Concerns for the welfare of finishing beef cattle, particularly in relation to housing conditions (space allocation and floor type), have been expressed at an EU and OIE (World Organisation for Animal Health level. There is the view that cattle housed on conventional slatted floors without access to lying areas should be provided with more space. The current space recommendation on concrete slats is 2.5m2 for an animal weighing 500kg.

In Ireland, approximately 73% of beef farms use concrete slatted floors. These have the advantage of low labour inputs for waste removal compared with solid floors or straw bedding.

Due to high capital costs of slatted housing, it is desirable to operate this housing system at high stocking densities and any alterations on space allocation requirement could have significant impact on livestock production in Ireland.

A study was conducted to evaluate the impact of housing characteristics, increased space allocation and floor type on the performance and welfare of beef heifers in a 100-day winter finishing period.

Scale

Due to the scale of the study and the number of animals required, it was conducted at the Kepak feedlot in Clonee, Co Meath, beginning in February 2015.

Two-hundred and forty late-maturing crossbred beef heifers were sourced and assigned to one of four treatments:

  • 3m2/head on slats.
  • 4.5m2/head on slats.
  • 6m2/head on slats.
  • 6m2/head on straw.
  • At the beginning, heifers weighed an average of 505kg and were aged between 18 and 22 months.

    The straw-bedded pens were located in the same shed as the concrete slats (Figure 1). A permeable plastic Geotextile sheet was placed over the slats to prevent the straw falling through. Straw was replenished every three days at a rate of 5kg/head/day.

    Every two weeks, the straw pens were cleaned out completely. Animals were housed in groups of 10, with six pens in each treatment. The costs of maintaining the six straw-bedded pens in the present study amounted to €105/week.

    During the study, heifers were fed a maize silage-based total mixed ration (TMR) ad lib.

    Feed offered was weighed daily and refusals were measured twice weekly in order to calculate feed intake.

    Heifers were weighed at the beginning, at the end and every three weeks during the study.

    Animal cleanliness was also recorded at these times and blood samples were taken to measure immunological and physiological variables that are indicative of welfare status.

    Prior to the beginning of the study, all hooves were examined for the presence of lesions. The hooves were examined again after slaughter. Animal behaviour was monitored at different stages during the study using CCTV cameras.

    Average slaughter weight for heifers housed on concrete slats was 635kg and kill-out percentage was 54%. Space allowance had no effect on the animal performance, with carcase weights of 343kg, 341kg and 344kg recorded for heifers housed at 3.0m2, 4.5m2 and 6.0m2 /head respectively.

    The average daily gain (ADG) of the heifers on the concrete slats was 1.26kg. Heifers on straw had a greater ADG (1.34kg) and slaughter weight (647kg).

    However, kill-out remained the same (54%) and the analysis showed no difference between the carcase weight of these heifers (347kg) and the heifers on concrete slats.

    Heifers housed on straw were significantly dirtier than those on concrete slats, which may explain the greater ADG and slaughter weight (Figure 2).

    There have been reports that under-stocked pens can cause cattle to become dirtier.

    However, the opposite was observed in the current study as cattle housed at 3.0m2/head were found to be slightly dirtier than those at 4.5 and 6.0m2/head.

    In summary

  • The space allowance and floor type had no effect on the blood parameters measured, with results indicating that none of the heifers in the study were under any stress.
  • The general condition of the heifers’ hooves was good. There was no effect of space allowance or floor type on the number of hoof lesions gained.
  • It is reported that healthy cattle lie for, on average, between 12.5 and 14.5 hours/day. The results of the present study reflect this; however, heifers on straw lay down for longer periods during the day – 13.9 hours versus 12.8 hours.
  • It is concluded that increasing the space allowance provided to animals on concrete slats above 3.0m2/head to 4.5m2 or 6.0m2 /head is not warranted based on the lack of any difference in carcase weight, stress indicators, hoof lesions or behaviour between the heifers housed at the three different stocking densities.

    With regard to floor type, housing heifers on straw had no effect on carcase weight, but increased dirt scores, and lying times compared to those on slats.

    As well as the added expense of purchasing straw, the associated labour costs must also be taken into consideration. The findings of this study will be used to inform policy at national and EU level on space allowance and floor type recommendations for finishing beef cattle.

    Michael Keane1, 2, Mark McGee1, Edward O’Riordan1, Alan Kelly2 and Bernadette Earley1.

    1 Animal & Grassland Research and Innovation Centre, Teagasc, Grange, Dunsany, Co Meath; 2 School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4.

    The authors gratefully acknowledge: the staff at Kepak for access to animals and the housing facility for the study; the assistance of the farm and technical staff at Teagasc, AGRIC, Grange, Co. Meath.