Pastures in Vanuatu

Livestock Production/Industries,

Growth of Bali Bulls Fattened with Forage Tree Legumes in Eastern Indonesia: Leucaena leucocephala in Sumbawa

The contribution of West Nusa Tenggara Province to domestic beef supply in Indonesia is relatively small, however, beef cattle are very important for the livelihoods of smallholder farmers in the region. Bali cattle (Boss javanicus) are the predominant breed as they are adapted to harsh nutritional conditions, are highly fertile and have low calf mortality (Toelihere 2003). While genetically capable of achieving a growth rate of 0.85 kg/d (Mastika 2003), Panjaitan (2012) identified poor nutrition as a severe limitation to animal growth in traditional village systems. Improving feed quality and supply is vital to increasing growth rates and product quality. Forage tree legumes such as leucaena (Leucaena leucocephala) offer the best chance of providing high quality feed to fatten Bali bulls in village systems where leucaena is well-adapted. Indeed, the feeding of leucaena has been practiced for about two decades in Sumbawa district of West Nusa Tenggara although the practice is limited to specific villages, mostly Balinese, even though farmers nearby have similar biophysical conditions and nutritional problems. The objective of this work was to characterize the best practices employed by farmers in Sumbawa that maximize growth rates by feeding leucaena so that their detailed knowledge can be passed onto other villagers in a pilot roll-out program (Kana Hau 2013)

Rates of Urinary Toxin Excretion in Unprotected Steers Fed \u3cem\u3eLeucaena leucocephala\u3c/em\u3e

Leucaena (Leucaena leucocephala) is a productive, nutritious, leguminous forage tree with high capacity for ruminant live weight gain. The plant does however contain the non-protein amino acid mimosine which is degraded within the rumen to 3-hydroxy-4(1H)-pyridone (3,4-DHP) with potential to cause adverse effects on animal health and production. Stock can be protected via rumen inoculation with the bacterium Synergistes jonesii, which is capable of degrading the toxin. However surveys have demonstrated sub-clinical toxicity is persisting in Queensland herds (Dalzell et al. 2012). Currently, testing for toxicity involves analysis of urine samples using high performance liquid chromatography (HPLC). A colorimetric urine test protocol has also been developed with the aim of providing a robust and reliable means for routinely testing herds (Graham et al. 2013). A significant problem affecting interpretation of the results from either method is the high variation in the concentrations of toxins excreted among animals on similar diets and by individual animals over time (Dalzell et al. 2012). Factors such as feed intake, water consumption, urine volume, as well as timing of sampling may be the cause of this variation. This research investigated the effect of sample timing by measuring the time taken for mimosine and its breakdown products, to present in the urine following the introduction of leucaena to the ration of cattle naïve to the plant

Growth of Bali Bulls on Rations Containing \u3cem\u3eSesbania grandiflora\u3c/em\u3e in Central Lombok, Indonesia

The demand for meat in Indonesia is currently growing by up to 8% per year, with beef cattle fattening identified as a major livestock industry (Purwantara et al. 2012). Bali cattle (Bos javanicus) account for almost 27% of total beef cattle in Indonesia; they are the predominant breed in the eastern islands and are highly favoured by smallholder farmers for their high fertility, low calf mortality and generally higher price at markets (Purwantara et al. 2012). Lombok in west Nusa Tenggara is one of the biggest suppliers of Bali cattle in Indonesia. A major constraint to improving the overall productivity of Bali cattle is their slow growth rate, due to lack of readily available, inexpensive, high-quality protein sources. Fodder tree legumes, such as sesbania (Sesbania grandiflora), offer a fast-growing, low-cost source of protein (Evans and Rotar 1987). Farmers in Lombok have established a unique and productive integrated farming system by planting sesbania trees along the bunds of rice paddies, providing forage and timber without significantly compromising rice yield (Dahlanuddin and Shelton 2005). As only the central part of Lombok is intensively planted with sesbania, a collaborative project funded by the Australian Centre for International Agricultural Research (ACIAR) is underway aiming to: (1) characterise the existing cattle fattening system; and (2) assess the impact of differing levels of sesbania feeding on the growth rate of Bali bulls from weaning to maturity (about 30 months old)

Detection of Toxicity in Ruminants Consuming Leucaena (\u3cem\u3eLeucaena leucocephala\u3c/em\u3e) Using a Urine Colorimetric Test

Leucaena (Leucaena leucocephala), a productive leguminous shrub for feeding ruminant livestock, contains the toxic amino acid, mimosine which post- ingestion is converted to 3,4-DHP and 2,3-DHP, isomers of dihydroxy-pyridone. While DHP generally does not exhibit acute toxic symptoms, it has been suggested that it is an appetite suppressant that reduces animal live weight gain (Jones 1994). With no observable symptoms, subclinical toxicity is difficult to detect (Phaikaew et al. 2012). In 1982 the DHP-degrading rumen bacterium named Synergistes jonesii was introduced into Australia as a potential solution to DHP toxicity as it spreads easily throughout cattle herds grazing leucaena (Jones 1994). However, toxicity events reported since the 2003 drought suggest that the toxicity status of herds, previously understood as being protected, may have changed. This may be the result of loss of effective S. jonesii bacteria from the rumen. Widespread subclinical leucaena toxicity has since been confirmed representing a significant economic threat to the beef industry (Dalzell et al. 2012). At present the testing for toxicity requires a sophisticated chemical analysis of urine samples using high performance liquid chromatography (HPLC). Producers, however, require a robust and reliable means to routinely test for toxicity in their herds. A colorimetric urine test protocol is available based on the colour reaction of mimosine and DHP with FeCl3 solution (Jones 1997). When this simpler colorimetric test has been used under a wide range of conditions false negatives have been reported. The aim of this study was to improve the reliability of the FeCL3 urine colour test

Diurnal Urinary Excretion of DHP in Steers Fed \u3cem\u3eLeucaena leucocephala\u3c/em\u3e

Leucaena (Leucaena leucocephala) contains the toxin mimosine which is quickly degraded by rumen microorganisms to isomers of dihydroxypyridine (DHP). DHP is detrimental to animal production, causing reduced thyroid hormones, reduced weight gain, goiter and severe deficiencies in essential minerals (Tsai and Ling 1971; Hammond 1995). There are several methods of testing for exposure to DHP toxicity but the simplest is the colorimetric urine spot test (Graham et al. 2013). Several researchers have noted high variability in the excretion of DHP among animals on similar leucaena diets (Dalzell et al. 2012; Phaikaew et al. 2012) and even in the same animal over sequential samplings (O\u27Reagain and Shelton 2013). They noted that it was possible to obtain samples with very low DHP in unprotected animals on high leucaena diets, leading to the false conclusion that the animal was successfully degrading DHP in the rumen. This study examined the extent and possible causes of variation of DHP concentration in spot urine samples taken over a 6-week period, including an intensive sampling over a 24 hour period

Leucaena Toxicity: A New Perspective on the Most Widely Used Forage Tree Legume

The tree legume Leucaena leucocephala (leucaena) is a high quality ruminant feed, vitally important for livestock production in the tropics despite the presence of mimosine in the leaves. This toxic non-protein amino acid has the potential to limit productivity and adversely affect the health of animals. The discovery and subsequent distribution in Australia of the ruminal bacterium Synergistes jonesii as an oral inoculum was shown in the 1980s to overcome these toxic effects. However, recent surveys of the status of toxicity worldwide; improved understanding of the chemistry and mode of action of the toxins; new techniques for molecular sequencing; and concerns about the efficacy of the in vitro inoculum; have cast doubt on some past understanding of leucaena toxicity and provides new insights into the geographical spread of S. jonesii. There is also confusion and ignorance regarding the occurrence and significance of toxicity in many countries worldwide. Ongoing research into the taxonomy and ecology of the Synergistes phylum, improved methods of inoculation, improved management solutions, along with awareness-raising extension activities, are vital for the future success of leucaena feeding systems

The Growth Response of Tropical and Sub-Tropical Forage Species to Increasing Salinity

There is currently a growing coal seam gas (CSG) industry in Queensland, Australia. The industry requires beneficial-use strategies to consume the significant volumes of water released during CSG extraction. Irrigation of tropical and sub-tropical forage species for beef production is one option, however coal seam (CS) water is of varying quality due to moderate to high salinity and alkalinity. The application of chemically amended CS water over time could potentially increase soil salinity, which is known to reduce plant biomass production. While there were studies of salinity tolerance of many tropical and sub-tropical forage species 30 years ago, there is a need to examine the tolerance of more recently released species and cultivars which are suitable for planting in the Queensland CSG area

The Efficacy of \u3cem\u3ein vitro Synergistes jonesii\u3c/em\u3e Inoculum in Preventing DHP Toxicity in Steers Fed Leucaena-Grass Diets

Leucaena leucocephala (leucaena) is a valuable forage tree legume for tropical animal production that contains the toxin mimosine. The breakdown products of mimosine in ruminants (3,4-DHP and 2,3-DHP) can adversely affect their health and limit weight gains (Jones and Hegarty 1984). The rumen bacterium Synergistes jonesii, introduced into Australia in 1983 was shown to completely and rapidly degrade these toxins to safe levels (Jones and Megarrity 1986). Since 1996, an in vitro produced inoculum has been made commercially available to Australian graziers (Klieve et al. 2002). Accordingly, the issue of leucaena toxicity in Australia was thought to be resolved. However, extensive testing in 2004 found that up to 50% of Queensland cattle herds consuming leucaena were excreting high levels of urinary DHP suggesting sub-clinical toxicity remained an issue for graziers (Dalzell et al. 2012). Some of these herds had previously been inoculated with in vitro S. jonesii suggesting the inoculum may not be able to either persist within a herd, or remain effective in degrading DHP. The aim of this study was to assess the capability of the in vitro S. jonesii inoculum to efficiently break down DHP in a controlled feeding trial environment

The Effect of Tree Densities on the Biomass of \u3cem\u3eLeucaena leucocephala\u3c/em\u3e and \u3cem\u3eChloris gayana\u3c/em\u3e Using a Nelder Fan Design

Leucaena leucocephala-grass pastures are widely used for ruminant feeding in tropical and subtropical regions. In Australia, over 200,000 ha of leucaena grass pasture have been planted with more plantings expected as it is recognized as the most productive, profitable and sustainable feeding system (Shelton and Dalzell, 2007). Planting densities and planting configurations for the leucaena component vary, ranging from single or double leucaena hedgerows 3 to 12 m apart (Radrizzani et al., 2010). There is little information about how tree/grass planting configurations and resulting inter- and intraspecific competition affect above and below-ground interactions. We hypothesise that individual leucaena tree biomass will be inversely related to leucaena tree density, with greatest competition at low density, while medium to high leucaena densities will reduce grass biomass production