The effects of dietary methionine (Met) at levels above growth requirements and its consequences on muscle composition and meat quality traits have not been widely reported. However, it was hypothesized that a short-term dietary Met supplementation as HMTBA (2-hydroxy-4(methylthio) butanoic acid) in finishing pigs might influence pork quality traits, without impairing growth performance or carcass composition. The present study aimed to determine the effects of dietary HMTBA supplementation at levels largely above total sulfur amino acid requirements in finisher pigs on growth performance, body composition, muscle biochemical properties and meat quality. For that purpose, a total of 45 crossbred ((Large White × Landrace) × Pietrain) female pigs were allotted into 3 dietary treatments: a control diet (CON group), formulated to meet all nutritional requirements; or an HMTBA-supplemented diet with a calculated Met value 3 times (Met3 group, 0.66% Met) or 5 times (Met5 group, 1.10% Met) greater than that in the CON diet. A control diet was fed to all three groups from 70 kg until 14 days before slaughter (at 105 kg), when dietary treatments were offered until slaughter.
Regarding growth performance, average daily gain, daily feed intake and FCR did not differ between dietary treatments. Likewise, carcass composition did not change between dietary groups. As for muscle biochemical composition, Met-supplemented diets did not affect the longissimus muscle’s (LM) water, protein or myoglobin contents, but intramuscular fat content was lower in Met5 pigs than in CON and Met3 pigs. Regarding antioxidant capacity and pork quality traits, pigs fed the Met5 treatment displayed lower TBARS and higher glutathione levels, along with higher ultimate pH and lower drip, lightness and hue in the LM, compared to the CON and Met3 pigs.
In conclusion, extra-dietary methionine improved ham's technological quality in the Met3 and Met5 groups. Thus, over-dosing dietary HMTBA supplementation improved pork quality without impairing growth or carcass traits.
Lebret, B., Batonon-Alavo, D. I., Perruchot, M. H., Mercier, Y., and Gondret, F. "Improving pork quality traits by a short-term dietary hydroxy methionine supplementation at levels above growth requirements in finisher pigs." Meat science 145 (2018): 230-237. https://doi.org/10.1016/j.meatsci.2018.06.040