Effects of ambient temperature, arginine-to-lysine ratio, and electrolyte balance on performance, carcass, and blood parameters in commercial male turkeys

The effects of ambient temperature (T; 15 C vs. 30 C from 6 wk of age onwar ds), dietary Arg:Lys ratio (Arg:Lys ratio; 1.00 vs. 1.25), dietary electrol yte balance (DEB: 164:vs. 254 meq/kg), and their interactions on growth per formance and carcass yields of male turkeys were studied. The experiment wa s designed as a split plot, including T x DEB as the main plot and Arg:Lys ratio as the sub-plot, with 24 pens containing 35 male turkeys each. Feed c onsumption, BW gain, mortality, and processing yields were measured. Temper ature had a clear effect on performance during all age periods. Feed intake was significantly lower for the high T group compared with the low T group (322.7 vs. 432.3 g/bird per day; P < 0.001). Consequently, BW gain during the experimental period (28 to 140 d of age) was significantly lower for th e high T:group compared with the low T group (14.54 vs. 18.74 kg; P < 0.001 ). Feed:gain during the period of 28 to 140 d of age was significantly lowe r for the high T group compared with the low T group (2.51 vs. 2.61; P < 0. 001). The high dietary Arg:Lys ratio increased feed intake significantly un til 56 d of age (200.6 vs. 197.6; P <less than or equal to> 0.034). A high Arg:Lys ratio resulted in significantly higher BW gain until 98 d of age (1 0.03 vs. 9.84 kg; P less than or equal to 0.024). The Arg:Lys ratio did not affect feed:gain throughout the experiment. Dietary electrolyte balance di d not affect performance parameters. No consistent two- or three-way intera ctions were observed. Processing yields were only affected significantly by T, and not by Arg:Lys ratio or DEB main effects. High T resulted in lower cold carcass (73.2 vs. 74.9%) and breast meat yields (33.5 vs. 36.0%), and higher thigh (18.9 vs. 18.1%), drumstick (14.5 vs. 13.2%), and wing yields (11.7 vs. 10.6%) compared with low T. We concluded that growth performance is compromised by higher T, and altering the Arg:Lys ratio or DEB does not alleviate this impaired performance. Dietary Arg levels seem to be importan t when dietary Lys is marginal relative to the requirement.