Animal welfare aspects in respect of the slaughter or killing of pregnant livestock animals (cattle, pigs, sheep, goats, horses)

Abstract

This scientific opinion addresses animal welfare aspects of slaughtering of livestock pregnant animals. Term of Reference (ToR) 1 requested assessment of the prevalence of animals slaughtered in a critical developmental stage of gestation when the livestock fetuses might experience negative affect. Limited data on European prevalence and related uncertainties necessitated a structured expert knowledge elicitation (EKE) exercise. Estimated median percentages of animals slaughtered in the last third of gestation are 3%, 1.5%, 0.5%, 0.8% and 0.2% (dairy cows, beef cattle, pigs, sheep and goats, respectively). Pregnant animals may be sent for slaughter for health, welfare, management and economic reasons (ToR2); there are also reasons for farmers not knowing that animals sent for slaughter are pregnant. Measures to reduce the incidence are listed. ToR3 asked whether livestock fetuses can experience pain and other negative affect. The available literature was reviewed and, at a second multidisciplinary EKE meeting, judgements and uncertainty were elicited. It is concluded that livestock fetuses in the last third of gestation have the anatomical and neurophysiological structures required to experience negative affect (with 90-100% likelihood). However, there are two different possibilities whether they perceive negative affect. It is more probable that the neurophysiological situation does not allow for conscious perception (with 66-99% likelihood) because of brain inhibitory mechanisms. There is also a less probable situation that livestock fetuses can experience negative affect (with 1-33% likelihood) arising from differences in the interpretation of the fetal electroencephalogram, observed responses to external stimuli and the possibility of fetal learning. Regarding methods to stun and kill livestock fetuses at slaughter (ToR4), sets of scenarios and respective actions take account of both the probable and less probable situation regarding fetal ability for conscious perception. Finally, information was collated on methods to establish the dam's gestational stage based on physical features of livestock fetuses (ToR5).

Fetal age assessment for Holstein cattle

“…one around last third of gestation and one for the last 10 th of gestation. These two examples were selected to demonstrate any gain in a multivariable model over a univariable model for two time-periods identified of potential (if pregnancy is in last third of gestation or not [9] or if pregnancy is in last 10 th of gestation or not [1]). The models were thus constructed with: GAS as the outcome and all quantitative variables as potential predictors.…”

Guidance on Communication of Uncertainty in Scientific Assessments

“…Animal welfare aspects in respect of the slaughter or killing of pregnant livestock animals (prevalence) (EFSA AHAW Panel, )…”

“…Example of a PDF graph, based in the 'Prevalence of pregnant slaughtered animals in the EU' example(EFSA AHAW Panel, 2017) …”

Slaughter of Pregnant Cattle in Denmark: Prevalence, Gestational Age, and Reasons

“…Concerns have been raised regarding the ability of foetuses to experience pain or other negative affect based on hormone values, behaviour, heart rate, and electroencephalograms, in the last trimester of gestation [1,2,9]. However, the general consensus is that these concerns are unfounded [10], since the above-mentioned factors are not seen as indicators of pain, because pain requires actual and not just potential sentience, and according to the state-of-the-art literature, this does not apply to a bovine foetus in an unopened uterus at an abattoir [11,12,13,14,15,16] (see however, Campbell et al, 2014 [17] for a discussion of uncertainties relating to the conclusions of this literature). Nevertheless, in 2017, Germany banned the slaughter of pregnant cattle during the last trimester of gestation to protect the foetus [18].…”

“…However, no recent data are reported, and the two studies mentioned above focused only on dairy cattle rather than cattle kept in an extensive production system, which has a different production cycle. A recent systematic literature review followed by expert knowledge elicitation [21] characterised the main reasons for slaughter of pregnant cattle as economic (e.g., low productivity), management-related (e.g., false-negative pregnancy diagnoses or pregnant cows being calmer than non-pregnant cows and thus resulting in fewer injuries in the herd), and health and welfare related (e.g., lameness, mastitis, disease control) [10].…”