Suchergebnisse

This study was carried out to evaluate the influence of a synthetic progesterone ear implant on weight gain and meat quality of Nellore heifers. Twenty-eight Nellore heifers with an average initial weight of 240.9 kg were used in this experiment. All heifers received the same dietary management, in an intensive rearing system, with mineral salt and water ad libitum. Heifers were distributed, in a completely randomized design, into two treatments (with and without progesterone ear implant) with seven replications, in 14 stalls. Analysis of variance was performed, and, for non-parametric variables, the Kruskal-Wallis test was applied. Parameters referring to the meat quantitative and qualitative characteristics, represented by the weight and yield of the carcass, conformation, marbling, color, meat texture, carcass morphometric measurements, longissimus dorsi muscle area, and fat thickness, were not affected by the progesterone hormone. The use of the progesterone ear implant did not change the carcass physical characteristics or the meat quality characteristics.

The objective of this work was to compare the serum cortisol levels among four genetic cattle groups slaughtered in confinement. Thirty-two non-castrated male bovines from four genetic groups were analyzed: Nelore, Aberdeen Angus × Nelore, Caracu × Nelore, and Guzerá × Nelore. The blood samples were collected on the day of weighing (every 28 days) and during the slaughter. Regarding the concentration of serum cortisol, no significant differences were found among the groups during the first, second, and fourth collections. However, during the third collection and at the day of slaughter, respectively, the Nelore group (3.15 ng/dL; 2.98 ng/dL) showed similarity to the Caracu × Nelore (2.02 ng/dL; 2.07ng/dL) and Guzerá × Nelore (2.33 ng/dL; 2.40 ng/dL) groups. Nelore showed a significant difference compared with the Aberdeen Angus × Nelore group (1.21 ng/dL; 1.61 ng/dL). With respect to the overall collection averages, the Nelore group (2.85 ± 0.87 ng/dL) showed greater values than the Aberdeen Angus × Nelore group (1.61 ± 0.87 ng/dL). However, it showed similarities to the Caracu × Nelore (2.06 ± 1.31 ng/dL) and Guzerá × Nelore (2.48 ± 1.16 ng/dL) groups. It was also observed that animals with low cortisol values gained more weight, as demonstrated by the correlation between ADG and the cortisol collection averages (-0.54; p < 0.05). There was no difference among the groups with respect to shearing strength of the meat, and the correlation between this force and the cortisol collection average (0.15; p > 0.05, ns) showed that meat tenderness in the studied groups was not affected.

The quality of meat is influenced by several aspects, among which post-vaccination abscesses and bruises stand out as primary factors for the condemnation of carcasses. However, economic losses resulting from improper handling practices can severely compromise the profitability of both the packing plant and the producer. The objective of this study was to estimate the frequency of occurrence of abscesses and bruises in carcasses of animals slaughtered in a packing plant and analyze the economic losses generated by them. The number of animals examined was determined according to the slaughter flow in the packing plant (10-20% of animals/day). Data pertaining to region and number of bruises, abscess location, weight of excised portions and distance from the municipalities of origin of the animals were collected and evaluated by descriptive statistical analysis. The occurrence of lesions was 78% trauma- and 45% abscess-derived. The presence of these lesions resulted in economic losses, representing a depreciation of BRL 2.99/animal in the profit obtained by the cattle farmer. A comparison between the "sex classes" and "bruising" factors revealed that the females had higher occurrence and distribution of bruises and abscesses than uncastrated and castrated males. Bruises were more frequent in the hindquarter region, regardless of the distance, while abscesses were restricted to the forequarter. The weight of discarded tissues was higher on farms less than 200 km away from the packing plant; however, these results were influenced by the number of animals evaluated in the group.