This study examined the effects of injectable vitamin C (VC) before transport and duration of transit on feedlot performance, inflammation, and muscle fatigue in cattle. One hundred thirty-two Angus-cross steers (393 ± 4 kg) were stratified by body weight (BW) to a 2 × 2 factorial of intramuscular injection (INJ; 20 mL/steer): VC (250 mg sodium ascorbate/mL) or saline (SAL) and road transit duration (DUR): 18 h (18-h; 1,770 km) or 8 h (8-h; 727 km). On d 0, steers were weighed and given INJ of VC or SAL immediately before transport. Upon return (d 1), BW and blood were collected before steers returned to pens equipped with GrowSafe bunks. Steers were weighed on d 0, 1, 7, 15, 30, 31, 54, and 55. Data were analyzed via ProcMixed of SAS (experimental unit = steer; 32 to 34 steers/treatment) with fixed effects of INJ, DUR, and the interaction. Blood was collected on d -5, 1, 2, 3, and 7 (n = 9 steers/treatment); blood parameters were analyzed as repeated measures with the repeated effect of day. Area under the curve (AUC) for plasma ferric reducing antioxidant power (FRAP) was calculated using R. Final BW was greater for 8-h compared to 18-h (P = 0.05) with no effect of INJ or interaction (P ≥ 0.51). Dry matter intake (DMI) from d 1 to 7 was greater for VC-8, intermediate for VC-18 and SAL-18, and least for SAL-8 (P = 0.02). Overall DMI tended to be greatest for SAL-18, intermediate for VC-18 and VC-8, and lowest by least for SAL-8 (P = 0.08). Day 7 to 31 gain:feed (G:F) was greatest for VC-18 compared to other treatments (INJ × DUR, P = 0.05), and there was no effect of treatment on overall G:F (P ≥ 0. 19). There was no INJ or INJ × DAY (P ≥ 0.17) effect on serum lactate, haptoglobin, or non-esterified fatty acid. However, these blood parameters were greater on d 1 for 18-h compared to 8-h, and both treatments returned to near baseline by d 3 (DUR × DAY, P < 0.01). Plasma ascorbate concentrations on d 1 were greater for VC compared to SAL and returned to baseline by d 2 (INJ × DAY, P < 0.01). Plasma FRAP AUC from d -5 to 3 was greatest for VC-18, intermediate for VC-8 and SAL-8, and lowest by least for SAL-18 (INJ × DAY, P = 0.02). This suggests an antioxidant prior to long-haul transit positively influenced antioxidant capacity; however, VC did not improve overall post-transit performance. While longer transit duration increased indicators of muscle fatigue and inflammation, post-transit performance was not appreciably different between transit durations.

The objective was to determine the effects of injectable vitamin E (VE) before or after transit on feedlot cattle receiving performance, health, and blood parameters. Angus × Simmental steers (n = 196; body weight [BW] = 163 ± 29 kg) were utilized in a randomized complete block design. Steers were blocked by BW and randomly assigned to 1 of 3 treatments: intramuscular injections of saline pre- and post-transit (CON), intramuscular injections of VE (2,000 mg d-α-tocopherol) pre-transit and saline post-transit (PRE), or intramuscular injections of saline pre-transit and VE (2,000 mg d-α-tocopherol) post-transit (POST). Pre-transit injections were administered on day 0, and steers were transported on day 7 for approximately 4 h (348 km). After arrival, steers were fed a common corn silage-based diet in GrowSafe bunks. Final BW tended to be greater (P = 0.08) for CON steers compared with POST steers while PRE steers were intermediate. From days 7 to 63, treatment affected average daily gain (ADG) with PRE and CON steers exhibiting (P = 0.04) greater ADG compared with POST steers. Dry matter intake (DMI), water intake, and gain to feed from days 7 to 63 were not affected (P ≥ 0.17) by treatment. Day 0 serum α-tocopherol concentrations were considered marginal (2.3 ± 0.2 mg/l). A treatment × day interaction (P < 0.01) was observed for serum α-tocopherol concentrations. Serum α-tocopherol concentrations were greatest for PRE steers on day 7 (prior to and post-transit), but greater for POST steers on dys 10 and 14. Plasma ferric-reducing antioxidant potential concentrations increased (P = 0.04) for POST steers compared with CON steers and PRE steers being intermediate. Plasma non-esterified fatty acids (NEFA) concentrations exhibited a treatment × day interaction (P = 0.04) with CON and POST steers being 16% and 14% greater than PRE steers on day 14, respectively. On day 21, NEFA concentrations were greatest for POST steers compared with PRE steers and CON steers being intermediate. There was no main effect (P ≥ 0.14) of treatment on the number of bovine respiratory disease morbidity treatments. Hair cortisol concentrations were decreased (P < 0.01) 14 days after transit for PRE and POST steers compared with CON steers. Overall, injectable VE administered before or after transit increased serum tocopherol concentrations while reducing stress, but did not improve the growth performance of beef steers during the receiving phase.

This study examined the effects of injectable vitamin C (VC) before transport and duration of transit on feedlot performance, inflammation, and muscle fatigue in cattle. One hundred thirty-one, Angus-cross steers (409 ± 4 kg) were stratified by bodyweight (BW) to a 2 × 2 factorial of intramuscular injection (INJ; 20 mL/steer): VC (250 mg sodium ascorbate/mL) or saline (SAL) and road transit duration (DUR): 18 (18; 1,770 km) or 8 h (8; 727 km). On d 0, steers were weighed and received INJ of SAL or VC immediately before transport. Upon return (d 1), BW and blood were collected before steers returned to pens with GrowSafe bunks. Steers were weighed on d 0, 1, 7, 15, 30, 31, 54, and 55. Data were analyzed via ProcMixed of SAS (experimental unit = steer; 32–34 steers/treatment) with fixed effects of INJ, DUR, and the interaction. Blood was collected on d -5, 1, 2, and 3 (9 steers/treatment); blood parameters were analyzed as repeated measures. Average daily gain (ADG) and BW were greater on d 7 and 15 for SAL-18 compared to all other treatments (INJ × DUR, P < 0.01). Final BW, overall ADG, and gain:feed were greater for 18 than 8 (P < 0.01). Injection did not affect BW (P > 0.13) but VC decreased overall dry matter intake compared to SAL (P = 0.03). Steers transported for 18 h had greater serum lactate, haptoglobin, and non-esterified fatty acid concentrations on d 1 compared to steers transported for 8 h (DUR × DAY, P < 0.01). Day 1 plasma ascorbate concentrations were greater for VC and returned to baseline concentrations by d 2 (INJ × DAY, P < 0.01). In contrast to previous work, VC did not improve post-transit performance; however, longer transit duration increased indicators of muscle fatigue and inflammation.

The objective of these experiments was to assess the effects of food and water deprivation and transit duration on the behavior of beef feedlot steers. In Experiment 1, 36 Angus-cross steers (353 ± 10 kg) were stratified to six pens and assigned one of three treatments (n = 12 steers/treatment): control (CON; stayed in home pens with ad libitum access to feed and water), deprived (DEPR; stayed in home pens but deprived of feed and water for 18 h), or transported (TRANS; subjected to 18-h transit event and returned to home pens). In Experiment 2, 60 Angus-cross steers (398 ± 5 kg; 6 steers/pen) were transported either 8 (8H) or 18 (18H) h. Four 8H pens (n = 24 steers) and six 18H pens (n = 36 steers) were used for behavioral analysis. In both experiments, the time to eat, drink, and lay down was recorded for each steer upon return to home pens. Total pen displacements from the feed bunk were also assessed for the two hours following feed access in both experiments. Data were analyzed using Proc Mixed of SAS 9.4, with treatment as a fixed effect. Steer was the experimental unit for behavioral activities, while pen was the experimental unit for bunk displacements. Displacements were analyzed as repeated measures with the repeated variable of time. In Experiment 1, time to eat and drink was similar across treatments (P ≥ 0.17). However, TRANS laid down in 16.5 min while DEPR did not lay down until 70.5 min post-arrival to pen (P < 0.01). Deprived steers had greater bunk displacements in the first 70 min post-feed access than CON or TRANS, though displacements among treatments from 100 to 120 min post-feed access were similar (Treatment × Time: P = 0.02). In Experiment 2, both 8H and 18H steers laid down approximately 25 min post-home pen arrival (P = 0.14). There was no effect of transit duration or duration by time on bunk displacements (P ≥ 0.20), though displacements were greater from 0 to 20 min than from 20 to 30 min post-feed access (Time: P = 0.04). Steers that were deprived of feed and water were highly motivated to access those resources, while transported steers prioritized laying down. Producers should consider these priorities when preparing to receive cattle from a long transit event.

To assess efficacy of bis-glycinate bound Zn, 36 crossbred wethers (34 ± 2 kg) were sorted by body weight into three groups and stagger started on a Zn deficient diet (18 mg Zn/kg dry matter; 22.5% neutral detergent fiber) for 45 d prior to a 15-d metabolism period (10 d adaptation, 5 d collection). On d 46, lambs were randomly assigned to dietary treatments (4 lambs treatment-1group -1): no supplemental Zn (CON) or 15 mg supplemental Zn/kg dry matter (ZINC) as Zn sulfate (ZS) or bis-glycinate (GLY; Plexomin Zn, Phytobiotics). Blood was collected from all lambs on d 1, 44, 56, and 61. Liver, jejunum, and longissimus dorsi samples were collected after euthanasia on d 61. Gene expression was determined via quantitative real-time polymerase chain reaction. Data were analyzed using ProcMixed of SAS (experimental unit = lamb; fixed effects = treatment, group, and breed) and contrast statements assessed the effects of supplemental Zn concentration (ZINC vs. CON) and source (GLY vs. ZS). After 15 d of Zn supplementation, plasma Zn concentrations were greater for ZINC vs. CON and GLY vs. ZS (P ≤ 0.01); tissue Zn concentrations were unaffected (P ≥ 0.27). Liver Cu concentrations were lesser for ZINC vs. CON (P = 0.03). Longissimus dorsi Mn concentrations were greater for ZINC vs. CON (P = 0.05) and tended to be lesser for GLY vs. ZS (P = 0.09). Digestibility of DM, OM, and NDF was lesser for ZINC vs. CON (P ≤ 0.05); ADF digestibility tended to be greater for GLY vs. ZS (P = 0.06). Nitrogen retention (g/d) tended to be greater for GLY vs. ZS (P = 0.10) and N apparent absorption was lesser for ZINC vs. CON (P = 0.02). Zinc intake, fecal output, retention, and apparent absorption were greater for ZINC vs. CON (P ≤ 0.01). Apparent absorption of Zn was -5.1, 12.8, and 15.0% for CON, ZS, and GLY, respectively. Nitrogen and Zn retention and apparent absorption were not correlated for CON (P ≥ 0.14) but were positively correlated for ZINC (retention P = 0.02, r = 0.52; apparent absorption P < 0.01, r = 0.73). Intestinal expression of Zn transporter ZIP4 was lesser for ZINC vs. CON (P = 0.02). Liver expression of metallothionein-1 (MT1) tended to be greater for GLY vs. ZS (P = 0.07). Although Zn apparent absorption did not differ between sources (P = 0.71), differences in post-absorptive metabolism may be responsible for greater plasma Zn concentrations and liver MT1 expression for GLY supplemented lambs, suggesting improved bioavailability of GLY relative to ZS.