No abstract

Experiments were conducted to determine digestibility of wet corn gluten feed in sheep and effect of wet corn gluten feed on DM intake, milk production, and milk composition by dairy cows. In Trial 1, six wethers were fed wet corn gluten feed at maintenance and ad libitum for determination of nutrient digestibility by the conventional 7-d total collection technique. The sheep ate 1.32 times maintenance at ad libitum intake and no significant differences were found in digestibility due to intake. Digestibilities of DM, organic matter, energy, CP, ether extract, ADF, NDF, and hemicellulose averaged 70.3, 73.0, 73.7, 78.3, 72.8, 51.4, 58.1, and 60.4%, respectively. Mean total digestible nutrients for both treatments was 70.3. In Trial 2, 12 Holstein cows in mid to late lactation were allotted to a 4 x 4 Latin square design. Cows were fed a total mixed ration twice daily. Wet corn gluten feed was fed at 0 (control), 10, 20, and 30% of the total ration DM. There were no significant treatment effects on DM intake, milk yield, or milk composition. Dry matter intake (kg/d), milk production (kg/d), and percent milk fat were 21.4, 22.9, and 3.71, respectively, for control; 21.4, 23.0, and 3.80 for the 10%; 21.0, 23.1, and 3.71 for the 20%; and 21.0, 23.2, and 3.89 for the 30% wet corn gluten feed.

The objective of this experiment was to evaluate the influence of an active live yeast direct-fed microbial (DFM) product on receiving and backgrounding period growth performance and efficiency of dietary net energy (NE) utilization in low health risk beef steers. Maine-Anjou × Angus steers (n = 199; body weight [BW] = 252 ± 32.1 kg) were received from two sources at the Ruminant Nutrition Center in Brookings, SD, in November 2019 and used in a 77-d feedlot receiving and backgrounding experiment. Steers were provided access to long-stem hay and ad libitum water upon arrival. Steers were weighed, vaccinated for respiratory pathogens (source 2 only): infectious bovine rhinotracheitis, bovine viral diarrhea types 1 and 2, parainfluenza-3 virus, and bovine respiratory syncytial virus (Bovi-Shield Gold 5, Zoetis, Parsippany, NJ) vaccinated for clostridial species (Ultrabac 7/Somubac, Zoetis) and pour-on moxidectin (Cydectin, Bayer, Shawnee Mission, KS). Steers (n = 176 steers; initial unshrunk BW = 235 ± 27.6 kg) were allotted to pens (n = 20 pens; 10 pens per treatment; eight or nine steers per pen). Diets were based upon corn silage, dry-rolled corn, and dried distillers grains; dietary treatments were 1) no DFM (CON) and 2) DFM (Levucell SC, Advantage Titan, CNCM l-1077), fed at 10 g/steer/d providing 8 × 109 CFU of active live yeast to each steer daily (DFM). Initial BW was the average of day −1 and day 1 BW (n = 176 steers; initial BW = 253 ± 27.6 kg). On day 21, steers received a 200-mg progesterone and 20-mg estradiol benzoate implant. Data were analyzed from day 1 to 47 (receiving period), day 48 to 77, and from day 1 to 77 as a randomized complete block design; pen served as the experimental unit for all analyses. On day 47 of the experiment, DFM had greater BW (P = 0.01) by 0.9% and average daily gain (ADG; P = 0.01) by 4.2% and gain-to-feed ratio (G:F) tended (P = 0.13) to be 2.8% greater. Day 77 BW did not differ (P = 0.60), cumulative (days 1–77): ADG (P = 0.47), dry matter intake (P = 0.66), and G:F (P = 0.56) were similar. Yeast inclusion had no appreciable influence on performance-based dietary NE utilization or the ratio of observed/expected dietary NE (P ≥ 0.59). In low health risk steers, DFM improved performance during the feedlot receiving period. However, no improvements for DFM were detected for cumulative performance from day 1 to 77. The confirmation of yeast counts indicated the CFU to be above the expected level at the start of the trial but was found below expected level at the end of the trial. This may explain differences during the initial 47 d compared to cumulative growth performance results.

Effects of daily sometribove administration on milk yield and composition, body condition score, BW, and SCC were evaluated in Holstein cows milked three times daily. Lactating cows (n =104) were assigned randomly to control or sometribove-treated (25 mg/d) groups. The experimental period was 16 wk, consisting of 2-wk pretreatment, 12-wk treatment, and 2-wk posttreatment periods. All cows were injected once daily starting at 53 to 180 d postpartum, housed in free stalls, and fed one of five total mixed rations according to milk production. Body weights were measured weekly, and body condition was scored biweekly. Milk yield was recorded daily, and weekly milk samples were analyzed for fat, protein, lactose, total solids, and SCC. Milk yield and milk protein were increased 18.8% (38.6 vs. 32.5 kg/d) and 3.3% (3.1 vs. 3.0%), respectively, whereas percentage of milk fat, lactose, SNF, SCC, and BW were unaffected by treatment. Overall average body condition scores were lower for the sometribove-treated group versus control (2.2 vs. 2.4). No apparent differences in the number of cows treated for mastitis, foot rot, displaced abomasum, or lameness were observed between treatment groups. Sometribove treatment significantly enhanced milk yield (6.1 kg/d) with no apparent negative effects on health in high producing cows milked three times per day.

Saccharomyces cerevisiae boulardii CNCM I-1079 (live yeast; ProTernative®, Lallemand Animal Nutrition) was evaluated for effects on health and performance in high-risk feeder heifers. A total of 1,274 beef heifers (average body weight = 547 ± 28.7 lb; 248 ± 13.0 kg) were procured from auction markets in the southern United States. Heifers were randomly assigned to 1 of 2 treatments: 1) Control (CON; no yeast products) or 2) ProTernative® (PRO) fed at 1 gram/hd/day to provide 20 x 109 CFU/hd/day for the first 45 days-on-feed (8 pens/treatment). After 45 days-on-feed, PRO was removed from the diet and both the PRO and CON treatment groups were fed the same basal diets throughout the rest of finishing. Feeding PRO during the first 45 days decreased bovine respiratory disease first treatment 28.4% compared to CON (P=0.01), and improved average daily gain (P=0.05; +4.5%), feed:gain (P=0.02; -5.0%), cost of gain (P=0.04; -4.7%), percentage USDA quality grade Choice (P<0.01; +6.8%), and reduced A+ liver abscesses (P<0.01; -45.9%). Carcass weight and percentage USDA Choice carcasses decreased (P<0.01) concomitant with increased (P<0.01) percentage USDA Select carcasses as the number of times treated for bovine respiratory disease increased. Addition of PRO to the ration during the first 45 days improved health, performance, and carcass outcomes through closeout in high-risk feeder heifers.