Feeding Camels on Halophytic Plants andTheir Effects on Meat Quality Characteristics and ProductsM.
F.Shehata* Abstract Camelsare adapted to the conditions of arid and semi-arid areas, compared to other animalspecies. Camels have the ability to utilize feed resources availablein these areas such as halophytes and convert them into meat and milk and otherproducts. Feeding halophytes particularly to camels is afeasible solution to minimize the problem of feed shortage in Egyptian arid andsemi-arid regions, where desert represents about 96% of the total area.
Thischapter sheds light on the effect of feeding camels on some halophytic plants (Acacia,Atriplex) and their relationship with the physical, chemical, organoleptic properties ofcamel meat under Egyptian conditions. Also, it covers the impact of feeding such forage ondaily gain rate, feed conversion efficiency in additionto the economic evaluation. The dressingpercentage, edible and non-edibleparts and wholesale cuts of camelcarcass are also discussed. Accordingto the nutritional and economical results, the use green edible parts ofhalophytic plants (Acacia andAtriplex) with adjustedconcentrate mixture (ACM) in feeding growing camelsis economically efficient for meat production with no adverse effects onquantity and quality meat characteristics.Keywords: meat quality, halophytic plants, Acacia, Atriplex,dressing percentage,wholesale cuts, daily gain rate, feed conversionefficiency, edible and non-edible parts.
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com 1. IntroductionCamelsplay an important role in the desert ecosystem because they represent one ofthe natural resources in these areas. On the other hand, producing highquantities of meat for human consumption is vital in developing countries.Camels are a good potential source of meat because they yield reasonably heavycarcasses under inexpensive management systems1. Therefore,it is inevitable to develop the production of camels in Egypt.
This might becarried out through widening the production of meat and milk and maximizing thebenefit of these products by adopting proper processing methods in order toenable this type of animals to play a significant role in narrowing theexisting gap in animal protein.Thedromedary camel receives much appreciation as a valuable meat-producing animalin many parts in Egypt, Saudi Arabia and Libya2.The dromedarycamel is an economic feeder, which can uniquely exist in the desert as aproducer of meat, milk and other by-products.
Camels can feed on natural feedresources that are unsuitable for other species. Foodsecurity is becoming an important issue throughout the world, particularly inthe developing countries. Most of these countries have started to control theirnatural resources to achieve this goal. Meat and milk are the main sources ofanimal protein being rich in essential amino acids and other nutrients requiredfor normal growth and human health.Meatprice is dramatically increasing in most developing countries mainly due to thedevastating increase in human population and the relative decrease inanimal population as well as low productive efficiency.Generally,animal production is constrained by many factors such as scarcity, higherprices and poor-quality of feed resources, and adverse climatic conditionswhich lead to frequent and extended drought periods3.Halophyticand salt-tolerant plant species can offer a range of nutrients for animals;provide a valuable reserve feed for grazing animals particularly under droughtconditions or fill feed gaps caused by seasonal variations.
In arid and semi-arid areas, sheep, goats andcamels are generally accepted as valuable meat and milk-producing animals,especially in the marginal areas. These animal species can survive theprevailing harsh conditions in the desert regions and are capable of convertingthe poor and irregular growth of vegetation into meat and other products. Feeding halophytes particularly to camels isa feasible solution to minimize the problem of feed shortage in Egyptian aridand semi-arid regions, where desert represents 96% of the total area. 2.The used halophytic plants Thefuture prosperity of feed resources in countries located in the arid andsemi-arid regions rely on the economic feasible use of marginal andlong-neglected resources such as halophytic plants. Halophytic plants used asanimal feed have a good potential as feed resources4.
Halophytesinclude several forages and salt tolerant grasses and legumes of highproductivity, rapid tender and suitable nutritive value5. 2.1. AcaciasalignaAcaciaspeciesare naturally wide spread in arid and semi-arid zones of Africa, fromSenegal to Egypt and down to the South Africa, as well as in some othercountries in Asia6.
Acacia saligna is an ever-green legume shrub and the moredominant species in Egyptian deserts7. Itcontains high crude protein, high fiber content and condensed tannins, whichdecreases the availability of protein8. 2.2. Atriplex nummularia Atriplexnummularia is an important saltbush, with a great biomass yield, high crudeprotein, low crude fiber and high resistance to salinity9-10, but, it is deficient inenergy. So, animals fed Atriplex spp. should be given an energysupplement, e.
g., barley grain, yellow corn grain, date seed11-12. Atriplexnummularia is a good green fodder for camels whensupplements with suitable source of energy at a level not less than 40% oftheir maintenance requirements especially during dry seasons in arid andsemi-arid areas13. 3.Camels breeds in Egypt Camel breed types raised in Egypt are conventionallyclassified according to their phenotypic and production characters into fourbreeds namely Fallahy, Sudani, Mowalled and Maghrabi (Fig.2) all of them belongto dromedary camel14.Thecamel meat breeds can be characterized asthe development of the hindquarters, large hump, rigid body, relativelyshort neck, large head, heavy bones and muscles15-16. Proteinpolymorphism and five RAPD-PCR primers were used to characterize four camel breeds inEgypt, which are Fallahy, Maghrabi, Sudani and Mowalled according to Ismail17.
It was concluded that meat type camels may be obtained by selection for thecharacteristics of large chest girth, short neck, body length, low height atwither, height at hump and small pelvic cavity.4. CamelmeatAcamel carcass can provide a considerable amount of meat for human consumption. Howeverthe carcass characteristics of camels vary considerably owing to differences inage, sex, breed, and type and health status.
The characteristics depend mainlyon live weight and management practices and the conditions of the vegetation1.The role of the camel as a meat producer is becoming more evident because ofthe resource ful role it plays rather than as a symbol of social status. Themarketing system for camel meat is not well organized. There is an evidence ofhigh demand for fresh camel meat as well as for camel mixed meat products, evenamong societies here. Camel herding does not take place representing anotherproblem relating to camel meat production. Also, the lack of information oncarcass quality is a hindering problem.
In general, meat quality characteristics of young camelsare comparable to those of beef18-19-20-21-22. An increase in meat toughness, a reduction in thepalatability and quality were reported to increase with age23-24-20 . Camel meat is termed as raspberry red to dark brownin color with a sweet taste due to its high glycogen content1.5. The experiments DescriptionIn successive studies by Shehata, et al25,Shehata26 and Shehata, et al27 evaluatedthe use of some non-conventional feedstuffs in fattening trails using male camels. where the experimental treatments were as follows: Camels of the first group(control) were fed traditional concentrate mixture (TCM), while the other fourgroups were fed adjusted concentrate mixture (ACM) by introducing both grounddate stones and olive cake (20 and 10%, respectively). Both concentrate mixturewere offered to camels at level of 125% of maintenance requirements asrecommended by28. The control group was offeredberseem hay (BH), while the other four groups were offered fresh Atriplexnummularia (AN), Acacia saligna (AS), Atriplex nummularia alongwith Acacia saligna (AN-AS, each ration in different container andcamels selected by free choice) and ensiled rice straw (ERS).
These series ofexperiments evaluated the influence of such feedstuffs on the performance ofgrowth, carcass characteristics and meat quality, as well as the economicevaluation. 6. Effect of halophyticplants on camel performance Researchinformation regarding the impact of feeding halophytic plants on camelperformance in respect of the daily gain, feed conversion efficiency andeconomic evaluation are available.6.1. Daily gain of live body weightMany factors influencethe camel’s growth rate as well as breed, nutrition, sex and health.Shehata et al25pointed out that theAverage daily gain (ADG) of camels ranged from 525 gm for (AN) ration group to828 gm for control ration group. However, significant differences (P?0.
05)observed in daily gain among camel groups fed different rations containing BH, AN,AS, AN-AS and ERS. Regardless of control group fed BH, the camel group fed ASration showed the highest ADG (719 g/day) followed by AN-AS group (680g/day),ERS (589g/day) and AN (525 g/day) groups. These results indicated that ADG wassignificantly (P?0.05) affected by the type of both roughages and concentratecomponents. In another study, Shawket29 foundthat growing male camels fed rations containing fresh ( Atriplexhalimus) with ground barley grains equal to 100% oftheir maintenance requirements for energy, had an ADG of 732.2 g/ day. Thisrate of growth was higher (525 g/ day) than those fed Acacia saligna.The difference could be attributed to the type of halophyte and concentrate.
Barely grains had higher content of energy (Nitrogen Free Extract, NFE)=77.8%)than that of ACM (NFE= 66.10%). In addition, halophytes are known to bedeficient in energy11. 6.
2. Efficiency of feed conversion Feedconversion efficiency is defined as ratio of the weight of food required toproduce unit gain in the live weight of animal. Resultsof the study conducted by Shehata et al25showed that thereareno significant differences (p?0.05) among groups fed rations containing BH, ASand ERS in DM conversion. The corresponding values were 8.
93, 9.08 and 8.91KgDM/ kg gain, respectively. The other twogroups AN and AN-AS were significantly less efficient in feed conversion withvalues 12.
76 and 11.83 kg DM/ Kg gain, respectively. Regardless of the BH control group, feed conversionof AS and ERS groups were greater than the other halophytes fed groups Theseresults are in agreement with those found by30 for rice straw withconcentrate mixture (Crude Protein, CP)=14%) and31 for Acaciasaligna with barely grains. These values of Dry Matter Intake (DMI)conversion into weight gain were almost within the range reported by32;being between 6.3 and 11.9 Kg in camels (at one year old) fed hay ad libitumplus concentrate mixture (80% wheat bran). On the other hand, the presentvalues of DMI conversion were more efficient than those obtain by33who reported 13.
52 and 14.57 Kg DM /Kg gain for the camels fed berseem hay andwheat straw with concentrate, respectively. Feedconversion efficiency of three groups of fattened male camel calves (averagebody weight, 178 Kg) fed saltbush (Atriplex halimus) with differentenergy sources for 180 days was evaluated by29. The camels wereoffered concentrate mixture + berseem hay (A); barley grain + fresh saltbush(B) and barley grain + olive cake + fresh saltbush (C). The results indicatedthat feed conversion in terms of kg total digestible nutrients (TDN)/kg weightgain and kg digestible crude protein (DCP)/kg gain improved for animals fedsaltbush (Atriplex halimus) in(B) and (C) groups which led to an appreciable reduction in feeding cost forproducing one-kg of body weight.
The author concluded that fresh saltbush whichis naturally available in many arid areas can be successfully andeconomically used in feeding camel calves provided that available energysources are added to balance the diets.6.3.Economic evaluation Economicefficiency was expressed as the ratio between the monetary value of total liveweight gain and the cost of feeds consumed. Accordingto the results of the economic evaluation in the experiment of feeding growing male camels25, itwas noticed that halophyte including rations were cheaper than the controlration. The cost of feeding camels to produce one kilogram of weight gain was7.
45, 5.28, 3.94, 4.25 and 5.52 Egyptian pound (LE) for rations BH, AN, AS,AN-As and ERS, respectively.
These results indicated that feeding male camelson rations AN, AS, AN-As and ERS, reduced the cost of feeding by 29.13, 47.11,42.95 and 25.91%, respectively compared to control group. Moreover, the rationAS showed comparable value of ADG with that obtained from control ration (BH)and it seemed to be the least in feed cost (LE 3.93), showing the highest economicefficiency (177.70%) as shown in Table (1).
7. Effectof halophytic plants on meat yield of camelsA camel carcass canprovide a considerable amount of meat for human consumption. However thecarcass characteristics of camels vary greatly owing to differences in age,sex, breed, feed type and health status. The characteristics depend mainly onlive weight and husbandry practices and the condition of the vegetation1.
The role of the camel as a meat producer is becoming more evident becauseof the resourceful role it plays rather than as a symbol of social status.Littleresearch information is available concerning the effect of feeding suchhalophytic plants on dressing percentage, wholesale cuts, physical componentsand fat deposits in camel carcass. 7.1. Effecton dressing percentage Dressingpercentage is a direct function of the yield of meat from the animals. It variesdue to many factors such as age, weight, fatness, type of diet, dressingprocedures, and degree of gut fill at slaughter1. In thecamel, dressing-out percentage ranges from 55 to 70%18-34-35.
In a study conducted by Shehata, et al.25the use of some non-conventional feedstuffs (fresh Atriplexnummularia, AN and /or Acaciasaligna, AS and ensiled rice straw, as roughages), wereevaluated in a fattening trail using male camels, and their effectson dressingpercentage (Table 2). The results indicatedthat the group of camels fed AN-AS had significantly (p?0.
05) higher hot andchilled dressing (70.61 and 68.17%) than those of the other tested groups basedon empty body weight. It was noticedthat even the lowest dressing percentage values of camels group fed AN wasslightly higher than those values obtained by Shawket29 on yearling male camels fed Atriplex halimus; being59.
02 and 66.10%, respectively. These results indicated that dressingpercentage of growing male camelswere higher than those reported by36-37 on camel calves fed concentratemixture with hay or rice straw which had dressing percentage ranged from 51.10– 52.66 and 61.00 – 62.
71% either based on slaughter and emptybody weight, respectively. 7.2. Edibleand non-edible partsData available onedible and non-edible parts of the camel are limited. Proportions of liveweight of feet and hide are higher in the camels than in cattle, but the camelhead proportion is lower than in cattle38-39.Theresults obtained by Shehata, et al.
25 showedthat the groups fed AN and AS rations recorded thehighest percentages in the edible parts compared to other groups yet, thedifferences were not significant. While, the group fed AN showed the highestnon- edible parts percentage, the AN-AS fed group had the lowest one (Table.2).
7.3. Effect on wholesale cutsCuttingsystem is defined as the best method we can apply to reach an easy system ofcutting high-price cuts according to the economic traits which are determinedby testing traits and percentages of lean meat to other contents. Differentcuts may be classed according to the percentages of bones and fat removed.However, there is no standard cutting system for camel carcasses such as that forthe other meat animal species40. The carcass side was dividedinto forequarter and hindquarter by cutting between the 11th and 12thribs41. The forequarter is usually divided into five wholesale cuts(neck, shoulder, brisket, rib and plate), while the hindquarter is divided intothree wholesale cuts (loin, flank, and leg). The fore- and hind-quarters for the left side of the carcasses were cutinto different wholesale joints.
Cuttingprocedurea adopted was that of 42. Thefore-quarter cuts included six cuts: neck, shoulder, fore-shank, fore-ribs,flat ribs and brisket, while the hind-quarter included seven cuts: handshake,loin, flank, flit, flank, leg and hump to produce a total of thirteen wholesalecuts (Fig. 3). Weights of the wholesale cuts were recorded and percentages ofchilled carcass weight were calculated.
The different wholesale cuts proportionsare economically important. The high-priced cuts in carcass are known to be oneof the primary measures for carcass quality, which define the value of thecarcass. Results for wholesale cuts which reported by Shehata,et al27 showed that the brisket and shoulder cuts % differedsignificantly (p?0.05) due to type of feeding, while the other wholesale cuts (highpriced cuts, fore- and hind-quarters) showed no significant difference. Also,the authors found that the shoulder cut in AS-AN fed group had the highestweight (24%), however it decreased in the BH, AN, AS (23.
01, 22.23 and 20.17%),respectively. The brisket cut increased from 4.79% in AN group to 5.05, 5.59and 6.
39% in BH, AN- AS and AS groups, respectively. The percentage ofhigh-priced cuts were 42.00, 43.27, 43.58 and 40.
87% for BH, AS,AN and AS-AN groups, respectively. Similar results concerning wholesale cuts ofcarcass in one- humped camels were obtained by43.The results of the physicalcomponents of whole carcass in a study conducted by Shehata, et al27 indicated that the leanmeat, fat, bone and boneless meat were significantly(p?0.05) affected by type of feeding.
The group that was fed Atriplexnummularia (AN)had higher lean meat percentage (58.13%) and lower fat percentage (22.01%) thanother groups. Values of lean meat, fat, bone and boneless meat of camels fedexperimental diets showed ranges from 54.35 – 58.
13, 22.01 – 28.70, 17.34 –19.85 and 80.25 – 82.64%, respectively.
These values were approximately similarto those found by44 for fattened male camels. 8. Effectof halophytic plants on meat quality of camelsManyconsumers define meat eating quality in terms of tenderness and juiciness, withmore tender and juicy meat having higher eating quality. However, in mostinstances, flavor of meat is also used to help determine acceptance. 8.1.
Effecton physical meat quality characteristicsPhysical meat qualityproperties (color, pH value, cooking loss, water-holding capacity (W.H.C),plasticity and expressible fluid percentage) were determined. Theusing the halophytic plants particularly Atriplexnummularia in camel feed can improve the physical properties of meataccording to Shehata26.
Cooking loss of camel meat of Acaciasaligna fed group was significantly lower (P > 0.05) than other groups.The range of cooking loss (40.80 – 42.
96%) for the experimental groups issimilar to that (40.57 to 43.04%) obtained by45 and higher than that(3.
3.23 – 37.95%) reported by46. Such difference might be due totype of feeding, weight at slaughter, age, sex, carcass weight and degree offattiness and/or cut47. Acaciasaligna fed group was better in water holding capacity and plasticity thanthe other feeding groups. The pH values of camel meat differed significantly (P?0.
01)by type of feeding ranging from 5.55 to 5.81; these values were in agreementwith46. 8.2.
Effecton chemical meat quality characteristics Chemical composition of meat has asignificant economic importance for both producers and consumers. However,camel meat varies in chemical composition according to breed type, age, sex,weather, slaughter weight, degree of fatness, site on the carcass and type ofcut or muscle used for analyses48-1-40. Chemical composition (moisture,protein, fat and collagen) of the Longsimus dorsi (L.D) muscle wasdetermined using Food Scan Pro meat analyzer (Foss Analytical A/S, Model 78810,Denmark). Ash content was determined using a muffle furnace at 600?C for 8 hours.The results reorted by Shehata26 showed that the chemical composition of fresh camelmeat is affected by type of feeding.
The moisture content in camel meat showedsignificant differences due to type of feeding, (73.44, 71.22, 70.81 and 71.23%)for BH, AS, AN and AS-AN), respectively. Meat of camels fed AN had the lowestmoisture content than other experimental groups, where this was due to itshigher fat content. The protein content of camel meat did not differsignificantly by type of feeding while the fat content of camel meat differedsignificantly.
Meat of camels fedhalophytic plants had the higher fat content than the other control group.The ash content of camel meat differedsignificantly by type of feeding. In spite of the high content of ash of thefed halophytes, they had no effect on ash content of camel meat. On the basis of these results, camel meatappears to be similar in chemical composition to other red meats. Comparableresults were found for lamb, veal and beef 49. Generally, the nutrient content of camelmeat is similar to those reported for other red meat except that meat of ANgroup had higher level of fat.
8.3. Effecton sensory meat quality characteristics The effect of feeding ofhalophytic plants (Atriplex and Acacia) on the sensory characteristicsof camel meat was evaluated (Shehata26). Significant differences (p?0.10) for the aroma, flavor, tenderness, and juiciness were observed amongfeeding groups. The meat of camels fed BH and AN had higher score in meatacceptability than those from other groups. The sensory properties of samplesfrom camels fed AS and AS-AN groups agreed with those reported by45.However, the values of samples from camels BH and AN groups were higher thanthose reported by the same author.
9. Effect on camel meat processing Tenderness,taste and palatability of camel meat products could be increased by the processingof the meat produced from camels fed saltbushes50. It wasrecommended that camel meat could be processed in the way as beef meat withsimilar consumer products leading to increased cash flow for camel meat, whichis cheaper than beef. Simliarly, the effects of feeding of salty plants(Atriplex and Acacia) on the chemical, physical and sensory characteristics ofcamel basturma prepared from Biceps femoris muscles was studied51.It was found that basturma produced from camels in Acacia group had the highestprotein content and the lowest fat content. However, no significant differenceswere found in Thiobarbaturic acid values of fresh basturma processed from camelmeat fed on different types of roughages. Basturma processed from Atriplexgroup had the highest sensory score for any attributes followed by basturmafrom control and Acacia groups.10.
ConclusionAccording to the nutritional and economical results,the use green edible parts ofhalophytic plants (Acacia andAtriplex) adjustedconcentrate mixture (ACM) in feeding growing camelsis economically efficient for meat production with no adverse effects onquantity and quality meat characteristics.