347
Effects of phytogenic additives on intake, growth performance, carcass characteristics in steers fed high-concentrate diets
The objective of this study was to evaluate the effects of supplementing the diet of feedlot cattle with natural plants extracts on intake, growth performance and carcass characteristics. Were used 114 Nellore steers (333.88±2.43 of initial BW) were assigned to a randomized complete block design with 4 treatments and 5 replicates. Blocks were defined by initial BW and pens (5 or 6 animals) were considered as replicates. Treatments were defined as follows: monensin (TM – control, Rumensin 80, Elanco Animal Health, Indianapolis, IN, 330 mg∙steer−1∙d−1); dry extract of Stryphnodendron adstringens (TS – 15 g∙steer−1∙d−1); commercial product 1 (TP1 - essential oils - commercial dose); and commercial product 2 (TP2 - extract of cashew nut - commercial dose). The composition of the diets was 19.49% of sugarcane bagasse and 80.51% of concentrate compound of corn, soybean meal, urea and minerals. Means were compared using Tukey’s Test (P<0.05). Additives did not influence final BW (kg), ADG (kg/d), dressing percentage, ADG of carcass (kg/d) and fat thickness (mm) (P>0.05). Animals of TM consumed less DM (kg/d) (6.822 - P<0.01) and DMI/BW (%) (1.668 - P<0.01) than others treatments. TM had better FE (kg/kg) than TS and TP1(P<0.01), but was similar to TP2 (P>0.05). In summary, monensin supplementation might be effective in growth performance primarily through reduced DMI of finishing steers.
Table 1. Means and standard error of growth performance and carcass characteristics of finishing steers fed a total mixed ration supplemented with additives monensin (TM), dry extract of Stryphnodendron adstringens (TS), commercial product 1 (TP1) and commercial product 2 (TP2)
Items |
Treatment |
P-value |
|
|||
TM1 |
TS2 |
TP13 |
TP24 |
|
||
Final BW (kg) |
481.65a±17.13 |
484.91a±16.47 |
486.70ª±18.43 |
489.11a±16.62 |
0.60 |
|
DMI (kg/d) |
6.82b±0.29 |
8.02a±0.28 |
7.83ª±0.26 |
7.49ª±0.18 |
<0.01 |
|
DMI/BW (%) |
1.67c±0.02 |
1.96a±0.03 |
1.90ab±0.03 |
1.82b±0.04 |
<0.01 |
|
ADG (kg/d) |
1.39a±0.06 |
1.42a±0.04 |
1.44ª±0.07 |
1.46a±0.05 |
0.52 |
|
FE (kg/kg) |
0.21a±0.01 |
0.18b±0.01 |
0.18b±0.01 |
0.19ab±0.01 |
<0.01 |
|
Dressing percentage |
56.24a±0.46 |
54.97a±1.56 |
56.40a±0.32 |
56.44a±0.38 |
0.55 |
|
ADG of carcass (kg/d) |
1.00a±0.05 |
1.03a±0.04 |
1.04a±0.05 |
1.05a±0.04 |
0.25 |
|
Fat thickness (mm) |
3.14a±0.48 |
2.60a±0.43 |
2.79a±0.39 |
2.82a±0.33 |
0.42 |
|
1Monensin (Rumensin 80, Elanco Animal Health, Indianapolis, IN); 2Dry extract of Stryphnodendron adstringens; 3Commercial product 1; 4Commercial product 2 (extract of cashew nut - commercial dose)
Keywords: feedlot, natural plants extracts, Nellore steers