Responses of Cobb×Cobb 500 slow feathering broilers to feeding programs with increasing amino acid densities (original) (raw)
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Response of Two Different Strains of Commercial Broilers to Different Dietary Amino Acid Allowance
Media Peternakan, 2010
The response of Cobb and Ingham strain commercial broilers to a range of dietary amino acids in a factorial experiment (2 strains x 2 sexes x 3 dietary treatments) with 3 replicates was evaluated. A total of 180 birds was sexed and weighed at one-day-old and randomly distributed to 36 brooders. Summit (246 g CP and 16.8 g lysine/kg) and dilution (120 g CP and 6.0 g lysine/kg) diets were prepared in isocaloric at 3100 kcal ME/kg. The estimated dietary level of crude protein for all birds at day-old was 240 g/kg and at 42 days were 120, 140 or 160 g/kg for females or 140, 160 or 180 g/kg for males. Body composition was measured at 42 days. Results revealed that strain Cobb males and females had a higher daily intake than Ingham, but Cobb females were less effi cient in converting feed to weight gain than that of Ingham. The quantitative differences did not exist between genotypes, crude protein and lysine. Daily gain and feed utilization effi ciency in both sexes were highest in group receiving the high protein diet. Lysine requirement was 14.58 g lysine /kg diet and 12.96 g/kg higher than NRC recommendation (1.05 % or 10.5 g/kg) for maximum breast meat and lowest abdominal fat.
Brazilian Journal of Poultry Science, 2004
This study was conducted to evaluate the performance and carcass and breast yields of broilers fed two different energy levels (3,200 or 2,900 kcal ME/kg) and two ways of expressing amino acid requirements (total TAA or digestible DAA) between 21 and 42 days of age. The results showed that broilers fed the diet containing 3,200 kcal ME/kg had higher weight gain (P=0.015), better feed conversion (P=0.001), and higher abdominal fat deposition (P=0.001) as compared to those fed the diet containing 2,900 kcal ME/kg. Diets formulated on DAA basis promoted higher weight gain (P=0.043), better feed conversion (P=0.010) and better conversion of ME intake into weight gain (P=0.007) as compared to those formulated on TAA basis. The results of this study suggest that formulation based on DAA is necessary if the diets contain protein sources that are not reliable in terms of amino acid digestibility. The response to formulation based on DAA was minimized when birds received the low energy level diet (2,900 kcal ME/kg).
Brazilian Journal of Poultry Science, 2003
An experiment was conducted to evaluate the effect of different digestible amino acid profiles on the performance of broilers in two phases: from 1 to 21 days and from 22 to 42 days of age. At the end of the experiment, carcass yield and cut percentages were evaluated. Nine hundred and sixty AgRoss birds were distributed in a randomized block design with four treatments (four digestible amino acid profiles): Rostagno et al. (2000), Baker & Han (1994b), Degussa (1997) and those recommended by AgRoss (2000), with six repetitions and 40 birds per repetition (20 males and 20 females). The results showed that the four diets were able to provide the requirements of the birds, since no significant differences were seen among the treatments on the performance in the two phases and on the carcass yield and cuts at 42 days of age. Males had better yields of feet, head and neck, and lower percentage of abdominal fat (p<0.05). The best cost/benefit ratio was seen for the profile established by Rostagno et al. (2000) when diets were evaluated in an ideal protein situation.
Optimizing the feeding time for low crude protein, amino acid-supplemented diets for broilers
The objectives of this research were to determine whether delaying the feeding of a diet with reduced crude protein, supplemented with L-Lysine, for several days post-hatching, would result in improved growth performance of broiler chicks and determine an optimal time to feed such a diet to the chick. All experiments were conducted in brooder batteries from 0-to 14-or 18-days (d) post-hatching. Treatments contained a minimum of 6 replicate pens with at least 6 broilers per pen. Two experiments were conducted to determine whether delaying the feeding of a corn-soybean meal (SBM) diet with reduced CP for either the first 5 or 10 days post-hatching would result in improved growth performance of broilers. The results of these experiments show that even when the diets are not deficient in amino acids (AA), feed efficiency is negatively affected by switching birds to a low CP diet several days after post-hatching; effects on daily gain are minimal until the diet becomes deficient in AA. Two experiments were conducted to determine the optimal time to feed a diet with reduced CP, supplemented with L-Lysine, to the chick. The results of these experiments indicate that as long as the diets are not deficient in AA, overall growth performance during the starter phase is not negatively affected for broilers switched from diets with reduced CP to one with an adequate level, at day 5 or day 10 posthatching, or those fed the reduced CP diets continuously.
Effect of low protein diets with amino acid supplementation on broiler growth
The Journal of Applied Poultry Research, 2001
Reduction of litter N and ammonia production can be accomplished by decreasing dietary CP to levels below the requirements listed by the National Research Council. However, amino acids must be added to low CP diets to obtain satisfactory growth performance. It is important to know what levels of amino acid supplementation are required in low CP diets to avoid decreased growth performance and feeding excess amounts of expensive ingredients. Two studies were conducted to determine if further supplementation with essential amino acids (EAA) or nonessential amino acids (NEAA) or energy to corn-soybean meal diets low in CP (17.3 or 17.7% CP and already supplemented with multiple essential amino acids) could improve growth of broilers during Weeks 2 and 3. Ten cages of six males were assigned to each of eight treatments per study. In both trials, a high CP diet (22.6 or 23.0%) resulted in higher BW gain and gain to feed ratio (GFR), compared with all other treatments. In Experiment 1, adding Arg, Thr or Trp, but not Ile nor Glu, increased BW gain and feed intake. Supplemental Thr improved GFR. In Experiment 2, supplemental Thr + Trp + Arg was beneficial in the presence of extra energy or NEAA. The results of Experiment 1, but not of Experiment 2, suggest that the low CP diet was not limiting in NEAA but had insufficient Thr.
Kafrelsheikh Veterinary Medical Journal
Two hundred day-old unsexed broiler (Cobb 500) chicks were randomly distributed to four groups. The first (control) group was fed on starter (22% CP, 3100 Kcal/kg ME, 1.10% Lysine, and 0.48% Methionine) and finisher (20% CP, 3200 Kcal/Kg ME, 0.90% Lysine, and 0.35% Methionine) diets. The other three groups were fed on three starter and finisher isocaloric isonitrogenou diets with 2% lower protein content than the diets of control group with addition of graded levels of L-lysine HCl and DL-methionine to give 120%, 140%, and 160% of the NRC (2000), At the end of starting period, the increased Lysine and Methionine content of the low-protein starter's rations didn't affect body weight and gain but increased the feed consumption and decreased the feed conversion ratio of the birds. At the end of finishing period, body weight, body gain, feed intake, and breast meat yield increased significantly with the increasing of synthetic amino acids in the diets, while the best feed conversion ratio was obtained with 120% amino acids level. Plasma uric acid level increased with Effect Of Feeding Low-Protein, L-Lysine And Dl-Methionine-… Gaafar, K et al., 339 feeding broiler on low protein diets and with increasing of synthetic amino acids supplementation to the diets. Plasma Creatinine increased in the birds fed on low-protein diet supplemented with the highest synthetic amino acids level (160%). Plasma Calcium wasn't affected by the treatment while phosphorus increased in the birds fed on low-protein, DL-Methionine and L-lysine supplemented diets compared with the control group, which might be as indicator for enhanced growth of these groups. It could be concluded that the minimum levels of protein (20% and 18% for starting and finishing periods, respectively) in the broiler's diets supplemented with 120% of NRC requirements for Lysine and Methionine requirements ensure an optimum body weights, body gains, and feed conversion ratios with reduced plasma level of Uric acid but were inadequate to produce the highest breast meat yield.
Increasing Amino Acids Density Improves Broiler Live Weight
International Journal of Poultry Science, 2011
This research evaluates amino acid density in two phases throughout life in Arian male broilers to better understand the impact of increase and decrease dietary amino acids density in live weight performance. Four diets with different levels of amino acids density, High (H), Medium (M), Standard (S) and Low (L) were used in a completely randomized experimental design. All diets were isocaloric and isonitrogenous. Broilers fed H diet, body weight in 42 d was increased by 202 g compared with standard group (p<0.05). Levels of amino acids density had a significant effect on body weight in weeks 1, 2, 4, 5 and 6. Feeding broilers with H diet was significant highest in body weight in weeks 4, 5 and 6. H treatment was significant highest daily body weight gain from 22 to 42 (grower phase) and 1 to 42 day of age compared with S treatment (p<0.05). The results of this study suggest that high amino acids density throughout life optimized live weight and growth, whereas reductions in amino acids density reduced growth and live weight.
The Journal of Poultry Science, 2008
An amino acid bioassay was carried out to compare responses of male and female broiler chicks to di erent ideal amino acid (AA) ratios from to d of age. The ideal ratios were used to calculate AA requirements were IICP (Illinois Ideal Chick Protein), NRC (), RPAN (Rhone Poulenc Animal Nutrition) and feedstu AA ratios which were compared with each other and with a positive control diet. Indispensable AAS were rationed to lysine according to requirement ratios in tested profiles, with digestible lysine set at. and. for male and female, respectively. Experimental period began at day and lasted in d of age. Diets for all profiles contained kcal AME /kg, and L-glutamic acid was used to make all diets equal in crude protein at. of the diet. Chicks fed diets formulated with RPAN had significantly lower weight gain and feed e ciency than IICP, NRC and feedstu which is probably consequence of high Lys: Leu ratio in this profile. There were no significant di erences in feed intake, weight gain and feed: gain among chicks fed IICP, NRC () and feedstu. Since IICP ratios in the case of all AAS (except Met Cys in NRC) are lower than or close to the ratios in NRC () and feedstu , it can be concluded that IICP ideal ratios is su cient for supporting maximal weight gain and feed e ciency. Chicks fed diets which their AA requirements calculated by feedstu ratios had higher breast meat yield than IICP and NRC () which may be due to higher Lys: Met Cys ratio in this profile. Results of this experiment suggest that although male and female broiler chicks have di erent body composition and consequently di erent AA requirements, but they respond similarly to di erent ideal AA ratios. : amino acid profile, broiler, ideal protein for Lys is uncomplicated (Baker, ; Emmert and Baker, tios, although amino acid requirements change due to men-the other amino acids), it is a limiting AA in reduced protein corn-soybean meal broiler diets, and the analysis Growing concerns about the environmental impact of animal production may lead to addition of environmental ; Baker and Han,). Most of the works has been factors such as nitrogen and phosphorus pollution as para-done, on ideal AA ratios with young birds from hatching meters in feed formulation schemes in the future. Since to about weeks of age whereas the database for broilers ideal protein (or ideal amino acid) concept provide a pre-from third to sixth weeks of age is still rather limited. cise ratio of AAS and minimizes nitrogen excretion, it can With respect to lack of accurate requirement informations play an integral role in precision nutrition. AA require-for most AAS in the later stages, using ideal ratios for prements can be influenced by a variety of dietary (e.g., pro-dicting AA requirements may be more beneficial. When tein level, energy level, presence of protease inhibitors), birds advance in age (or weight), both AA requirements environmental (e.g., disease, crowding, feeder space, heat and ideal ratios would change with aging. This was asand cold stress) and genetic factors (e.g., sex and capacity sumed primarily because it seemed probable that as birds for lean vs. fat growth). According to ideal amino acid ra-age, maintenance needs for AA such as methionine, cystine, theronine, tryptophan, valine, arginine and isoleucine tioned factors, ideal ratios, unlike to requirements, would would increase faster than maintenance needs for lysine not change. In this concept lysine was chosen as reference (Emmert and Baker,). Maintenance needs as a per-AA and all the other AAS expressed as a percentage of centage of total AA requirements are minimal (probably lysine. Lysine was chosen because it is used almost exclu-to) for young birds, but they increase substantially as sively for protein accretion after absorption (contrary to birds advance in age and weight. However, research using pigs and rats has long led to the belief that the percentage of lysine required for maintenance is very small and does not increase substantially as birds grow and age. Thus the ideal ratios of those amino acids contributing significantly to maintenance (e.g. methionine, cystine, theronine etc)
Brazilian Journal of Poultry Science, 2005
We studied the effects of two different systems of expressing amino acid requirements (total - TAA or digestible - DAA), two energy levels (2,900 or 3,200 kcal of ME/kg) and two physical forms (mash or pellet) on the performance of male broilers from 21 to 42 d of age. Diets formulated on DAA basis improved feed conversion (p<0.001) and the conversion of consumed ME into body weight gain (p<0.001). Birds fed 3,200 kcal ME/kg presented better feed conversion (p<0.001), higher abdominal fat deposition (p<0.001) and worse conversion of consumed ME into body weight gain (p<0.001) as compared to birds fed 2,900 kcal ME/kg. Birds fed pelleted feed had higher feed intake (p<0.001), higher weight gain (p<0.001), better feed conversion (p<0.001), better conversion of consumed ME into body weight gain (p<0.001) and higher abdominal fat deposition (p<0.001). The results obtained in the present study suggest that feed formulation based on DAA is required when diets contain protein sources which amino acid digestibility is unreliable. Besides, pelleted feed improves performance parameters of broilers.