A meta-analysis of cortisol concentration, vocalization, and average daily gain associated with castration in beef cattle. (October 2017)

• Record Type: Journal Article
• Authors: Canozzi, Maria Eugênia Andrighetto; Mederos, America; Manteca, Xavier; Turner, Simon; McManus, Concepta; Zago, Daniele; Barcellos, Júlio Otávio Jardim
• Is Part Of: Research in veterinary science. Volume 114(2017)
• Page Start: 430
• Page End: 443
• Publication Date: 2017-10
• Subjects: Analgesia -- Animal welfare -- Pain; Veterinary medicine -- Periodicals; Veterinary Medicine -- Periodicals; Médecine vétérinaire -- Périodiques; Médecine vétérinaire -- Recherche -- Périodiques; Diergeneeskunde; 636.089
• DOI: 10.1016/j.rvsc.2017.07.014
• Languages: English
• ISSNs: 0034-5288

Abstract

Abstract: A systematic review and meta-analysis (MA) were performed to summarize all scientific evidence for the effects of castration in male beef cattle on welfare indicators based on cortisol concentration, average daily gain (ADG), and vocalization. We searched five electronic databases, conference proceedings, and experts were contacted electronically. The main inclusion criteria involved completed studies using beef cattle up to one year of age undergoing surgical and non-surgical castration that presented cortisol concentration, ADG, or vocalization as an outcome. A random effect MA was conducted for each indicator separately with the mean of the control and treated groups. A total of 20 publications reporting 26 studies and 162 trials were included in the MA involving 1814 cattle. Between study heterogeneity was observed when analysing cortisol ( I 2 = 56.7%) and ADG ( I 2 = 79.6%). Surgical and non-surgical castration without drug administration compared to uncastrated animals showed no change ( P ≥ 0.05) in cortisol level. Multimodal therapy for pain did not decrease ( P ≥ 0.05) cortisol concentration after 30 min when non-surgical castration was performed. Comparison between surgical castration, with and without anaesthesia, showed a tendency ( P = 0.077) to decrease cortisol levels after 120 min of intervention. Non-surgical and surgical castration, performed with no pain mitigation, increased and tended to increase the ADG by 0.814 g/d ( P = 0.001) and by 0.140 g/d ( P = 0.091), respectively, when compared to a non-castrated group. Our MA study demonstrates an inconclusive result to draw recommendations on preferred castration practices to minimize pain in beef cattle. Highlights: Castration is a husbandry practice raising welfare concerns in farm animals. Meta-analysis was performed on cortisol and ADG following castration in beef cattle. Cortisol did not differ between uncastrated, surgical and non-surgical castration. Multimodal pain relief did not mitigate cortisol increase in castrated cattle. Cortisol and ADG might not be reliable indicators of castration pain in beef cattle.