INFLUENCE OF CAMEL BREEDS AND AGES ON THE REPRODUCTIVE PERFORMANCE OF DROMEDARY CAMELS IN SAUDI ARABIA

Influence of camel breeds and ages on the Reproductive performance of dromedary camels In saudi arabia

MOHAMMED, K.M.E.^* and AL-MUTAIRI, S.E.^**

^*Animal Reproduction Research Institute (ARRI), Giza, AL-Haram, Egypt, P.O. 12556

^** CamelResearchCenter, Sakaka/Al Jouf, Saudi Arabia, P.O.322

Correspondence email: kamel14@hotmail.com

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                                            ABSTRACT

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                                     Key words:Dromedary camels, reproductive performance, camel breeds.

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INTRODUCTION

The one-humped camel is a unique producer of food in the arid and semi-arid zones of the world. It is the only animal that can exist for several weeks without water and still able to provide its offspring and humans with milk (Yagil, 1982). The total population of camels in the world was estimated to be about 19 million, 14 million (73%) of which are in Africa and the Near East and 5 million (27%) in Asia (FAO 1992). The total population of dromedary is estimated to be around 1.6 million camels within the Arabian Peninsula, about 53% found in Saudi Arabia (FAO statistics, 2011). However, there is an important gap between the official number of camel heads according to FAO statistics (280,000 in 2009) and the national estimation published by the Ministry of Agriculture in Saudi Arabia (830,000 heads). Based on this last estimation, the camel population is 51% of the total tropical livestock in the country (Abdallah1 and Bernard Faye, 2012). The importance of camel in Saudi Arabia is clearly underlined by these data. Camels in Saudi Arabia play a major role in supplying the desert indwellers with milk and meat under extremely hostile conditions of temperature, drought and lack of pasture (Yagil and Etzion, 1980). Camel breeds derive their names from the areas of their habitats in dry and hot zones (North Africa, the North East and West Central Asia) as well as according to the tribe name (Wilson, 1984). A recent classification of camel breeds based on their economical traits was suggested by Wardeh (1989). Accordingly, Camels are assigned to four main classes: beef, dairy, dual purpose and racing camels. However, Saoud et al. (1988) and Basmaeil, et al. (2012) identified native camel breeds in the Saudi Arabia according to coat colors and production into Magahiem (black color, best milking breed); Maghatier (white color, moderate in milk production) Safrah (color mixture between the white and red) and Hamrah (color overlap between red and blond, more suitable for meat production than milk). The breeding of camels is at high risk because of the slow reproduction rate (Dahl and Hjort, 1979). Full reproductive capacity of the female camel reached at 6 years(Singh, 1966; Khetami, 1970), but it can be bred at 3-5 years of age (Matharu, 1966; Williamson and Payne, 1978). Yasin and Wahid (1957) reported that the female camel would breed until 30 years of age.

The production and reproduction in camels are affected by many factors such as late puberty, restricted breeding season, induced ovulation, long gestation period and long calving interval. These factors may constitute a major reason for the long generation interval in camels. The present investigation aimed to study the reproductive performance of Saudi Arabian camels under intensive management system will shed  more light on the influence of age and camel breeds on their reproductive performance traits.

MATERIALS and METHODS

The used records were collected from the farm of the camel station at the CamelResearchCenter at Sakaka, Al Jouf in the Northeastern part of Saudi Arabia. These records were used to evaluate the reproductive performance through measurement of the fertility parameters of Arabian camel under intensive controlled management. The reproductive parameters which tested in this study included, data of a total 197 female camel which collected from groups of sexually mature camels during consecutive breeding seasons over a period of 20 years (1985 to 2008). The animals were fed the available hay ad-libidum and 2-3 kg  concentrate pellets (containing 16% crude protein, 2.5-3.0% crude fat, 4.9-8.5% crude fiber, calcium 0.69-0.7%, phosphorus 0.4% and salt 1%). During breeding season variable amounts of alfalfa were offered to the animals. Supplementary feeding in the form of whole dates and bran were also offered irregularly.

The studied reproductive performance includes the following traits which described by EL-Azab et al. (1997): (1) Ages (months) and weights (kg) at first mating, first conception and first calving, (2) Interval between services (days) within the same breeding season which annually starts at early November to late April and may extended to early May, (3) Post-partum period (days); period between calving to onset of the first heat, (4) Service period (days); period extended from calving to successful conception within the same breeding season, (5) Open days period (days); elapsed from calving to last successful service which extended to forthcoming breeding season, (6) Number of services/conception, (7) Calving interval (days); period between two consecutive calving's.

The influence of camel breeds and ages on these traits were studied. Obtained data according to available observations of reproductive traits were tabulated into 2 fixed factors (camel breeds and ages) and statistically analyzed using the SPSS version 9 for Windows statistical software package. The data was also subjected to analysis of variance using General Linear Model (GLM) procedure and post Hoc multiple comparisons for observed means by Duncan's test for performances in relation to the suggested factors.

RESULTS

As shown in Tables 1 and 2, the overall mean values of ages at first mating, conception and calving were 39.75±0.61; 41.82±0.64 and 54.39±0.64 months, respectively. The overall means of the corresponding body weights were 437.17±6.75, 450.16±7.57 and 519.03±6.86 kg, respectively. The results indicated that, the differences between the camels' breeds (Magahiem, Maghatier, Hamrah and Safrah) were not significant for the studied ages and body weights at first services and conception. However, Safrah camel breed had lesser (P<0.05) body weight (499.00±14.04 Kg) at first calving than other camel breeds.

The overall mean values of the interval between services were 19.72±0.51, 19.13±0.42, 19.56±0.78 and 19.50±0.50 days for Magahiem, Maghatier, Safah and Hamrah camel breeds, respectively, whereas, the mean values of the same criteria for camel ages ≤5, 5-7, 7-9, 9-11 and ≥11 years were 19.28±0.32, 18.78±0.63, 20.41±0.84, 19.34±0.84 and 18.93±0.90 days, respectively (Table 3). Camel breeds and ages have a non-significant effect on this trait.

The effect of camel breeds and ages on post-partum period are illustrated in Table (4). Results indicated that, Hamrah camel breed had significant (P<0.05) shorter period (36.83±3.73 days) than other breeds. However, no significant effect to camel ages on the post-partum period, and the overall period was 45.39±2.57 days.

The influences of camel breeds and ages on the service periods are illustrated in Table (5). Results indicated that, Hamrah camel breed had significant (P<0.05) longer period (93.21±7.42 days) than other breeds, at the same time, female camel ages ≥11 years old had significant (P<0.05) longer period (90.88±10.85 days) than other studied ages.

The effects of camel breeds and ages on the open days period are showed in Table (6). The open days period were affected by camel breeds and ages, where, Maghatier camel breed recorded longer (P<0.05) period (329.51±7.50 days) than other breeds, and the camel ages 5-7 years reported longer (P<0.05) periods (342.46±7.59 days) than other studied ages. The influences of camel breeds and ages on the No. of service/conception are illustrated in Table (7). The overall mean value of number of services/conception was 2.57±0.02 services. Results indicated that, female camels ages had significant effect (P<0.05) on the number of service/conception and this indicated by medium ages (7 to 9 years) needs less services for conception (2.05±0.20), on the other hand younger (≤5 years) and older ages (≥11 years) needs more services for conception (2.88±0.17 and 2.81±0.27, respectively). However, the camel breeds had no significant effect on this trait.

Measurement of calving interval is an important as a herd performance monitoring tool. As depicted in Table (8), the overall mean of calving interval was 19.70±0.34 months; and no significant differences in the calving interval between camel breeds and successive calving seasons. However, camel ages show substantial difference in the calving interval, as she-camels age advanced the interval increased and this phenomenon was denoted up to the 6^th calving season (Table 8). Calving interval distribution among she-camel population is shown in Fig. (1). The calving interval classes were <15, 15-17, 18-20, 21-23 and >24 months and the corresponding percentages were 7.27%, 17.27%, 35.46%, 31.82% and 8.18% of the she-camels, respectively.

Table 1: Influence of camel breeds on the ages at first service, conception and calving (Mean±SE)

Table 2: Influence of camel breeds on the body weight at first service, conception and calving (Mean±SE)

Means in the same column with different superscripts differ significantly (P<0.05).

Table 3: Influence of camel breeds and ages on the interval between services (Mean±SE)

Table 4: Influence of camel breeds and ages on the post-partum period (Mean±SE)

Means in the same row with different superscripts differ significantly (P<0.05).

Table 5: Influence of camel breeds and ages on the service periods/days (Mean±SE)

Means in the same column with different superscripts differ significantly (P<0.05).

Means in the same row with different superscripts differ significantly (P<0.05).

Table 6: Influence of camel breeds and ages on the open days period (Mean±SE)

Means in the same column with different superscripts differ significantly (P<0.05).

Means in the same row with different superscripts differ significantly (P<0.05).

Table 7: Influence of camel breeds and ages on the number of services/conception (Mean±SE)

Means in the same column with different superscripts differ significantly (P<0.05).

Table 8: Influence of camel breeds and calving seasons on the calving interval/months (Mean±SE)

DISCUSSION

The reproductive function beginning by onset of puberty is affected remarkably by change in body weight. Attainment of puberty is influenced by the overall growth and weight of the animal which in turn is affected by nutrition (Marai et al., 2007). Ages at first service, conception and calving may constitute major reasons for the long generation interval in camels. In the present study,  the overall mean values of ages and weights at first mating, conception and calving were 39.75, 41.82, 54.39 months; 437.17, 450.16 and 519.03 kg, respectively. These results were in agreement with those reported in different countries as Magrebi Arabia, where the age at first conception and first calving were reported to be 37 and 49.4 months, respectively (Sghiri, 1988). Moreover, Mounir and Borni (2012) recorded age of first successful mating of Maghreby Negga camel varied between 33 to 48 months with an average of 39 months and the age at first parturition varies from 32-68 months. In Turkmenistan, Arvana camels mated for the first time at 3 years of age and 350-400 kg of live weight (Dmitriez and Ernst, 1989). In the Sudan, 66.7% of the female camels were bred at 3 years of age (Abbas and Musa, 1989). In the United Arab Emirates, ages at first service and calving were 43.1±0.58 and 55.3±2.87 months, respectively (Aboul-Ela 1991). In Libya, ages at first service and first calving were 36.9±1.10 and 50.3±1.28 months, respectively (Hermas and Shareha, 1991). In contrast, the current findings were less than 61-62 months which were reported for Bikaneri camels as age at first calving (Beniwal and Chaudhry, 1984 and Khanna et al., 1990). Moreover, in Pakistan (Yasin and Wahid, 1957); Indian (Khanna et al., 1990); Sudan (Köhler -Rollefson et al., 1990); Horn of Africa (Hartley, 1984) and Kenya (Karimi and Kimenye, 1990) the she-camels were reported to reach puberty at 4-5 years of age. The variation in these observations may be related to feeding and management and/or breed differences. However, the onset of puberty is remarkably independent on body weight. Therefore, dromedary camels reproductive performance in terms of age at puberty, at first conception and at first birth can be improved by ensuring adequate nutrition in early life and improvement of managerial and environmental conditions as well as by using hormonal treatment that can assist early sexual development and breeding maturity (Arthur and Al-Rahim, 1982; Simpkin, 1987; Zaied, 1991; Formigoni et al., 1996; Mounir and Borni, 2012).

The overall mean of the interval between services within the same breeding season which starts at early November to late April was 19.32±0.26 days. The present findings agree with those recorded by EL-Azab et al. (1997) where the mean interval between services within the same breeding season was 15.83±0.39 days.

The overall period from calving to first onset heat (postpartum period) was 45.39±2.57 days. Similarly, other studies indicating that the postpartum heat occurs 14-30 days after calving (Novoa, 1970; Evans and Powys, 1979; Abdel-Rahim and El-Nazier, 1992) and between 10-72 days with mean  26.34±1.89 days for Magarabi female camels (EL-Azab et al., 1997). In this study, it has been observed that the majority of female camels calved at the beginning of a breeding season came into the first postpartum heat after 13-103 days after calving within the same breeding season. It is importance to notice that in camels even with the early induction of heat after calving, the majority of females fail to conceive within the same breeding season, and this might be due to the effects of lactation, feeding status of the animals, body weight and conformation and feed availability (Shalash 1965; Shareha et al., 1982; Arthur, 1992; Mounir and Borni, 2012).

The overall mean of service periods was 74.58±3.62 days, came relative to value 51.9±12.1 days which recorded by Hermas and Shareha (1991) in Magrebi camel. In the present study, The overall mean of open days herein was 317.61±4.54 days, in accordance with  EL-Azab et al. (1997) and Hermas (1990), whereas open days period elapsed from calving to conception for Magarabi female camel were 308.02±6.95 days and 286.80±12.70 days. However, a recent study recorded shorter interval (147±131 days) between calving to successful mating of Maghreby Negga camel (Mounir and Borni, 2012).

The overall mean value of the number of services/conception was 2.57±0.02 services. Similarly, in Libya, Hermas and Shareha (1991) reported that services/conception was 1.84±0.15, while in United Arab Emirates, Aboul-Ela (1991) showed that the services/conception were 1.63±0.16 and the conception percentage occurred from first service was 58% and only 20% of she camels required ≥3 services before pregnancy. In this study and from the available observations it has been observed that in Saudi Arabia, camels' breeding season is started from early November to late April and it may extend to early May. During this period both males and females are fertile. On the other hand, summer months (July to September) are considered as a non-breeding season for local camel breeds (male and female) and the reproductive activities of camels were affected adversely by the heat stress and the function of the high ambient temperature (Habeeb et al., 1992; Marai and Habeeb, 1998 and Marai et al., 2002).

Long calving intervals are the most major factor contributing to poor reproductive performance of camels. Under extensive management system calving interval lasts for more than 24 months (Evans and Powys, 1979). However, the calving interval of camels may reach eighteen months, similar to that of cows (Knoess, 1976). The overall mean of calving interval was 19.70±0.34 months; and no significant difference in the calving interval between camel breeds and successive calving seasons. These results are in agreement with that reported by Basmaeil et al. (1994) in Saudi Arabia where the calving interval for five successive breeding seasons was 20.58±0.82 months. Similarly, Mounir and Borni, (2012) cited that, the intervals between calving of Maghreby Negga camel was 526±145 days. Moreover, Dmitriez and Ernst (1989) in Turkmenistan obtained in their study 2 calves/3years. As well as, in Kenya, Evans and Powys (1979) observed an average calving interval of 22 months if young survives. In the same purport, the present findings were longer than those reported by Richard et al. (1985) in Niger (15.0 months); Mosleh (1991) in Tunisia (13.45±0.27 months) and Köhler-Rollefson (1991) in Sudan (14-15 months). In contrast, the present calving interval was shorter than those recorded by Aboul-Ela (1991) in United Arab Emirates (24.4±0.68 months); Khanna   et al. (1990) in Indian (25.73±0.27 months);  Hermas and Shareha (1991) in Magrebi Arabia countries (22.62±0.40 to 24.0±8.2 months); Dioli (1991) in East Africa (24.0 months); Aslam et al. (2002) in Pakistan (23.5±1.33 months); Schwartz et al. (1983) in Kenya (28 months) and Herren (1993) in Somalia (29 months). The disagreement of these observations was attributed to differences in she camels' gestation length and seasonality of breeding (Wilson, 1984 and Arthur et al., 1985); late post-partum estrus (Mukasa-Mugerwa, 1981) and individual variation in open days period (Aboul-Ela, 1991).

Among the studied camel herd, the calving interval distribution classes were <15, 15-17, 18-20, 21-23 and >24 months with corresponding percentages were 7.27%, 17.27%, 35.46%, 31.82% and 8.18% of the she-camels, respectively. Similarly, in Mali, Swift (1979) reported that, 20.9%, 27.9%, 44.2% and 7.0% of a herd of she-camels showed calving intervals of ranges 12-15, 16-23, 24-25 and >25 months, respectively. Also, in United Arab Emirates, Aboul-Ela (1991) indicated that the intervals between calving is <20 months for 14.4% of she-camels. Moreover, in Kenya, Bremaud (1969) demonstrated, 11.5%, 3.9%, 53.5% and 30.8% of  she-camels herd with calving intervals 12-15, 16-23, 24-25 and >25 months, respectively. Herren (1993) reported that in Somalia a period of 28 months was estimated as a calving interval in 35-40% of a herd of she-camel. Generally, the current calving interval showed 3 types of calving intervals. Short calving intervals of the average 14 months that was observed to correlate with breeding female camels aborted at late stage of pregnancy and in cases of calf death after delivery. In this case, the dam was submitted to a bull camel for conception within one month. The medium calving interval (between 16 and 18 months) was seen when the female camels delivered at the beginning of the breeding season, and calves were weaned as early as 75 days of age, and their dams were rebred and became pregnant at the end of the same season. Long calving interval (≥23 months) was observed when the female camels were kept milking to satisfy the milk demand of the calves.  

CONCLUSION

Reproductive traits, in terms of post-partum period, service period and open days are dependent on the  camel breeds, and this indicates the importance of  heritability as a value that express and measure average additive gene effect. However, further research is needed to determine the correlation between genetic merits of camel breeds and total productivity including reproductive performance, which may be better in some camel breeds than others.

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