The Lys:calorie ratios discussed in this paper are expressed as total grams of Lys/Mcal DE.
Lys and Threonine composition was measured using an amino acid analyzed (Beckman 6300, Beckman Coulter, Inc., Fullerton, CA, USA) after 24-h 6 N HCl hydrolysis at 110[degrees]C (AOAC, 1995).
The linear, quadratic and cubic effects of Lys:calorie ratio among treatments was analyzed using a contrast statement.
September 25: Builth Wells v Whitland Narberth v Brynmawr Fleur De Lys v Llangennech Carmarthen Ath v Blackwood Beddau v Bonymaen Glamorgan Wdrs v Bridgend Athletic Tonmawr v UWIC
October 2: Whitland v Glamorgan Wdrs UWIC v Carmarthen Ath Llangennech v Beddau Blackwood v Maesteg Brynmawr v Tonmawr Bonymaen v Fleur De Lys Bridgend Athletic v Builth Wells
Therefore, the objective of this experiment was to determine the optimum energy density and Lys:DE ratio for growth performance by analyzing carcass characteristics in finishing barrows.
Barrows were allotted to 1 of 8 dietary treatments with low and high DE and 4 levels of Lys:DE according to a 2x4 factorial arrangement, with 3 replicates for each dietary treatment.
(2008a) observed that starter intake did not change with different Lys or Thr concentrations; but was influenced by Met in the MR with a lower intake associated with 0.68% Met, which is contradictory to our results.
(2007) observed no differences in body condition scores or hip width for calves fed MR varying in Lys or Met.
Four diets were formulated to contain similar ME (2,950 kcal/kg) but contained graded levels of incremental lysine (1.1, 1.2, 1.3 and 1.4%) while also increasing the dietary CP and other EAA (methionine, methionine+cystine, threonine and tryptophan) to maintain a constant ratio with Lys. The concentrations of CP (19.04, 20.77, 22.5 and 24.23%), methionine (0.51, 0.56, 0.61 and 0.66%), methionine+cystine (0.78, 0.85, 0.92 and 0.99%), threonine (0.61, 0.67, 0.72 and 0.78%) and tryptophan (0.17, 0.20, 0.22, 0.23%) were increased progressively with increase in Lys, respectively.
The performance of broilers fed diet containing different concentrations of Lys is presented in Table 2.