Effect of Dietary Crude Protein and Amino Acid Contents on Growth Performance and Carcass Characteristics in Korean Native Ducks

An experiment was conducted to find out the effect of different levels of crude protein in broiler diets during different phases. i.e., pre starter (0-11d), starter (12-21d) and finisher (22-42d). 360 day-old broilers (Vencobb) were procured from a commercial hatchery and fed either high or low dietary CP diets during pre-starter (23 and 21%) , starter (21 and 19%) and high, moderate or low CP diets during finisher ( 18.5, 17.5 and 16.5%) phases, for a total of 12 possible treatment combinations at d 42. The results showed that the broilers fed low levels of CP ( 21 and 19 %) had significantly(P less than 0.05) higher body weight gain (BWG) and feed intake (FI), and better feed efficiency over the diets with high levels of CP during pre-starter and starter phases (23 and 21%, respectively). The higher (18.5%) level of protein in the finisher phase showed higher BWG and best FCR compared to the lower levels (17.5 and 16.5%). Carcass characters were not influenced by the variation in dietary CP level tested except the abdominal fat weight which was significantly higher in broiler fed low CP diet compared to those fed higher levels of CP during all three phases. The results indicated that the broilers fed low CP diets supplemented with critical amino acids (21 and 19%) had beneficial effect on the growth performance during pre-starter and starter phase. The broilers showed an ability to respond to increase in dietary CP levels during finisher phase.

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Effect of reduced dietary crude protein and supplemental limiting amino acids on the growth and carcass characteristics of Swarnadhara chicks

Indian Journal of Animal Research ◽

10.18805/ijar.b-3417 ◽

2018 ◽

Author(s):

Beena C. Joseph ◽

Jayanaik T. Munegowda ◽

Chandrapal . ◽

K. Singh ◽

V. Malathi

Keyword(s):

Amino Acids ◽

Growth Performance ◽

Crude Protein ◽

Control Diet ◽

Carcass Characteristics ◽

Feed Conversion ◽

Breast Meat ◽

Dietary Crude Protein ◽

Carcass Parameters ◽

Limiting Amino Acids

A six-week trial was conducted to determine the effect of lowering dietary crude protein levels with supplementation of limiting amino acid on growth performance, and carcass characteristics in one of the Indian improved crossbred Swarnadhara chicks in a completely randomized design having five treatments and four replications of 20 birds in each. Five isocaloric (2800 ME Kcal//kg) experimental diets based on corn-soy bean meal were formulated in a gradual crude protein decline from 21 % (control T1) to 19% by 0.5% interval. The levels of limiting amino acids namely methionine, lysine, threonine and tryptophan were met as that of control (T1) by adding synthetic preparations. Highest body weight was recorded in 2% crude protein reduced group (T5) which was comparable with control (T1). However, cumulative feed intake and feed conversion ratio of different treatments were not significantly different. Moreover, carcass parameters like dressing percentage, breast meat yield, liver and heart weights remained unaffected by the dietary treatments. Relative gizzard weight and abdominal fat weights showed variations and lower dietary protein diets were comparable with control diet (T1). In summary, crude protein content of Swarnadhara chick diet can be reduced to 19% with essential AA fortification without any adverse effect on growth performance and carcass characteristics during 0-6 weeks of age.

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Evaluation of dietary crude protein concentrations, fishmeal, and sorghum inclusions in broiler chickens offered wheat-based diet via Box-Behnken response surface design

PLoS ONE ◽

10.1371/journal.pone.0260285 ◽

2021 ◽

Vol 16 (11) ◽

pp. e0260285

Author(s):

Shemil P. Macelline ◽

Peter V. Chrystal ◽

Shiva Greenhalgh ◽

Mehdi Toghyani ◽

Peter H. Selle ◽

...

Keyword(s):

Weight Gain ◽

Amino Acid ◽

Growth Performance ◽

Feed Intake ◽

Broiler Chickens ◽

Crude Protein ◽

Surface Design ◽

Dietary Crude Protein ◽

Nutrient Utilisation ◽

Amino Acid Concentrations

The objective of this study was to investigate the impacts of dietary crude protein (CP), fishmeal and sorghum on nutrient utilisation, digestibility coefficients and disappearance rates of starch and protein, amino acid concentrations in systemic plasma and their relevance to growth performance of broiler chickens using the Box-Behnken response surface design. The design consisted of three factors at three levels including dietary CP (190, 210, 230 g/kg), fishmeal (0, 50, 100 g/kg), and sorghum (0, 150, 300 g/kg). A total of 390 male, off-sex Ross 308 chicks were offered experimental diets from 14 to 35 days post-hatch. Growth performance, nutrient utilisation, starch and protein digestibilities and plasma free amino acids were determined. Dietary CP had a negative linear impact on weight gain where the transition from 230 to 190 g/kg CP increased weight gain by 9.43% (1835 versus 2008 g/bird, P = 0.006). Moreover, dietary CP linearly depressed feed intake (r = -0.486. P < 0.001). Fishmeal inclusions had negative linear impacts on weight gain (r = -0.751, P < 0.001) and feed intake (r = -0.495, P < 0.001). There was an interaction between dietary CP and fishmeal for FCR. However, growth performance was not influenced by dietary inclusions of sorghum. Total plasma amino acid concentrations were negatively related to weight gain (r = -0.519, P < 0.0001). The dietary transition from 0 to 100 g/kg fishmeal increased total amino acid concentrations in systemic plasma by 35% (771 versus 1037 μg/mL, P < 0.001). It may be deduced that optimal weight gain (2157 g/bird), optimal feed intake (3330 g/bird) and minimal FCR (1.544) were found in birds offered 190 g/kg CP diets without fishmeal inclusion, irrespective of sorghum inclusions. Both fishmeal and sorghum inclusions did not alter protein and starch digestion rate in broiler chickens; however, moderate reductions in dietary CP could advantage broiler growth performance.

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