Strategies to reduce reliance on soya bean meal and palm kernel meal in livestock nutrition

J.M. Wilkinson,R.H. Young

doi:10.3920/jaan2020.0007

Abstract

Greenhouse gas emissions and loss of wildlife habitats have stimulated growing global concern over the continued expansion of soya bean and palm oilseed production on land recently converted from forest and natural grasslands. This paper reviews the roles of soya bean meal and palm kernel meal in livestock nutrition, drawing on research data to explore the potential for their replacement in nutritionally balanced diets. Soya bean meal is a widely used livestock feed due to relatively high levels of total protein and essential amino acids. Palm kernel meal has been used for many years in compound feeds for ruminant livestock and as a supplement to grazed pasture in periods of drought. A range of alternative sources of protein is available to replace soya bean and palm kernel meals, e.g. protected rapeseed meal can replace soya bean meal in diets for productive dairy cows, but constraints to widespread adoption include insufficient supply, anti-nutritional factors which require feeds to be processed or supplemented with enzymes, and imbalances in essential amino acids. Soya ‘milk’ made directly from soya beans is a less efficient process than producing milk from dairy cows, especially when they are grazed on pastures or given diets that do not contain soya bean meal.

Highlights

There is widespread concern about increasing global production of soya bean and palm oils, which doubled between 2000/01 and 2018/19 (Statista, 2019a) and is associated with deforestation, soil degradation, destruction of wildlife habitats, and the loss of natural grasslands in some regions of the world
It can be assumed that virtually all palm kernel meal is consumed as animal feed, with small quantities used as a raw material for other processes, such as protein extraction (Arifin et al, 2009)
Assuming an average 30% efficiency of N use (N in animal product as a percentage of N intake) by dairy cows, pigs and poultry (Wilkinson and Audsley, 2013), some 700,000 tonnes of N from the soya bean meal imported into the European Union (EU) in 2018/19 is likely to have been excreted via livestock manure to soil, water and air

Summary

Introduction

There is widespread concern about increasing global production of soya bean and palm oils, which doubled between 2000/01 and 2018/19 (Statista, 2019a) and is associated with deforestation, soil degradation, destruction of wildlife habitats, and the loss of natural grasslands in some regions of the world. Large quantities of oilseed meals are imported into the European Union (EU) for use as animal feed. Imports of soya bean meal into the EU in 2018/19 totalled 15.1 million tonnes, of which 9.1 million tonnes was from the USA and 4.8 million tonnes was from Brazil (European Commission, 2019). It can be assumed that virtually all palm kernel meal is consumed as animal feed, with small quantities used as a raw material for other processes, such as protein extraction (Arifin et al, 2009). This review covers the use of soya bean and palm kernel meals as livestock feeds. Alternative sources of dietary protein are discussed with the objective of reducing reliance on soya bean and palm kernel meals in livestock nutrition. The relative efficiencies of different livestock systems, in terms of converting human-edible and inedible feeds into human-edible animal products, have been discussed elsewhere (CAST, 1999; Wilkinson, 2011; Wilkinson and Lee, 2018) and are not considered in this paper

Composition of protein-rich animal feeds and human foods

Environmental issues

Soya bean meal

Palm kernel meal

Dairy cow milk versus soya drink

Findings

Conclusions