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Growth performance, carcass traits, meat chemical composition and blood serum metabolites of broiler chicken fed on diets containing flaxseed oil a
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D.C.N. Lopes , E.G. Xavier , V.L. Santos , F.M. Gonçalves , M.A. Anciuti , V.F.B. Roll , c
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F.A.B. Del Pino , J.O. Feijó & A.A.S. Catalan
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School of Veterinary Medicine, Federal University of Pampa, Uruguaiana, Rio Grande do Sul, Brazil b
Animal Science Department, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil c
Graduate Program in Animal Science, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil d
Animal Science Department, Sul-rio-grandense Federal Institute, Pelotas, Rio Grande do Sul, Brazil e
Veterinary Medicine Graduate Program, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil Accepted author version posted online: 10 Sep 2013.Published online: 08 Jan 2014.
To cite this article: D.C.N. Lopes, E.G. Xavier, V.L. Santos, F.M. Gonçalves, M.A. Anciuti, V.F.B. Roll, F.A.B. Del Pino, J.O. Feijó & A.A.S. Catalan (2013) Growth performance, carcass traits, meat chemical composition and blood serum metabolites of broiler chicken fed on diets containing flaxseed oil, British Poultry Science, 54:6, 780-788, DOI: 10.1080/00071668.2013.843161 To link to this article: http://dx.doi.org/10.1080/00071668.2013.843161
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British Poultry Science, 2013 Vol. 54, No. 6, 780–788, http://dx.doi.org/10.1080/00071668.2013.843161
Growth performance, carcass traits, meat chemical composition and blood serum metabolites of broiler chicken fed on diets containing flaxseed oil D.C.N. LOPES, E.G. XAVIER1, V.L. SANTOS2, F.M. GONÇALVES2, M.A. ANCIUTI3, V.F.B. ROLL1, F.A.B. DEL PINO2, J.O. FEIJÓ4 AND A.A.S. CATALAN2
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School of Veterinary Medicine, Federal University of Pampa, Uruguaiana, Rio Grande do Sul, Brazil, 1Animal Science Department, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil, 2Graduate Program in Animal Science, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil, 3Animal Science Department, Sul-rio-grandense Federal Institute, Pelotas, Rio Grande do Sul, Brazil, and 4Veterinary Medicine Graduate Program, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil
Abstract 1. This study evaluated the effects of diets with partial and total substitution of soya bean oil (SO) with flaxseed (linseed) oil (FO) on broiler chicken performance, carcass traits, meat chemical composition and blood serum metabolites. 2. A total of 448 one-d-old Cobb 500 broiler chicken were used. They were allotted among 4 treatments with 8 replications, using a completely randomised design, for 35 d. Four diets were compared: T1 = 100% SO (3%, 1–7 d; 4%, 8–21 d; and 5%, 22–35 d); T2 = 50% SO + 50% FO; T3 = 25% SO + 75% FO and T4 = 100% FO. 3. No significant differences were observed in body weight (BW), body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and blood serum metabolites (total triglycerides, TRI; total cholesterol, CHO; high-density lipoprotein, HDL; low-density lipoprotein, LDL; glucose, GLU; albumin, ALB; globulin, GLO; and total proteins, TPs). Significant effects were observed for TRI, CHO, HDL, GLU, HDL, LDL, ALB and GLO with regard to the day of collection. 4. Carcass traits did not show significant differences for the treatments. No significant differences were observed for breast and drumstick chemical compositions, with the exception of drumstick fat concentration (quadratic effect). 5. In conclusion, the partial or total substitution of SO with FO did not affect growth performance, carcass traits, meat chemical composition or blood serum profile in broiler chicken. Therefore, FO can be an alternative to SO in the diet formulation for broiler chicken.
INTRODUCTION Chicken meat is widely accepted by consumer markets, ranking second in the world due to its more accessible price compared to pork and beef (FAO, 2012). The growth of poultry production is the result of several factors, with the more important being those related to genetic improvements and animal nutrition. The genetic selection of birds destined for meat production results from the evaluation of performance parameters, such
as body weight (BW), feed conversion rate and carcass traits (Gaya et al., 2006). Improved lineages present rapid growth, resulting in increased nutritional requirements. Oils, combined with synthetic amino acids, are important energy sources in the diet formulation for broilers to sustain their high growth rate. The addition of lipid sources to diets is one option that can improve the birds’ performance due to the high energy density and high metabolisable energy of oils, which can also confer better palatability to the feed (Lara et al., 2005).
Correspondence to: D.C.N. Lopes, School of Veterinary Medicine, Federal University of Pampa, 97500-970, Uruguaiana, Rio Grande do Sul, Brazil. E-mail: [email protected] Accepted for publication 18 July 2013.
© 2013 British Poultry Science Ltd
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FLAXSEED OIL IN BROILER DIETS
Several studies have shown that the utilisation of oils rich in polyunsaturated fatty acids (PUFAs), such as sunflower and flaxseed (linseed) oils (FOs), improves broiler performance compared to animal fats and oils rich in monounsaturated fatty acids (e.g. palm and olive) (Crespo and Esteve-Garcia, 2001, 2002; López-Ferrer et al., 2001a). These results can be explained by the increased digestibility of oils and fats that occurs with the increase in the unsaturated grade of fatty acids (Pinchasov and Nir, 1992; Zollitsch et al., 1997). FO use has resulted in abdominal fat reduction in broilers compared to animal fats and oils rich in monounsaturated fatty acids (Crespo and Esteve-Garcia, 2001, 2002; LópezFerrer et al., 2001a) and compared to SO (Murakami et al., 2010) due to the high oxidation capacity of PUFAs (Sanz et al., 2000). FO can affect the growth performance of broilers (Murakami et al., 2010) by its different organoleptic characteristics (Almeida et al., 2009) or by the presence of antinutritional factors in the flax seeds, such as linatine (Alzueta et al., 2003), which can generate a complex with pyridoxine, affecting the animal metabolism dependent on this vitamin (Leeson et al., 2000). The utilisation of diets rich in 3n-PUFAs, such as flaxseed and fish oils, can affect blood serum metabolites, such as triglycerides and total cholesterol (CHO) (Sanz et al., 1999; Celebi and Utlu, 2000; Newman et al., 2002; Safamehr et al., 2008; Viveros et al., 2009; Velasco et al., 2010). Diets rich in PUFAs, mainly 6n-PUFAs and 3n-PUFAs, can reduce triacylglycerol synthesis and fatty acids in liver, decreasing the concentration of plasma triglycerides in the broilers (Sanz et al., 2000). A few studies (Almeida et al., 2009; Murakami et al., 2010) have evaluated the substitution of soya bean oil (SO) by FO. The aim of the present work was to evaluate the effects of the partial and total substitution of SO by FO in broiler diets on the growth performance, carcass traits, meat chemical composition and blood serum metabolites.
MATERIALS AND METHODS The methodology and protocols for this experiment were approved by the Ethics Commission in Animal Experimentation of the Federal University of Pelotas, Rio Grande do Sul, Brazil, under protocol number 7776. Experimental facility, animals and management A total of 448 Cobb 500 broiler chickens were used, with an initial average weight of 45.2 ± 0.12 g; these birds originated from a commercial hatchery and were vaccinated against Marek and Gumboro diseases. Fourteen birds
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were allotted to each cage (120 cm × 120 cm) in a rearing system over a wood shaving floor for up to 35 d. Water and feed were supplied ad libitum during the whole experimental period with nipple waterers (two nipples/cage) and tubular feeders (15 kg capacity), respectively. Gas brooders supplied thermoneutral conditions in accordance with Cobb 500 management guidelines (Cobb-Vantress 500, 2009a). The lighting consisted of 23 h of light and 1 h of dark (0–6 d); 17 h of light and 7 h of dark (7–13 d); 19 h of light and 4 h of dark (14–27 d); and 23 h of light and 1 h of dark (28–35 d). Ventilation was provided by negative air pressure. Experimental design and diets A completely randomised design was used, with the broiler chickens randomly allotted to 32 cages holding a total of 14 birds each, with 8 replications per treatment; the cages constituted the experimental unit. The birds were given 4 experimental diets, formulated accordingly to the nutritional requirements for each rearing phase (prestarter, starter and finisher), following the recommendations of the Cobb 500 lineage handbook (Cobb-Vantress 500, 2009b) and the ingredient composition reported in Rostagno et al. (2005). The diets were formulated to be isocaloric and isoproteic. The following treatments were tested: T1 – diet containing 100% SO (3%, 1–7 d; 4%, 8– 21 d; and 5%, 22–35 d) and 0% FO; T2 – diet containing 50% SO + 50% FO; T3 – diet containing 25% SO + 75% FO; and T4 – diet containing 0% SO and 100% FO. The nutritional composition of the diets is shown in Table 1. The fatty acid composition of the diets is presented in Table 2. Growth performance and carcass traits The chicks and feed leftovers were weighed weekly to determine the BW, feed intake (FI), body weight gain (BWG) and feed conversion ratio (FCR) for each rearing phase. After 35 d, two birds were separated from each replication, with a BW averaging between 5% above or below the average weight of the cage; a sample of 16 chicks per treatment was obtained, and each chick was identified by numbered rings and subjected to an 8-h fast. The birds were individually weighed at the slaughter platform prior to the normal slaughtering procedures (stunning, bleeding, feather removal and evisceration). Beheaded and without feet, the carcasses were weighed after cooling in a chiller. The following cuts were weighed in pairs, with all parts retaining the skin and bones: breast, thigh, drumstick, wing, drumstick wing and back. Edible viscera were also weighed: heart, liver, gizzard and
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Table 1.
Ingredients and nutrient composition (g/kg) of the experimental diets Treatment1 Pre-starter (1–7 d)
Ingredient
0FO
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Maize Soya bean meal (45%) Micro-ingredients2,3 Soya bean oil Flaxseed oil Sodium chloride DL-methionine Di-calcium phosphate Sodium bicarbonate L-lysine-HCl Butylated hydroxytoluene
Starter (8–21 d)
Finisher (22–35 d)
50FO
75FO
100FO
0FO
50FO
75FO
100FO
0FO
50FO
75FO
100FO
562.9 562.9 355.0 355.0 40.0 40.0 30.0 15.0 0.00 15.0 4.0 4.0 2.8 2.8 2.6 2.6 1.5 1.5 1.0 1.0 0.2 0.2
562.9 355.0 40.0 7.5 22.5 4.0 2.8 2.6 1.5 1.0 0.2
562.9 355.0 40.0 0.0 30.0 4.0 2.8 2.6 1.5 1.0 0.2
599.5 310.0 40.0 40.0 0.0 3.5 2.3 1.7 1.5 1.3 0.2
599.5 310.0 40.0 20.0 20.0 3.5 2.3 1.7 1.5 1.3 0.2
599.5 310.0 40.0 10.0 30.0 3.5 2.3 1.7 1.5 1.3 0.2
599.5 310.0 40.0 0.0 40.0 3.5 2.3 1.7 1.5 1.3 0.2
610.0 287.8 40.0 50.0 0.0 3.5 2.3 2.9 1.5 1.8 0.2
610.0 287.8 40.0 25.0 25.0 3.5 2.3 2.9 1.5 1.8 0.2
610.0 287.8 40.0 12.5 37.5 3.5 2.3 2.9 1.5 1.8 0.2
610.0 287.8 40.0 0.0 50.0 3.5 2.3 2.9 1.5 1.8 0.2
183.5 13.30 9.8 7.4 2.0 6.2 9.5 4.6
183.5 183.5 183.5 13.30 13.30 13.30 9.8 9.8 9.8 7.4 7.4 7.4 2.0 2.0 2.0 6.2 6.2 6.2 9.5 9.5 9.5 4.6 4.6 4.6
Calculated nutrient content (g/kg) Crude protein 210.0 210.0 210.0 210.0 Metabolisable energy (MJ/kg) 12.50 12.50 12.50 12.50 Digestible lysine 10.9 10.9 10.9 10.9 Digestible methionine plus cystine 8.5 8.5 8.5 8.5 Digestible tryptophan 2.3 2.3 2.3 2.3 Digestible threonine 7.1 7.1 7.1 7.1 Calcium 10.0 10.0 10.0 10.0 Available phosphorus 5.0 5.0 5.0 5.0
192.6 192.6 192.6 192.6 12.96 12.96 12.96 12.96 10.0 10.0 10.0 10.0 7.7 7.7 7.7 7.7 2.1 2.1 2.1 2.1 6.5 6.5 6.5 6.5 9.7 9.7 9.7 9.7 4.8 4.8 4.8 4.8
0FO = diet with 100% of soya bean oil (SO) and 0% of flaxseed oil (FO); 50FO = diet with 50% of SO + 50% of FO; 75FO = diet with 25% of SO + 75% of FO; 100FO = diet with 0% of SO and 100% of FO. 2 Micro-ingredients (per kg) (pre-starter and starter phases): Ca, 210 g; P, 85.7 g; F, 828 mg; retinol, 75 mg; cholecalciferol, 1.25 mg; dl-tocopheryl acetate, 375 mg; menadione, 42.5 mg; thiamin, 45 mg; riboflavin, 150 mg; pyridoxine, 62.5 mg; cyanocobalamin, 300 µg; niacin, 1000 mg; folic acid, 27 mg; pantothenic acid, 400 mg; choline, 12.5 g; biotin, 2 mg; methionine, 45 g; Mn, 2500 mg; Zn, 1500 mg; Fe, 1250 mg; Cu, 250 mg; I, 15 mg; Se, 8.2 mg. 3 Micro-ingredients (kg) (finisher phase): Ca, 200 g; P, 77 g; F, 710 mg; retinol, 42 mg; cholecalciferol, 1 mg; dl-tocopheryl acetate, 325 mg; menadione, 35 mg; thiamin, 45 mg; riboflavin 125 mg; pyridoxine, 75 mg; cyanocobalamin, 300 µg; niacin, 875 mg; folic acid, 19 mg; pantothenic acid, 300 mg; choline, 7.5 g; methionine, 31 g; Mn, 2500 mg; Zn, 1500 mg; Fe, 1250 mg; Cu, 250 mg; I, 15 mg; Se, 8.2 mg. 1
Table 2.
Analysed fatty acid composition (g/kg fat) of the experimental diets Experimental diets1 Pre-starter
Fatty acid
0FO
C18:2n-6c (linoleic acid) 520.84 C18:3n-3 (linolenic acid) 40.74 C20:2n-6 0.101 C20:3n-6 0.027 C20:3n-3 0.000 C22:2n-6 0.000 522.12 Total 6n-PUFAs2 40.74 Total 3n-PUFAs2 562.86 Total PUFAs2
50FO
75FO
445.95 139.18 0.072 0.031 0.018 0.018 447.16 139.36 586.52
388.66 199.3 0.065 0.019 0.013 0.000 389.15 199.44 588.95
Starter 100FO
0FO
342.83 529.57 234.29 41.41 0.021 0.080 0.027 0.013 0.029 0.000 0.000 0.000 343.32 530.56 234.58 41.41 577.9 571.97
50FO
75FO
427.07 149.09 0.066 0.002 0.000 0.005 427.82 149.09 576.91
372.16 232.41 0.087 0.017 0.026 0.030 373.54 232.67 606.22
Finisher 100FO
0FO
334.66 511.8 268.01 37.28 0.026 0.034 0.003 0.010 0.027 0.000 0.009 0.000 335.05 512.63 268.28 37.28 603.33 549.92
50FO
75FO
100FO
399.72 177.13 0.071 0.018 0.018 0.018 401.98 177.31 579.29
354.8 261.38 0.057 0.009 0.024 0.017 356.53 261.62 618.14
296.7 301.9 0.064 0.009 0.030 0.036 298.2 302.2 600.4
0FO = diet with 100% of soya bean oil (SO) and 0% of flaxseed oil (FO); 50FO = diet with 50% of SO + 50% of FO; 75FO = diet with 25% of SO + 75% of FO; 100FO = diet with 0% of SO and 100% of FO. 2 Polyunsaturated fatty acids (PUFAs). 1
abdominal fat. The carcass yield (CY) was determined relative to the slaughter weight (% CY = [carcass weight × 100]/live weight), and the yield of the cuts (YC) (thigh, drumstick, wing, drumstick wing and back) was determined relative to the carcass weight without the head (% YC = [cut weight × 100]/carcass weight).
Blood serum metabolites To evaluate the blood serum metabolites, the blood from 8 chickens/treatment (1 chicken/cage) was collected. The same birds, which were identified with rings, were used for the blood collection at 21, 28 and 34 d of age. The birds were in the postprandial state. The blood collections were performed
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by puncturing the brachial vein using disposable syringes with 20 × 100 mm metallic needles in vacuum tubes containing anticoagulants to obtain blood serum. The blood samples were processed and analysed at the Clinic Biochemical Laboratory of Federal University of Pelotas, and the following serum metabolites were assessed: albumin (ALB), total protein (TP), globulin (GLO), CHO, total triglycerides (TRI), high-density lipoprotein (HDL), low-density lipoprotein (LDL) and glucose (GLU). The total GLO were obtained by calculating the difference between the TP and ALB. To determine LDL, the Friedewald et al. (1972) equation was used, where LDL = CHO – (HDL + very low-density lipoprotein [VLDL]), with VLDL = TRI/5; also utilised in research with other avian species (Peebles et al., 1997; Shang et al., 2010). Specific kits (Labtest Diagnostica SA, Minas Gerais, Brazil) were utilised in the analyses for each evaluated blood serum metabolite (cholesterol, HDL, GLU PAP Liquiform, ALB, triglycerides Liquiform, TPs). Meat chemical composition To assess the meat chemical composition, 5 birds/ treatment were selected at random. Then, the breasts and drumsticks (without skin) were defrosted in a refrigerator for 24 h at 4°C. Fresh samples were triturated and then subjected to predrying under forced air at 55°C for 72 h. Afterwards, the samples were ground to perform the analyses of the dry matter (DM), crude protein (CP) and ash (AS), following the methodology recommended by the AOAC (2000). To determine the total lipids (TL), meat samples were triturated and homogenised (Turrax type MA 102, Marconi, Brazil), and the extraction followed the procedure of Bligh and Dyer (1959) and a chloroform:methanol mixture (2:1). For the meat cholesterol assessment, samples of breast and drumsticks (without skin) were defrosted, triturated and homogenised (Turrax type MA 102, Marconi, Brazil) until a non-saponaceous paste matter was obtained through the direct saponification of the samples, according to Saldanha et al. (2004). A specific kit was used to quantify the cholesterol using enzymatic methodology (Laborlab SA Laboratory, São Paulo, Brazil). Statistical analysis The data were subjected to an analysis of variance for a completely randomised design, using the following model: Yij = µ + Ti + εij , where Yij = observation, µ = population mean, Ti = diet effect (i = 1–4) and εij = residual error. Linear and quadratic effects were determined for the use of FO in the diets. Significant differences were considered for P ≤ 0.05.
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For the blood serum metabolites, repeated measure analysis was performed. The main effect means and double interaction (treatment × day of collection) were obtained, and the means were compared using the LS Means test (P < 0.05). For variance and co-variance matrix modelling, three structures were tested: (1) first-order autoregressive, (2) composed symmetry and (3) unstructured. For variance and co-variance matrix election, the Akaike information criterion was used, and the criterion with the lowest value was selected.
RESULTS Growth performance and carcass traits No significant differences were found for FI, BW, BWG and FCR for the broilers given the different FO concentrations during the entire experimental period (Table 3). The carcass weights, cuts, edible viscera and abdominal fat also did not show significant differences for the treatments (P > 0.05, Table 4). A similar result was observed for the CY, cuts and edible viscera of the broilers given different dietary FO concentrations. Blood serum metabolites Increasing concentrations of FO in the diet did not (P > 0.05) affect serum metabolites (Table 5). Significant differences (P < 0.0001) were observed for CHO, GLU and GLO regarding the day of collection, and reduced concentrations were recorded on d 21, 28 and 34 (Table 5). The HDL concentrations were higher (P < 0.0001, Table 5) on d 28 and 34 compared to d 21. For LDL and TRI, the lowest values were obtained on d 34. For ALB, d 21 and 28 did not differ, and the values on both of those days were lower than that recorded on d 34 (Table 5). An interaction between the treatment and the day of collection (P = 0.017, Table 5) occurred only for the GLU concentration. Higher GLU concentrations were observed on d 21 for all treatments, and the GLU concentrations did not differ for the 50–75% FO treatments on d 28. The lowest GLU concentration was observed at 28 d for the 0–100% FO treatments, with the lowest concentration being observed for the 100% FO treatment. After 34 d of treatment, the 0% FO treatment showed a higher concentration of GLU than the other treatments, but there was no significant difference between the 75–100% FO treatments. Meat chemical composition No significant differences (P > 0.05) were observed for the breast and drumstick chemical composition with the increased FO in the diet, except for the
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Table 3.
Growth performance of broiler chickens (1–35 d) fed with 0%, 50%, 75% and 100% flaxseed oil (FO) Treatment1
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Feed intake (g) 1–7 d 8–21 d 22–35 d 1–35 d Live weight (g) 7d 21 d 35 d Body weight gain (g) 1–7 d 8–21 d 22–35 d 1–35 d Feed conversion ratio (g/g) 1–7 d 8–21 d 22–35 d 1–35 d
P-value
0FO
50FO
75FO
100FO
SEM
Linear
152.7 1107 2010 3254
160.5 1131 1996 3288
154.8 1146 2027 3329
155.7 1127 1980 3263
9.75 80.61 80.10 142.6
0.70 0.29 0.65 0.62
0.47 0.35 0.72 0.44
177.6 1009 2182
183.2 1041 2217
180.9 1030 2250
178.9 1020 2164
13.36 56.95 92.85
0.74 0.62 0.94
0.20 0.15 0.38
131.9 832.1 1181 2137
138.2 859.5 1174 2172
135.7 850.2 1219 2205
133.7 841.5 1144 2119
13.27 45.85 92.83 92.83
0.68 0.61 0.78 0.93
0.16 0.15 0.63 0.38
0.07 0.09 0.06 0.05
0.99 0.66 0.80 0.73
0.55 0.75 0.57 0.29
1.16 1.33 1.70 1.52
1.16 1.31 1.70 1.51
1.14 1.35 1.66 1.51
1.17 1.34 1.73 1.54
Quadratic
0FO = diet with 100% of soya bean oil (SO) and 0% of flaxseed oil (FO); 50FO = diet with 50% of SO + 50% of FO; 75FO = diet with 25% of SO + 75% of FO; 100FO = diet with 0% of SO and 100% of FO.
1
Table 4.
Carcass traits of broiler chickens (1–35 d) fed with 0%, 50%, 75% and 100% flaxseed oil (FO) Treatment1
Carcass traits Slaughter weight (g) Carcass weight (g) Breast weight (g) Thigh weight (g) Drumstick weight (g) Back weight (g) Wing weight (g) Drumstick wing weight (g) Heart weight (g) Liver weight (g) Gizzard weight (g) Abdominal fat weight (g) Carcass yield (%) Breast yield (%) Thigh yield (%) Drumstick yield (%) Back yield (%) Wing yield (%) Drumstick wing yield (%) Heart yield (%) Liver yield (%) Gizzard yield (%)
P-value
0FO
50FO
75FO
100FO
SE
Linear
Quadratic
2187 1765 591.5 237.6 276.3 396.2 86.00 89.12 10.01 36.44 51.25 29.67 80.70 33.49 13.48 15.63 22.45 4.90 5.04 0.57 2.08 2.92
2213 1799 610.8 244.2 275.6 410.5 88.00 87.62 11.32 38.31 52.03 26.28 81.26 33.92 13.57 15.31 22.82 4.89 4.87 0.63 2.13 2.89
2234 1818 628.7 238.0 278.5 399.2 88.25 92.00 11.65 41.09 49.97 30.32 81.37 34.55 13.10 15.33 21.95 4.85 5.06 0.64 2.27 2.76
2160 1766 569.0 242.6 271.3 404.6 86.62 87.75 10.30 36.59 50.86 27.57 81.76 32.19 13.74 15.37 22.95 4.90 4.97 0.58 2.08 2.89
104.31 93.80 48.23 19.57 32.87 31.26 5.46 8.20 2.14 5.29 5.75 8.53 15.71 1.69 0.98 1.63 1.51 0.19 0.39 0.12 0.33 0.36
0.88 0.75 0.88 0.56 0.54 0.58 0.58 0.98 0.65 0.70 0.58 0.75 0.14 0.68 0.88 0.21 0.82 0.72 0.83 0.63 0.73 0.58
0.34 0.31 0.36 0.80 0.54 0.63 0.14 0.86 0.21 0.47 0.85 0.83 0.88 0.38 0.69 0.11 0.82 0.72 0.71 0.18 0.56 0.71
0FO = diet with 100% of soya bean oil (SO) and 0% of flaxseed oil (FO); 50FO = diet with 50% of SO + 50% of FO; 75FO = diet with 25% of SO + 75% of FO; 100FO = diet with 0% of SO and 100% of FO.
1
drumstick fat concentration (Table 6). For that variable, a quadratic effect (P = 0.016) was observed, where the maximum fat value was reached with 55.3% of the SO substituted with FO in the diet. Thereafter, a reduction occurred until reaching the 100% substitution concentration.
DISCUSSION Growth performance and carcass traits The results obtained demonstrate that the partial or total substitution of SO with FO did not affect the growth performance of broilers when this oil
FLAXSEED OIL IN BROILER DIETS
Table 5.
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Blood serum metabolites of broiler chickens (1–35 d) fed with 0%, 50%, 75% and 100% flaxseed oil (FO) Blood serum metabolite 2
1
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Treatment (T)
0FO 50FO 75FO 100FO Collection d (D) 21 28 34 T*D 0 × 21 0 × 28 0 × 34 50 × 21 50 × 28 50 × 34 75 × 21 75 × 28 75 × 34 100 × 21 100 × 28 100 × 34
2
2
CHO (mg/dl)
HDL (mg/dl)
LDL (mg/dl)
TRI2 (mg/dl)
GLU2 (mg/dl)
ALB2 (g/dl)
TP2 (g/ dl)
121.5 119.0 122.0 117.4
51.51 52.95 56.83 51.55
47.73 47.38 42.44 54.69
108.9 104.2 105.3 95.3
219.1 214.8 218.0 201.3
1.54 1.59 1.59 1.54
3.09 3.06 3.03 3.20
1.55 1.47 1.43 1.66
136.2 A 123.7 B 100.1 C
61.45 A 47.34 B 50.84 B
55.43 A 57.21 A 31.55 B
105.4 A 110.9 A 94.03 B
233.2 A 210.8 B 195.8 C
1.51 A 1.48 A 1.71 B
3.18 3.02 3.09
1.67 A 1.53 B 1.38 C
137.5 125.2 101.8 134.8 124.5 97.82 138.9 126.8 100.3 133.7 118.2 100.4
60.68 47.43 46.41 61.37 44.13 53.36 64.09 53.18 53.21 59.67 44.61 50.36
52.89 56.71 33.59 54.76 57.22 30.13 51.41 47.57 28.35 62.63 67.35 34.09
107.6 118.0 101.0 107.6 113.7 91.45 108.4 110.3 97.29 98.14 101.5 86.28
236.0 215.7 205.5 232.7 217.7 193.9 241.6 225.5 186.8 222.5 184.3 197.1
1.53 1.44 1.67 1.50 1.50 1.76 1.51 1.55 1.72 1.49 1.44 1.71
3.20 3.02 3.06 3.17 2.96 3.05 3.19 2.87 3.01 3.15 3.21 3.25
1.67 1.58 1.39 1.67 1.46 1.29 1.68 1.32 1.30 1.66 1.77 1.54
British Poultry Science Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/cbps20
Growth performance, carcass traits, meat chemical composition and blood serum metabolites of broiler chicken fed on diets containing flaxseed oil a
b
c
c
d
b
D.C.N. Lopes , E.G. Xavier , V.L. Santos , F.M. Gonçalves , M.A. Anciuti , V.F.B. Roll , c
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F.A.B. Del Pino , J.O. Feijó & A.A.S. Catalan
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School of Veterinary Medicine, Federal University of Pampa, Uruguaiana, Rio Grande do Sul, Brazil b
Animal Science Department, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil c
Graduate Program in Animal Science, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil d
Animal Science Department, Sul-rio-grandense Federal Institute, Pelotas, Rio Grande do Sul, Brazil e
Veterinary Medicine Graduate Program, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil Accepted author version posted online: 10 Sep 2013.Published online: 08 Jan 2014.
To cite this article: D.C.N. Lopes, E.G. Xavier, V.L. Santos, F.M. Gonçalves, M.A. Anciuti, V.F.B. Roll, F.A.B. Del Pino, J.O. Feijó & A.A.S. Catalan (2013) Growth performance, carcass traits, meat chemical composition and blood serum metabolites of broiler chicken fed on diets containing flaxseed oil, British Poultry Science, 54:6, 780-788, DOI: 10.1080/00071668.2013.843161 To link to this article: http://dx.doi.org/10.1080/00071668.2013.843161
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British Poultry Science, 2013 Vol. 54, No. 6, 780–788, http://dx.doi.org/10.1080/00071668.2013.843161
Growth performance, carcass traits, meat chemical composition and blood serum metabolites of broiler chicken fed on diets containing flaxseed oil D.C.N. LOPES, E.G. XAVIER1, V.L. SANTOS2, F.M. GONÇALVES2, M.A. ANCIUTI3, V.F.B. ROLL1, F.A.B. DEL PINO2, J.O. FEIJÓ4 AND A.A.S. CATALAN2
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School of Veterinary Medicine, Federal University of Pampa, Uruguaiana, Rio Grande do Sul, Brazil, 1Animal Science Department, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil, 2Graduate Program in Animal Science, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil, 3Animal Science Department, Sul-rio-grandense Federal Institute, Pelotas, Rio Grande do Sul, Brazil, and 4Veterinary Medicine Graduate Program, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil
Abstract 1. This study evaluated the effects of diets with partial and total substitution of soya bean oil (SO) with flaxseed (linseed) oil (FO) on broiler chicken performance, carcass traits, meat chemical composition and blood serum metabolites. 2. A total of 448 one-d-old Cobb 500 broiler chicken were used. They were allotted among 4 treatments with 8 replications, using a completely randomised design, for 35 d. Four diets were compared: T1 = 100% SO (3%, 1–7 d; 4%, 8–21 d; and 5%, 22–35 d); T2 = 50% SO + 50% FO; T3 = 25% SO + 75% FO and T4 = 100% FO. 3. No significant differences were observed in body weight (BW), body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and blood serum metabolites (total triglycerides, TRI; total cholesterol, CHO; high-density lipoprotein, HDL; low-density lipoprotein, LDL; glucose, GLU; albumin, ALB; globulin, GLO; and total proteins, TPs). Significant effects were observed for TRI, CHO, HDL, GLU, HDL, LDL, ALB and GLO with regard to the day of collection. 4. Carcass traits did not show significant differences for the treatments. No significant differences were observed for breast and drumstick chemical compositions, with the exception of drumstick fat concentration (quadratic effect). 5. In conclusion, the partial or total substitution of SO with FO did not affect growth performance, carcass traits, meat chemical composition or blood serum profile in broiler chicken. Therefore, FO can be an alternative to SO in the diet formulation for broiler chicken.
INTRODUCTION Chicken meat is widely accepted by consumer markets, ranking second in the world due to its more accessible price compared to pork and beef (FAO, 2012). The growth of poultry production is the result of several factors, with the more important being those related to genetic improvements and animal nutrition. The genetic selection of birds destined for meat production results from the evaluation of performance parameters, such
as body weight (BW), feed conversion rate and carcass traits (Gaya et al., 2006). Improved lineages present rapid growth, resulting in increased nutritional requirements. Oils, combined with synthetic amino acids, are important energy sources in the diet formulation for broilers to sustain their high growth rate. The addition of lipid sources to diets is one option that can improve the birds’ performance due to the high energy density and high metabolisable energy of oils, which can also confer better palatability to the feed (Lara et al., 2005).
Correspondence to: D.C.N. Lopes, School of Veterinary Medicine, Federal University of Pampa, 97500-970, Uruguaiana, Rio Grande do Sul, Brazil. E-mail: [email protected] Accepted for publication 18 July 2013.
© 2013 British Poultry Science Ltd
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FLAXSEED OIL IN BROILER DIETS
Several studies have shown that the utilisation of oils rich in polyunsaturated fatty acids (PUFAs), such as sunflower and flaxseed (linseed) oils (FOs), improves broiler performance compared to animal fats and oils rich in monounsaturated fatty acids (e.g. palm and olive) (Crespo and Esteve-Garcia, 2001, 2002; López-Ferrer et al., 2001a). These results can be explained by the increased digestibility of oils and fats that occurs with the increase in the unsaturated grade of fatty acids (Pinchasov and Nir, 1992; Zollitsch et al., 1997). FO use has resulted in abdominal fat reduction in broilers compared to animal fats and oils rich in monounsaturated fatty acids (Crespo and Esteve-Garcia, 2001, 2002; LópezFerrer et al., 2001a) and compared to SO (Murakami et al., 2010) due to the high oxidation capacity of PUFAs (Sanz et al., 2000). FO can affect the growth performance of broilers (Murakami et al., 2010) by its different organoleptic characteristics (Almeida et al., 2009) or by the presence of antinutritional factors in the flax seeds, such as linatine (Alzueta et al., 2003), which can generate a complex with pyridoxine, affecting the animal metabolism dependent on this vitamin (Leeson et al., 2000). The utilisation of diets rich in 3n-PUFAs, such as flaxseed and fish oils, can affect blood serum metabolites, such as triglycerides and total cholesterol (CHO) (Sanz et al., 1999; Celebi and Utlu, 2000; Newman et al., 2002; Safamehr et al., 2008; Viveros et al., 2009; Velasco et al., 2010). Diets rich in PUFAs, mainly 6n-PUFAs and 3n-PUFAs, can reduce triacylglycerol synthesis and fatty acids in liver, decreasing the concentration of plasma triglycerides in the broilers (Sanz et al., 2000). A few studies (Almeida et al., 2009; Murakami et al., 2010) have evaluated the substitution of soya bean oil (SO) by FO. The aim of the present work was to evaluate the effects of the partial and total substitution of SO by FO in broiler diets on the growth performance, carcass traits, meat chemical composition and blood serum metabolites.
MATERIALS AND METHODS The methodology and protocols for this experiment were approved by the Ethics Commission in Animal Experimentation of the Federal University of Pelotas, Rio Grande do Sul, Brazil, under protocol number 7776. Experimental facility, animals and management A total of 448 Cobb 500 broiler chickens were used, with an initial average weight of 45.2 ± 0.12 g; these birds originated from a commercial hatchery and were vaccinated against Marek and Gumboro diseases. Fourteen birds
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were allotted to each cage (120 cm × 120 cm) in a rearing system over a wood shaving floor for up to 35 d. Water and feed were supplied ad libitum during the whole experimental period with nipple waterers (two nipples/cage) and tubular feeders (15 kg capacity), respectively. Gas brooders supplied thermoneutral conditions in accordance with Cobb 500 management guidelines (Cobb-Vantress 500, 2009a). The lighting consisted of 23 h of light and 1 h of dark (0–6 d); 17 h of light and 7 h of dark (7–13 d); 19 h of light and 4 h of dark (14–27 d); and 23 h of light and 1 h of dark (28–35 d). Ventilation was provided by negative air pressure. Experimental design and diets A completely randomised design was used, with the broiler chickens randomly allotted to 32 cages holding a total of 14 birds each, with 8 replications per treatment; the cages constituted the experimental unit. The birds were given 4 experimental diets, formulated accordingly to the nutritional requirements for each rearing phase (prestarter, starter and finisher), following the recommendations of the Cobb 500 lineage handbook (Cobb-Vantress 500, 2009b) and the ingredient composition reported in Rostagno et al. (2005). The diets were formulated to be isocaloric and isoproteic. The following treatments were tested: T1 – diet containing 100% SO (3%, 1–7 d; 4%, 8– 21 d; and 5%, 22–35 d) and 0% FO; T2 – diet containing 50% SO + 50% FO; T3 – diet containing 25% SO + 75% FO; and T4 – diet containing 0% SO and 100% FO. The nutritional composition of the diets is shown in Table 1. The fatty acid composition of the diets is presented in Table 2. Growth performance and carcass traits The chicks and feed leftovers were weighed weekly to determine the BW, feed intake (FI), body weight gain (BWG) and feed conversion ratio (FCR) for each rearing phase. After 35 d, two birds were separated from each replication, with a BW averaging between 5% above or below the average weight of the cage; a sample of 16 chicks per treatment was obtained, and each chick was identified by numbered rings and subjected to an 8-h fast. The birds were individually weighed at the slaughter platform prior to the normal slaughtering procedures (stunning, bleeding, feather removal and evisceration). Beheaded and without feet, the carcasses were weighed after cooling in a chiller. The following cuts were weighed in pairs, with all parts retaining the skin and bones: breast, thigh, drumstick, wing, drumstick wing and back. Edible viscera were also weighed: heart, liver, gizzard and
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Table 1.
Ingredients and nutrient composition (g/kg) of the experimental diets Treatment1 Pre-starter (1–7 d)
Ingredient
0FO
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Maize Soya bean meal (45%) Micro-ingredients2,3 Soya bean oil Flaxseed oil Sodium chloride DL-methionine Di-calcium phosphate Sodium bicarbonate L-lysine-HCl Butylated hydroxytoluene
Starter (8–21 d)
Finisher (22–35 d)
50FO
75FO
100FO
0FO
50FO
75FO
100FO
0FO
50FO
75FO
100FO
562.9 562.9 355.0 355.0 40.0 40.0 30.0 15.0 0.00 15.0 4.0 4.0 2.8 2.8 2.6 2.6 1.5 1.5 1.0 1.0 0.2 0.2
562.9 355.0 40.0 7.5 22.5 4.0 2.8 2.6 1.5 1.0 0.2
562.9 355.0 40.0 0.0 30.0 4.0 2.8 2.6 1.5 1.0 0.2
599.5 310.0 40.0 40.0 0.0 3.5 2.3 1.7 1.5 1.3 0.2
599.5 310.0 40.0 20.0 20.0 3.5 2.3 1.7 1.5 1.3 0.2
599.5 310.0 40.0 10.0 30.0 3.5 2.3 1.7 1.5 1.3 0.2
599.5 310.0 40.0 0.0 40.0 3.5 2.3 1.7 1.5 1.3 0.2
610.0 287.8 40.0 50.0 0.0 3.5 2.3 2.9 1.5 1.8 0.2
610.0 287.8 40.0 25.0 25.0 3.5 2.3 2.9 1.5 1.8 0.2
610.0 287.8 40.0 12.5 37.5 3.5 2.3 2.9 1.5 1.8 0.2
610.0 287.8 40.0 0.0 50.0 3.5 2.3 2.9 1.5 1.8 0.2
183.5 13.30 9.8 7.4 2.0 6.2 9.5 4.6
183.5 183.5 183.5 13.30 13.30 13.30 9.8 9.8 9.8 7.4 7.4 7.4 2.0 2.0 2.0 6.2 6.2 6.2 9.5 9.5 9.5 4.6 4.6 4.6
Calculated nutrient content (g/kg) Crude protein 210.0 210.0 210.0 210.0 Metabolisable energy (MJ/kg) 12.50 12.50 12.50 12.50 Digestible lysine 10.9 10.9 10.9 10.9 Digestible methionine plus cystine 8.5 8.5 8.5 8.5 Digestible tryptophan 2.3 2.3 2.3 2.3 Digestible threonine 7.1 7.1 7.1 7.1 Calcium 10.0 10.0 10.0 10.0 Available phosphorus 5.0 5.0 5.0 5.0
192.6 192.6 192.6 192.6 12.96 12.96 12.96 12.96 10.0 10.0 10.0 10.0 7.7 7.7 7.7 7.7 2.1 2.1 2.1 2.1 6.5 6.5 6.5 6.5 9.7 9.7 9.7 9.7 4.8 4.8 4.8 4.8
0FO = diet with 100% of soya bean oil (SO) and 0% of flaxseed oil (FO); 50FO = diet with 50% of SO + 50% of FO; 75FO = diet with 25% of SO + 75% of FO; 100FO = diet with 0% of SO and 100% of FO. 2 Micro-ingredients (per kg) (pre-starter and starter phases): Ca, 210 g; P, 85.7 g; F, 828 mg; retinol, 75 mg; cholecalciferol, 1.25 mg; dl-tocopheryl acetate, 375 mg; menadione, 42.5 mg; thiamin, 45 mg; riboflavin, 150 mg; pyridoxine, 62.5 mg; cyanocobalamin, 300 µg; niacin, 1000 mg; folic acid, 27 mg; pantothenic acid, 400 mg; choline, 12.5 g; biotin, 2 mg; methionine, 45 g; Mn, 2500 mg; Zn, 1500 mg; Fe, 1250 mg; Cu, 250 mg; I, 15 mg; Se, 8.2 mg. 3 Micro-ingredients (kg) (finisher phase): Ca, 200 g; P, 77 g; F, 710 mg; retinol, 42 mg; cholecalciferol, 1 mg; dl-tocopheryl acetate, 325 mg; menadione, 35 mg; thiamin, 45 mg; riboflavin 125 mg; pyridoxine, 75 mg; cyanocobalamin, 300 µg; niacin, 875 mg; folic acid, 19 mg; pantothenic acid, 300 mg; choline, 7.5 g; methionine, 31 g; Mn, 2500 mg; Zn, 1500 mg; Fe, 1250 mg; Cu, 250 mg; I, 15 mg; Se, 8.2 mg. 1
Table 2.
Analysed fatty acid composition (g/kg fat) of the experimental diets Experimental diets1 Pre-starter
Fatty acid
0FO
C18:2n-6c (linoleic acid) 520.84 C18:3n-3 (linolenic acid) 40.74 C20:2n-6 0.101 C20:3n-6 0.027 C20:3n-3 0.000 C22:2n-6 0.000 522.12 Total 6n-PUFAs2 40.74 Total 3n-PUFAs2 562.86 Total PUFAs2
50FO
75FO
445.95 139.18 0.072 0.031 0.018 0.018 447.16 139.36 586.52
388.66 199.3 0.065 0.019 0.013 0.000 389.15 199.44 588.95
Starter 100FO
0FO
342.83 529.57 234.29 41.41 0.021 0.080 0.027 0.013 0.029 0.000 0.000 0.000 343.32 530.56 234.58 41.41 577.9 571.97
50FO
75FO
427.07 149.09 0.066 0.002 0.000 0.005 427.82 149.09 576.91
372.16 232.41 0.087 0.017 0.026 0.030 373.54 232.67 606.22
Finisher 100FO
0FO
334.66 511.8 268.01 37.28 0.026 0.034 0.003 0.010 0.027 0.000 0.009 0.000 335.05 512.63 268.28 37.28 603.33 549.92
50FO
75FO
100FO
399.72 177.13 0.071 0.018 0.018 0.018 401.98 177.31 579.29
354.8 261.38 0.057 0.009 0.024 0.017 356.53 261.62 618.14
296.7 301.9 0.064 0.009 0.030 0.036 298.2 302.2 600.4
0FO = diet with 100% of soya bean oil (SO) and 0% of flaxseed oil (FO); 50FO = diet with 50% of SO + 50% of FO; 75FO = diet with 25% of SO + 75% of FO; 100FO = diet with 0% of SO and 100% of FO. 2 Polyunsaturated fatty acids (PUFAs). 1
abdominal fat. The carcass yield (CY) was determined relative to the slaughter weight (% CY = [carcass weight × 100]/live weight), and the yield of the cuts (YC) (thigh, drumstick, wing, drumstick wing and back) was determined relative to the carcass weight without the head (% YC = [cut weight × 100]/carcass weight).
Blood serum metabolites To evaluate the blood serum metabolites, the blood from 8 chickens/treatment (1 chicken/cage) was collected. The same birds, which were identified with rings, were used for the blood collection at 21, 28 and 34 d of age. The birds were in the postprandial state. The blood collections were performed
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by puncturing the brachial vein using disposable syringes with 20 × 100 mm metallic needles in vacuum tubes containing anticoagulants to obtain blood serum. The blood samples were processed and analysed at the Clinic Biochemical Laboratory of Federal University of Pelotas, and the following serum metabolites were assessed: albumin (ALB), total protein (TP), globulin (GLO), CHO, total triglycerides (TRI), high-density lipoprotein (HDL), low-density lipoprotein (LDL) and glucose (GLU). The total GLO were obtained by calculating the difference between the TP and ALB. To determine LDL, the Friedewald et al. (1972) equation was used, where LDL = CHO – (HDL + very low-density lipoprotein [VLDL]), with VLDL = TRI/5; also utilised in research with other avian species (Peebles et al., 1997; Shang et al., 2010). Specific kits (Labtest Diagnostica SA, Minas Gerais, Brazil) were utilised in the analyses for each evaluated blood serum metabolite (cholesterol, HDL, GLU PAP Liquiform, ALB, triglycerides Liquiform, TPs). Meat chemical composition To assess the meat chemical composition, 5 birds/ treatment were selected at random. Then, the breasts and drumsticks (without skin) were defrosted in a refrigerator for 24 h at 4°C. Fresh samples were triturated and then subjected to predrying under forced air at 55°C for 72 h. Afterwards, the samples were ground to perform the analyses of the dry matter (DM), crude protein (CP) and ash (AS), following the methodology recommended by the AOAC (2000). To determine the total lipids (TL), meat samples were triturated and homogenised (Turrax type MA 102, Marconi, Brazil), and the extraction followed the procedure of Bligh and Dyer (1959) and a chloroform:methanol mixture (2:1). For the meat cholesterol assessment, samples of breast and drumsticks (without skin) were defrosted, triturated and homogenised (Turrax type MA 102, Marconi, Brazil) until a non-saponaceous paste matter was obtained through the direct saponification of the samples, according to Saldanha et al. (2004). A specific kit was used to quantify the cholesterol using enzymatic methodology (Laborlab SA Laboratory, São Paulo, Brazil). Statistical analysis The data were subjected to an analysis of variance for a completely randomised design, using the following model: Yij = µ + Ti + εij , where Yij = observation, µ = population mean, Ti = diet effect (i = 1–4) and εij = residual error. Linear and quadratic effects were determined for the use of FO in the diets. Significant differences were considered for P ≤ 0.05.
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For the blood serum metabolites, repeated measure analysis was performed. The main effect means and double interaction (treatment × day of collection) were obtained, and the means were compared using the LS Means test (P < 0.05). For variance and co-variance matrix modelling, three structures were tested: (1) first-order autoregressive, (2) composed symmetry and (3) unstructured. For variance and co-variance matrix election, the Akaike information criterion was used, and the criterion with the lowest value was selected.
RESULTS Growth performance and carcass traits No significant differences were found for FI, BW, BWG and FCR for the broilers given the different FO concentrations during the entire experimental period (Table 3). The carcass weights, cuts, edible viscera and abdominal fat also did not show significant differences for the treatments (P > 0.05, Table 4). A similar result was observed for the CY, cuts and edible viscera of the broilers given different dietary FO concentrations. Blood serum metabolites Increasing concentrations of FO in the diet did not (P > 0.05) affect serum metabolites (Table 5). Significant differences (P < 0.0001) were observed for CHO, GLU and GLO regarding the day of collection, and reduced concentrations were recorded on d 21, 28 and 34 (Table 5). The HDL concentrations were higher (P < 0.0001, Table 5) on d 28 and 34 compared to d 21. For LDL and TRI, the lowest values were obtained on d 34. For ALB, d 21 and 28 did not differ, and the values on both of those days were lower than that recorded on d 34 (Table 5). An interaction between the treatment and the day of collection (P = 0.017, Table 5) occurred only for the GLU concentration. Higher GLU concentrations were observed on d 21 for all treatments, and the GLU concentrations did not differ for the 50–75% FO treatments on d 28. The lowest GLU concentration was observed at 28 d for the 0–100% FO treatments, with the lowest concentration being observed for the 100% FO treatment. After 34 d of treatment, the 0% FO treatment showed a higher concentration of GLU than the other treatments, but there was no significant difference between the 75–100% FO treatments. Meat chemical composition No significant differences (P > 0.05) were observed for the breast and drumstick chemical composition with the increased FO in the diet, except for the
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Table 3.
Growth performance of broiler chickens (1–35 d) fed with 0%, 50%, 75% and 100% flaxseed oil (FO) Treatment1
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Feed intake (g) 1–7 d 8–21 d 22–35 d 1–35 d Live weight (g) 7d 21 d 35 d Body weight gain (g) 1–7 d 8–21 d 22–35 d 1–35 d Feed conversion ratio (g/g) 1–7 d 8–21 d 22–35 d 1–35 d
P-value
0FO
50FO
75FO
100FO
SEM
Linear
152.7 1107 2010 3254
160.5 1131 1996 3288
154.8 1146 2027 3329
155.7 1127 1980 3263
9.75 80.61 80.10 142.6
0.70 0.29 0.65 0.62
0.47 0.35 0.72 0.44
177.6 1009 2182
183.2 1041 2217
180.9 1030 2250
178.9 1020 2164
13.36 56.95 92.85
0.74 0.62 0.94
0.20 0.15 0.38
131.9 832.1 1181 2137
138.2 859.5 1174 2172
135.7 850.2 1219 2205
133.7 841.5 1144 2119
13.27 45.85 92.83 92.83
0.68 0.61 0.78 0.93
0.16 0.15 0.63 0.38
0.07 0.09 0.06 0.05
0.99 0.66 0.80 0.73
0.55 0.75 0.57 0.29
1.16 1.33 1.70 1.52
1.16 1.31 1.70 1.51
1.14 1.35 1.66 1.51
1.17 1.34 1.73 1.54
Quadratic
0FO = diet with 100% of soya bean oil (SO) and 0% of flaxseed oil (FO); 50FO = diet with 50% of SO + 50% of FO; 75FO = diet with 25% of SO + 75% of FO; 100FO = diet with 0% of SO and 100% of FO.
1
Table 4.
Carcass traits of broiler chickens (1–35 d) fed with 0%, 50%, 75% and 100% flaxseed oil (FO) Treatment1
Carcass traits Slaughter weight (g) Carcass weight (g) Breast weight (g) Thigh weight (g) Drumstick weight (g) Back weight (g) Wing weight (g) Drumstick wing weight (g) Heart weight (g) Liver weight (g) Gizzard weight (g) Abdominal fat weight (g) Carcass yield (%) Breast yield (%) Thigh yield (%) Drumstick yield (%) Back yield (%) Wing yield (%) Drumstick wing yield (%) Heart yield (%) Liver yield (%) Gizzard yield (%)
P-value
0FO
50FO
75FO
100FO
SE
Linear
Quadratic
2187 1765 591.5 237.6 276.3 396.2 86.00 89.12 10.01 36.44 51.25 29.67 80.70 33.49 13.48 15.63 22.45 4.90 5.04 0.57 2.08 2.92
2213 1799 610.8 244.2 275.6 410.5 88.00 87.62 11.32 38.31 52.03 26.28 81.26 33.92 13.57 15.31 22.82 4.89 4.87 0.63 2.13 2.89
2234 1818 628.7 238.0 278.5 399.2 88.25 92.00 11.65 41.09 49.97 30.32 81.37 34.55 13.10 15.33 21.95 4.85 5.06 0.64 2.27 2.76
2160 1766 569.0 242.6 271.3 404.6 86.62 87.75 10.30 36.59 50.86 27.57 81.76 32.19 13.74 15.37 22.95 4.90 4.97 0.58 2.08 2.89
104.31 93.80 48.23 19.57 32.87 31.26 5.46 8.20 2.14 5.29 5.75 8.53 15.71 1.69 0.98 1.63 1.51 0.19 0.39 0.12 0.33 0.36
0.88 0.75 0.88 0.56 0.54 0.58 0.58 0.98 0.65 0.70 0.58 0.75 0.14 0.68 0.88 0.21 0.82 0.72 0.83 0.63 0.73 0.58
0.34 0.31 0.36 0.80 0.54 0.63 0.14 0.86 0.21 0.47 0.85 0.83 0.88 0.38 0.69 0.11 0.82 0.72 0.71 0.18 0.56 0.71
0FO = diet with 100% of soya bean oil (SO) and 0% of flaxseed oil (FO); 50FO = diet with 50% of SO + 50% of FO; 75FO = diet with 25% of SO + 75% of FO; 100FO = diet with 0% of SO and 100% of FO.
1
drumstick fat concentration (Table 6). For that variable, a quadratic effect (P = 0.016) was observed, where the maximum fat value was reached with 55.3% of the SO substituted with FO in the diet. Thereafter, a reduction occurred until reaching the 100% substitution concentration.
DISCUSSION Growth performance and carcass traits The results obtained demonstrate that the partial or total substitution of SO with FO did not affect the growth performance of broilers when this oil
FLAXSEED OIL IN BROILER DIETS
Table 5.
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Blood serum metabolites of broiler chickens (1–35 d) fed with 0%, 50%, 75% and 100% flaxseed oil (FO) Blood serum metabolite 2
1
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Treatment (T)
0FO 50FO 75FO 100FO Collection d (D) 21 28 34 T*D 0 × 21 0 × 28 0 × 34 50 × 21 50 × 28 50 × 34 75 × 21 75 × 28 75 × 34 100 × 21 100 × 28 100 × 34
2
2
CHO (mg/dl)
HDL (mg/dl)
LDL (mg/dl)
TRI2 (mg/dl)
GLU2 (mg/dl)
ALB2 (g/dl)
TP2 (g/ dl)
121.5 119.0 122.0 117.4
51.51 52.95 56.83 51.55
47.73 47.38 42.44 54.69
108.9 104.2 105.3 95.3
219.1 214.8 218.0 201.3
1.54 1.59 1.59 1.54
3.09 3.06 3.03 3.20
1.55 1.47 1.43 1.66
136.2 A 123.7 B 100.1 C
61.45 A 47.34 B 50.84 B
55.43 A 57.21 A 31.55 B
105.4 A 110.9 A 94.03 B
233.2 A 210.8 B 195.8 C
1.51 A 1.48 A 1.71 B
3.18 3.02 3.09
1.67 A 1.53 B 1.38 C
137.5 125.2 101.8 134.8 124.5 97.82 138.9 126.8 100.3 133.7 118.2 100.4
60.68 47.43 46.41 61.37 44.13 53.36 64.09 53.18 53.21 59.67 44.61 50.36
52.89 56.71 33.59 54.76 57.22 30.13 51.41 47.57 28.35 62.63 67.35 34.09
107.6 118.0 101.0 107.6 113.7 91.45 108.4 110.3 97.29 98.14 101.5 86.28
236.0 215.7 205.5 232.7 217.7 193.9 241.6 225.5 186.8 222.5 184.3 197.1
1.53 1.44 1.67 1.50 1.50 1.76 1.51 1.55 1.72 1.49 1.44 1.71
3.20 3.02 3.06 3.17 2.96 3.05 3.19 2.87 3.01 3.15 3.21 3.25
1.67 1.58 1.39 1.67 1.46 1.29 1.68 1.32 1.30 1.66 1.77 1.54
