João Gustavo Weschenfelder Wandscheer

The use of crossbreeding between dairy and beef breeds has been adopted as a strategy to add value to male calves from dairy systems, improve productive efficiency, and reduce economic and animal welfare concerns. This study evaluated the effects of Holstein × Angus crossbreeding on productive performance, metabolism, ruminal fermentation, nutrient digestibility, carcass characteristics, meat quality, and fatty acid profile during the feedlot finishing phase. Twenty-four uncastrated male cattle (8 Holstein, 8 Angus, and 8 crossbreds) were confined for 130 days and fed an isoenergetic and isonitrogenous diet. No significant differences were observed among breeds for weight gain, dry matter intake, feed efficiency, or nutrient digestibility (p > 0.05). However, Angus and crossbred cattle showed higher carcass yield compared to Holstein cattle (p ≤ 0.05). Angus and crossbred animals presented higher concentrations of total volatile fatty acids, acetate, and propionate in the rumen (p ≤ 0.05). Breed differences were also observed in erythrocyte indices and serum urea concentrations (p ≤ 0.05). Meat from crossbred animals showed superior quality attributes compared to Holstein, including lower ultimate pH, higher lightness, greater water-holding capacity, and an intermediate lipid profile between the parental breeds (p ≤ 0.05). It is concluded that Holstein × Angus crossbreeding improves carcass yield, ruminal fermentation efficiency, and meat quality, without compromising productive performance, representing a viable strategy for adding value to male calves from dairy herds under tropical production conditions.

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.

The study evaluated whether organic chromium supplementation in the diets of Jersey cows in the final third of lactation has positive effects on productive performance and milk quality, as well as markers of metabolism, hematology, immunological, and oxidative response. We used 22 cows in a 56-day study, divided into two groups: control (n = 11) and chromium treatment at 10 mg/kg of dry matter per day (n = 11). We evaluated these animals’ productive performance markers (milk production, feed intake, and lactation persistence), milk quality (composition and somatic cell counts), and blood biomarkers to assess animal health. Chromium concentration at the beginning of the experiment was within normal limits for the animal category (221 to 246 nM). The cows’ consumption of organic chromium increased its bioavailability in the body, with higher concentration in the serum (p = 0.01) and milk (p = 0.013) of Jersey cows compared to the control cows. Supplementing cows with chromium resulted in higher fat-corrected milk production (p = 0.05), longer lactation persistence (p = 0.05), and feed efficiency (p = 0.02) compared to the control group. There was a lower SCC (p = 0.01) on days 28, 42, and 56, as well as a higher percentage of fat in the milk of supplemented cows on days 28 and 42 compared to that of the control group (p = 0.01). As a treatment effect (p ≤ 0.05), we found cows supplemented with chromium had a higher concentration of insulin, immunoglobulin G, and creatine kinase activity dismutase compared to control animals. Considering the treatment × day interaction (p ≤ 0.05), we observed greater activity of the creatine kinase enzymes (days 14, 28, and 56), as well as lower cholinesterase activity (days 42 and 56) compared to those of the control. The concentration of globulins (p = 0.05) and immunoglobulin G (p = 0.01) on day 56 was higher in cows that consumed chromium. Higher superoxide dismutase activity on days 42 and 56 (p = 0.04) was observed in the blood of cows supplemented with organic chromium compared to that of the control. Therefore, we conclude that the addition of organic chromium was beneficial to maintaining lactation persistence and increasing fat-corrected milk production.

Background: This experiment evaluated whether the combination of essential oils (thyme, rosemary, orange) with extracts of Cinnamomum and Quillaja saponaria (enriched with tocopherols) in steers’ diet has positive effects on the health, digestibility, growth, oxidative stress, and fatty acid profile of meat. Methods: The experiment included 24 Holstein steers, divided into two groups, randomly divided (treated = phytogenic mixture (n = 12); control = monensin (n = 12)), undergoing a growth phase of 120 days and 90 days of finishing in individual pens, with a monthly collection of blood, rumen fluid, feces, and feed. Results: In the finishing phase (days 150 to 210), there was a tendency (p = 0.07) toward more significant average daily weight gain when cattle consumed a phytogenic mixture than monensin. The use of the phytogenic product showed greater feed efficiency in the period from 150 to 240 days (p < 0.05), with higher levels of short-chain fatty acids (SCFAs), without differences in the composition of these SCFAs between the control and treated groups, with a reduction in apparent digestibility in the treated group. In blood parameters, the treated group showed higher erythrocyte counts (p < 0.05) without changes in leukocytes, lymphocytes, granulocytes, monocytes, and platelets. The phytogenic treatment demonstrated higher total protein and globulin levels, with increased glucose levels on days 30 and 210 (p < 0.05). Ceruloplasmin and haptoglobin levels increased in the treated group without changes in ferritin, transferrin, C-reactive protein, IgA, and heavy-chain immunoglobulins (p < 0.05). A reduction in oxidative stress was observed using the phytogenic agent, with a marked decrease in the levels of reactive oxygen species (ROS) and carbonyl proteins, with a tendency to increase glutathione S-transferase (p < 0.05). In meat, the phytogenic reduced saturated fatty acids with increased polyunsaturated fatty acids and increased the omega 6/omega 3 ratio. Lower levels of thiobarbituric acid reactive substances and ROS were detected in the meat combined with a higher concentration of total thiols in the treated group than in the control group. Conclusions: The use of the phytogenic in steers’ diets has shown to be a viable candidate for replacing monensin, presenting equal or superior performance results with systemic modulating effects on oxidative stress, meat quality, and serum and biochemical parameters that contribute to more substantial health and efficiency.