Growth Performance and Hair Mineral Status of Marecha (Camelus dromedarius) Calves Reared under Different Management Systems

Growth is defined by Schloss (1911) as a “correlated increase in the mass of the body in definite intervals of time, in a way characteristic of the species”. In normal life of an adult animal, its optimum performance depends upon its optimum growth. Meat animals will make economic gains only in that condition if they are raised well. If the breeding females have not been grown properly they might have impaired breeding ability. It is obvious that one cannot expect the satisfactory yields and performance from cattle, buffalo, sheep, goat and camel unless they were well fed and well developed during their growing period (Ensminger, 1991).

Several studies have indicated the potential of rapid growth rate in early life of camel calves under various conditions (Degen et al., 1987). The species which provide milk or meat like camels are considered having natural phenomena of efficient daily weight gain in their early life. This intrinsic ability of animal is governed by its genetic makeup and can be supplemented by adequate feeding and management.

Camel is a favorable source of meat in many areas of world such as Egypt, Libya, Sudan and Gulf countries (Turki et al., 2007). The demand for camel meat appears to be increasing due to health reasons since it produces carcasses with less lipids (1.2-1.8% vs. 4.0-8%), less cholesterol, high water contents (5-8%more) and relatively higher polyunsaturated fatty acids (PUFA) than other meat (Kadim et al., 2008; Mohamed and Manal, 2012; Mounir et al., 2012; Ahmed and Yetim, 2012). It is being used as remedial purposes in the treatment of many diseases such as hypertension, hyperacidity, pneumonia, respiratory diseases and as an aphrodisiac (Kurtu, 2004). It is an important staple and essential component of the life of pastoralists. There is an emerging interest in slaughtering of young camel calves (around 1-2 year of age). Camel meat has been scored as better than beef by taste panels in Arab states. Lucrative export opportunities to Sudan, Kingdom of Saudi Arabia, Libya, Egypt and Gulf states do exist.

Mineral estimation in camel hair is comparatively a newer concept in Pakistan. The study of mineral profile gives fruitful information about the general health status of the animal so could be used as an indirect tool for evaluation of nutritional status and well-being of an animal. Camel hair accumulates all important minerals and is commonly available tissue which can easily be collected, stored, transported and if needed can easily be resampled. Present study was conducted with the objective to investigate the influence of management systems on growth performance and level of important macro and micro minerals in hair of camel calves.

The study was undertaken during the year 2014 at Camel Breeding and Research Station (CBRS), Rakh Mahni, Tehsil Mankera, District Bhakkar, Punjab. The CBRS is located in Thal area between 31° 10’ and 32° 22’ North Latitude and 70° 47’ and 72° East Longitude. Most of the area lies in the desert plain of the Thal. This area is included in the Agro Ecological Zone-III A and B (sandy desert area) having narrow strips of sand ridges and sand dunes. The climate is arid to semi-arid subtropical continental and means monthly highest temperature goes up to 45.6 ºC, while in winter it goes from 5.5 to 1.3 ºC. Mean annual rainfall in the region ranges from 150-350 mm, increasing from South to North (Rahim et al., 2011).

Twelve Marecha calves (Camelus dromedarius) around 330±30 days of age (born during months of January to March 2013) were allotted randomly to two comparable groups of 6, each containing 3 males and 3 females so the group was composed on homobreed and heterosex calves. The animals in the first group were fed concentrate @ 1 kg/h/d along with crop residues of gram (Cicer arientinum) round the clock, considered as IMS. The DM, CP, TDN, NDF and ADF of concentrate were 90.32, 18, 66, 29, 14.41 % while ME was 2.41 Mcal/kg DM, respectively. In second group all animals were sent for grazing/browsing daily for about 8 h (8-16 h) while rest of the time were stall-fed with the gram crop residues ad lib and considered as SIMS. Water was provided twice a day in both the systems.

Before the start of the experiment all the calves were marked for identification and were dewormed to reduce the parasitic load. Calves were housed in semi-open pens throughout the trial. Initial body weight of the camel calves were recorded before shifting these calves to the respective treatment groups and thereafter all the experimental calves were weighed fortnightly before morning feeding. The calves were weighed on a set date before morning feeding on computerized weighing scale. The growth rate of the calves was calculated from fortnightly weighing by using the formula as (current weight-previous weight/15). The feed intakes of stall fed animals were calculated as the difference between the residual amount of feed and the amount offered. The average dry matter values of feed were measured and the dry matter intake was then determined.

The crop residues and herbage samples of the grazing/browsing material were analyzed for percent dry matter, crude protein, crude fiber, ether extract and ash (AOAC, 1990). Neutral detergent fiber (NDF) and acid detergent fiber (ADF) was also determined (Van Soest et al., 1991). Hair samples were collected from shoulder, neck, hump and mid region of body of camel calves. The hair was cut with the stainless steel scissors into pieces of about 1 cm length from each region and mixed well to ensure homogeneity. The skirting of sample was done properly. Samples were washed with acetone and filtered, rinsed with plenty of water. These were dried in hot air oven and 0.5 g of dried mass was taken for further processing. Concentrated nitric acid (2 ml) was added to each hair sample and was kept at 100 °C until half of the total volume evaporated. The samples were taken out and cooled. Concentrated per-chloric acid (2 ml) was added and again the sample was kept until half of the total volume evaporated. After this procedure, distilled water was added to give a total volume of 10 ml (Bhakat et al., 2009). The solution was used for determination of important macro-minerals and micro-minerals. The concentration of macro (Ca, Cu, Mg) and micro (Fe, Mn, Zn) minerals was determined by atomic absorption spectrophotometer (AOAC, 1990).

Data collected on different parameters were analyzed by Fisher’s analysis of variance technique having 2×2 factorial arrangements of treatments under CRD using SPSS software (SPSS, 2008). Tukey’s test at 0.05 levels of significance was used to compare the differences among the treatment means (Steel et al., 1997).

IMS, intensive management system; SIMS, semi intensive management system. Means having different superscript in columns are significantly different (P<0.05).

The calves of similar weight and size were selected in both management systems for this study. After 120 days of trial period overall weight gain was 80.83, 77.83 and 50.33, 45.16 kg in male and female calves reared under IMS and SIMS, respectively. The daily weight gain (growth rate) was 0.674, 0.649 and 0.419, 0.376 kg/d in male and female calves reared under IMS and SIMS, respectively. Overall weight gain and growth rate of male and female calves in IMS and SIMS are presented in Table I. The average growth rate was significantly higher (P<0.05) in calves of IMS as compared to the calves of SIMS. These findings are in line with the findings of Bhakat et al. (2008) who studied the effect of management systems on growth performance of dromedary camel calves in India, they used 10 camel calves aged between 7-10 months old in their study and divided them randomly into two comparable groups of 5 each. The average initial body weight of both groups was almost similar. The groups were of hetero breed and hetero sex combinations, each group contained 3 Jaisalmeri, 1 Bikaneri, 1 Katchi breed and 4 males and 1 female. At end of the trial, average total gain was almost double in ISM than SISM group. The average growth rate was significantly higher in ISM (611 g/d) than SISM (319 g/d).

In present study, male calves attain higher weights in both the systems, may be due to the reason that more receptors are present on muscle cells for androgens that accelerates the growth (Hossner, 2005). These findings are supported by the findings of Knoess (1977) and Qureshi (1986) who reported average daily weight gain as 1.4 kg in male, 0.95 kg in female; 1.5 kg in male, 1 kg in female camel calves, respectively in Pakistan. Musavaya (2003) reported weight gain in calves as 0.41 kg/d in males and 0.38 kg/d in females while weight gain after the sexual maturity as 0.12 kg/d in males and 0.06 kg/d in females. Kurtu (2004) reported that mature male calves were heavier than female calves by 38%. Indian scientists Sahani et al. (1998) reported average daily gain in 0-3 (0.63, 0.58); 3-6 (0.64, 0.62); 6-9 (0.37, 0.39); 9-12 (0.23, 0.23); 18-24 (0.16, 0.20); 24-30 (0.16, 0.17) and 30-36 months (0.18, 0.14) kg in male and female calves, respectively. Male calves weighed more than females. A significant contribution of sex and year in Bikaneri camels has also reported by Baniwal and Chaudhary (1983). Khanna et al. (2004) reported average daily gain (ADG) as 0.7 and 0.77 kg in Jaisalmeri and Bikaneri Indian camel breeds from birth to 3 months of age, respectively. However, no significant difference was found to be in male and female calves regarding their daily weight gain. Ouda et al. (1992) observed that regarding growth sex and year affects significantly after two years of age.

Current findings are in accordance with the findings of Saini et al. (2014) who also reported higher total and average daily gain (kg) in stall fed pre-pubescent camels as compared to grazing group. In Sudan, Mohamedain et al. (2015) studied growth performance in dromedary camels under two feeding regimen. First was zero browsing group (15 Darfuri and 10 Butana) fed complete ration (sorghum 50%, groundnut cake 15%, wheat bran 5%, molasses 10%, dura husk 5%, bagas 12%, urea 2% and common salt 1%) to provide ME @ 11 MJ/kg DM and 16% CP. Second was free browsing group with same breeds without any supplement. The trail was of 120 days with two weeks as adaptation period. The average total weight gain was almost double in zero browsing group (96±17.3 kg) than free browsing group (42±19.5 kg). ADG was 800 g in zero browsing group as compared to 350 g in free browsing group. While in present study, lower daily weight gain was observed in IMS due to the limited supply of concentrate.

Current findings are not in line with the findings of Bhakat et al. (2009) who reported that the average daily gain (g/d) differed significantly among two systems, being higher in semi-intensive system of management as (325 and 476 g/d) than intensive system of management as (278 and 331 g/d) with guar phalgati (Cyamopsis tetragonoloba) and moth chara (Phaseolus aconitifolius) feeding, respectively. Bakheit et al. (2012) reported significant differences in the mean daily weight gain (grams) under semi-intensive (535±9.83) and traditional management systems (TMS) (317±5.46), respectively. In Kenya the calves under TMS gained 222 g/d to 6 months age in dry season and 655 g/d in wet season (Field, 1979) while Zeleke and Bekele (2001) reported range for average daily growth rates of camel calves as 0.72-0.86 kg. Under proper nutrition ADG in camel calves has been reported as 0.87 and 0.57 kg from birth to 30 days and from birth to 180 days, respectively by Wilson (1992) while El-Badawi (1996) reported ADG as 0.83-0.97 kg from birth to 180 days in Egyptian dromedary calves.

The findings of the present study are supported by Hammadi et al. (2001) who reported 580 grams daily growth rate between births to 90 days age, while Bissa et al. (2000) reported growth rate as 733 g/d from birth to 180 days in Indian dromedary camels. The average daily gains in 2 months old Bikaneri and Jaisalmeri calves were 553.3 and 546.6 g, respectively as observed by Sahani et al. (1992) in India under TMS. Nagpal et al. (2005) reported ADG as 377.6-420.9 g/d in Indian camel calves at 10-12 months age under TMS. Kamoun (1995) reported a daily growth rate of 260 g/d in camels fed only on mangroves and 550 g/d in camels fed on high dietary protein and energy diet. Average daily weight gain was 0.74 kg during 90 days in Saudi camel calves when they were fed 75% concentrate and 25% hay (Al-Saiady et al., 2006).

Average daily intake was found to be significantly varied (P<0.05) among calf groups between intensive and semi-intensive management system (6.93±0.45, 6.37±0.45 and 4.09±0.46, 3.83±0.46 kg) in male and female calves, respectively (Table II). These findings are in line with the findings of Bhakat et al. (2008) who studied the effect of management systems on growth performance of Indian camel calves and reported that the crop residue intake was significantly varied between two groups, 5.53 vs. 4.37 kg/calf/d in intensive system of management (ISM) and semi-intensive system of management (SISM), respectively. Moreover, Saini et al. (2014) reported higher DMI (kg/d) in stall fed pre-pubescent camels as compared to grazing group. The proximate analysis of crop residues and herbage samples available for grazing/browsing is shown in Table III.

The mean values were found to be significant (P<0.05) for calcium, magnesium, copper, zinc, iron and manganese in male and female calves under intensive and semi-intensive management system, respectively (Table IV).

It is an indirect tool for measuring the general health status of the animal. As the animal gained higher weight, definitely there will be higher mineral accumulation in wool. Very less work has been done on wool mineral analysis in camel calves. Indian scientist Bhakat et al. (2009) determined hair mineral status of camel calves reared under different management systems and reported higher concentrations of macro and micro minerals in calves of semi-intensive management system. They reported calcium (549.60±74.45, 434.40±60.21 and 719.72±78.62, 476.00±127.98), magnesium (88.92±2.41, 67.60±6.33 and 77.48±3.67, 69.84±3.18), copper as (6.16±0.72, 4.30±0.44 and 7.36±0.66, 5.72±0.99), zinc (66.04±4.38, 57.56±2.33 and 64.25±2.04, 54.76±1.46), iron (285.72±26.55, 216.08±30.89 and 319.36±27.91, 261.92±33.37) and manganese (21.56±3.65, 20.60±1.02 and 45.80±1.83, 32.92±4.36) mg/dL in calves reared under semi-intensive and intensive management system with guar phalgati (Cyamopsis tetragonoloba) and moth chara (Phaseolus aconitifolius) feeding, respectively. Furthermore, Chattergee et al. (2005) found different status of manganese in hairs of Yak. In horse, levels of some elements were affected to a higher or lower degree by nutritional differences as reported by Or et al. (2004).

ADI, Average daily intake; Means having different superscript in columns are significantly different (P<0.05).

ADF, Acid detergent fiber; CP, Crude protein; CF, Crude fiber; DM, Dry matter; EE, Ether extract; NDF, .Neutral detergent fiber

Means having different superscript in columns are significantly different (P<0.05).

Internal metabolic environment like blood, lymph and extra cellular fluids plays role in the development of camel hairs, as all the constituents enters into body accumulates in hairs and reflect exposure record of nutritional and toxic metals intake. The mineral status of camel hair can efficiently be used as tool indicator of mineral deficiency in soil. Also the level of these minerals could be used in the diagnosis of various diseases, metabolic disorders and nutritional status of the camel calves. The findings of present study indicated that higher growth rate was achieved in intensive management system than semi-intensive management system. Regarding sex, male claves were found to be heavier than female calves in both management systems. Along with that, the hair mineral status also confirmed the results. It is concluded that Pakistani camel calves has great potential that could be exploited by modern husbandry practices according to scientific lines that will be a useful addition to the food chain.

The help and support by management of Camel Breeding and Research Station (CBRS) Rakh Mahni, Tehsil Mankera District Bhakkar and financial support of Higher Education Commission (HEC) Islamabad, Pakistan, for this study are gratefully acknowledged.

Authors have declared no conflict of interest.