title: Regrouping of pigs by body weight at weaning does not affect growth performance, carcass quality or uniformity at slaughter of heavy weight pigs.
abstract: We studied the influence of pen uniformity at weaning (7.5 ± 0.6 kg vs. 7.5 ± 1.2 kg body weight (BW ± SD)) and sex on growth performance during the nursery (7.5 to 27.3 kg BW) and the fattening (27.1 to 130.5 kg BW) phases and carcass quality of barrows and castrated females (CF). During the nursery phase, pigs from the more uniform pens had lower feed efficiency (P = 0.05) than pigs from the less uniform pens. Also, barrows had higher average daily feed intake (ADFI) (P < 0.05) and average daily gain (P < 0.001) and better feed efficiency (P < 0.001) than CF. During the fattening phase, initial pen uniformity did not affect growth performance of the pigs but barrows tended (P = 0.08) to have higher ADFI and worse feed efficiency than CF. Trimmed primal cut yield tended to be higher for the more uniform pigs and better for barrows than for CF (P = 0.09). It is concluded that regrouping of the pigs at weaning according to uniformity of BW did not affect growth performance or carcass quality of the pigs at slaughter. Castrated females might be used as an alternative to barrows for the production of carcasses destined to the dry-cured industry.
authors.affiliation: Departamento de Producción Animal, Universidad Politécnica de Madrid, Madrid, Spain.|CEI Campus Moncloa, UCM-UPM, Madrid, Spain.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Cámara
authors.affiliation: Departamento de Producción Animal, Universidad Politécnica de Madrid, Madrid, Spain.
authors.forename: Julio Díaz
authors.initials: JD
authors.lastname: Berrocoso
authors.affiliation: Copese S. A., Segovia, Spain.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Fuentetaja
authors.affiliation: CEI Campus Moncloa, UCM-UPM, Madrid, Spain.|Departamento de Producción Animal, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Clemente José
authors.initials: CJ
authors.lastname: López-Bote
authors.affiliation: Departamento de Producción Animal, Universidad Politécnica de Madrid, Madrid, Spain.|CEI Campus Moncloa, UCM-UPM, Madrid, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: De Blas
authors.affiliation: Departamento de Producción Animal, Universidad Politécnica de Madrid, Madrid, Spain.|CEI Campus Moncloa, UCM-UPM, Madrid, Spain.
authors.forename: Gonzalo G
authors.initials: GG
authors.lastname: Mateos
mesh_terms: D000003:Abattoirs; D000821:Animal Feed; D000822:Animal Husbandry; D000824:Animal Nutritional Physiological Phenomena / Q000502:physiology*; D000818:Animals; D001835:Body Weight; D002369:Castration; D004435:Eating / Q000502:physiology*; D005260:Female; D063427:Food Quality; D008297:Male; D008460:Meat; D013552:Swine / Q000254:growth & development* / Q000502:physiology*; D014886:Weaning
keywords: barrows; body weight uniformity; carcass quality; castrated females; growth performance