DIETARY FAT TYPE ALTER PERFORMANCE AND QUALITY OF MEAT IN MALE BROILER

Transcription

1 DIETARY FAT TYPE ALTER PERFORMANCE AND QUALITY OF MEAT IN MALE BROILER S. Chekani-Azar 1, Parviz Farhoomand 2, Habib Aghdam Shahryar 1 1 Department of Animal Science, Islamic Azad University, Shabestar Branch, Shabestar 2 Department of Animal Sciences Urmia University, Urmia, Iran Abstract The aim of this study was to investigate the effects of 3% dietary fat compositeness two type of source in different levels of poultry fat (PF) and fish oil (FO) to be replacement on performance, cholesterol (CHOL) and triglyceride (TG) contents and sensory quality of male broiler meat after withdrawal of FO from diets. Birds in completely randomized design at four treatments with 4 replicates fed experimental diets includes (T1= 3% PF, T2= 2% PF+1% FO, T3= 1% PF+2% FO, and T4=3% FO) and were given ad libitum to the birds throughout the growth period. At 42 days, the Performance parameters were calculated and also, CHOL, TG contents and organoleptic Characteristics of thigh and breast meats were determined after withdrawal of FO from the diet in 49 days. Altering dietary Fat Type with replacing PF by FO resulted in performance improvement of birds. The male broilers fed 1% PO + 2% FO (T3) presented better values of feed efficiency and weight gain. The CHOL and TG contents only in thigh muscle were significantly decreased. By the sensory evaluations tests detected that the meat of T3 was acceptable. Therefore, Altering Fat Type from PF to FO in diet of male broiler resulted in better performance and produce salutary product without significant sensory losses which may improve nutritional content and promote of human health. Key Words: Fish oil, Poultry fat, Chol & TG, sensory quality, Broiler meat Introduction It has been observed frequently that replacing fish oil, source type of rich in LC n-3 PUFAs such as EPA and DHA, in dietary fat is effective on performance improvement, decrease of CHOL and TG contents of body and play important roles in human health (Crespo and Esteve-Garcia, and Abas et al., 2004). On the other hands, The chicken has been considered an appropriate model in lipid nutrition studies, since it is quite sensitive to fat type and dietary modifications and many of the studies done with chickens deal with the degree of saturation or source type of the dietary replaced fat and how it influences the performance and carcass quality improvement of the animal (Rymer and Givens, 2005,). Nowaday, chicken a type of meat of great consumption, not only the amount but also the quality of its body fat has a great importance for the producers and the consumers. For this reason, currently the industry tries to produce chickens with a good quality and lower CHOL and TG contents of meat, and the ability of the animals to modify and to deposit the omega-3 fatty acids that receive through the diet is being studied (Wongsuthavas et al., 2007). The objective of present study was to assess the effects of Altering dietary Fat Type with replacing PF by FO on performance, cholesterol and triglyceride contents and sensory quality of thigh and breast tissues of male broilers. Materials and Methods Six hundred 1 day-old ROSS-308 unsexed chicks obtained from Samin Hatchery Co., Maragheh, Iran, were reared with commercial feed starter from 1-20 d. At 21st days, 240 male chickens were sexed, individually weighed and randomly placed in 16 floor pens of meters with 15 birds per pen and were fed the experimental diets which were formulated isonitrogenous (19.5% CP) and isoenergetic (3136 kcal kg -1 ME), in accordance with the NRC-1994., and including 3% PF (T1), 2% PF + 1% FO (T2), 1% PF + 2% FO (T3) and 3% FO (T4) during 21 days growth period. The diets and fresh water were offered ad libitum. Ingredient composition and nutrient calculation for diets are shown in Table 1. Fish oil and poultry fat supplied with collaborator of Mehregan- Khazar Co., Bandar-Abbas, Iran. This oils stored in dark station at 4 C until to mixing with diet. At 42-days, the performance parameters were calculated and the birds were slaughtered at 49 days (two samples per pen) after 539

2 540 2 nd Mediterraean Summit of WPSA withdrawal of FO from diet to determinate parameters. After evisceration of birds, they were apportioned by hand into commercial cuts and total breasts and thighs, with the skin on, were placed in plastics bags and refrigerated (-6 C) during transport to the laboratory. At the laboratory, the samples were frozen a -20 C for two month (Lo pez-ferrer et al., 1999). All the cutted samples with a blade cutter were mixed to obtain a homogenous mixture. Total lipids from tissues were extracted by standard procedures following homogenization in suitable excess of chloroform/methanol (2: 1) according to folch et al. (1957) method. After compietion of extraction process, four-microliters aliquots from ready sample were injected in commercial kit (kone commercial kit, japan), and The CHOL and TG were analysed by means of Autoanalyser (ALCYON-300, Autoanalyser, American). The sensory analysis of the samples of chicken breasts and thighs were conducted following Lo pez-ferrer at al (1999). However, the water-holding capacity (juiciness) and tenderness, calculated following Grashorn (1995) and Seemann (1985), respectively. Data collected were subjected to analysis of variance, and where significant differences were observed, means were further subjected to Duncan s multiple range tests, the statistical analysis system (SAS Institute, 2000). The results were considered as significant when p values were less than The data are expressed as means and their standard errors (SE). Results From The performance parameters, final body weight and daily weight gain were increased and feed conversion ratio (FCR) was significantly decreased as dietary fat type altered from PF to FO. Feed intake was not shown different between treatments. The better results in significant parameters achieved for T3 (1% PF + 2% FO). Cholesterol and triglyceride concentrations were determined in thigh and breast muscles of birds fed at the different substitution levels of dietary fat (Table 3). CHOL and TG contents were significantly influenced by the dietary fatty acid profile only in thigh muscle. However, in both thigh and breast, diets of rich in fish oil caused lower values in compared to dietary PF (T1) or mixed with 1% FO (T2) which diluted the LC n-3 PUFA percentage of the dietary fat. Meat quality parameters of thighs and breast meats are shown in Table 4. Different amounts of FO in dietary fat indicated significant difference in normal smell of meat. The thighs and breast of birds of T4 had least normal smell but, the flavour, juiciness and tenderness of meat in birds fed from 3% fish oil (T4) non-significantly increased. Discussion The present results related to performance improvement of male broilers confirm the effects observed by Zollitsch et al. (1997) Abas et al. (2004). They have reported that digestibility of fat increase as the degree of unsaturation increase. Crespo et al. (2001) found lower the catabolic response induced by immune stimulation by increasing fish oil levels in diet that effectively may promote growth. The our findings for CHOL and TG contents are in agreement with other observations by Crespo and Esteve-Garsia (2003), who founds lower levels of CHOL and TG contents in tissues for birds fed n-3 PUFA-rich diets. They reported that the n-3 PUFA content reduced the very low density lipoprotein (VLDL) levels in blood. This effect is because of acting to lower the circulating free low density lipoprotein (LDL) concentration which is normally delivered to tissues for fat storage or is deposited directly in the arteries, and reduces the rate of TG synthesis in the liver. In particular, the intake of PUFA compared to the intake of SFA, causes a lower fat deposition in the animal (Skrivan et al., 2005). Therefore, fish oils reduce the absorption of dietary CHOL and TG and Fish oils rich in EPA and DHA is very effective. The results of the sensory quality evaluations were showed that adding vitamin E to experimental and withdrawal plan diets and also, withdrawal of FO from the diet in the last week, concealed the distasteful odors and improved of flavour, juiciness and tenderness of meat of birds fed from FO. However, normal smell was significant, especially in meat samples of T4, but scores of the all samples containing FO were higher (above 3 scores). Moreover, the all sensory quality observations related to T2 and T3 samples were voted to acceptableness of those that could be related to composition type of dietary fat (fish oil mixed with poultry fat). Meat rich in PUFA is highly susceptible to oxidative processes, which may harm human health. By considering important influence of EPA and DHA on performance improvement, reduce of CHOL and TG contents of tissues and also, omega-3 enrichment of meat (Chekani-Azar et al. 2008), it is recommended that ensuring adequate stability of the diet with antioxidant such as vitamin E in broiler diets - relatively high levels can be fed- is

3 necessary (Surai and Sparks, 2000). Otherwise, EPA and DHA contents and those s effects in meat could be limited and off-flavors could occur. Scientists, researchers and poultry producers should combine their efforts in order to provide nutritionally improved products. Because, the produce of enriched and salutary product without unacceptable odors which play important role in promote of human health, is one of the main aims of nutrition and Physiology specialists. Conclusion In conclusion, Altering dietary Fat Type with replacing PF by FO induced a significant weight gain, decreases of CHOL and TG contents in tissues of male broilers, and these results indicate that diets containing FO are beneficial for the growth performances and for the carcass quality Improvement of male broilers. Acknowledgments This study was supported in part by Islamic Azad University Research Science Shabestar Branch. We would like to thank Prof. Dr. K. Nazer-Adl for directing to us with his experiences in research. The authors are also grateful to Dr. N. Maheri-Sis for his valuable support and to Dr. A. Ahmadzaadeh and Dr. A. M. Vatankhah for their skilled technical assistance throughout the experimental analyses. References ABAS, I., H. ÖZPINAR, R. KAHRAMAN, H.C. KUTAY, H. ESECELİ and M.A. Grashorn., (2004): Effect of dietary fat sources and their levels on performance of broilers, Archiv für Geflügelkunde, 68: CHEKANİ-AZAR, S., H. A, SHAHRİAR., N, MAHERİ-SİS., A, AHMADZADEH and TOHİD VAHDATPOOR., (2008): Omega-3 Fatty Acids Enrichment and Organoleptic Characteristics of Broiler Meat. Asian J. Anim. and Vet. Adv., 3 (2): CRESPO, N., and ESTEVE-GARCIA, E., (2001): Dietary fatty acid profile modifies abdominal fat deposition in broiler chickens. Poult Sci, 80, CRESPO, N., And Esteve-Garcia, E., (2003): Polyunsaturated fatty acids reduce insulin and very low density lipoprotein levels in broiler chickens. Poultry Sci. 82, GRASHORN, M. A., (1995). Instrumental methods for measuring meat quality features. Pages in: Proceedings of the XII European Symposium on the Quality of Poultry Meat, Zaragoza, Spain. Lo PEZ-FERRER, S., BAUCELLS, M.D., BARROETA, A.C., and GRASHORN, M.A., (1999): N-3 Enrichment of chicken meat using fish oil: alternative substitution with rapeseed and linseed oils. Poult Sci, 78, NATIONAL RESEARCH COUNCIL., (1994): Nutrient Requirements of Poultry. 9th rev. ed. National Academy Press. Washington, DC. RYMER C., and GIVENS D.I., (2005): n-3 fatty acid enrichment of edible tissue of poultry: a review. Lipids 40, SAS Institute., (2000): SAS User s Guide: Statistics. SAS Institute Inc., Cary, NC. SEEMANN, G., Vorschlag eines verbesserten Verfahrens zur Ermittlung sensorischer Unterschiede. Arch.Geflu gelkd. 45: SKRİVAN, M., SKRİVANOVA, V., MAROUNEK, M., TUMOVA, E., and WOLF, J., (2000): Influence of dietary fat source and copper supplementation on broiler performance, fatty acid profile of meat and depot fat, and on cholesterol content in meat. Br. Poultry Sci. 41, SURAI, P. F., and SPARKS, N. H. C., (2000): Tissue-specific fatty acid and α-tocopherol profiles in male chickens depending on dietary tuna oil and vitamin E provision. Poult Sci, 79, WONGSUTHAVAS, S., TERAPUNTUWAT, S., WONGSRİKEAW, W., KATAWATİN, S., YUANGKLANG, C., and BEYNEN, A.C., (2007). Influence of amount and type of dietary fat on deposition, adipocyte count and iodine number of abdominal fat in broiler chickens. J. Anim Physiol. Animal Nutr., (E-publication ahead of print). ZOLLİTSCH, W., KNAUS, W., AICHINGER, F., and LETTNER, F., (1997): Effects of different dietary fat sources on performance and carcass characteristics of broilers. Anim. Feed Sci. Technol, 66,

4 542 2 nd Mediterraean Summit of WPSA Table 1. Composition and calculated nutrient content of diets fed to chicks Ingredients Starter Grower Withdrawal Calculated Starter Grower Withdrawal (%) diet diet 1 Plan diet 2 nutrient content diet diet Plan diet Yellow corn ME (kcal/kg) 2,950 3,136 3,020 Wheat Crude protein (%) Soybean meal Calcium (%) Fish meal Available P P (%) Added PF/FO Methionine (%) Monocalcium phosphate Met+Cys (%) Dicalcium phosphate Lysine (%) Bone meal Oyster shell DL-Methionine Salt Vitamin/mineral premix Coccidiostat Vit E Vit A Total T1, control diet = 3% poultry fat (PF); T2 = 1% fish oil (FO) + 2% PF; T3 = 2% FO + 1% PF; T4 = 3% FO. 2Oil remove for 1 wk. 3Provides per kilogram of diet: vitamin A, 9,000,000 IU; vitamin D3, 2,000,000 IU; vitamin B1, 1,800 mg; vitamin B2, 6,600 mg; vitamin B3, 10,000 mg; vitamin B6, 3,000 mg; vitamin B12,15 mg; vitamin E, 18,000 mg; vitamin K3, 2,000 mg; vitamin B9, 1,000 mg; vitamin B5, 30,000 mg; vitamin H2, 100 mg; folic acid, 21 mg; nicotinic acid, 65 mg; biotin, 14 mg; choline chloride, 500,000 mg; Mn, 100,000 mg; Zn, 85,000 mg; Fe, 50,000 mg; Cu, 10,000 mg; I, 1,000 mg; Se, 200 mg. Table 2. Performance parameters 1 of birds according to different amounts of fish oil in diets (21 to 42d) Experimental diets 2 Variable T1 T2 T3 T4 SE P 3 Body weight, g (21 days) NS Final body weight g (42 days) d c a b ** Daily weight gain, g / day 61.2 d 63.4 c 66.8 a 65.6 b ** Feed intake, g / day NS FCR, (g feed: g gain) 1.97 a 1.93 b 1.84 d 1.87 c ** a,b,c,d Means in lines with no common superscript are significantly different (P<0.05). 1 Values are means of eight observations per treatment and their standard errors. 2 T1 = diet with 3% PF; T2 = diet with 2% PF + 1% FO; T3 = diet with 1% PF+ 2% FO and T4 = diet with 3% FO. 3 NS= P>0.05; *= P<0.05; **= P<0.01.

5 Table 3. Triglyceride and cholesterol concentrations 1 of thigh and breast tissues of birds fed with experimental diets. 3% fat 2 Thigh tissues Breast tissues Weight Cholesterol Triglyceride weight Cholesterol Triglyceride (g) (mg/100g) (mg/100g) (g) (mg/100g) (mg/100g) T a a a ab T ab a ab a T b ab ab ab T b b b 9.75 b SE P 3 NS * * NS NS NS a,b,c,d Values in the same row and variable with no common superscript differ significantly (P<0.05). 1 Values are means of eight observations per treatment and their standard errors. 2 T1 = diet with 3% poultry fat (PF); T2 = diet with 2% PF+ 1% fish oil (FO); T3 = diet with 1% PF+ 2% FO and T4 = diet with 3% FO; 3 NS= P>0.05; *= P<0.05; **= P< Table 4. Meat quality parameters according to different of fish oil in diets 1 Tissues Thigh Breast Variable 2 T1 T2 T3 T4 SE P 3 T1 T2 T3 T4 SE P 3 Flavour NS NS Normal smell 4.60 a 4.00 b 3.66 b 3.46 b * 4.43 a 4.33 a 3.73 b 3.43 b * Juiciness NS NS Tenderness NS NS a,b,c,d Values in the same row and variable with no common superscript differ significantly (P<0.05). 1 Values are means of fifteen observations per treatment and their standard errors. 2 All above score were subjected 0 to 5. 3 Juiciness = Waterhlding capacity. Proportion of area of liquid in relation to the area of meat. 4 T1 = diet with 3% poultry fat (PF); T2 = diet with 2% PF+ 1% fish oil (FO); T3 = diet with 1% PF+ 2% FO and T4 = diet with 3% FO; 5 NS= P>0.05; *= P<0.05