Effect of space allowance and floor type on performance

Irish suckler and beef farms differ from their European counterparts, with slatted housing being the dominant type of winter housing and finishing accommodation compared to straw bedding in many other EU countries and the UK.

With Ireland’s beef industry reliant on exports, it is important that the industry can showcase best practice at all stages of the supply chain.

During the recent Teagasc beef conference, Dr Bernie Earley of Teagasc Grange said the issue of floor type and space allocation has been raised on numerous occasions in recent years by EU and UK retailers and international welfare advisory bodies. She said there have been suggestions for the phasing out of concrete slatted floors and replacing them with solid lying areas, or slats with rubber mats. As such, it is important that robust scientific evidence is available to accurately inform the debate.

Bernie said there is no EU regulation yet concerning floor type or space allocation, but this is likely to come down the line and could mean changes, in particular for beef farms.

Extensive research

Bernie has, and continues to, lead research in this area and delivered an extensive overview in one of the online conference sessions. The results of one study presented included 240 late-maturing crossbred beef heifers split into four treatments.

The first three treatments were animals housed on concrete slatted floors (CSF) with a space allowance of 3m2 (slightly above the current recommendations), an intermediate space allocation of 4.5m2 and a generous allocation of 6m2, which Bernie says is in line with what is being proposed. There was also a straw bedding treatment at this 6m2 space allowance.

In total, there were six pens per treatment and 24 pens altogether, with the study carried out in the Kepak Clonee finishing unit.

Animals were weighed, dirt-scored and blood-sampled every 21 days. All four hooves of each animal were also examined at the start and end of the study to check for the presence of lesions or any abnormalities, while animal behaviour was recorded using CCTV. Animals were slaughtered after a 105-day finishing period, at which stage carcase traits were also collected.

Even though animals in the 6m2 treatment had excess space, they tended to congregate together when lying, a trend which Bernie says is commonly seen in such experiments.

Bernie said that adhering to a recommendation of 5kg straw per animal per day would be impossible in an Irish context

There was also more accumulation of faecal matter on the slats, as animals were not treading through it as often as they would in pens with a lower space allowance.

Straw bedding was provided by applying it on top of a geotextile membrane placed on concrete slats. It was topped up at a rate of 150kg per pen every three days.

Bernie said that adhering to a recommendation of 5kg straw per animal per day would be impossible in an Irish context, as there would just not be enough straw available. The straw was allowed to build up to a level of 25in and was removed every two weeks.

Results review

There was no significant difference in performance across the three concrete slatted floor treatments. The dry matter intake was exactly the same at 11.1kg daily, as detailed in Table 1. The animals with a space allowance of 4.5m2 did record a higher average daily gain (ADG of 1.28kg per day v 1.18kg and 1.19kg) and better feed conversion efficiency, but with a slightly lower kill-out, there was no difference in carcase weight across the groups.

Looking at the performance of the two treatments with a 6m2 space allowance, the straw-bedded group achieved a significantly higher ADG of 1.34kg versus 1.19kg for the concrete slats, as detailed in Table 2, but Bernie said there was only a small numerical difference in carcase weight (347kg v 341kg), which was not significantly different.

With regard to welfare measurements, there was no difference in hide dirt scores across the three CSF treatments, but the animals on the straw-bedded treatment had a dirtier hide despite the high volume of straw and bedding management. Animals lay down for one hour longer in the straw-bedded pens.

International comparisons

The conclusion of the study showed no significant benefit in performance or animal welfare metrics in exceeding the recommended space allowance for CSF.

This was also the outcome from a review of published international studies on the same topic, with this analysis also showing that performance will be significantly compromised where the space allowance is below the current recommendation and set at less than 2m2 per animal.

This should be borne in mind as the winter progresses and animals are growing, which could potentially depress performance if recommended stocking rates for different categories of animals are not adhered to.

Bernie also presented a review of published international scientific literature examining the effect of underfoot conditions on animal performance and welfare. The details of the findings are summarised in Table 3, with the data suggesting no significant difference between CSF and straw bedding.

Next week, we will detail the performance of animals on concrete slatted floors versus rubber mats and focus on the latest information from a recent study carried out in Teagasc Grange.