Simulación del auditorio

The MEB in this Chapter (and in previous chapter: Chapter 4) revealed defining features of the feed profile and FCE of the grazing system in Sabah that would have been more difficult to assess using other available methodologies. Intuitively, it would have been expected that grazed dry matter would

have been higher than the modelled range of 3.74–7.16 t DM ha–1 yr–1 and closer to the potential of 6.9–

20.6 t DM ha–1 yr–1 identified above (Table 5.2). Conventional techniques for establishing pasture yield

involve either cage cutting over a 12-month period (Radcliffe, 1974, 1975) or dosing animals with a marker such as chromium oxide or n-alkane compound (Carruthers and Bryant, 1983; Oliveira et al., 2007). Both of these methods have high resource demands, significant opportunity for systematic error (Carruthers and Bryant, 1983; Hatfield et al., 1991) and involve cost to purchase the chemicals. By contrast the values obtained by MEB involve a comparatively small resource investment of professional time and modelling, and the errors associated are less than 10% (Nicol and Brookes, 2007), and in this study were assessed at less than 5% (see Section 4.4.1). The methodology also provided unexpected insights, especially with respect to the use of FCE as an indicator for system performance and stocking rate optimisation, which in turn led to a deduction that optimising present systems based on FCE would be a better option than intensification as a first step in system evolution. MEB as a farm systems analysis tool is comparatively unknown in Malaysia. Further, the potential for use in technology transfer is little used in New Zealand, given the tool has been developed through software like Farmax (www.farmax.co.nz) for local system evolution. For these reasons guidelines for organisation of the Sabah data for MEB analysis and for application of New Zealand methodologies to that data had to be

developed de novo. There is a need for a publication to establish a framework for the use of MEB in

farm system technology transfer.

5.5 Conclusions

Based on the data analyses in this chapter, the following conclusion can be made:

x The current average for herbage harvested is 3.74 t DM ha–1 yr–1 across all units (or

subsystems), with the highest value being recorded on any unit being 7.16 t DM ha–1 yr–1. This

is much less than the regional environment potential based on light and rainfall (6.9–20.6 t

x The animal production of the system is also limited by marginal herbage ME and CP values

(7.7–8.5 MJ ME kg DM–1 and 9%–11% CP), similar to the cut-and-carry feedlot system

studied in the previous chapter, with currently about 78% of consumed metabolisable energy being allocated in the system to body maintenance. Part of the limitation is a technical error associated with human judgement on the quantity and quality of herbage and grazing cycle.

x In contrast to temperate pastoral systems, herbage production appears to be aseasonal and

local farm systems could use split calving to avoid a seasonal peak of animal feed demand.

x The PKC use in the system was quantified as 0.47–1.39 t DM ha–1 yr–1 (as herbage

equivalent); thus, some or all PKC use could be eliminated to reduce farm operation cost by targeting improved pasture productivity and quality. If PKC were used, it is targeted tactically to reduce liveweight loss occurrence and enhance mating performance, and to some extent to address the reduction of liveweight loss that currently occurs after weaning. Batches of PKC should be tested before purchase for quality assurance purposes, as some batches purchased

are of low energy value (<9.5 MJ ME kg DM–1), although the CP value is high (16.0%).

x The first step to improve the animal production of the system is to adjust the system

configuration (by using that in 2010 and 2009 as a starting set up) especially stocking rate for optimal FCE. At the current pasture production levels in the system, optimal FCE is achieved

at a stocking rate of approximately 506 kg animal LWT ha–1 or a CSR of approximately 94 kg

LWT t DM–1 offered.

x Following the initial adjustments of system configuration, a second step would be

development of a pasture husbandry package that included guidelines for N application

(including avoidance of alkaloids and oxalate toxicity on Setaria pastures), pasture ME and

CP enhancement, and timing and intensity of grazing management. In the medium term, the feasibility of mitigating the limiting factors to herbage production and quality could be investigated in paddock scale trials and introduced as successful solutions were identified.

Suggested targets for this phase are 14–26 t DM ha–1 yr–1 herbage harvested with ME >9.5 MJ

Chapter 6

Feed Profile Analysis of Oil Palm Integrated Beef Cattle Farming

Systems by Metabolic Energy Budgeting and Implications for Beef

Production and Future System Design in Sabah

Abstract. Metabolic energy budgeting (MEB) was used to model the feed demand patterns of oil palm integrated cattle (OPIC) farming systems in Sabah to gain insight into herbage supply and feed conversion efficiency (FCE) of the system. The animal data used involved 550–800 cattle farmed in three OPIC farms. Two farms were 9 yr old plantations (9OP1 and 9OP2) and one farm was a 12 yr old plantation (12OP). Animal liveweight data available were weights at birth, weaning, 24 months of age, and sale. Liveweight data used to fit growth curves to the supplied weights were obtained from the nearest government farm that had compatible animal growth data to those provided by the farms studied. For additional insight, measurements were also carried out on nutritive value of herbage being grazed, botanical composition, mid- regrowth herbage mass, and pre-grazing herbage mass. (The latter two provided for estimation of herbage accumulation). Results of the MEB indicated that herbage supply as herbage eaten in the system was 2.0–2.4 t DM ha–1 yr–1 for 9OP1/9OP2 and 1.42–1.69 t DM ha–1 yr–1 for 12OP. These values were lower than the DM production values obtained by cutting (6.5 t DM ha–1 yr–1 for 9OP1/9OP2 and 3.4 t DM ha–1 yr–1 for 12OP) or estimated based on light availability under oil palms (4.53 t DM ha–1 yr–1 for 9OP1/9OP2 and 2.95 t DM ha–1 yr–1 for 12OP), but all estimates indicated that a 9 yr old oil palm plantation can still supply >2 t DM ha–1 yr–1, which is higher than values reported in the literature. When dry matter of leaf harvested by cutting was compared with herbage dry matter consumed (estimated by MEB), the differences were smaller (1.3–1.7 t DM ha–1 yr–1 for 9OP1/9OP2 and 0.6–0.9 t DM ha–1 yr–1 for 12OP), indicating that the cattle may have grazed mostly leaves. Herbage ME (8.3–8.5 MJ ME kg DM–1) in the system was at the lower edge of the range for supporting high cattle liveweight gain, but herbage CP (10%–16%) was at the upper edge of the optimal range. The FCE values of the system were 32.2 kg DM kg LWG–1 for 12OP and 94–99 kg DM kg LWG–1 for 9OP1/9OP2, which are lower than that of the grazing cattle farming system in Sabah.

6.1 Introduction

Sabah has 1.511 million ha of agricultural land cultivated with oil palms, which is the largest area of any state in Malaysia (MPOB, 2014). The plantations are increasingly used for beef cattle farming for profit maximisation (Azid, 2008). Information on the actual area of oil palm plantation being used for cattle farming in Sabah is not available, but SKSB (2010) reported that it has used 22,949 ha of oil palm plantation to farm 8,018 cattle. Initially, cattle were introduced into oil palm plantations to control the undergrowth, but were later farmed systematically to produce beef commercially (Chen, 1990; Azizol and Norlizan, 2004; Azid, 2008).

The fundamental issue of feed planning in OPIC farming system is the lowering of herbage dry matter yield, ME and CP which occurs in response to shading as the oil palms in the plantation develop

from isolated individuals to canopy closure and as herbage matures during its regrowth cycle. In a 3–4

yr old un-weeded oil palm plantation, herbage dry matter yield is reported to be approximately 3.0 t

DM ha–1 yr–1 or sometimes 5.5–9.5 t DM ha–1 yr–1, but this decreases to 400–800 kg DM ha–1 yr–1 by

the time the plantation is 6–7 years old (Chen, 1990). The understorey herbage production is reported to

remain at 400–800 kg DM ha–1 yr–1 for the next 20 years (Jalaludin and Halim, 1998). There are also

reports of seasonal variation in dry matter yield. For example, in the northeast of West Malaysia,

herbage production in a 5 yr old oil palm plantation was reported to be 1991 kg DM ha–1 yr–1 in the 4-

month wet season from October–January and 1463 kg DM ha–1 yr–1 in 8-month dry season from

February–September (Hassan et al., 2004). In respect to the energy content, the total energy of herbage

per unit area per day is reported to decrease from 34 MJ ME ha–1 d–1 in a 3 yr old oil palm plantation to

10 MJ ME ha–1 d–1 in a 15 yr old oil palm plantation (Dahlan et al., 1993). The corresponding reported

decrease in CP is from 15% to 11%, when grasses replace the broad leaf plants in older plantations (>5 years old). These data indicate that low herbage DM production and nutritive value would limit the cattle carrying capacity of older plantations.

In Sabah, OPIC farming has been practiced for more than a decade. However, little information is published on the quantity of feed harvested and stocking rates in this category of beef production system. Most studies of this type published in Malaysia are based on data collected in West Malaysia. Hence, defining the feed demand and supply for OPIC farming system in Sabah would provide some quantitative basis for planning the future development of beef production under the local oil palm

plantation conditions. An alternative approach to gain an insight into the feed profile of OPIC farming system was the application of methodologies developed in New Zealand over recent decades, which was captured in the study described in Chapter 3, and adapted for use in Sabah in Chapter 4 for cut-and- carry feedlot cattle farming system and in Chapter 5 for grazing cattle farming system.

The present study was carried out in 2014. The oil palm company that agreed to participate in this study has been involved in OPIC farming since the 1990s and has a well-organized rotational stocking system in its oil palm plantations (Azid, 2008). In this study, a key part of the analysis was to capture the feed demand and supply of three separate beef cattle farms under OPIC farming system in Sabah: two 9 yr old plantations (9OP1 and 9OP2) and one 12 yr old plantation (12OP). As was the case in Chapter 4 and 5, the focus of the present chapter was to capture the feed demand and supply with a spreadsheet tool developed in the New Zealand phase of the study (Chapter 3) to first describe, and then to identify the opportunities to improve the OPIC farming system. As in the previous two chapters, the analysis is based on determination of feed demand using MEB, but also uses summary statistics like FCE. For further insight, measurements were also carried out on some nutritive value of herbage being grazed and some pre-grazing herbage mass (separated in time to estimate herbage accumulation). For data comparison with the results of the MEB and herbage cutting, the theoretical potential herbage productions of the system were also calculated based on the method described by Wilson and Ludlow (1990) and Cooper (1970).

6.2 Materials and methods