Feeding brittle culm1 whole crop rice replacing wheat by-products to growing-finishing pigs

Abstract

The effect of feeding brittle culm1 whole crop rice (WCR) replacing wheat by-products on performance, digestibility and carcass quality was evaluated in growing-finishing pigs. Fifty-four pigs (Duroc) were randomly assigned to three dietary treatments: WCR at levels of 0 (control), 10 or 20%, respectively. Pigs were fed from about 29 to 85 kg. A digestion trial was conducted with all pigs at about 60 kg live weight. When the feeding trial was completed, six pigs from each treatment were slaughtered to determine carcass quality. In the growing period, pigs receiving the 10 or 20% WCR diet were not significantly different in daily feed intake, daily weight gain and feed conversion from the control pigs (p>0.05). In the finishing period, daily feed intake and daily weight gain of pigs fed the 20% WCR diet were significantly lower than control pigs or 10% WCR diet (p<0.05). However, the feed conversion was not significantly different among the pigs on three different diets. No significant (p>0.05) difference was shown in the apparent nutrient digestibility with the WCR substituting for wheat by-products. The dressing percentage and mean backfat thickness tended to be lower in pigs fed the 10 or 20% WCR diet than in control pigs. The meat from pigs on the 20% WCR diet showed a higher pH value at 24 h post mortem, and higher protein and lower fat content in longissimus muscles than control pigs (p<0.05). This study indicated that WCR could be an alternative feed source to replace wheat by-products in growing-finishing pig diets, but a high proportion of the WCR may result in an adverse effect on the performance traits.