Animal Welfare Research Needs for Sheep

Following is a list of research priorities gaps identified during the sheep Code development process. Click here to visit the sheep Code web page for the Scientific Committee report and to view the full Code.

List compiled: February 2014

Environmental conditions

  • What are the welfare benefits and negative impacts (eg. concentrated camping increases coccidiosis risks) of the provision of shade?
  • Research on threshold values for air pollution that affect the welfare of housed sheep.

Facilities

  • The effect of flooring types on foot and leg health.
  • The relationships between bedding, flooring type and the risk of mastitis.
  • Further research on the components of handling systems that are stressful for sheep and measures that can be used to mitigate the stressful effects of handling. Examples of handling systems that should be evaluated include: lamb cradles used for tail- docking and castration; flip cradles for artificial insemination or foot trimming; and automatic squeezes.
  • More research is needed on slatted flooring (effect on feed intake, lying times, foot health and thermal comfort of nursing and weaned lambs, as well as adults).

Snow as a water source

  • Evaluation of the welfare implications of providing snow as the only source of water for sheep.

Health management

  • Identify the welfare implications of the lack of suitable products to deal with health issues and pain management in sheep.
  • More multi-disciplinary, large-scale, multi-year, multi-factorial, well-controlled research projects with frequent observations/sampling are required to examine the short- and long-term, behavioural, physiological, health, and welfare implications of various painful procedures. Evaluation of effectiveness of anesthetic and analgesic drugs and their method of administration to reduce pain responses to procedures. This should include studies on the efficacy and safety of NSAIDS (e.g. due to their anti-prostaglandin nature, there may also be drawbacks to their use in very young animals). In addition, an evaluation of the use of injectable local anesthetic agents should examine the prevalence of adverse outcomes following their use in the ‘field’. 
  • Epidemiological studies of the role of tail docking and the length of tail docked in controlling flystrike. Although flystrike occurs in pastured lambs and sheep in Canada, no research has been published on the risks and mitigating effects of tail docking in relation to the risk of flystrike. Epidemiological studies of the health implications e.g. risk of fly strike or rectal prolapse, of the length of tail docked. Evaluation of the practicality of using a hot iron for tail docking under differing management systems.
  • Effectiveness of management procedures to reduce risk of mortality due to hypothermia and long-term follow-up on health.

Castration

  • Evaluation of welfare implications of using callicrate band castration in lambs at different ages. Evaluation of implications of not castrating lambs on sheep management and carcass, and meat quality.

Reproduction

  • Comprehensive evaluation of the welfare implications of accelerated lambing in Canada relative to traditional systems. Outcomes relevant to welfare should include the: effect on lamb mortality by season and inter-lambing interval, longevity of the ewe and disease rates associated with lambing and lactation events, and effects on lamb diseases. The comparison group should be matched by age of ewe and season of birth in annual lambing systems.
  • Implications of dystocia on pain and maternal care.
  • Implications of supervision of lambing on the risk of dystocia. For example, effect of frequency of observation, group size, criteria for intervening on lamb survival and ewe comfort. More research on criteria for when to intervene should also be studied (e.g. how long after the fetal membranes have broken should one intervene).
  • Effectiveness of management procedures to reduce risk of ill-health due to inadequate absorption of colostral immunoglobulins, including the effectiveness of colostrum replacement products for short-term and long-term health of the lamb.
  • Management systems to reduce mismothering. More research is needed on methods to improve ewe-lamb bonding and lamb survival.
  • The welfare implications of artificial rearing versus normal suckling on behaviours in the group.
  • The welfare implications of methods used for cross fostering. For example, more research on lamb survival and growth of lambs that have been cross-fostered under different systems.

Weaning

  • The welfare implications of the age of lamb at weaning and the implications on both lamb and ewe performance. There is little to no research on the welfare implications of forced weaning, i.e. removal of ewes from lambs (or vice versa). Although natural weaning has drawbacks for disease control and rebreeding, the development of methods of more natural weaning should be studied in sheep. The welfare implications of the methods used for weaning after artificial rearing.

Euthanasia

  • Comprehensive evaluation of the welfare implications of different methods of euthanasia of sheep.
  • The effectiveness of blunt trauma to cause in a consistent manner, immediate loss of consciousness and death in lambs of various ages and weights).
  • The effectiveness of captive bolt apparatus with an extended bolt and a large charge to kill sheep.
  • The effectiveness of different methods of shooting i.e. type and calibre of weapon and projectile, and position on head of entry wound to kill sheep.