EFECTOS DE IMPLANTES, OLAQUINDOX Y SEXO SOBRE LAS CARACTERÍSTICAS DE LA CANAL DE CERDOS
Effects of implants, Olaquindox and sex on carcass characteristics of swine
Nelson Huerta Leidenz
Enio Wilhelm
Guillermo Ríos Fuenmayor
Ángel Páez
Edmundo Rincón
Nancy Jerez Timaure
Facultad de Agronomía,
Universidad del Zulia,
Maracaibo, Estado Zulia, Venezuela
RESUMEN
Se utilizaron 54 cerdos Landrace y Yorkshire en un diseño completamente aleatorizado. El análisis de varianza covarianza por cuadrados mínimos para cada raza, incluyó los efectos del sexo (hembras y machos castrados), tratamiento (DES ~ implante de 15 mg de Dietilestilbestrol; ZL = implante de 12 mg de Zeranol; OX = adición de Olaquindox en la ración y T = testigo) y la interacción tratamiento x sexo, teniendo como covariable el peso inicial. En cerdos Landrace se detectaron efectos del tratamiento sobre las variables: rendimiento en canal, merma por enfriamiento y profundidad de grasa a nivel de la 1Oa costilla (P <.05). Las canales de cerdos Landrace, tratados con Olaquindox exhibieron una menor cobertura de grasa en la chuleta con relación al ZL y al testigo, y mostraron una menor merma por enfriamiento con el tratamiento de ZL. Para la raza Yorkshire no se observaron efectos sobre variables de la canal intacta (P > .05), pero en el despiece, se observaron efectos significativos del tratamiento, donde canales de animales implantados con DES rindieron menos cortes grasos. El sexo afectó en Landrace características cuantitativas como área del Longissímus, profundidad de grasa y rendimiento calculado de cortes magros; observándose en las hembras mayores rendimientos en cortes magros y menores rendimientos en cortes grasos que en machos castrados (P .05). Las variables del despiece americano y criollo mostraron en general un mayor rendimiento de cortes magros en las hembras.
Palabras claves: Implantes, olaquindox, sexo, canal, cerdos.
ABSTRACT
Fifty-four purebred (73 day-old, 21 Kg liveweigh0 and
Yorkshire (55 day-old, 12 Kg liveweight) pigs were randomly assigned from uniform breed, litter and weight groups of barrows and gilts to four different treatments consisting on: DES = Stilbestrol 15 mg implant; ZI- ~ Zeranol 12 mg implant; OX = feed with Olaquindox 50 ppm and 25 ppm until 45 and 100 Kg liveweight, respectively and C = control. Pigs were slaughtered at 100 ± 3 Kg final weight. Carcass cutting was achieved by use of american standard procedures and a local "Creole" method. Least square analysis of variance was performed for each breed including treatment, sex and treatment x sex interaction as main affects and initial weight as covariable. Landrace carcass study showed in ZL lower dressing percentage and shrink than C and OX. OX Landrace carcasses had thinner fat depth at 1/4 the length of longitudinal axis of loin eye muscle than ZL and C. Carcass study on Yorkshire groups demonstrated that DES produced lighter "Crecíle" jawIs than OX (P < -05). Landrace gilts as compared to barrows, had thinner (P <".05) fat depth, larger (P <.05) longissimus area, heavier (P < .05) weight of "Creole" ham, higher (P < .05) weight and percentage of american loin and fatback and lighter (P < .05) weight of total fat cuts per day of age. Carcasses from Yorkshire gilts yielded 0.74% more picnic shoulder and only 0.12% less boston butt (P < .05) than barrows, which in turn, yielded 1.0 Kg more of belly+jowl combined cuts, 3.64% more fat cuts of carcass weight and 2.96% more fat cuts of liveweight. Treatment x sex interaction revealed effects (P < .05) on weight and percentage of Landrace carcasses on "Creole" cutting method by changing the expected trend of lean: fat ratio in sexes. In Yorkshire carcass study, treatment x sex interaction affected (P < .05) back fat thickness and prediction of lean cuts. Reduction effects of promoters on fat items need to be revised in regard to physiological responses of sex and breed.
Key words: Implants, olaquindox, sex, carcass, swine.