Bypass fat enhances liveweight gain and meat quality but not profitability of smallholder cattle fattening systems based on oil palm frond

Abstract

Context Oil palm frond (OPF) is abundantly available throughout Southeast Asia and is a good source of forage for feedlot cattle, particularly during the dry and monsoon seasons when other forage options are limited. However, the use of OPF in ruminants feed is constrained by its complex fibrous structure and low digestibility. Aims The aim of this study was to investigate the impact of supplementation with bypass fat on growth, meat quality and economic returns in smallholder feedlot systems where Napier grass is replaced with OPF. Methods Sixteen Brahman × Charolais crossbred steers, 23 ± 2.0 months old and with initial bodyweight of 425 ± 59.9 kg (mean ± s.e.), were randomly allocated in a 2 × 2 factorial randomised complete-block design experiment with the following dietary treatments: (i) fresh chopped Napier grass-based total mixed ration (TMR; Napier grass–fat), (ii) Napier grass-based TMR + 5% bypass fat (Napier grass+fat), (iii) OPF-based TMR (OPF–fat) and (iv) OPF-based TMR + 5% bypass fat (OPF+fat). Feed intake, digestibility of the diets and average daily gain were measured. The cattle were slaughtered to determine carcass dressing percentage and meat quality. Costs and return of fattening cattle were estimated. Key results Despite higher intake, cattle fed OPF–fat had a lower bodyweight gain than did cattle fed grass-based diets due to lower digestibility. Bypass-fat supplementation increased the bodyweigh of cattle fed OPF but not of cattle fed Napier grass. Fat supplementation enhanced colour, backfat thickness, and fat content of meat in both the Napier grass- and OPF-based diets. However, replacing Napier grass with OPF reduced the net profit of smallholder feedlot systems, even with fat supplementation. Conclusion While fat supplementation increased liveweight gain and enhanced some aspects of meat quality, the increased feeding cost reduced net profit. Therefore, supplementation of OPF with bypass fat is not recommended for smallholder feedlots in developing countries. Implications Appropriate technology to reduce the feeding cost of OPF needs to be developed to make it an economically viable option for smallholder farmers.