Protein, nucleic acid content and activity of μ- and m-calpain in thelongissimus dorsimuscle as affected by protein and energy restriction during early growth of pigs

Abstract

The study was conducted to determine the changes in growth rate, protein deposition, concentration of nucleic acids, and activity of calpain enzymes in the longissimus dorsi muscle of pigs, which received a low protein and low energy diet from 25-50 kg bodyweight (BW) followed by adequate feeding to 105 kg BW in comparison with pigs fed adequately throughout the study. The muscle of pigs subjected to limitation tended to grow slower and deposit less protein daily (by 25%, p < 0.10), but have a significantly lower DNA concentration (by 13%, p < 0.01). The activity of micro- and m-calpain was also significantly lower compared with control pigs (0.942 vs. 1.92 and 0.246 vs. 0.403 U/g, respectively). After resumption of adequate feeding, the daily gain of muscle and protein deposition did not differ from control pigs. Moreover, at 80 kg and 105 kg BW the DNA and RNA concentration as well as the activity of m-calpain and micro-calpain did not differ between groups.

Body composition and fatty acid profile of <i>musculus longissimus dorsi</i> in growing pigs fed a diet supplemented with grass meal

“…In the present study the IMF content in the MLD was lower in the pigs fed the GM diet, doubtless due to the lower energy content of the feed. This was also found in a study on pigs (Skiba et al, 2009) and steers (Schoonmaker et al, 2004). Moreover, Scerra et al (2007) showed that feeding ewes with pasture increased the PUFA content in the IMF of their lambs compared with diets consisting of concentrate.…”