Effects of tail docking and teeth clipping on the physiological responses, wounds, behavior, growth, and backfat depth of pigs

: The objective of this experiment was to compare the effects of tail docking and teeth clipping on the growth and behavior of pigs. Pigs (n = 126) from 21 litters (6 pigs/litter) were blocked by birth weight, and assigned at 3 d of age within blocks to either teeth clipping and tail docking (processed) or control (sham-processed). Vocalizations of pigs were recorded during the procedures, and behavior was observed during the lactation, nursery, and growing periods. Blood samples were collected on d 21 to measure serum IgG concentrations. Wounds on the body and tail were assessed by inspecting both sides of the body and tail at 70, 110, and 160 d of age, whereas BW were recorded at 10, 21, 70, and 160 d of age. Fat and LM depths were measured ultrasonically on growing pigs at 160 d of age. Clipped and docked pigs vocalized more (1.06 vs. 0.62 s; P < 0.01) during processing, and processed pigs were observed lying alone more often (P = 0.03) during the 3 d after processing and the entire suckling period; however, teeth clipping and docking did not (P ≥ 0.14) alter the frequency that pigs spent suckling, standing, huddling, playing/fighting, or sitting during the first 3 d or between 5 and 15 d after processing. Social behavior during the nursery (P ≥ 0.23) and grower phases (P ≥ 0.18) was unaffected by clipping and docking, but processed pigs rested more (P = 0.03) during the nursery period and were less (P ≤ 0.01) interested in exploratory behaviors during both phases, especially during pen (P ≤ 0.04) and enrichment investigations (P ≤ 0.02). Teeth clipping and tail docking reduced ADG between 10 and 21 d (P = 0.01) and 21 to 70 d of age (P = 0.04), resulting in lighter BW at 21 (P = 0.01) and 70 d of age (P = 0.08) compared with sham-processed pigs. However, 160-d BW (P = 0.62), d 70 to 160 ADG (P = 0.23), and G:F (P ≥ 0.15) were not affected by teeth clipping and tail docking. Additionally, there was no difference between sham and processed pigs for fat depth (P ≥ 0.05), LM depth (P = 0.93), or estimated percent muscle (P = 0.27). Even though tail docking and teeth clipping appear to produce short-term pain and distress, results of this experiment indicate that leaving the teeth and tails intact have no detrimental effects on mortality, morbidity, live performance, or carcass merit of growing-finishing pigs.