Performance and Carcass Characteristics of Australian Prime Lambs Grazing Lucerne and Cocksfoot Pastures Are Enhanced by Supplementation with Plant Oil Infused Pellets

Hung V Le,Peter D Nichols,Bunmi S Malau-Aduli,Aduli E O Malau-Aduli,Quang V Nguyen,Don V Nguyen

doi:10.3390/app11167275

Abstract

The aim of this study was to determine the effects of pasture (cocksfoot cv. porto (CFP) and lucerne) and supplementation of grazing lambs with pellets with or without plant oil infusion on performance and carcass characteristics. Forty-eight White Suffolk x Corriedale first-cross weaners were randomly assigned to one of four treatments in a split-plot experimental design: (1) CFP or lucerne pastures only (control); CFP or lucerne pastures supplemented with pellets infused with oil from (2) canola (CO); (3) rice bran (RBO) and (4) no oil pellets (NOP). Lucerne and CFP pastures were considered as the main plot effect, and played the role of basal pastures. Lambs grazing lucerne or CFP pastures with pellet supplementation achieved carcass weights of >22 kg at 9 weeks, which met the specific requirements of Asian and United States of America export markets. Pellet supplementation did not affect final liveweight, average daily gain, body length, withers height and chest girth of grazing lambs. Dressing percentage of lambs grazing CFP pasture with pellet supplementation and lambs grazing lucerne pasture with RBO supplementation increased compared with lambs on pasture grazing only. Although supplementing lambs on CFP pasture with CO had relatively negligible impact on feed conversion efficiency, it significantly increased over the hook trade value compared with lambs grazing CFP pasture only. In conclusion, lucerne or CFP pasture plus pellet supplementation produced lamb carcasses >22 kg suitable for the export market. CO had relatively low feed cost per unit daily gain (0.9 $AU/kg on CFP pasture and 0.6 $AU/kg on lucerne pasture) and could also be used as a tactical supplementation tool for increasing the carcass weight of lambs grazing CFP pasture.

Highlights

The lamb industry plays an important role in the Australian economy accounting for 7% ($4.2 billion) of the gross value of agricultural production and 6% ($2.8 billion) of the agricultural export income in 2018–19 [1]
Dry matter (DM) of pastures was 20.6%, which was considerably lower than supplemented pellets (~90%)
Some of the advantages from this study include the fact that carcasses of lambs grazing on lucerne pasture or CFP pasture with pellet supplementation were over 22 kg, implying suitability for meeting local and export market requirements

Summary

Introduction

The lamb industry plays an important role in the Australian economy accounting for 7% ($4.2 billion) of the gross value of agricultural production and 6% ($2.8 billion) of the agricultural export income in 2018–19 [1]. Export markets in Asia and the USA, which represent more than 50% of the total Australian lamb export volume [6], prefer carcasses of heavier weight specifications (22 kg or more) [7]. There is a need to evaluate the effect of legumes, improved pastures and specialized forages in lamb finishing systems on growth rate, carcass characteristics and fatty acid profiles of grazing lambs. The additional use of supplementation with diverse oils of plant origin and subsequent effects on growth rate and carcass traits needs to be evaluated in order to support lamb producers in the production of high quality and heavier carcasses for meeting the requirements of specific export markets [8]

Objectives

Methods

Results

Discussion

Conclusion