Comparison of frontal-sinus and poll shot locations as secondary methods for euthanizing dairy cattle with a penetrating captive bolt gun

Abstract

Humane euthanasia is a crucial component of dairy farm animal welfare programs. When using either a gunshot or captive bolt, the frontal-sinus area is well established as the primary shot location, but a secondary shot is often used as well. The objective of this study was to evaluate the efficacy of 2 different secondary shot locations. Cattle from a commercial dairy operation (n = 44) were randomly assigned to receive a secondary shot in the frontal-sinus or poll location and clinical signs of consciousness were assessed. A subsample of adult cattle heads (n = 6) were also evaluated to assess the extent of trauma. With the exception of heartbeat, all signs of sensibility were absent immediately following the first frontal-sinus shot and remained absent until confirmation of death, regardless of treatment (P > 0.05). Relatively fewer animals shot in the poll location had a heartbeat 5 min after being shot (P = 0.03). Pathology results on the subsample of adult cattle showed poll shots rarely penetrated beyond the cerebrum and only 1 of 6 animals had a severed brainstem. We conclude the frontal-sinus and poll locations are similarly effective secondary shot locations, and brainstem damage may not be necessary for irreversible insensibility and death.

Assessment of time to death, brain tissue damage and clinical signs of consciousness in mature Jersey x Holstein cattle receiving a secondary penetrating captive bolt gunshot at the poll or frontal sinus locations

“…Unfortunately, little is known about the relative efficacy of these different secondary shot locations on time to death and clinical signs of consciousness. Previous research comparing different secondary PCBG shot locations failed to detect differences in the persistence of clinical signs of consciousness or time of death; 12 however, this research involved mostly young dairy animals (mean age = 242 d ± 177 (range 14 to 625) and it is not clear whether similar results would be obtained in mature animals with different cranial characteristics. To address this uncertainty, we set out to examine the relative efficacy of 2 secondary shot locations (frontal vs poll) on time to death and clinical signs of consciousness in a sample of mature Jersey x Holstein cross cattle.…”

“…Clinical signs of consciousness were selected on the basis of previous research and are detailed in Table 1. 12 Unconsciousness was defined as the absence of all clinical signs assessed. 13 Death was defined as the absence of all clinical signs assessed and a lack of an auscultable heartbeat.…”

Assessment of United States Department of Agriculture Food Safety Inspection Service Humane Handling Enforcement Actions: 2018–2020

“…Multiple factors may have contributed to the number of ineffective stunning attempts, including placement, equipment performance, and operator training. There is a growing body of literature related to placement of mechanical stunning across species (Bovine: Dewell et al (2016) ; Gilliam et al (2012 , 2016 , 2018 ); Robbins et al (2021) ; Schiffer et al (2014) ; Caprine: Plummer et al (2018) ; Porcine: Anderson et al (2019 , 2021 , 2022 ); Kramer et al (2021) ). To ensure effective stunning and safeguard animal welfare, it is important that alternative placements which have not been validated are not used for mechanical stunning.…”

Quantification of cooling effects on basic tissue measurements and exposed cross-sectional brain area of cadaver heads from Holstein cows > 30 mo of age

“…PCB is also a method of stunning and euthanasia for other livestock species, including swine ( AVMA, 2016 , 2020 ; HSA, 2016 ; National Pork Board and American Association [ NPB and AASV], 2016 ; CFIA, 2019 ), sheep ( AVMA, 2016 , 2020 ; HSA, 2016 ; CFIA, 2019 ), and goats ( AVMA, 2016 , 2020 ; HSA, 2016 ; CFIA, 2019 ). Recently, there has been an interest in better understanding various aspects of PCB use for cattle ( Gilliam et al., 2012 , 2016 , 2018 ; Kline et al., 2019 ; Wagner et al., 2019 ; Casagrande et al., 2020 ; Robbins et al., 2021 , 2023 ) and swine ( Anderson et al., 2019 , 2021a ; Kramer et al., 2021 ). For cattle, varying bolt lengths ( Kline et al., 2019 ; Wagner et al., 2019 ), physical landmarks for the frontal PCB placement ( Gilliam et al., 2012 , 2016 , 2018 ), security stuns ( Casagrande et al., 2020 ), and a second shot in the poll placement ( Robbins et al., 2021 , 2023 ) have been evaluated.…”

“…Recently, there has been an interest in better understanding various aspects of PCB use for cattle ( Gilliam et al., 2012 , 2016 , 2018 ; Kline et al., 2019 ; Wagner et al., 2019 ; Casagrande et al., 2020 ; Robbins et al., 2021 , 2023 ) and swine ( Anderson et al., 2019 , 2021a ; Kramer et al., 2021 ). For cattle, varying bolt lengths ( Kline et al., 2019 ; Wagner et al., 2019 ), physical landmarks for the frontal PCB placement ( Gilliam et al., 2012 , 2016 , 2018 ), security stuns ( Casagrande et al., 2020 ), and a second shot in the poll placement ( Robbins et al., 2021 , 2023 ) have been evaluated. For swine, alternative PCB placements have been evaluated for market hogs ( Anderson et al., 2019 ) and sows and boars ( Anderson et al., 2021a ; Kramer et al., 2021 ).…”