وزارة التعليم العالي والبحث العلمي

جامعة بغداد-كلية العلوم

المجلة العراقية للعلوم

عدد خاص- البحوث المقبولة للنشر في 

المؤتمر العلمي الاول- 

قسم علوم الحياة

للفترة من 6-7\ اذار\2012

NUTRIANT VALUE

OF  SOME FRESHWATER FISHES &CLAMS

 FROM IRAQI WATER

*Amer  Al-Shammaa, Muhanned R. Nashaat, Ennas M. Karrim , Lamia A. Rasheed 

[email protected] , Fish Research Center 

The Nutritional valuo (Percentages of moisture, protein, fat and ash and the amount of gross energy) of six young freshwater fishes (10-26cm) brought fromTigris River were studied. These are Barbus grupusالشبوط ; B. sharpeyi البني;Cyprinus carpio L الكارب العادي ; B. xanthopterusالقطان; وHypophthalmichthys molitrix الفضي;and Ctenopharyngdom idellathree species of shellfish (clams محار ) from Al-Habbaniya lakes. They are brought Anadonta sp., Pseudodontpsis eupheraticus and Unio tigridis. The result showed the highest protein content was found in common carp Cyprinus carpio (75.62%) according to the dry weight, and the lowest eupheraticuswas (67.41%) in C. idella. Hoever, it range from 14.93% to 18.16% according to wet weight. For clams, the highest percentage was found in Pseudodontopsis euphraticus L. (58.53%) and the lowest value was in Unio tigridis (52.51%). The percentages of moisture ranged between 73.13% (C.idella) to 79.27% (B.sharpyei.). Ash ranged between 3.54% P.eupheraticu  C. idella to 8.37% (B.grypus) and ether extracts (fat) from 16.1% (C carpio) to 28.64% (C. idella) according to dry weight respectively. Total gross energy of the fish ranged between 557.95 (B. xanthopterus) – P. eupheraticus 631.38 (C. idella) kcal/100g. Whereas, these values were 80.76% (P. eupheraticus) to 82.45% (U. tigridis), 17.88% (U. tigridis) tigridis to 20.21% (P. eupheraticus), 18.81% (P. eupheraticusto 21.72% (U. tigridis) and 486.46 (U. tigridis.o 497.20kcal/100g (Anadonta sp.) for the moisture, ash, fat and gross energy of the clams dry matterswith out the shell, respectively.

 القيمة  الغذائية   لعدد من أسماك ومحار المياه العذبة العراقية

*عامر علي الشماع، مهند رمزي نشأت ، إيناس مجيد كريم  ولمياء عبد الله رشيد 

[email protected] *

مركز الثروة الحيوانية والسمكية، ،  بغداد. العراق.

الخلاصة

     درست القيمة الغذائية ( نسبة الرطوبة والبروتين والدهن والرماد والطاقة الكلية) لستة أنواع من صغار أسماك المياه العذبة  (10-26 سم)  صيدت من نهر دجلة . و شملت أسماك الشبوط Barbusِ grypusِ  والبني B. Sharpeyi والقطان B. xanthopterus والكارب العادي  Cyprinus carpio.  وشملت اسماك الكارب الفضي  Hypophthalmichthys molitrix والكارب العشبي Ctenopharyngdon idella ، التي جلبت من مزرعة أسماك مجاورة، إضافة لثلاثة من أنواع المحار جمعت من بحيرة الحبانية هــي : Pseudodntopsis eupheraticus , Anadonta sp  و Unio tigridis. أتضح من النتائج المحسوبة على أساس وزن السمكة الجاف، ان أعلى نسبة للبروتين الخام كانت لأسماك الكارب العادي  (%75.62)  والأوطأ نسبة  (%67.41)  للكارب العشبي    (Ctenopharyngdon idella )  وكانت نسبة البروتين الخام   بين   %14.93 -%18.16      على أساس الوزن الرطب. أما في المحار فكانت أعلى نسبة للبروتين  الخام  (%58.53) في محار P. eupheraticus وأدنى نسبة له (%52.51)  في الوزن الجاف لمحار Unio tigridis. وكانت نسب الرطوبة تتراوح بيــــن 73.12% للعشبي و 79.27% للبني. وكان الرماد بين 3.54% للعشبي و8.37 % للشبوط، أما نسبة مستخلص الإيثر ( EE /الدهون) فكانت بين 16.1 % للكارب العادي و28.64% للعشبي. وكانت قيمة الطاقة الكلية بين 557.95 kcal/100g في القطان و 631.38kcal/100g في العشبي على التتالي. وتراوحت هذه الكميات بين 80.76 % وP.eupheraticus)- (U.tigridis)%82.45 و17.88%  (.U.tigridis )-20.21  %(P.e.) و18.81 %P.e.)- 21.72 %(U..) وبين 486.46( U. tigridis)  kcal/100g   و(Anadonta.sp.) kcal/100g 497.20 لنسب الرطوبة والرماد والدهون وقيمة الطاقة الكلية لوزن المادة الجافة في المحار دون الصدفة على التتالي

Introduction

     Fishes have a high quality nutritive protein, it contains all the essential amino acids, as well as, number of unsaturated fatty acids. Fish help in decreasing the cholesterol and triglyceriedes level in consumer's blood [1]. Although, the chemical composition of fish often appears to vary from one species and one individual to another depending on environment, seasons, sex and the amount and quality of food that the fish eats. Proteins and fats are the major components whereas carbohydrates are detected at very limited levels (less than 0.5 percent). The study of chemical composition of fish is an important aim for culturing fish of a high nutritive value. Fish meal is considered to be one of the best ingredients for fish, boilers and layers diets, as it enhances the feed consumption and feed efficiency [2]. It rich in lysine and methionine in adequate quantities required for fish culture and poultry [3,4]. Little works were avaliable on chemical composition of different Iraqi freshwater fishes, and almost no information about the nutritive value of shellfish (clams) from Iraqi waters, which, may be used in the feed production for cultured animals. The present work was performed to investigate the nutritive value of six economically important finfish species breaded and consumed in our country, as well as, three shellfish (clams), which may be used in the diet of cultured fish or other farms animals as a source of animals protein. 

Materials and Methods

     Six finfish species Shabott, Barbus grupus  Heckel, Bunni, B. sharpeyi Gunther, Common carp, Cyprinus carpio L., Kattan,B. xanthopterus Heckel, Silver carp Hypophtha-lmichthys molitrix Val. and Grass carp Cteno-pharyngdom idella Val. Ranged from 10cm to 26 cm in lengths were caught from Tigris River, Al-Souara area and three shellfish (clams) species, Anadonta sp., Pseudodontopsis euphraticus and Unio tigridis were collected from Al-Habbaniya lake. Three muscles samples, for each experi-mental group were taken randomly from different fish bodies between caudal  fin and the head (the edible part of the fish ) then mixed and blended together before the proxmate analysis. The same were done to the clams muscles. All proximate analysis, ie, moisture, crude protein (CP), crude fat (ether extracts,EE), ash contents, and the gross energy of both, fish fillets and clams muscles. Muscles were ovens dried at 60°C for 3 days to constant weight, then dry matter were determined on the bases of moisture loss. A 2g. of powdered dry muscle was used for protein content determination by using Kjeldahl apparatus, Crude protein was calculated as Nx6.25. Two grams of the powder was also used for fat content (ether extracts) determination in Soxhlet for about six hours, using petroleum ether (B.P.60°C) for extraction. Ash content was determined by combustion in Furnace at 550 °C for 4hrs [5].The amount of carbohydrate in fish muscles is generally too small to be of any significance in the diet; therefor no values are given in (Table 1). In white fish this amount is usually less than 1%.[6]. The energy value mainly depend on fat content of fish, but if fat and protein content of fish is known, the Gross energy can be roughly calculated according to the equation (CP% × 5.5) + (EE% × 9.1) kcal/100g, (kcal = 4.184 ×  kJ). The values of gross energy were shown in (Table 1). Because no bones and scales with the meat samples; the value of fiber and carbohydrate are negligible[6]. The term fat is used for simplicity throughout this paper, although the less familiar term lipid or ether extracts is more correct, since it includes fats, oils and waxes as well as more complex, naturally-occurring compounds of fatty acids.

Results and Discussion

     The chemical composition of six freshwater fish species and three species of freshwater shellfish (clams) are shown in (Table 1). The result showed that moisture (water) ranged from 73.12% in Grass carp (Ctenophryngdon idella Val.) and 79.27% in Bunni (B. sharpeyi). Water is the main principal components of fish flesh, which usually accounts for about 80% of the weight of a fresh fish fillet. Whereas, the average water content of the flesh of fatty fish is about 70%, but, individual specimens of some fish species may at times be found with water content anywhere between the extremes of 30 and 90% [6].The highest protein (the 2ndprincipal component) content was found in Grass carp, Shabott(B. grypus) and Silver carp 

(Hypophthalmichthys molitrix Val.,) (18.17%), (18.16%) and (17.07%), respectively. Mean-while, Kattan (B. xanthopterus) showed that the lowest percentage of protein (14.93%).                          Although protein content in finfish muscles falls very slightly when the fat content falls, it nevertheless remains fairly constant, somewhere between 15 and 20%. But values lower than 15% or as high as 28% are occasionally met with in some fish species [6].  However, Clams protein contents found to be range from (9.74%) to (11.26%) in wet weight. Murray and Burt[6] showed in their leaflets, that the percentage of crude protein in molluscs (shellfish) ranged from 8.6% to 12.6% in Oyster and from 8.9% to 11.7% in mussels. From the point of view of protein containts, were marked as a rule, that the finfish species have a higher protein percentage comparative to shellfish, (Table 1). Yasser [7] found that the protein content of adult Himrry, (B. luteus) collected from Hor Al-Hammar ranged from 16.27%-22.64% (wet weight) and for Bunni, ranged from 16.01%-22.81%. The adult of Kattan, (B. xanthopterus) from Al-Therthar was found with 17.8% protein [8]. Protein also ranged between 16.41%-22.79% in adult Kattan, and between 14.7%-19.87% for adult Shabott, (B. grypus) from Tigris River (Baghdad) [9]. Similar findings were reported by Al-Aswad et al., [10] for Kattan and Shabott from DukanLake. There is usually considerable seasonal variation in fat content of fatty fish; for example some starved finfish may have as little as 0.5% fat, whereas fish that has been feeding heavily to encourage its growth may have a fat content of over 20% [6]. Fat content in Shabott, Silver carp and Grass carp were (5.22%), (6.68%) and (7.70%) respectively. Whereas, the fat content of the other studied species (fish and clams) were Less than (4.5%) of wet  weight. Al-Habbib  et al.[11] found that the fat content of ten Iraqi fish species was ranging between 0.8% and 6.28%. They considered fish with fat more than 3% of wet weight as a fatty fish. Fat content is one of the most variable body constituents in fishes [12]. Tan, [13] found that Tilapia had a higher fat content than Puntiusgonionotus and Grass carp, However, Yasser, [7] found that the content of protein and fat were related with reproduction cycle. Generally, there is an inverse relationship between fat and moisture content of fish, i.e., as the fat content rises, so the water content falls, and vice versa [1]. The moisture content of the studied species of finfish varied in relationship with fat. Similarly, this relationship between moisture and fat is also not clear in clams, in which fat ranged from 3.62% in (P.e.) to 4.03% in (U.t.) according to the wet weight (Tabl.1). [6]reported that the sum of water and fat in a fatty finfish is fairly constant at about 80%.Whereas, Ash content of the most studied finfish ranged between (0.95%) and (2.17%). Ali [8] observed a reduction in the amount of protein and fat, as well as an increase in moisture and ash in fish body after reproduction. Khatoon et.. al [4] found that ash ranged between 21.03% and 25.71% in commercial fish meal, this meal may be adulterated with cheap diluents such as sand horns and hooves powder [12]. In this work, clams ash contents ranged between (3.32%) and (3.89%). High percentage of ash might be due to the sand and minerals in the stomach of the clams. Chemical composition of finfish is mainly effected by species, sex, season, diet and environment [13-16], and that may be also true for clams. The energy value mainly depended on fat and protein contents of fish, gross energy values were roughly calculated and shown in (Table 1).

Table 1: The chamical comosition of the edible part of finfish and shellfish (clams) according to dry weight %  and the (wet weight %).

M=Moisture, DM= Dry matter; EE=Crude Fat (eather extract); CP=Crude Protein.

* Total length of fish or clam’s shell.

** Gross energy= (CP% × 5.5)+(EE%× 9.1) kcal/100g, (kcal = 4.184 ×  kJ). after  [6&17].