|Carroll, Jeffery - Jeff Carroll|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 3/18/2002
Publication Date: N/A
Technical Abstract: A trial was conducted to determine pre- and postweaning performance of pigs injected with dexamethasone (Dex) at 1 or 24 h after birth. In Exp1, 225 pigs were assigned according to birth weight and sex to three treatments. Treatments (Trt) included saline (Cont), Dex1 (2 mg/kg BW i.m. injection of Dex within 1 h of birth) and Dex24 (2 mg/kg BW i.m. injection of Dex within n24 h after birth). Birth weights (1.56+/0.36 kg) did not differ among Trt (P>0.96) or between sexes (P>0.70). For body weight (BW) at weaning (15 d), there was a Trt x Sex interaction (P<0.02) with Dex males 12% heavier than Cont males (4.8 vs 4.3 kg, respectively) and Dex females lighter than Cont females (4.5 vs 4.8 kg, respectively). In Exp2, 186 pigs from Exp1 were transported to a nursery facility. There were 10 pens/Trt/Sex (60 pens). At the end of Exp2 (49-d period) there was a Trt x Sex interaction (P<0.01) for BW with Dex barrows 8% heavier than the Cont barrows (30.0 vs 27.8 kg, respectively) and no difference in gilts. No differences in feed efficiency (G:F) were observed during the nursery period. In Exp3, pigs from the nursery were moved to a finishing facility where there were 4 pens/Trt/Sex (24 pens). Real-time ultrasound was used to measure 10th rib backfat depth (BF) and loin-eye area (LEA). At the end of Exp3 (83-d period) there was a Trt x Sex interaction (P<0.04) for final BW with Dex barrows being 4.9 kg heavier than Cont barrows (119.6 vs 114.7 kg, respectively) and no difference in gilts. No treatment differences were observed for BF, LEA or G:F (P>0.10). These studies demonstrate that Dex given within 24 h of birth significantly improves both pre- and postweaning performance of barrows with no beneficial effects on gilts.