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In total, 240 pigs were used to compare growth performance and carcass quality traits of immunocastrated males (ICM), surgically castrated males (SCM), and intact females (IF) of crossbreds from Large White × Landrace females and Duroc (DU) or Pietrain (PI) sires destined to the dry-cured industry. Between the 2 Improvac injections (87 and 137 d of age), ICM and IF had less ADG than SCM (P < 0.01). Also, ICM ate less feed than IF and both less than SCM (2.33, 2.55, and 2.77 kg/d; respectively; P < 0.001) and consequently, ICM had better G:F than SCM and IF (P < 0.001). From second Improvac injection to slaughter (137 to 164 d of age), ICM were more efficient than IF and both more efficient than SCM (0.346, 0.323, and 0.300 g/g; respectively; P < 0.001). The differences in growth performance among genders observed in this period were more pronounced for the PI than for the DU crossbreds (P < 0.05 for the interaction). For the entire experimental period (87 to 164 d of age), gender did not affect ADG for DU crossbreds but for PI crossbreds ICM and SCM had greater ADG than IF (P < 0.05 for the interaction). The ICM pigs had better feed efficiency (0.406, 0.364, and 0.380; g/g; P < 0.001) and lower carcass yield (76.6, 78.1, and 78.8%; P < 0.001) than SCM or IF. Carcasses from IF were leaner than carcasses from SCM with carcasses from ICM being intermediate (P < 0.01). Ham and loin (P < 0.001) yields were greater for IF than for ICM or SCM. Intramuscular fat content was lower for IF than for SCM with that of ICM being intermediate (3.5 vs. 3.9 and 3.7%; P < 0.05). Cumulatively, crossbreds from DU sires had greater ADG (1.167 vs. 0.986 kg/d; P < 0.001) and ADFI (3.07 vs. 2.56 kg/d; P < 0.001) and more intramuscular fat (P < 0.001) but less ham and loin yields (P < 0.01) than crossbreds from PI sires. It is concluded that growth performance was better but carcass yield less for ICM than for SCM and IF. Intramuscular fat content in LM was less for IF than for SCM with ICM intermediate. Crossbreds from Duroc sires grew faster and had more intramuscular fat but less ham yield than crossbreds from Pietrain sires. Therefore, ICM should be preferred to SCM and Duroc crossbreds should be preferred to Pietrain crossbreds to produce carcasses destined to the production of primal cuts for the dry-cured industry.

In total, 360 pigs slaughtered at 125 kg of BW and destined for the dry-cured industry were used to study the influence of sex and castration [immunocastrated males (IMC), surgically castrated males (CM), and intact females (IF)] in 2 terminal Large White sire lines [Top York (TY) and Tempo (TE)] on growth performance and carcass and meat quality. The female line was Large White × Landrace. The IMC pigs were immunized against gonadotropin-releasing factor (GnRF) with Improvac at 78 (experimental d 16) and 126 (experimental d 64, 48 d before slaughter) d of age. Each of the 6 treatments was replicated 6 times (10 pigs/pen). Through the day of the first Improvac injection (62 to 78 d of age), IMC and IF grew at a slower rate (P < 0.001) than CM with no differences (P = 0.95) in feed intake. The CM had greater G:F than IF, with IMC being intermediate (P < 0.01). From 78 to 126 d of age (between Improvac injections), the IMC pigs ate less feed (P < 0.001) and grew at a slower rate than CM, with IF being intermediate. The IMC pigs were more feed efficient than IF, and both were more efficient than CM (P < 0.001). However, from 126 to 174 d of age (from the second Improvac injection to slaughter), IMC pigs grew at a faster rate (P < 0.001) and were more efficient (P < 0.001) than IF and CM. Overall, IMC and CM pigs grew at a faster rate (P < 0.01) than IF, and IMC were more efficient than the other sexes (P < 0.001), but had reduced (P < 0.001) carcass yield compared with CM and IF. The IMC and IF pigs also had less (P < 0.001) backfat depth than CM. Intact females had greater (P < 0.01) loin yield but less intramuscular fat than IMC and CM and greater (P < 0.05) fresh and trimmed ham yields than CM, with IMC being intermediate. Crossbreds from TE sires grew at a faster rate (P < 0.001) than crossbreds from TY sires, but no differences (P = 0.23 and 0.14, respectively) were found for feed intake or efficiency. Crossbreds from TY produced greater (P < 0.05) fresh and trimmed ham yield, but less (P < 0.01) loin yield and intramuscular fat content than crossbreds from TE. In conclusion, IMC pigs are more efficient, but have less carcass yield than CM and IF. The intramuscular fat content is least for IF and similar for IMC and CM. Crossbreds from TE sires were larger and had greater intramuscular fat content, but slightly less trimmed ham yield compared with crossbreds from TY sires. Immunocastrated pigs can replace CM for the production of heavy pigs destined for the dry-cured industry. Because of increased carcass weight, crossbreds from TE sires may have an advantage over crossbreds from TY sires.