O Status gestacional altera a qualidade da carne de novilhas zebuínas?

Abstract

We tested the hypothesis that physiological conditions during pregnancy change the meat quality of Zebu heifers. Thus, the objective of this study was to evaluate the qualitative attributes of meat from non-pregnant and pregnant Zebu heifers at different stages of pregnancy. Meat sample was collected from non-pregnant and pregnant heifers, classified according to the size of the fetus, in gestational thirds. Treatments were designed according to incomplete block design, with four treatments and twenty replicates, distributed as follows: I) Non-pregnant heifers; II) Pregnant heifers first third (fetus less than 16 cm), III) Pregnant heifers second third (fetus between 17 to 54 cm) and IV) (Pregnant heifers third third (fetus above 54 cm). After the animal’s bleed teething was evaluated and those with zero or two permanent incisor teeth were able to collect. The uterus was evaluated for pregnancy confirmation, and in the case of pregnant, fetus were measured from the upper end of the skull to the first coccygeal vertebra. Samples of the Longissimus dorsi muscle were taken between the 11th and 13th meat of pregnant and non-pregnant heifers. Heifers slaughtered in the second gestational third had a higher pH than non-pregnant heifers (P <0.05). Pregnant females increased the shear force and decreased the myofibrillar fragmentation index according to the increase in the size of the fetus (P <0.05). The content of ether extract in Longissimus dorsi decreased with advancing pregnancy (P <0.05). Higher shear strength was also observed for non-pregnant heifers compared to pregnant women in the first third and lower than pregnant in the third. Heifers gestating fetus larger than 54 cm have tougher meat with less fat content. However, the other qualitative attributes of the carcass and meat are not altered by pregnancy. Heifers in the early third of gestation have softer meat than nonpregnant heifers.