The objective of this research was to evaluate the biochemical and hormonal parameters of Santa Inês sheep that received diets with different levels of guava agro-industrial waste (GAW). Forty non-castrated male animals of the Santa Inês breed were used, with an average initial weight of 21.3 ± 2.6 kg, and an average age of 120 days. The animals were distributed in a completely randomized design, with five treatments and eight replicates, and fed with increasing GAW levels replacing hay (0.0, 7.5, 15.0, 22.5 and 30.0%). After the beginning of the diet period, blood samples were collected every 2 weeks approximately 3 h after feeding. Cholesterol concentration had a significant effect (P < 0.01) with the inclusion of GAW. The animals that ingested the control diet had the highest concentrations of cholesterol. T3 and T4 hormones showed a significant difference (P < 0.01) among the treatments, i.e. the animals that ingested the control diet had the lowest concentrations of these hormones. We concluded that the inclusion of GAW in up to 30% decreases the concentration of cholesterol and increases the concentrations of T3 and T4 in the blood, aiding the metabolism of the animals.
Keywords: By-product; Cholesterol; Cortisol; Sheep; T3; T4.