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Sericea lespedeza (SL; Lespedeza cuneata) is a legume rich in condensed tannins that can be grazed or fed to small ruminants for parasite control. Condensed tannins, a secondary plant compound in SL, may lead to unintended consequences such as changes in production. In our preliminary research, there was consistently a reduction in serum and liver concentrations of Mo. The objective of this study was to determine the effect of SL with or without Mo supplementation on changes in BW, hematology, and serum biochemistry in lambs. Thirty ram lambs weaned in May (84 ± 1.5 d of age; 27 ± 1.1 kg) were blocked by BW, breed type (full or three-fourths Katahdin), and EBV of parasite resistance and randomly assigned to be fed 900 g of alfalfa-based supplement (CON; n = 10) or SL-based supplement (n = 20) for 103 d. Supplements were formulated to be isonitrogenous and isocaloric and to meet trace mineral requirements. Within the SL diet, half of the lambs received 490 mg sodium molybdate weekly (SLMO). Body condition scores and BW were determined every 14 d and blood and feces collected to determine hematological and serum biochemical profiles and fecal egg counts (FEC). Data were analyzed using a mixed model with repeated measures and orthogonal contrasts. The white blood cell counts tended to be reduced in SL- and SLMO-fed lambs compared with CON-fed lambs (P < 0.06), which was associated with a reduction in neutrophils (P < 0.001). Red blood cell counts were also reduced in SL but not SLMO lambs compared with CON lambs (P < 0.04). There was a reduction in blood packed cell volume (P < 0.04) and serum concentrations of albumin (P < 0.001) and creatinine (P < 0.02) in both SL and SLMO lambs compared with CON lambs. Similarly, concentrations of blood urea nitrogen were reduced in both SL and SLMO lambs, but differences among dietary treatments disappeared after 42 d of feeding (treatment × day, P < 0.004). Serum concentrations of total proteins were reduced only in SLMO lambs compared with other lambs (P < 0.001). Body weight and FEC were similar among dietary treatments. Means of all measurements were within a normal range, even though there were subtle but significant differences between dietary groups. Feeding a diet high in condensed tannin-rich SL did not lead to serious effects on hematology or serum biochemistry in lambs.

The objective of these experiments was to determine the effect of daily or alternate day supplementation of dried distillers grains with solubles (DDGS) with or without monensin on performance of grazing calves. Treatments included (1) a negative control with no supplemental feed except free-choice mineral; (2) DDGS offered daily at 1.02 kg as-fed per calf, including a mineral premix; (3) daily DDGS and monensin (Rumensin, Elanco, Greenfield, IN) at 1.02 kg as-fed per calf, including a mineral premix supplying 160 mg of monensin/calf daily; (4) alternate day DDGS to supply 2.04 kg as-fed per calf, including the mineral premix offered on alternate days; and (5) alternate day DDGS and monensin to supply 2.04 kg as-fed per calf, including a mineral premix and 320 mg of monensin/calf on alternate days. Four experiments were conducted which included both steers (n = 70) and heifers (n = 230) grazing warm season grass based pastures (Exp. 1, 2, and 3) or nontoxic endophyte-infected tall fescue (Exp. 4). Supplementation increased ADG (P ≤ 0.04) by 0.16 to 0.26 kg/d in the 4 studies, with an average improvement (P

Silage intake by ruminants can be affected by both fertilization and forage type. The objective of this study was to evaluate digestion by sheep offered three different grasses fertilized with either urea (C) or dairy slurry (S). Plots of meadow fescue (MF), tall fescue (TF) or orchardgrass (OG) were planted on 25 July 2017, and first harvested on 29 June 2018. Plots were then fertilized with urea (52 kg N/ha) or slurry (71,150 L/ha). A second harvest was baled 6 August at approximately 57% moisture and wrapped in plastic. Eighteen lambs (59 ± 1.5 kg) were allocated randomly to one of the 6 treatment combinations to provide 3 lambs per treatment within each of 3 periods consisting of a 10-d adaptation and 7-d total fecal and urine collection. Data were analyzed as a 2 × 3 factorial arrangement using PROC MIXED of SAS. Dry matter (DM) and organic matter (OM) intakes (g/kg BW) were greater (P < 0.05) from MF fertilized with C than from the other forage-fertility combinations. Digestibility of DM and OM were greater (P < 0.05) from MF vs. OG, and OG vs. TF. Digestibility of OM also was greater (P < 0.05) from C vs. S. Digestible DM and OM intakes (g/kg BW) were greatest (P < 0.05) from MF fertilized with C. In addition, digestible DM intake (g/kg BW) was greater (P < 0.05) for MF fertilized with S compared to TF fertilized with C, and digestible OM intake was greater (P < 0.05) for MF fertilized with S compared to OG fertilized with S. Therefore, urea-fertilized meadow fescue may improve energy intake compared with that from orchardgrass or tall fescue, but fertilization of meadow fescue with slurry may reduce this advantage. The study was supported in part by USDA-ARS specific cooperative agreement 58-3655-4-052.

Poor silage fermentation can affect its acceptance by livestock. Alfalfa from 3 field blocks were baled in large round bales (moisture concentration = 591 ± 43.0 g/kg) and then wrapped with 7 layers of plastic either with (EOB) or without (CW) an enhanced oxygen barrier on the day of baling, or 1, 2 or 3 d after baling in order to examine those effects on subsequent intake and digestibility by gestating sheep. Alfalfa was chopped after approximately 5 mo. of fermentation, and then offered for individual ad libitum consumption by 16 gestating ewes [63.5 ± 1.71 kg avg. body weight (BW)] in a 3-period (63-day) digestion study. Silage moisture and nitrogen (N) decreased linearly (P < 0.05), acid-detergent fiber (ADF) increased linearly (P < 0.05), and neutral-detergent fiber (aNDF) increased at a decreasing rate (linear; quadratic P < 0.05) with wrapping delay within EOB but not CW (P ≥ 0.23). Lactic acid expressed as g/kg of total silage acids decreased linearly (P < 0.05) within CW and decreased at an increasing rate (linear; quadratic P < 0.05) within EOB with increasing wrapping delay, likely because of aerobic deterioration. Digestible organic matter intake (DOMI) decreased linearly (P = 0.03) within EOB and quadratically (P = 0.02) within CW (wrap type × wrapping time after baling interaction; P = 0.04), but other intake and digestibility measurements were not affected (P ≥ 0.15) by wrap type or its interaction with wrapping time after baling. Intake of DM and OM (DMI and OMI, g/kg BW) as well as digestible DMI (g/kg BW) responded linearly and quadratically (P ≤ 0.03) with wrapping delay after baling by initially increasing to 1 d after baling, then declining sharply thereafter. Digestibility of aNDF increased linearly (P = 0.04) with wrapping delay which was likely related to reduced DMI. These values align somewhat closely with those for forage quality and fermentation profiles. Therefore, managing alfalfa silage to ensure more desirable fermentation should also result in higher digestible OMI, which will improve the overall energy status of ruminants.

Crabgrass ( Digitaria ciliaris [Retz.] Koel.) is a high-quality warm-season annual that can be used as hay, but field curing time may be lengthy compared with other forages. A 1.6-ha field of common crabgrass was divided into 12 plots (8.25 m × 50 m) that were used in a randomized complete block design with a 2 × 2 factorial treatment arrangement to determine the effects of a non-viable Lactobacillus –lactic acid additive and moisture concentration at baling on heating characteristics and pre- and post-storage chemical composition. Half of the plots within each block were treated with 0.081 ml/mg dry matter (DM) of a solution containing 110 g lactic acid/kg and non-viable Lactobacillus acidophilus at the time of mowing (T) and half were not treated (U). Within T and U plots, half were baled in small square bales at 163 g moisture/kg DM (L) and half at 251 g moisture/kg DM (H) of moisture. Six bales per plot were selected at random, weighed, and stored in separate insulated 6-bale stacks. Core samples were taken from 3 bales initially and 3 bales post-storage. Initial bale moisture concentrations were greater (P vs. L. Post-storage concentrations of NDF and acid-detergent insoluble N (ADIN; g/kg DM and g/kg N), were greater (P vs. L. Dry matter intake in sheep was unaffected (P>0.05) by either treatment, but DM digestibility and digestible DM intake were both positively affected (P L. In situ DM disappearance was largely affected by spray treatment × moisture interactions (P

Fertilizing bermudagrass (Cynodon dactylon L. Pers.) with N can produce large quantities of forage and increase plant N concentrations. Bermudagrass growing on a caged-layer manure-amended site was fertilized with ammonium nitrate at 4 rates (0, 56, 112, and 168 kg N/ha) approximately 1 mo before first and third harvests on May 30 and August 18, 2000, to determine in situ disappearance kinetics of N and neutral detergent insoluble N (NDIN). Five crossbred ruminally cannulated steers (BW = 422 ± 21.0 kg) were used to evaluate in situ disappearance kinetics in a randomized complete block design with a 2 × 4 factorial arrangement. Immediately soluble N (fraction A) and rate of N disappearance increased linearly (P

‘Common’ and ‘Tifton 44’ bermudagrass [Cynodon dactylon (L.) Pers.] located near Fayetteville and Batesville, AR, respectively, were chosen to evaluate the effects of stockpiling initiation date (August or September), and N fertilization rate (0, 37, 74, or 111 kg N ha 21 )o n the nutritive value of fall-stockpiled bermudagrass. At the Fayetteville location, there were initiation 3 harvest date interactions for acid detergent fiber (ADF, P 5 0.003), hemicellulose (P 5 0.003), cellulose (P 5 0.0003), lignin (P 5 0.007), and crude protein (CP, P 5 0.008) in 2000, and strong interactions (P # 0.001) for all response variables in 2001. Generally, neutral detergent fiber (NDF), ADF, cellulose, and lignin increased over harvest dates for both initiation dates in 2000, although increases for lignin were only numerical (P . 0.05) for the September initiation date. Similar responses were observed for the August initiation date in 2001, but fiber components for the September 2001 initiation date declined over time because of contamination by other winter-annual species. For August initiation dates in 2000 and 2001, in vitro organic matter disappearance (IVOMD) declined linearly (P # 0.002) over harvest dates, reaching respective minima of 330 and 361 g kg 21 . At the Batesville site, an N fertilization effect (P # 0.017) was observed for NDF, ADF, and CP in both 2000 and 2001. A similar effect was observed for lignin (P 5 0.001) and IVOMD (P , 0.0001) in 2000, and for cellulose (P 5 0.0004) during 2001. Fertilization with N at the initiation of stockpiling generally reduced fiber components, and increased CP; however, IVOMD was increased for 2000 only. As observed for the Fayetteville site, most fiber components increased over harvest dates, while IVOMD declined concomitantly. Generally, the nutritive value of stockpiled bermudagrass declines between mid-October and mid-December, and spring-calving beef cows in the Upper South may need to be supplemented with energy to maintain body condition in the late fall or early winter.

Previous methodologies to measure losses of dry matter (DM) in wilting hays subjected to natural or simulated rainfall have relied generally on gravimetric techniques, resulting in variable and questionable estimates of DM loss. The objective of this study was to evaluate the use of fiber components and acid detergent insoluble ash (ADIA) as internal plant markers for accurately predicting losses of DM in bermudagrass [Cynodon dactylon (L.) Pers.] and orchardgrass (Dactylis glomerata L.) forages that were damaged by simulated rainfall. For both forages, concentrations of neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose (HEMI), cellulose (CELL), lignin, and ADIA generally increased with the amount of simulated rainfall in primarily linear patterns. Recoveries of all internal markers were high (≥952 g kg -1 ) and were not affected by simulated rainfall for either forage (P ≥ 0.06). Predicted losses of DM increased in primarily linear patterns with simulated rainfall for both forages when concentrations of NDF, ADF, HEMI, CELL, and ADIA were used as internal markers. Linear regressions of predicted losses of DM on values determined gravimetrically were good (r 2 ≥ 0.73; P ≤ 0.03) when concentrations of any fiber constituent or ADIA were used to calculate losses of DM; however. NDF was an especially effective internal marker (Y = 1.12X - 5; r 2 = 0.97; P < 0.01).

Common bermudagrass [Cynodon dactylon (L.) Pers.] was harvested from two producer sites (Latta and Stephens) with high soil-test P (286 and 153 ppm, respectively) to assess the effects of N fertilization on P uptake and potential removal in hay or silage. Ammonium nitrate was applied in split applications each year at rates totaling 0, 56, 112, 168, 224, 280, or 336 kg/ha of actual N. At the Stephens site in Yr 1, cumulative DM yield increased linearly (P 0.10) between concentration of P and N fertilization rate (overall mean = 0.40%), but concentrations of P declined in linear (P

Common bermudagrass [Cynodon dactylon (L.) Pers.] growing on a poultry layer manure-amended site (layer manure was last applied in 1999) was fertilized with ammonium nitrate at four rates (0, 56, 112, and 168 kg N ha−1) at approximately 1 month before first and third harvests on 30 May and 18 August 2000 to evaluate forage concentrations of S and Mo, and concentrations and ruminal disappearance of Fe, Zn, and Cu. Five crossbred ruminally cannulated steers (422±21.0 kg BW) were used to evaluate ruminal disappearance of Fe, Zn, and Cu from these forages in situ in a randomized complete block design with a 2×4 (harvest date×N fertilization rate) factorial arrangement of treatments. Forage S concentrations decreased linearly (P=0.02) with increasing N application on both harvest dates, but Fe, Zn, Cu, and Mo concentrations did not differ (P≥0.24) across N fertilization rates. The intercepts for the regressions of S, Zn, Cu, and Mo concentrations on N fertilization rate were higher (P

Minerals are essential nutrients for animals as primordial elements for structural tissues and metabolic reactions. Forages are considered an important source of minerals for ruminants, but forage mineral concentrations may vary across the growing season due to several factors such as forage species and fertilization levels. Common bermudagrass [Cynodon dactylon (L.) Pers.] growing on a poultry layer manure-amended site was fertilized with ammonium nitrate at four rates (0, 56, 112, and 168 kg N/ha) approximately 1 month before the first and third harvests (30 May and 18 August 2000, respectively) to evaluate those effects on forage concentration and ruminal disappearance of Ca, P, Mg, and K. Five crossbred ruminally cannulated steers (422 ± 21.0 kg BW) were used to evaluate these forages in situ in a randomized complete block design with a 2 x 4 (harvest date x N fertilizationrate) factorial arrangement of treatments. Forage P content decreased (P < 0.01) with increasing N fertilization on 18 August, while forage Mg increased (P < 0.01) and forage Ca content tended (P = 0.08) to increase with increasing N fertilization on both harvest dates. Approximately, 992 g/kg of the K disappeared immediately (fraction A) from the bags compared with approximately 821, 718, and 476 g/kg of Mg, P, and Ca, respectively. Fraction A, fraction B (the fraction disappearing at a measurable rate), and effective ruminal disappearance of Ca, P, Mg, and K were affected by linear or quadratic interactions between N fertilization and harvest date. Effective P disappearance increased linearly (P < 0.05) on 30 May and decreased quadratically (P < 0.01).

Nutrient composition and in situ dry matter (DM) and neutral detergent fiber (NDF) degradation of bermudagrass [Cynodon dactylon (L) Pers.] may vary with different management and environmental factors. This study evaluated nutritional value and in situ degradation characteristics of DM and NDF for bermudagrass, a perennial, warm-season grass. Bermudagrass growing on a poultry layer—litter—amended site was fertilized with ammonium nitrate at four rates (0, 56, 112, and 168 kg N ha−1) on 28 April and 19 July 2000, then harvested on 10 May and 18 August 2000. Five crossbred ruminally-cannulated steers (422±21.0 kg body weight (BW)) were used in a randomized complete block design with a 2×4 (harvest date×N fertilization rate) factorial arrangement to determine in situ DM and NDF degradation kinetics. Quadratic relationships were detected between N fertilization rates and N concentration in the plant when harvested on 30 May (y=0.0001x2+0.009x+27; P 0.05) across N fertilization rates. The undegraded DM fraction (fraction C) declined (P

Mixed breed steers (n = 96; 211 ± 1.48 kg) were used for a 35-d trial to determine the effects of amprolium and supplemental thiamin on thiamin status and growth performance of stressed cattle. Amprolium at 0 or 5 mg/kg initial BW and thiamin at 0 or 140 mg/kg DM were fed in a 2 × 2 factorial arrangement of treatments. Amprolium was top-dressed on the daily feed for the first 21 d of the study; each steer had 50-cm bunk space available. Steers were kept in 3.7 m × 30.5 m drylots (n = 16; 6 steers per pen and 4 pens per treatment) and were fed a corn, soybean meal, cottonseed hull-based total mixed ration. A pen was used as the experimental unit. Steers fed amprolium had increased ADG from d 0 to 7 (P 0.10) TMP and TPP concentrations on d 7 and 35. Thiamin supplementation had no effect on the number of coccidial oocysts in feces, but steers fed amprolium had reduced numbers of coccidial oocysts (P

A 64-d grazing study was conducted with a 2 × 2 factorial arrangement of treatments to evaluate the impact of implant treatment on growth performance, hair score, and serum prolactin levels of steers grazing tall fescue with high (HE) or low (LE) levels of infection with the endophytic fungus Neotyphodium coenophialum. Mixed-breed steers (n = 130; 246 ± 3.5 kg initial BW) were allocated randomly to one of three HE or one of four LE pastures beginning April 13. Within each replication, one-half of the steers were implanted (IMP) with trenbolone acetate (40 mg) and estradiol (8 mg), and one-half were not implanted (NI). No implant treatment × endophyte level interactions were detected (P>0.10). Steers grazing HE had lower (P 0.10) between IMP and NI steers on either d 36 or 64. When tabulated across forage and implant treatments, correlations were negative between overall BW gains and hair scores measured on d 64 (r = 0.28; P

Ruminal in situ disappearance kinetics of forages are commonly evaluated in confined animals, but there have been relatively few attempts to evaluate disappearance kinetics of forage dry matter (DM) in grazing animals. Our objectives were 1) to evaluate the effects of harvest technique and sampling date on the in situ DM disappearance kinetics and nutritive value of wheat ( Triticum aestivum L.) forage, and 2) to compare the in situ disappearance kinetics of DM for these forages when the experimental steers were housed in confinement with those obtained from steers grazing wheat pasture. Wheat forage was harvested on three dates (March 6, March 27, and April 11, 2000). Sampling techniques evaluated on each date included three clipping techniques (whole plant, random pluck, and top half) and two evaluations of masticates (oven dried at 50°C or lyophilized). There was an interaction of harvest technique and sampling date main effects for crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose, cellulose, lignin, and whole-plant ash. Disappearance kinetics of DM for these 15 forages were then evaluated by the in situ technique using five 393-±54-kg crossbred steers consuming an alfalfa-based ( Medicago sativa L.) diet in confinement, and subsequently, in five 448±49-kg crossbred steers grazing wheat pasture during March 2001. For fractions A, B, and C, potential extent, rate of disappearance (K d ), and effective ruminal degradability, linear regressions of values obtained for steers grazing wheat pasture on those obtained from confined cattle had significant slopes and exhibited high r 2 statistics (>0.821). For fractions A and B, and K d , the slope of these regression lines did not differ from unity, and the intercept did not differ from zero. For fraction C, potential extent of disappearance, and effective ruminal degradability, slopes were all equal to 1.19 and differed from unity. For effective degradability, deviation of the slope from unity can be explained, in part, on the basis of the passage rates used to calculate these values (0.035 and 0.062/h for confined and grazing steers, respectively). From a practical standpoint, the in situ disappearance kinetics of DM for these wheat forages did not appear to be altered substantially by evaluating them in grazing steers.

Background The potential for acid-detergent insoluble ash (ADIA), alkaline-peroxide lignin (APL), and acid-detergent lignin (ADL) to predict fecal output (FO) and dry matter digestibility (DMD) by cattle offered bermudagrass [Cynodon dactylon (L.) Pers.] hays of different qualities was evaluated. Eight ruminally cannulated cows (594 ± 35.5 kg) were allocated randomly to 4 hay diets: low (L), medium low (ML), medium high (MH), and high (H) crude protein (CP) concentration (79, 111, 131, and 164 g CP/kg on a DM basis, respectively). Diets were offered in 3 periods with 2 diet replicates per period and were rotated across cows between periods. Cows were individually fed 20 g DM/kg of body weight in equal feedings at 08:00 and 16:00 h for a 10-d adaptation followed by a 5-d total fecal collection. Actual DM intake (DMI), DMD, and FO were determined based on hay offered, ort, and feces excreted. These components were then analyzed for ADL, APL, and ADIA concentration to determine marker recovery and marker-based estimates of FO and DMD. Results Forage DMI was affected by diet (P = 0.02), and DMI from MH and H was greater (P