussion

The qualitative characters of D’man breed

Three combinations types of two colors are seen in the studied animals: between black and white, black and brown and brown and white. A combination of three colors (black, white and brown) is reported in a little proportion of observed animals.

This study reveals a range of coat’s colors and a great morphological heterogeneity that could be explained by the combined effect of the introduction of other animals in the study area and its livestock management where the inbreeding phenomenon seems to appear atavistic character as reported by Bouix and Kadiri (1975).

The dominant color of the D’man coat is the black or combination color (black + other color). This result is similar to that reported by Khaldi et al (2011) in Tunisian oases. The great variability noted for the coat color of this breed shows possibilities for genetic improvement by selection.

The head shape is fine with an average length and a variety of colors. The presence of a white spot on the head is observed in very high proportion of the studied animals.

Males and females of the breed D'man do not present horns (Table 4). However, drafts were observed in males with 12.63% frequency. The absence of this trait in males D'man differentiates them from those of other local sheep breeds. This result confirms those reported by Bouix and Kadiri (1975) and Boujenane (1999) on the same breed in Morocco. This criterion is considered as a factor which differentiates D'man male from other local sheep breeds in Algeria.

The D'man breed is also distinguished by a thin and long tail of 42.9 cm on average with a white tip, which represents on average of 40% in its total length.

The pendants were not observed much in D'man animals. Pendants percentages for both sexes in females and males are lower than those obtained by Khaldi et al (2011), 41.3% and 16.3% respectively for males and females in sheep population.

The gender effect was highly significant on the animals coloring (Table 5). Different colors observed are well distributed among females D'man with close frequencies. Contrarily, in males, the black color dominates the other colors by 65.3%. The presence of pendants is high for females than for D'man males with a highly significant difference in this variable. Finally, the effect of gender does not appear to have a significant effect on other variables (Tall tip color, spot on head and horns).

The presence of the white tail tip for the majority of the animals was observed as indicated by Bouix and Kadiri (1975) for D'man in black coat animals.

The quantitative characters of the D'man breed

The average weight of D'man animals is distributed with heterogeneity (Table 6). This result is close to those observed by Bouix and Kadiri (1975) in the same breed (30 to 40 kg for ewe and 50 to 70 kg for rams).

The D'man animals observed in this study are lanky guy with a light frame and they are characterized by small size, a thin and long head and a weak skeleton.

Currently the D'man breed is localized mainly in the Southwest oasis of Touat, Tidikelt and Gourrara (Adrar region). His farming system is a family-led small herds (a ram with 2 or 3 ewes) held in permanent housing. Foods come from oases farms of the breeders and are often distributed in sufficient quantity. Flock reproduction management is made almost with the same animals and it suggests a high inbreeding because of the small size of family’s flocks (Boubekeur 2010).

The other variables (Wither height, body length, chest circumference, head length and ears length) indicate a little coefficient de variation.

Mostofthecriteriaweightandmorphologyexhibitstrongersignificantcorrelationcoefficient values in males than in females (Table 7). Indeed, the weight appears strongly correlated with the chest circumference. Similarly, the length of the head is correlated with the weight of the animal; but all of these correlation values are significant.

All combinations of correlation between variables (W, WH, BL, CC and HL) are positive and significant for both sexes. The length of the ear (EL) is well correlated significantly with the wither height (WH) in males D'man and moderately correlated with chest circumference (CC) in females. The length of the tail (TL) in male is highly correlated with WH, BL, CC and HL.

In females this variable is correlated with weight, WH and BL. The study reveals three negative correlations (one between EL and BL in males and the other two between the TL variable and HL and EL variables respectively).

A positive and high significant correlation was observed between body weight (BW) and the other measures of body (WH, BL, CC and TL) which can be considered as a possibility in the prediction of animal body weight (Salako 2006). Their selection into development programs can lead to an improvement of the format and the body condition of D'man animals.

In Algeria, the sheep are led in three main mixed farming systems: a) Pastoral extensive farming system in the steppe zone; b) The breeding farm system exists in some farms for meat production; c) The family breeding system where animals are held and led by the shepherd of the village in the north. However, in the Southwest oases, sheep (D'man and others) are associated with goats and operated continuously in small flocks in shelters for milk and meat (domestic consumption).

D'man breed tolerates the Saharan conditions and is characterized by exceptional performances (sexual precocity, ability to accelerated high prolificacy and lambing) as was reported by Boujenane (2003).This breed undergoes uncontrolled crossbreeding in its area of birth because of the introduction of local sheep breeds (Sidahou and white wool breeds) in oases and their excessive use in reproduction (Boubekeur 2010).

The results about the factors effects on the measured variables show in particular the importance of breeding conditions, animal’s age and sex (Table 8). Rearing conditions (experimental station or breeder) were highly significant on body weight (BW) and head length (HL). Moreover, the height at the withers (WH) and the chest circumference (CC) are also influenced by this factor. Similarly, a weak effect of this factor on body length was observed, while it seems to have no effect on the ear length (EL) and tail length (TL).

The effect of sex was observed highly significant on most of the analyzed variables (weight, WH, BL, CC, HL and TL) except for the length of the ears (EL).

The results indicate also that the D'man breed has a marked sexual dimorphism (sd). In fact, rams are larger than ewes for almost all criteria analyzed, except for the length of the ears (EL) for which the difference is not significant.

Sexual dimorphism appears as a fundamental component that affects the population dynamics, ecology, behavior and evolution (Esquivelzeta et al 2011).

The effect of the age of the animals is highly significant on the body length (BL), weight and the chest circumference. Older animals (3 and 4 years) are always large, heavy and longer compared to young animals (2 years). These results confirm those advanced by Khaldi et al (2011).

Furthermore, the effect of age has a significantly smaller effect on the head length (HL) and tail length and not significant on wither height (WH) and the length of the ears(EL).

Breeding conditions showed a highly significant effect on measurements. Animals raised in the experimental station are heavier and higher on legs than those of the oases farmers. Indeed, the flocks maintained in favorable breeding conditions expressed better their potential. However, the animals housed in shelters in oases are under less favorable growing conditions (insufficient and unbalanced feeding) which translate their low performances (Boubekeur 2010).

The mean values obtained for body weight, body length and chest circumference in D'man animals in the Adrar oases appears similar to those reported by Khaldi et al (2011) in the same breed in Tunisia (39.1 kg; 88,7cm and 81.7 cm for body weight, body length and chest circumference, respectively). While the average height at the withers obtained is higher than those reported by the same author (55.1 cm). Higher measures to those reported in this study for the same breed were also obtained by Rekik et al (2008) (WH 76 cm, CC 86.1 cm and 103.4 cm for BL).

Breeding type, food availability and the average age of the studied animal samples largely explain the differences obtained by studies on D’man breed reported by Boubekeur et al (2014).

Conclusion

• The study of quantitative and qualitative traits has contributed to describe the morphology of D'man animals exploited in the oases of the Adrar region. The body measurements indicated differences between males and females. The frequencies of coat colors are highly variable. The dominance of the black color in this breed either as a single color or in combination with other colors confirm results obtained by others authors.
  
  
• The D'man breed is distinguished by the absence of horns, a long white tail and the presence of white spot on the head. The pendants can also be observed.
  
  
• The phenotypic characteristics of D’man animals’ samples in Adrar oases seems similarly to that reported in the literature including Bouix et al (1975). Then, the diversity in colors and other morphological traits observed is confirmed. It suggests that the animal samples studied were subjected both to uncontrolled reproduction and exchanges among neighbouring countries along their borders.
  
  
• This work is a contribution to the knowledge of animal genetic resources in their environment. However, improvement’s reflections should cover also aspects related to the rational exploitation of flocks of the breed studied. The increase of its animal number remains the one of prerequisites for its development in its area of birth and rearing.

Acknowledgments

The authors thank the staff of the INRAA (headquarter in Algiers and Adrar station), the technical staff of Agricultural Services and sheep breeders surveyed in the Adrar region.

References

Abbas K, Chouya F and Madani T 2002: Reproductive improvement factors in sheep systems Algerian semiarid areas. Ruminants searches meetings, 9: 130 Consulted December 20, 2014, from http://www.journees3r.fr/IMG/pdf/2002_systemes_19_Abbas.pdf

Belaib L and Dekhili M 2012: Morphological characterization of sheep herds in the region of Setif (Algeria). Agriculture, 03: 1-9 Consulted December 09, 2014, from http://revue-agro.univ-setif.dz/documents/Issam-Dekhili.art1.pdf

Boubekeur A 2010: Testing of establishing typologies of dairy farming in the context of Southern Algeria: Case of Adrar. Magister thesis: Animal Science: Alger: National High School of Agronomy El-Harrach, 135 p

Boubekeur A, Benyoucef M T, Lounassi M and Slimani A 2014: Growth performance and sustainability of D'man lambs in INRAA Adrar station (southwest of Algeria). Ruminants searches meetings, 21: 270 Consulted February 10, 2015, from http://www.journees3r.fr/IMG/pdf/Texte_17_affiche_Genetique_A-Boubekeur.pdf

Boujenane I 1999:Genetic resources sheep in Morocco. Acts Press, Rabat, Morocco, 136 p.

Boujenane I 2003:Breeding sheep in Morocco: constraints and ways of improvement. Earth and life, 70: 1-7 Consulted November 11, 2014, from http://boujenane.com/phocadownload/AG_Ovine.pdf

Bouix J and Kadiri M 1975: One of major elements of the development of the palm: the D'man sheep breed. Mediterranean options, 26: 87-93 Consulted November 14, 2014, from http://om.ciheam.org/om/pdf/r26/CI010595.pdf

Bouix, J., Kadiri, M., Chari, A., Ghanime, R. and Rami, A. 1977 : Fiche signalétique de la race D'Man. Hommes, Terre et Eaux, 25: 9-11 from http://www.anafide.org/doc/HTE%2025/25-2.pdf

Chellig R 1986:The sheep breeds reared in Algeria. Agricultural Pedagogical National Center, Algiers, 50 p.

Chellig R 1992:The Algerian sheep breeds. Office of University Publications, Algiers, 80 p.

Dekhili M 2002: Reproductive Performance of simple and double born Ouled Djellal sheep. Meetings around the Research Ruminants, 9: 155 Consulted November 9, 2014, from http://www.journees3r.fr/IMG/pdf/2002_reproduction_08_Dekhili.pdf

Dekhili M 2004: Study of the productivity of a flock of Ouled Djellal. Ruminants searches meetings, 11: 234 Consulted November 9, 2014, from http://www.journees3r.fr/IMG/pdf/2004_itineraire_10_Dekhili.pdf

Dekhili M and Aggoun A 2007: Reproductive performance of ewes Ouled Djellal in two constraints of environment. Archivos de Zootecnia, 56 (216): 109-116 Consulted December 15, 2014, from http://www.uco.es/organiza/servicios/publica/az/php/img/web/06_17_39_20NotaPerformancesDekhili.pdf

Esquivelzeta C, Fina M, Bach R, Madruga C, Caja G, Casellas J and Piedrafita J 2011: Morphological analysis and subpopulation characterization of Ripollesa sheep breed. Animal Genetic Resources, 49: 9-17 Consulted October 21, 2014, from http://www.researchgate.net/profile/Gerardo_Caja2/publication/231975941_Morphological_analysis_and_subpopulation_characterization_of_ripollesa_sheep_breed/links/0c9605156c4a10d6af000000.pdf

INRAA (National Institute of Agronomic Research of Algeria, Algiers)2003: National Report on Animal Genetic Resources Algeria. 45 p.

ITLEV (Technical Institute of animal breeding), Algiers2001:Report on animal productions.10p.

Khaldi Z, Haddad B, Souid S, Rouissi H, Ben Gara A and Rekik B 2011: Phenotypical characterization of sheep population of the South-West of Tunisia. Animal Genetic Resources 49: 1-8 Consulted October 18, 2014, from http://www.fao.org/docrep/014/ba0128t/ba0128t00.pdf

Kerfal M 2006 : Performances zootechniques de la race ovine D’Man. Chapitre 16, in Boulanouar B et Paquay R 2006 : L’élevage du mouton et ses systèmes de production au Maroc. Rabat, INRA Maroc, 348 p. Consulted November 14, 2014, fromhttp://www.inra.org.ma/publications%5Couvrages%5Celevagemouton.pdf

Madani T 1987: Contribution to the knowledge of Algerian sheep breeds: Morphological study, reproductive traits and production. Thesis of engineer: National Agronomic Institute, Algiers. 95 p.

MADR (Ministry of Agriculture and Rural Development) 2014:Agricultural Statistics (areas and productions serie B,). Algiers.

Rekik B, Ben Gara A, Rouissi H, Barka F, Grami A and Khaldi Z 2008: Growth performance of lambs of D'man breed in the Tunisian oasis. Livestock Research for Rural Development, vol 20 and article n ° 162 Consulted November 18, 2014, fromhttp://www.lrrd.org/lrrd20/10/reki20162.htm

Salako A E 2006: Principal component factor analysis of the morph structure of immature Uda sheep. International Journal of Morphology, 24 (4): 571-574.

Soltani N 2011: Study of morphological characteristics of sheep in the region of Tebessa. Magistere memory. Ferhat Abbas University, Setif, 90 p.

Wikipedia.org: D’man. from http://fr.wikipedia.org/wiki/d’man#cite_note-RGO-1

Received 7 February 2015; Accepted 31 May 2015; Published 2 July 2015

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