Beef Cattle Liveweight Gain Trial (2016)

Introduction

Fodder beet is now commonly grazed by beef cattle.  Several opinions and theories have been offered about which cultivars are best for this, with some suggesting that certain cultivars are better because they are more palatable, or softer, or have more water, or are higher out of the ground, or have more protein, or have greener leaf content.

This trial was designed to compare the performance of beef animals on different types of fodder beet in the same conditions, at the same time, and with the same type of animal. 

Methods

On a farm at Winchmore, mid-Canterbury, an area of land that was recently divided into three paddocks was chosen to establish the crops in October 2015. 

Three cultivars of beet were planted in each paddock, a medium dry matter fodder beet (cv. Kyros), and low dry matter fodder beet (cv. Feldherr), and a low dry matter mangel (cv. Brigadier).  Each crop received identical management inputs.  They established well and grew to typical yields (mean of 20.3 t DM/ha).

In May 2016, an even line of cattle of the same sex and breed were selected from a large line and randomly split into three mobs of 50 animals.  Once transitioned (14 days) onto fodder beet, they were weighed fresh off the crop for their starting weights (20 May).

The animals were all managed in the same way, aiming to maximise intake of fodder beet and cattle had access to straw at two kilograms per animal per day. 

The cattle were weighed again on 27 July, fresh off crop (see photo at top of page, cattle from the Kyros treatment).

Results

The cattle had an average daily weight gain of 1.0 kilogram per animal (Fig. 1), gaining 68 kilograms over 68 days.  There were no differences between the three types of beet. Crop utilisation was very high on each crop, with not enough residue left to be measured.

Figure 1.  Mean daily liveweight gain.

Conclusion

Growth rate of cattle and crop utilisation was not affected by the type of fodder beet grazed.  The sole determinant of relative profitability of fodder beet cultivars is therefore their yield potential.  Cultivars with higher yield will generate more profit.