Performance, carcass traits, and body composition of broilers fed different linseed oil levels between 21 and 56 days of age

Supplementing flaxseed oil for long periods improved carcass quality and breast fatty acid profile in Japanese quail

The efficient time for supplementing flaxseed oil to meat-type quail to produce n-3 fatty acid fortified meat has not been determined. This study was conducted to find out the effects of different periods of flaxseed oil supplementation in the Japanese quail diet on the subsequent growth performance, carcass characteristics, fatty acids profile of breast, and functional properties of the Japanese quail meat. Totally, 720 one-day-old Japanese quail were studied in a 35-day experiment using a completely randomized design. Substituting sunflower oil with flaxseed oil had no significant effect on weight gain and feed intake in Japanese quails. Supplementing flaxseed oil for the whole 35-day growth period significantly reduced abdominal fat proportion. Flaxseed oil addition to the quail diet just a week before slaughter resulted in a 4.97-fold increase in the n-3 fatty acid content of the breast muscle. Feeding flaxseed oil decreased the activity of delta-9-desaturase in quail's breast compared to sunflower oil. The greatest thrombogenic index observed in the breast meat from control while consumption of flaxseed oil significantly decreased the thrombogenic index. Supplementing flaxseed oil to quail's diet for 21 and 35 days before slaughter significantly increased breast malondialdehyde content. Feeding flaxseed oil for long periods had no significant impact on the breast meat pH while water holding capacity was decreased. The breast lightness was increased when the flaxseed oil was fed for longer periods. Generally, feeding flaxseed oil in the last week of the growth period improved the feed conversion ratio and the fatty acid profile of quail breast meat with the minimum deterioration effects on meat quality characteristics.

Effect of genotypes on macronutrients and antioxidant capacity of chicken breast meat

OBJECTIVE

The increasing consumer awareness of food, which can provide health benefits and potentially aid disease prevention, has become the driving force of the functional food market. Accordingly, the aim of this study was to investigate the effects of chicken genotype on the macronutrient content, bioactive peptide content, and antioxidant capacity within different breast meat.

METHODS

In this experiment, three genotypes of chicken, Thai indigenous, black-boned, and broiler (control), were reared with commercial feed under the same conditions. Thirty chickens were slaughtered at typical market age and the breasts were separated from the carcass to determine macronutrient content using the AOAC method. The antioxidant capacities of the chicken breasts were evaluated by in vitro antioxidant assays and the protein pattern was investigated using gel electrophoresis. Carnosine and anserine, which have antioxidant properties in animal tissue, were determined using high performance liquid chromatography.

RESULTS

The results showed that breast meat from Thai indigenous chickens had a greater macronutrient content and higher antioxidant capacity compared with the other genotypes (p<0.05). The protein pattern was similar between genotypes, however Thai indigenous chickens had the greatest myosin and actin content (p<0.05). In addition, carnosine and anserine values were greatest in the black-boned and Thai indigenous chickens compared with the broiler genotype (p<0.05).

CONCLUSION

Thai indigenous chicken breast meat may be classified as a functional food as it has good nutritional value and is rich in antioxidant peptides.

Impacts of Graded Levels of Metabolizable Energy on Growth Performance and Carcass Characteristics of Slow-Growing Yellow-Feathered Male Chickens

A dose-response study was conducted to investigate the metabolizable energy (ME) requirement for Lingnan chickens from 9 to 15 weeks of age. One thousand two hundred 8-week-old slow-growing yellow-feathered male chickens were allotted to five dietary ME levels (2805, 2897, 2997, 3095 and 3236 kcal/kg). The results revealed that the daily metabolizable energy intake increased (p < 0.01), whereas the feed intake and feed:gain ratio decreased linearly (p < 0.01) with the increment in dietary ME level. The final body weight and daily gain of the highest ME treatment tended (p > 0.05) to be greater than those obtained with the lower ME levels. The fat content in breast muscle showed a quadratic response (p < 0.05) to the increase in dietary energy level. The shear force values of breast muscle in the 2897, 3095 and 3236 kcal/kg treatments were lower (p < 0.05) than those of the 2997 kcal/kg treatment. In conclusion, among the tested ME levels, 3095 kcal/kg was adequate for feed intake, shear force, and plasma uric acid, and 3236 kcal/kg tended to increase the body weight, body gain, and feed conversion ratio of Lingnan males between 9 and 15 weeks of age; further studies are still required for testing higher levels.

A reduced cost strategy for enriching chicken meat with omega-3 long chain polyunsaturated fatty acids using dietary flaxseed oil

1. This study aimed to determine the minimal duration required for feeding male broilers (Cobb 500) with a flaxseed oil diet while still retaining long chain omega-3 polyunsaturated fatty acid (n-3 LCPUFA) accumulation in the meat at a desirable level. 2. Three groups of broilers (60 each) were fed on a 3% flaxseed oil (high α-linolenic acid (ALA)) diet for either 6, 4 or 2 weeks prior to slaughter. During the remaining time they were maintained on a 3% macadamia oil (low ALA) diet. A fourth group (control, n = 60) was fed on a commercial diet for 6 weeks. 3. No significant difference was observed in growth performance of broilers between groups. The amounts of total n-3 and n-3 LCPUFA in breast and thigh meat were not different between broilers fed the flaxseed oil diet for 4 and 6 weeks, but they were lower (P < 0.001) in those fed the flaxseed diet for only 2 weeks. 4. These results suggest comparable levels of n-3 LCPUFA in the meat can be achieved by only feeding the flaxseed oil diet in the last 3-4 weeks of the growth period; this would result in a ≥ 9.4% reduction in the use of flaxseed oil compared to 6 weeks of feeding; thereby reducing the cost of the enrichment process.

Effect of diets with different energy concentrations on growth performance, carcass characteristics and meat chemical composition of broiler chickens in dry tropics

Background

Diets with increasing levels of energy were fed for 42 days to 200, 1-day old male broiler chickens to evaluate growth performance, carcass characteristics and chemical composition of meat. The study was performed in the subtropical area of northeastern Mexico. Treatments diets (T) for starter and finisher phases had apparent metabolizable energy (AME; kcal/kg) of: 2960 and 3040 (T1); 3000 and 3080 (T2); 3040 and 3120 (T3); 3080 and 3160 (T4), respectively. Within each of the growing phases the four treatment diets were formulated to contain similar levels of crude protein, amino acids, and other nutrients. In a completely randomized design, birds were allocated to the four treatments with five replicates (floor pens) of 10 birds each. The trial was divided in two phases (starter and finisher) of 21 days each (42 days total).

Results

Weight gain was not influenced by energy level; however, feed conversion efficiency was improved in the diets with 3040 and 3120 kcal/kg AME (T3; P < 0.05). There was no influence of treatment on total carcass weight or carcass cuts (P > 0.05). Meat from breast muscle had similar crude protein percentages among treatments; ether extract was higher in T1 than T4 (P < 0.05). The percentages of water, ether extract, ash and crude protein in thigh meat were not significantly different (P > 0.05) among treatments.

Conclusions

For this study carried out in a dry tropical area, the moderate increase in dietary energy concentration (diet with 3040 and 3120 kcal/kg AME, T3) enhanced feed conversion efficiency of broiler chickens.