Broken rice in a fermented total mixed ration improves carcass and marbling quality in fattened beef cattle

Abstract

Objective This study aimed to determine the effects of replacing cassava chips with broken rice in a fermented total mixed ration diet on silage quality, feed intake, ruminal fermentation, growth performance, and carcass characteristics in the final phase of fattening beef cattle. Methods Eighteen Charolais-Thai native crossbred steers (average initial body weight: 609.4±46 kg; average age 31.6 mo) were subjected to three ad libitum dietary regimes and were maintained in individual pens for 90 d before slaughter. The experimental design was a randomized complete block design by initial age and body weight with six replicates. The dietary regimens used different proportions of broken rice (0%, 16%, and 32% [w/w] of dry matter [DM]) instead of cassava chips in a fermented total mixed ration. All dietary treatments were evaluated for in vitro gas production and tested in in vivo feeding trials. Results The in vitro experiments indicated that organic matter from broken rice was significantly more digestible than that from a cassava-based diet (p0.05). However, the marbling score increased, and the carcass characteristics improved with broken rice. Conclusion Substitution of cassava chips with broken rice in beef cattle diets may improve fattened beef carcass quality because broken rice increases rumen fermentation, fatty acid biosynthesis, and metabolic energy supply.

Keywords

• feeding
• growth performances
• marbling
• rice
• ruminant