Marcelo Vedovatto

The objective of this experiment was to evaluate the effects of a prepartum trace mineral injection (TMI) in Brangus cows on the growth, physiology, and liver transcriptomic profile of their offspring. At 114 days prepartum (day −114), 40 cows [body weight (BW) = 533 ± 55] were assigned to either 1) Saline (saline solution, 0.9% NaCl; n = 20) or 2) TMI (solution containing 60, 10, 5, and 15 mg/ml of Zn, Mn, Se, and Cu, respectively; n = 20) administered subcutaneously (1 ml/90 kg BW in each cow). For the maternal results, the serum total protein concentration was lower ( p = 0.05) on day 1 (24 h postpartum) and day 80 in 0TMI vs . Saline cows. TMI did not affect ( p ≥ 0.11) the BW, body condition score, liver mineral concentration, other serum biochemistry variables, or serum insulin in cows. The offspring results showed that the BW tended to be greater ( p = 0.10) on days 80 and 157 in TMI vs . Saline calves. The serum concentrations of insulin, globulin, total protein, and creatinine were greater ( p ≤ 0.05) on day 1 in TMI vs . Saline calves. Furthermore, the serum albumin and glucose concentrations were greater ( p ≤ 0.05) in TMI vs . Saline calves, independently of the day. Liver genes related to immune response were differentially expressed ( ISG15 , MX1 , HERC6 , and OAS1Y ; p ≤ 0.05) in TMI vs . Saline calves. Thus, prepartum TMI tended to increase BW, affect the circulating metabolite concentrations, and alter the expression of the liver genes associated with the immune system in the offspring.

The use of copaiba oil (COP) in ruminant nutrition is relatively recent, and the results reported in the literature remain controversial. This study evaluated the effects of increasing dietary concentrations of COP on ruminal fermentation in steers. Five rumen-cannulated steers were assigned to a 5 × 5 Latin square design and received the following treatments: Control (0 g kg⁻¹ of COP), 1.25 g kg⁻¹ COP, 2.50 g kg⁻¹ COP, and 3.75 g kg⁻¹ COP dry matter (DM), and monensin (positive control; 40 mg kg⁻¹ DM in the concentrate). Animals were fed a 50:50 forage:concentrate diet. Copaiba oil supplementation (1.25 to 3.75 g kg⁻¹ DM) did not affect ruminal pH, the concentrations of NH₃-N, or propionate (mmol L⁻¹; p > 0.05). Similarly, COP had no effect on intake or nutrient digestibility (p > 0.05). In contrast, monensin increased (p ≤ 0.05) the concentrations of NH₃-N and propionate (mmol L⁻¹). Overall, COP supplementation did not modify ruminal fermentation under the conditions of this study. However, further studies are needed to assess its effects in diets with higher forage proportions, which better represent grazing systems.

The use of copaiba oil (COP) in ruminant nutrition is relatively recent, and results reported in the literature are still controversial. This study evaluated the effects of different concentrations of copaiba oil in the diet of steers on ruminal fermentation. Five rumen-cannulated steers were assigned to a 5 x 5 Latin square design and subjected to the following treatments: Control – (0 g of COP), 1.25 g COP, 2.50 COP, and 3.75 g COP kg^-1 dry matter (DM), and monensin (positive control - concentrate containing 40 mg kg^-1 DM). Animals were fed a diet with a forage-to-concentrate ratio of 50:50. Inclusion of copaiba oil from 1.25 to 3.75 g kg^-1 did not alter ruminal pH, and the concentrations of NH₃-N and propionate (mmol L^-1) were similar among treatments (P > 0.05). Copaiba oil did not affect intake, digestibility, or propionate concentration (P > 0.05). Monensin increases (P ≤ 0.05) the concentrations of NH3-N and propionate (mmol L^-1). Different concentrations of copaiba oil (Copaifera spp.) in the diet of steers did not affect ruminal fermentation. However, additional studies are needed to evaluate the inclusion of COP in diets with a higher forage proportion, better representing grazing conditions with predominant forage intake.

The objective of this study was to evaluate body development, growth performance, ingestive behavior, and physiological responses of Nelore and crossbred calves during the cow‐calf phase. Thirty beef calves were divided into four groups according to their genotype: Nelore (NE; eight animals), Nelore × Senepol (NS; eight animals), Nelore × Montana (NM; six animals), and Tricross (TC; eight animals; ¼ Nelore × ¼ Senepol × ½ Angus and ¼ Nelore × ¼ Montana × ½ Angus). NE calves exhibited greater body height than those of the other genetic groups ( P < 0.05), which, in turn, did not differ from one another. Regarding average daily gain, NE animals had lower values than those observed in the other genetic groups ( P < 0.05). The TC calves spent less time grazing than the calves in the other genetic groups ( P < 0.01), which did not differ from each other. Regarding skin color, L ^* values were lower in NE calves than in NS and NM calves ( P = 0.04). Crossbreeding of Nelore with taurine breeds shows potential to improve productivity while maintaining adaptability during the preweaning phase.

The present study aimed to evaluate whether the inclusion of curcumin as a performance enhancer in finishing cattle has positive effects on animal production, the ruminal environment, hematological and biochemical markers, as well as meat quality. Sixteen castrated Holstein steers, 8 months of age, with an average body weight of 247 ± 3.89 kg were divided into two groups: Control, consisting of animals that consumed 144 mg of monensin/animal/day (n = 8); Treatment, consisting of animals that consumed 552 mg of curcumin/animal/day (n = 8). Animals were fed a diet containing 44% roughage (corn silage) and 56% concentrate for 105 days. During this period, body weight measurements were recorded, and blood samples were collected for the determination of hematological, biochemical, and immunological variables. At the end of the experimental period, animals were slaughtered and meat samples were collected for evaluation. No differences were observed between groups for animal performance, feed intake, or feed efficiency. A lower leukocyte count (lymphocyte and granulocyte) and a higher platelet count were observed in animals that consumed curcumin. These animals also exhibited higher cholesterol levels, along with lower circulating glucose concentrations compared to the control group. In the ruminal environment, higher bacterial activity and greater protozoal counts were observed in the treatment group, but no effects on ruminal short-chain fatty acids were observed. Higher activity of the enzymes glutathione S-transferase in serum and superoxide dismutase in meat was observed, combined with lower lipid peroxidation in serum and meat. Meat from steers fed curcumin showed greater yellow color intensity, higher water-holding capacity, and a higher proportion of monounsaturated fatty acids compared to the control group. These results suggest that curcumin can be used as a performance enhancer, similar to monensin, when thinking about performance, but beyond that, curcumin triggered anti-inflammatory and antioxidant action.

Two experiments evaluated the effects of copper (Cu) and zinc (Zn) injection on body weight (BW), body condition score (BCS), pregnancy rate, ovarian traits, and antioxidant and inflammatory responses of beef heifers. In Exp. 1, 29 heifers were assigned to having saline or CuZn (a solution containing 15 and 50 mg/mL of Cu and Zn) subcutaneously injected (5 mL/heifer) 9 days before artificial insemination. Exp. 2 was conducted to increase the statistical power to evaluate pregnancy rate, and 283 heifers were assigned to either the saline or CuZn group. In Exp. 1, CuZn heifers tended (p ≤ 0.10) to gain more BW and to have greater corpus luteum size and plasma concentration of glutathione peroxidase. No effects of treatment were detected (p ≥ 0.18) for BCS; estrus score; serum concentration of Cu, Zn, and cortisol; and plasma concentration of haptoglobin, ceruloplasmin, and superoxide dismutase. In Exp. 2, CuZn heifers had greater (p < 0.01) BW and serum Cu. The CuZn heifers with low BCS had greater (p ≤ 0.05) estrus scores and tended (p = 0.10) to have greater pregnancy rates. Thus, injecting CuZn may be an effective strategy to enhance growth, reproductive performance, and antioxidant responses in heifers, especially when their BCS is below 5.

This experiment evaluated the effects of a nose flap (NF) device and bovine-appeasing substance (BAS) administration on the growth, temperament, immune response, and pasture behavior of calves during weaning. A total of 24 Nellore calves were used in a 2 × 2 factorial arrangement. The factors were the use of an NF or not (NoNF) for 14 d before weaning and the administration of BASs or not (NoBAS) at weaning (d 0). NF vs. NoNF reduced (p ≤ 0.01) the average daily gain (ADG; d −7 to 84; −0.289 vs. 0.378 ± 0.13 kg/d) and the time ruminating but increased (p ≤ 0.05) the exit score from the chute (d 14 and 28) and the time grazing. BAS vs. NoBAS administration increased (p ≤ 0.02) the ADG (d 14 to 84; 0.487 vs. −0.08 ± 0.10 kg/d) and the time grazing, reduced (p < 0.01) the time ruminating, and tended to decrease (p ≤ 0.10) the exit score (d 7, 14 and 28) and the time vocalizing. Treatments did not affect (p ≥ 0.35) serum rabies titer concentration. Thus, the use of NFs reduced growth and increased stress after weaning, while BAS administration increased growth and decreased stress after weaning, altering behavior but not the immune system. According to the results of this experiment, the use of BASs but not NFs is recommended to alleviate weaning stress in beef calves.

The aim of this study was to evaluate the effects of different levels of black sucupira oil (Bowdichia virgilioides Kunth) on nutrient intake, digestibility, rumen variables, and serum biochemistry. Four cannulated crossbred steers [body weight (BW) 450 ± 20 kg] were assigned to a 4 × 4 Latin square design with the treatments: (1) control (CON), without oil; (2) inclusion of 1.25 g oil seed (OS) kg-¹ of dry matter (DM); (3) inclusion of 2.5 g OS kg^-1 of DM; and (4) inclusion of 3.75 g OS kg^-1 of DM. Results showed no significant effect (P > 0.05) of black sucupira oil seed on rumen pH and N-NH₃ levels. However, the inclusion of 2.5 g OS in the diets significantly decreased (P ≤ 0.05) crude protein (CP) and DM digestibility. Differences were noted in the concentrations of isobutyric acid (0.67, 0.81, 0.71, 0.80 mmol L^-1) and isovaleric acid (0.91, 1.14, 1.21, 1.11 mmol L^-1), as well as total volatile fatty acids released in the rumen with OS inclusion. Sampling time significantly affected (P ≤ 0.05) rumen pH and N-NH₃. Thus, it can be concluded that black sucupira seed oil decreases CP intake and digestibility, acting as a temporary nutritional modulator in beef cattle diets.