However, total Lys intake, available Lys intake was increased (Linear, p = 0.01, p = 0.01) as the Lys:calorie ratio increased (Linear, p = 0.01).
For gilts, no difference (p>0.05) was observed on the ADG and ADFI among all treatments, however, the F:G ratio was tend to be increase (Linear, p = 0.08) by the increasing dietary Lys:calorie ratio (Table 3).
However, total Lys intake (barrows, 14.0, 17.0, 17.4 and 19.3 g/d; gilts, 14.3, 16.8, 17.6 and 19.6 g/d) and available Lys intake (barrows, 12.1, 14.7, 15.1and 16.8 g/d; gilts, 12.3, 14.6, 15.3 and 17.1 g/d) were increased (Linear, p = 0.01, p = 0.01) as the dietary Lys:calorie ratio increased.
October 9: Whitland v Beddau Llangennech v Glamorgan Wdrs UWIC v Narberth Bonymaen v Builth Wells Fleur De Lys v Bridgend Athletic Blackwood v Tonmawr Brynmawr v Maesteg
October 16: Narberth v Beddau Carmarthen Ath v Glamorgan Wdrs UWIC v Whitland Maesteg v Fleur De Lys Tonmawr v Builth Wells Bridgend Athletic v Blackwood Brynmawr v Bonymaen
October 20: Narberth v Carmarthen Ath Llangennech v Whitland Bridgend Athletic v Bonymaen Tonmawr v Maesteg Glamorgan Wdrs v Beddau Blackwood v Brynmawr Builth Wells v Fleur De Lys
Table 2 shows the effect of dietary Lys:DE ratio on the growth performance in pigs.
TMV (Technical Model for Pig Nutrition, 1994) model predicted 794, 734 and 658 g daily gain with 358, 332 and 299 g/kg feed efficiency in pigs fed with high, medium, and low Lys:DE diets, respectively.
Previously, both Jenkins and Emmons (1983) and Kanjanapruthipong (1998) reported that supplementing Lys, Met, Thr, and Ile could increase ADG in calves fed MR containing milk and soy proteins.
Compared with gain to feed ratio (0.48) observed in our study, lower or similar gain to feed ratio (0.44) obtained in the abovementioned study (Hill et al., 2008b) with higher dietary CP and EE concentrations demonstrated that adding Lys, Met and Thr to MR not only improved performance, saved protein resources but also minimized the environmental impacts of calves.
The concentrations of serum biochemical parameters such as protein, calcium, phosphorus and cholesterol were not influenced by the variation in Lys contents of the diet (Table 3).
In the present study, at the lowest concentration of Lys (1.1%) and CP (19.0%), BWG was lowest and FCR was poorest.