Winter Beef series: Avoiding ‘the weanling weight struggle’

Winter Beef series is in conjunction with Teagasc’s DairyBeef 500 Campaign

With many grazing weanlings already housed and the end line now in sight for those still out, it is important that dairy calf-to-beef producers have a feeding plan in place for the coming months.

At this stage, the quantity and the quality of the silage that you have in your yard can’t be changed.

However, a plan needs to be drawn up to take into account the amount of forage available on the farm, forage quality and required performance of animals.

Too often, the winter period is a time when many calf-to-beef producers struggle to hit the average daily gain (ADG) targets that are required.

The management of these weanlings over the winter is a very important factor in achieving a margin from this enterprise.

Poor management may lead to either longer finishing periods or the production of lighter carcasses, both of which will have negative impacts on the potential profitability of the system.

Ready to thrive

The primary aim of the winter-housing period on calf-to-beef farms is to ensure weanlings are in good condition and ready to thrive at grass next spring.

The ideal target weight gain for weanlings over the winter is 0.6kg/head/day. Over a 120-day winter, this amounts to 72kg of weight gain.

There is no evidence that having a higher ADG over the first winter will lead to earlier finishing or heavier carcass weights as compensatory growth will occur when cattle get to grass in the spring.

However, if silage quality is poor and meal supplementation is not adjusted accordingly, animals coming out of the sheds next spring will be too far behind the target weight to avail of compensatory growth and consequently, will not reach target weights later on in life.

Dry matter digestibility (DMD) is the primary factor influencing the nutritive value of grass silage and subsequently, the performance of cattle.

Target animal growth rates during the first winter can be achieved on grass silage supplemented with concentrates as outlined in Table 1.

Low-DMD silage means higher levels of concentrate supplementation have to be used to achieve the same growth rates. This highlights the importance of having good-quality silage for growing cattle.

Without carrying out a silage analysis, you are likely to be losing money through either overfeeding unnecessary expensive concentrates (70+ DMD silage scenario) or missing out on weight gain targets (60 DMD silage scenario)

Table 1: ADG from different silage qualities and meal:

Typically, weanlings require 13–14% crude protein in their diet. If your grass silage analysis comes back at less than 12% protein, it then needs to be balanced with concentrates with a 15 -16% crude protein content.

However, if the silage analysis is greater than 12% for crude protein, then a 14% ration is adequate.

What is often forgotten is that energy is the most important measure required by growing cattle.

Concentrates fed should be medium to high in energy (0.90-0.96UFL). Concentrates that have high levels of cereals, pulps and soya are ideal for weanlings.

Shed considerations

Careful attention should be paid to the size of the shed available, as overcrowding can lead to a significant reduction in animal performance.

Many farmers undervalue the critical role that good ventilation in their cattle housing plays in achieving good animal performance. A good movement of air throughout the shed will help keep cattle healthy, which allows them to thrive.

Farmers should not overstock sheds and should ensure ventilation is sufficient. The two space requirements that need consideration are floor space and feeding space (Table 2).

Table 2: Floor space and feeding space requirements