Testing the 65% bioefficacy concept for MHA-FA in slow-growing broilers
In this trial, the replacement of liquid methionine hydroxy analogue (MHA-FA) with DL-methionine (DL-Met) in a 100:65 ratio did not impair the performance of slow-growing broilers. The trial confirmed an earlier meta-analysis concluding that the bioefficacy of 65% for MHA-FA is independent of dietary settings and broiler genetics. Replacing 100% MHA-FA with 65% DL-Met has substantial cost saving potential.
The study showed that the bioefficacy of 65% for MHA-FA relative to DL-methionine can also be applied to slow-growing broiler strains.
Bavarian State Research Center for Agriculture, Kitzingen, Germany
The aim of this study was to apply the 65% bioefficacy concept where MHA-FA is replaced with DL-methionine (DL-Met) in a 100:65 weight ratio in a slow-growing broiler strain.
Location: Bavarian State Research Center for Agriculture, Kitzingen, Germany
Project team leaders: Dr. Philipp Hofmann, Dr. Andreas Lemme
| Animals | 1,000 male Ranger Classic (38.7 g/chick); 40 birds per floor pen, 25 pens |
| Design | 2 x 2 factorial feeding trial plus an additional treatment |
| Housing | Floor pens, 5 m², straw pellets as bedding |
| Diets | Corn, wheat, soybean meal-based diets Treatments 1 and 2 Treatments 3 and 4 Treatment 5 |
| Feeding | Pelleted feed; ad libitum; 2 experimental phases: 18-35 days, 36-46 days; until day 18 commercial feed for all |
| Parameters | Average daily weight gain, feed per gain, breast meat yield |
| Duration | Days 18-46 |
Trial results
- Reduction of methionine supplementation significantly impaired the performance of slow-growing broilers (Figure 1).
- There were no differences between MHA‑FA and DL‑Met treatments at either supplementation level with respect to feed conversion ratio. (Figure 2).
- Breast meat yield did not significantly differ between corresponding 100% MHA-FA : 65% DL‑Met treatments. However, the 65% DL‑Met treatments showed 0.5 to 0.6%-points higher breast meat yield compared to 100% MHA-FA treatments (Figure 3).
- Compared to DL-Met-65% treatments, cost of product intake (Table 1) was 22% higher for MHA-FA. Supplementing MHA-FA at 88%, bioefficacy reduced feed cost by 12% relative to DL‑Met. However, replacement of MHA‑FA by DL‑Met in a 100:65 weight ratio, reduced feed cost by 22 to 23% showing the most economic use of DL‑Met.
