RESUMEN
To investigate effects of inorganic or complexed trace mineral source (zinc, copper, manganese, and cobalt) on receiving period performance and morbidity, crossbred beef heifer calves (nâ =â 287) arriving on three delivery dates were used in a 42-d receiving trial. Heifers were processed after arrival, stratified by day -1 body weights (BW) and allocated randomly to eight pens (11 to 13 heifers/pen, 24 pens total). Within truckload, pens were assigned randomly to dietary treatment (nâ =â 12 pens/treatment). Heifers were housed on 0.42-ha grass paddocks, provided ad libitum bermudagrass hay and provided dietary treatments in grain supplements fed daily. Treatments consisted of supplemental zinc (360 mg/d), copper (125 mg/d), manganese (200 mg/d), and cobalt (12 mg/d) from complexed (Zinpro Availa 4, Zinpro Corp. Eden Prairie, MN) or inorganic sources (sulfates). Heifers were observed daily for clinical bovine respiratory disease (BRD). If presenting BRD symptoms and rectal temperatureâ ≥â 40 °C, heifers were deemed morbid and treated with antibiotics. Six heifers/pen were bled to determine serum haptoglobin concentrations on days 0, 14, and 28. Liver biopsies were taken on day 5â ±â 2 and 43â ±â 1 from three calves selected randomly from each pen for mineral status comparisons. Statistical analyses were performed using the MIXED, GLIMMIX, and repeated measures procedures of SAS 9.4 with truckload as a random effect and pen within truckload specified as subject. There tended to be a treatment by day interaction for BW (Pâ =â 0.07). Heifer BW did not differ on day 0 (Pâ =â 0.82) and day 14 (Pâ =â 0.36), but heifers fed complexed trace minerals had greater BW on day 28 (Pâ =â 0.04) and day 42 (Pâ =â 0.05). Overall average daily gains were greater for heifers fed complexed trace minerals (Pâ =â 0.05; 0.78 vs. 0.70 kg, SEâ =â 0.03). Heifers supplemented with inorganic trace minerals had greater BRD incidence (Pâ =â 0.03; 58 vs. 46%, SEâ =â 3.6). Haptoglobin concentrations decreased throughout the trial (Pâ <â 0.001), and heifers fed complexed trace minerals tended to have a decrease in haptoglobin concentrations (Pâ =â 0.07). The source of trace mineral supplementation had no effect (Pâ ≥â 0.20) on liver mineral concentrations and there were no treatmentâ ×â day interactions (Pâ ≥â 0.35). In conclusion, supplementing diets for the first 42 d after arrival with complexed trace mineral sources improved heifer performance as compared to heifers supplemented with inorganic trace minerals.
Issues associated with health and management of newly received cattle continue to pose significant animal welfare and economic challenges for the beef industry. Diagnosis of bovine respiratory disease, accompanied with poor growth performance, can be addressed by nutritional intervention in receiving cattle. Trace mineral inclusion in receiving rations is vital to calf performance. There are numerous sources of trace mineral supplements that exist commercially for cattle and their effects on immune function, growth, and performance measures were evaluated. Organic trace mineral supplements are being used in replacement of inorganic salts due to potentially greater bioavailability and functionality. An organic source that is commonly used are amino acid complexes. Replacing inorganic sources with complexed sources of trace minerals (zinc, copper, manganese, and cobalt) improved growth performance and decreased sickness during the 42-d receiving study.
Asunto(s)
Oligoelementos , Bovinos , Animales , Femenino , Oligoelementos/farmacología , Manganeso/farmacología , Cobre/farmacología , Haptoglobinas/análisis , Suplementos Dietéticos , Minerales/farmacología , Zinc/farmacología , Cobalto/farmacología , Dieta/veterinaria , Peso Corporal , Alimentación Animal/análisisRESUMEN
Supplementing trace minerals is common in managing bovine respiratory disease (BRD) in post-weaned cattle; however, its influence on host immunity and metabolism in high-risk cattle remains unclear. We aimed to assess the impact of three supplementation programs on liver and serum trace element concentrations and blood gene expression. Fifty-six high-risk beef steers were randomly assigned to one of three groups over 60 days: (1) sulfate-sourced Cu, Co, Mn, and Zn (INR), (2) amino acid-complexed Cu, Mn, Co, and Zn (AAC), or (3) AAC plus trace mineral and vitamin drench (COMBO). Serum and liver biopsies for Cu, Co, Mn, and Zn at d0, d28, and d60 were analyzed from cattle free of BRD (n = 9 INR; n = 6 AAC; n = 10 COMBO). Differences and correlations of mineral concentrations were analyzed via generalized linear mixed models and Spearman's rank coefficients, respectively (p < 0.05). Whole blood RNA samples from healthy cattle (n = 4 INR; n = 4 AAC; n = 4 COMBO) at d0, d13, d28, d45, and d60 were sequenced and analyzed for differentially expressed genes (DEGs) via glmmSeq (FDR < 0.05), edgeR (FDR < 0.10), and Trendy (p < 0.10). Serum and liver Cu and Co concentrations increased over time in all groups, with higher liver Cu in COMBO (487.985 µg/g) versus AAC (392.043 µg/g) at d60 (p = 0.013). Serum and liver Cu concentrations (ρ = 0.579, p = 6.59 × 10-8) and serum and liver Co concentrations (ρ = 0.466, p = 2.80 × 10-5) were linearly correlated. Minimal gene expression differences were found between AAC versus COMBO (n = 2 DEGs) and INR versus COMBO (n = 0 DEGs) over time. AAC versus INR revealed 107 DEGs (d13-d60) with increased traits in AAC including metabolism of carbohydrates/fat-soluble vitamins, antigen presentation, ATPase activity, and B- and T-cell activation, while osteoclast differentiation and neutrophil degranulation decreased in AAC compared to INR. Our study identifies gene expression differences in high-risk cattle fed inorganic or amino acid-complexed mineral supplements, revealing adaptive immune and metabolic mechanisms that may be improved by organically sourced supplementation.