Bahiagrass Hay Research Articles

Methane emissions and 13C composition from beef steers consuming binary C3-C4 diets.

Improvements in forage nutritive value can reduce methane emission intensity in grazing ruminants. This study was designed to evaluate how the legume rhizoma peanut (Arachis glabrata; RP) inclusion into bahiagrass (Paspalum notatum) hay diets would affect intake and CH4 production in beef steers. We also assessed the potential to estimate the proportion of RP contribution to CH4 emissions using δ13C from enteric CH4. Twenty-five Angus-crossbred steers were randomly allocated to one of five treatments (five steers per treatment blocked by bodyweight): 1) 100% bahiagrass hay (0%RP); 2) 25% RP hay + 75% bahiagrass hay (25%RP); 3) 50% RP hay + 50% bahiagrass hay (50%RP); 4) 75% RP hay + 25% bahiagrass hay (75%RP); 5) 100% RP hay (100%RP). The study was laid out using a randomized complete block design, and the statistical model included fixed effect of treatment, and random effect of block. Methane emissions were collected using sulfur hexafluoride (SF6) technique, and apparent total tract digestibility was estimated utilizing indigestible neutral detergent fiber as an internal marker. A two-pool mixing model was used to predict diet source utilizing CH4 δ13C. Inclusion of RP did not affect intake or CH4 production (P > 0.05). Methane production per animal averaged 250 g CH4/d and 33 g CH4/kg dry matter intake, across treatments. The CH4 δ13C were -55.5, -60.3, -63.25, -63.35, and -68.7 for 0%RP, 25%RP, 50%RP, 75%RP, and 100%RP, respectively, falling within the reported ranges for C3 or C4 forage diets. Moreover, there was a quadratic effect (P = 0.04) on the CH4 δ13C, becoming more depleted (e.g., more negative) as the diet proportion of RP hay increased, appearing to plateau at 75%RP. Regression between predicted and observed proportions of RP in bahiagrass hay diets based on δ13C from CH4 indicate δ13C to be useful (Adj. R2 = 0.89) for predicting the contribution of RP in C3-C4 binary diets. Data from this study indicate that, while CH4 production may not always be reduced with legume inclusion into C4 hay diets, the δ13C technique is indeed useful for tracking the effect of dietary sources on CH4 emissions.

Stable isotopes of C and N differ in their ability to reconstruct diets of cattle fed C3–C4 forage diets

Stable isotopes are useful for estimating livestock diet selection. The objective was to compare δ13C and δ15N to estimate diet proportion of C3–C4 forages when steers (Bos spp.) were fed quantities of rhizoma peanut (Arachisglabrata; RP; C3) and bahiagrass (Paspalumnotatum; C4).Treatments were proportions of RP with bahiagrass hay: 100% bahiagrass (0%RP); 25% RP + 75% bahiagrass (25%RP); 50% RP + 50% bahiagrass (50%RP); 75% RP + 25% bahiagrass (75%RP); and 100% RP (100% RP). Feces, plasma, red blood cell (RBC), and hair were collected at 8-days intervals, for 32 days. Two-pool mixing model was utilized to back-calculate the proportion of RP based on the sample and forage δ13C or δ15N. Feces showed changes using δ13C by 8 days, and adj. R2 between predicted and observed RP proportion was 0.81 by 8 days. Plasma, hair, and RBC required beyond 32-days to reach equilibrium, therefore were not useful predictors of diet composition during the study. Diets were best represented using fecal δ13C at both 8-days and 32-days. By 32-days, fecal δ15N showed promise (R2 = 0.71) for predicting diet composition in C3–C4 diets. Further studies are warranted to further corroborate fecal δ15N as a predictor of diet composition in cattle.

Triterpenes from Olea europaea modulate in vitro ruminal fermentation.

Bioactive compounds present in Olea europaea have shown promising antimicrobial potential as an alternative to conventional coccidiostats. These effects are exerted by triterpenic acids (TT) present in the olive plant, namely, oleanolic acid (OA), ursolic acid (UA), and maslinic acid (MA). The objective of this study was to determine the effects of OA, UA, and MA on in vitro ruminal fermentation in comparison with monensin (MON). The study consisted of two experiments conducted as randomized complete block designs using bahiagrass hay or a high-concentrate mixed ration as basal substrates. In the first experiment (Exp. 1), a batch culture was performed with increasing doses of OA, UA, or MA. In Exp. 2, to increase the solubility of OA, two chemical forms were evaluated: a sodium salt (OA-NA) or a phyto-phospholipid complex (OA-PHYT) at 0, 4, 40, 100, and 200 mg/L of incubation inoculum. In both experiments, the dose 0 was used as control (CTL) and monensin (MON) as a positive control. Data were analyzed as a randomized complete block design with a factorial arrangement of treatments. For Exp. 2, orthogonal polynomial contrasts, adjusted for unequal spacing were used to determine the linear effects of increasing doses of OA-NA and OA-PHYT. In Exp. 1, OA reduced the concentration of CH4 in the high-concentrate substrate compared with CTL (P = 0.04). In Exp. 2 the total gas production was linearly decreased with increasing doses of OA-NA in both substrates (P ≤ 0.02). Furthermore, OA-NA and OA-PHYT decreased in vitro organic matter digestibility (P < 0.01) in the bahiagrass substrate to the same extent that MON did. However, the concentration of CH4/g of incubated DM was only reduced by the highest doses of OA-NA (P < 0.02). Lastly, no effects were observed for total VFA nor the VFA profile; however, OA-NA linearly decreased the A:P ratio in the bahiagrass substrate (P = 0.03). In conclusion, the acid form of OA as well as the sodium salt and phyto-phospholipid complex of OA were able to modify some fermentation parameters in this study; however, the magnitude of the responses was lower compared with monensin. Future studies should test OA in vivo to determine if the effects on ruminal fermentation observed here can translate into improve production efficiency while reducing carbon emissions.

Intake, ruminal fermentation parameters, and apparent total-tract digestibility by beef steers consuming Pensacola bahiagrass hay treated with calcium oxide.

To determine the effect of CaO-treated Pensacola bahiagrass (Paspalum notatum) hay on intake, ruminal fermentation parameters, and apparent total-tract digestibility of nutrients, nine ruminally cannulated Angus-crossbred steers were used in a triplicated 3×3 Latin square design. Steers had ad libitum access to either 1) untreated dry hay (DH; n = 8); 2) hay at 50% DM treated with 8.9% CaCO3 (dry matter [DM] basis; CC; n = 9); or 3) hay at 50% DM treated with 5% CaO (DM basis; CO; n = 8). Water was added to reach 50% DM in the CC and CO diets. Ruminal fluid and blood samples were collected every 3h for 24h. Ruminal fluid was analyzed for pH, volatile fatty acids (VFA), and ammonia-nitrogen (NH3-N). Blood was analyzed for plasma urea nitrogen (PUN). Hay and fecal samples were collected for 4 d, four times daily for hay and twice daily for feces, to determine apparent total-tract digestibility of nutrients. The hay provided to steers during the digestibility period was analyzed for in vitro organic matter digestibility (IVOMD) for 48h. Data were analyzed as repeated measures for blood and ruminal fermentation parameters. Total DM intake was not affected (P ≥ 0.674) by treatment. A treatment effect (P < 0.001) was observed for average ruminal pH, where steers consuming CO had the greatest pH (P < 0.001). Ruminal concentration of NH3-N tended (P = 0.059) to be reduced in steers consuming CO. There was a treatment × time interaction (P = 0.023) on concentrations of PUN, where at 3h DH and CO were lesser than CC (P ≤ 0.050) and at 21h DH was lesser than CC (P = 0.020). Total VFA, acetate, propionate, butyrate, branched-chain VFA, and valerate concentrations were affected by treatment (P ≤ 0.035), where a reduction (P ≤ 0.034) occurred in steers consuming CO. No treatment differences were observed for total-tract digestibility of DM (P = 0.186), organic matter (P = 0.169), or crude protein (P = 0.152); however, steers consuming DH had greater neutral detergent fiber (P = 0.038) than CC and tended to be greater than CO (P = 0.082). The CO hay had greater (P = 0.005) IVOMD compared with DH and tended (P = 0.100) to be greater than CC. Bahiagrass hay treated with CaO may reduce ruminal fermentation, as indicated by decreased total VFA concentration without altering DM intake. The addition of CaO did not improve the digestibility of bahiagrass hay in vivo; however, in vitro results are contradictory and warrant further elucidation.

Performance of growing beef cattle consuming bahiagrass hay treated with calcium oxide and molasses

Two experiments were conducted to evaluate the effects of Pensacola bahiagrass (Paspalum notatum) hay treated with calcium oxide (CaO) and molasses on performance of growing beef cattle supplemented or not with cottonseed meal. In Exp. 1, growing Bos indicus influenced heifers (n = 59; 250 ± 29 kg body weight [BW]) and steers (n = 37; 256 ± 45 kg BW) were used. In Exp. 2, heifers (n = 56; 249 ± 26 kg BW) and steers (n = 8; 249 ± 20 kg BW) from Exp. 1 were used. Both experiments were randomized complete block designs and consisted of 56-d periods in which cattle were weighed every 14 d. On day 0, cattle were weighed after a 16-h water and feed withdrawal, stratified by sex, breed, and BW, and blocked by initial BW. Cattle were allotted to 24 and 16 dormant bahiagrass pastures (1.34 ha each) in Exp. 1 and Exp. 2, respectively. Pastures were located in two different areas within 0.52 km of each other and were stratified by location and randomly assigned (n = 8 pastures/treatment) to treatment. In Exp. 1 treatments were: 1) untreated dry hay (DH); 2) hay treated with 10% molasses (dry matter [DM] basis) + water (to 65% DM; MOL); or 3) hay treated with 5% CaO (DM basis) + 10% molasses (DM basis) + water (to 65% DM; CAO). In Exp. 2 only treatments MOL and CAO were applied, and cottonseed meal was provided at 0.3% of cattle BW/d (as fed basis). In both experiments, data were analyzed using pasture as the experimental unit. The model included the fixed effects of treatment, sex, and their interaction (Exp. 1). Location and block were included as random effects. In both experiments, initial and final BW were not affected by treatment (P ≥ 0.362 and P ≥ 0.283, respectively) or sex (P ≥ 0.512 and P ≥ 0.495, respectively) and no treatment × sex interaction was observed in Exp. 1 (P > 0.05). Additionally, no effects of treatment (P ≥ 0.515), sex (P ≥ 0.285), or treatment × sex interaction (Exp. 1; P = 0.582) were observed on average daily gain (average of −0.03 kg in Exp. 1 and 0.537 kg in Exp. 2). Bahiagrass hay treated with molasses alone or in combination with CaO failed to improve performance of growing beef cattle. However, when protein supplementation via cottonseed meal was provided, cattle did not experience weight loss.

Effects of bismuth subsalicylate and calcium-ammonium nitrate on ruminal in vitro fermentation of bahiagrass hay with supplemental molasses

There is a need to increase efficiency of beef production. Decreasing losses of CH4 and improving byproduct utilization are popular strategies. Two feed additives were tested to find potential solutions. Three randomized complete block design experiments were performed using batch culture systems to evaluate the effects of bismuth subsalicylate (BSS) and calcium-ammonium nitrate (CAN) on in vitro ruminal fermentation of bahiagrass hay and supplemental molasses. The first experiment contained four treatments: (1) basal substrate; (2) basal substrate with 0.75% urea (DM basis); (3) basal substrate with 1.2% CAN and 0.38% urea (DM basis); and (4) basal substrate with 2.4% CAN (DM basis). Treatments 2, 3, and 4 were isonitrogenous. The second experiment had a 4 × 3 factorial arrangement of treatments with 4 concentrations of BSS (0.00, 0.33, 0.66, and 1.00%; DM basis) and 3 concentrations of CAN (0.0, 1.2, and 2.4%; DM basis). The third experiment had the following treatments: (1) basal substrate; (2) basal substrate with 0.05% BSS (DM basis); (3) basal substrate with 0.10% BSS (DM basis); and (4) basal substrate with 0.33% BSS (DM basis). For all experiments, basal substrate consisted of Pensacola bahiagrass hay (Paspalum notatum Flüggé; 80% substrate DM) and molasses (20% substrate DM). All data were analyzed using the MIXED procedure of SAS. In Exp. 1, in vitro organic matter (OM) digestibility (IVOMD) was linearly reduced (P < 0.001) with the inclusion of CAN, and CH4, in mmol/g OM fermented, was decreased linearly (P < 0.001). The volatile fatty acid (VFA) profile was not impacted by the inclusion of nonprotein nitrogen (NPN) or CAN (P > 0.05). In Exp. 2, except for CH4 production (P < 0.05), there were no BSS × CAN interactions. Linear reductions in total gas production (P < 0.001), IVOMD (P < 0.001), and total concentration of VFA (P = 0.007) were observed with the inclusion of BSS up to 1%. The inclusion of BSS decreased H2S production in a quadratic manner (P = 0.024). In Exp. 3, IVOMD was not impacted by the inclusion of BSS (P > 0.05); however, production of H2S was linearly decreased (P = 0.004) with the inclusion of BSS up to 0.33%. In conclusion, in vitro fermentation was negatively impacted by the inclusions of BSS, up to 1%, and CAN, up to 2.4%; however, BSS decreased production of H2S when included up to 0.33% without impeding fermentation, while CAN decreased CH4 production.

Effects of bismuth subsalicylate and encapsulated calcium-ammonium nitrate on enteric methane production, nutrient digestibility, and liver mineral concentration of beef cattle.

Two randomized block designs were performed to evaluate the effects of bismuth subsalicylate (BSS) and encapsulated calcium-ammonium nitrate (eCAN) on enteric methane production, nutrient digestibility, liver mineral concentration, and performance of beef cattle consuming bahiagrass hay (Paspalum notatum; ad libitum) and sugar cane molasses [1.07 kg/d; dry matter basis]. Experiment 1, used 25 crossbred steers [335 ± 46 kg of initial body weight (BW)] with a 2 × 2 + 1 factorial arrangement of treatments for two 20 d periods. Factors were nonprotein nitrogen (NPN) source (350 mg/kg BW of nitrate or 182 mg/kg BW of urea), BSS (0 or 58.4 mg/kg BW), and a negative control (NCTRL; bahiagrass hay and molasses only). Steers were re-randomized for a second period (n = 10/treatment total). Intake, apparent total tract digestibility and enteric methane were evaluated. Experiment 2 used 75 crossbred heifers in 25 pens (3 heifers/pen; 279 ± 57 kg of initial BW), consuming the same diet and treatments as experiment 1, to determine liver mineral concentration and growth performance over 56 d. Orthogonal contrasts were used to evaluate the effects of NPN (NCTRL vs. others), source of NPN (NS; urea vs. eCAN), BSS, and NS × BSS. For experiment 1, no interactions were observed for any variables, nor were there any effects of NPN on total tract digestibility of nutrients, except for crude protein. Digestibility of all nutrients was reduced (P ≤ 0.021) for steers consuming eCAN compared with urea. There was no effect (P > 0.155) of BSS on digestibility of nutrients; however, BSS reduced (P = 0.003) apparent S retention. Enteric CH4 emission (g/kg BW0.75) was decreased (P = 0.051) by 11% with the addition of eCAN compared with urea. For experiment 2, no NS × BSS interactions (P ≥ 0.251) were observed to affect liver mineral concentration; however, the addition of BSS decreased liver concentration of Cu (P = 0.002) while increasing Fe concentration (P = 0.016). There was an NS × BSS interaction (P = 0.048) where heifers consuming eCAN and BSS had lesser final BW compared with heifers consuming urea and BSS. While eCAN may be a viable resource for mitigating enteric CH4 production of forage-fed cattle, the negative effects on digestibility should be considered. Furthermore, BSS, at the amount provided, appears to have no negative effects on digestibility of nutrients in forage-fed cattle; however, there may be deleterious impacts on performance depending upon what nitrogen source is supplied.

Effects of bismuth subsalicylate and encapsulated calcium ammonium nitrate on ruminal fermentation of beef cattle.

A replicated 5 × 5 Latin square design with a 2 × 2 + 1 factorial arrangement of treatments was used to determine the effects of bismuth subsalicylate (BSS) and encapsulated calcium ammonium nitrate (eCAN) on ruminal fermentation of beef cattle consuming bahiagrass hay (Paspalum notatum) and sugarcane molasses. Ten ruminally cannulated steers (n = 8; 461 ± 148 kg of body weight [BW]; average BW ± SD) and heifers (n = 2; 337 ± 74 kg of BW) were randomly assigned to one of five treatments as follows: 1) 2.7 g/kg of BW of molasses (NCTRL), 2) NCTRL + 182 mg/kg of BW of urea (U), 3) U + 58.4 mg/kg of BW of BSS (UB), 4) NCTRL + 538 mg/kg of BW of eCAN (NIT), and 5) NIT + 58.4 mg/kg of BW of BSS (NITB). With the exception of NCTRL, all treatments were isonitrogenous. Beginning on day 14 of each period, ruminal fluid was collected and rectal temperature was recorded 4× per day for 3 d to determine ruminal changes every 2 h from 0 to 22 h post-feeding. Ruminal gas cap samples were collected at 0, 3, 6, 9, and 12 h on day 0 of each period followed by 0 h on days 1, 2, 3, and 14. Microbial N flow was determined using Cr-Ethylenediaminetetraacetic acid, YbCl3, and indigestible neutral detergent fiber for liquid, small particle, and large particle phases, respectively. Data were analyzed using the MIXED procedure of SAS. Orthogonal contrasts were used to evaluate the effects of nonprotein nitrogen (NPN) inclusion, NPN source, BSS, and NPN source × BSS. There was no treatment effect (P > 0.05) on concentrations of H2S on day 0, 1, 2, or 14; however, on day 3, concentrations of H2S were reduced (P = 0.018) when NPN was provided. No effect of treatment (P = 0.864) occurred for ruminal pH. There was an effect of NPN source on total concentrations of VFA (P = 0.011), where a 6% reduction occurred when eCAN was provided. There were effects of NPN (P = 0.001) and NPN source (P = 0.009) on the concentration of NH3-N, where cattle consuming NPN had a greater concentration than those not consuming NPN, and eCAN reduced the concentration compared with urea. Total concentrations of VFA and NH3-N were not affected (P > 0.05) by BSS. There was an effect of BSS (P = 0.009) on rectal temperature, where cattle not consuming BSS had greater temperatures than those receiving BSS. No differences for NPN, NPN source, nor BSS (P > 0.05) were observed for microbial N flow. In conclusion, eCAN does not appear to deliver equivalent ruminal fermentation parameters compared with urea, and BSS has limited effects on fermentation.

152 Effects of mineral supplementation on performance and serum mineral status in beef steers grazing annual ryegrass

Abstract Thirty six crossbred (predominantly English with some Bos indicus influence) beef steers (initial BW 264.8 + 35.8 kg) were blocked by BW and used in a completely random design to examine the effects of mineral supplementation on performance and serum mineral status in beef cattle grazing annual ryegrass pastures for 84 d. All cattle were withheld from mineral for approximately 60 d prior to the initiation of the study and were allowed to graze dormant bahiagrass pastures (Paspalum notatum), and also had access to bahiagrass hay. On d -1, cattle were weighed and stratified by BW into Light (n = 6 pastures) and Heavy (n = 4 pastures) blocks and returned to their dormant warm season pasture. On d 0, cattle were weighed, a 10 mL blood sample was collected for serum mineral status and cattle were moved to their respective 1.2 ha annual ryegrass treatment pastures. Treatments were randomly assigned to pasture and consisted of CON (no complete mineral supplementation), or MIN (free choice access to a complete beef mineral.) Cattle grazed annual ryegrass for 84 d, after which a final BW was collected as well as a second 10 mL blood sample. Data were analyzed as a mixed model with weight block a random effect and treatment a fixed effect and pasture was the experimental unit. Supplementing MIN tended (P = 0.06) to increase total weight gain at d 84 and increased (P = 0.01) ADG (1.61 vs. 1.67 kg/d for CON and MIN, respectively). Additionally, feeding MIN resulted in increased serum Co, Zn, and Se (P = 0.01) but resulted in no differences in serum Fe and Cu (P &amp;gt; 0.10). Feeding MIN resulted in greater performance and increased some serum mineral levels, however the lack of response in serum Cu to MIN bears further examination.

94 Performance of growing beef cattle consuming bahiagrass hay treated with calcium oxide and molasses and supplemented with cottonseed meal

Abstract An experiment was conducted to evaluate the effects of bahiagrass (Paspalum notatum) hay treated with calcium oxide (CaO) and molasses, offered ad libitum, on performance of growing beef cattle supplemented with cottonseed meal. Sixty-four growing Bos taurus and Bos indicus influenced heifers (249 ± 26 kg of BW) and steers (249 ± 20 kg of BW) were used in a randomized complete block design. The experiment consisted of a 56 d period in which animals were weighed every 14 d. On d 0, animals were weighed after 16-h water and feed withdrawal, stratified by sex, breed, and BW, and blocked by initial BW. Cattle were then allotted to 16 dormant bahiagrass pastures (1.34 ha each; 4 animals/pasture), which were located in 2 different areas within 0.52 km of each other. Pastures were stratified by location and randomly assigned (n = 8 pastures/treatment) to 1 of 2 treatments: 1) hay treated with 10% molasses (DM basis) + water (to 35% DM; MOL) or 2) hay treated with 5% CaO (DM basis) + 10% molasses (DM basis) + water (to 35% DM; CAO). Cottonseed meal was provided at a rate of 0.3% of cattle BW/d (as fed basis). Data were analyzed using the MIXED procedure of SAS and pasture was the experimental unit. The model included the fixed effects of treatment and sex. Location and block were included as random effects. Initial and final BW were not affected by treatment (P = 0.573, P = 0.453; initial and final BW, respectively) or sex (P = 0.512, P = 0.670; initial and final BW, respectively). Additionally, no effects of treatment (P = 0.767) or sex (P = 0.285) were observed on ADG (average of 0.537 kg). In conclusion, bahiagrass hay treated with molasses alone or in combination with CaO failed to improve performance of growing beef cattle

21 Performance of growing beef cattle consuming bahiagrass hay treated with calcium oxide and molasses and supplemented with cottonseed meal

Abstract An experiment was conducted to evaluate the effects of bahiagrass (Paspalum notatum) hay treated with calcium oxide (CaO) and molasses, offered ad libitum, on performance of growing beef cattle supplemented with cottonseed meal. Sixty-four growing Bos taurus and Bos indicus influenced heifers (249 ± 26 kg of BW) and steers (249 ± 20 kg of BW) were used in a randomized complete block design. The experiment consisted of a 56 d period in which animals were weighed every 14 d. On d 0, animals were weighed after 16-h water and feed withdrawal, stratified by sex, breed, and BW, and blocked by initial BW. Cattle were then allotted to 16 dormant bahiagrass pastures (1.34 ha each; 4 animals/pasture), which were located in 2 different areas within 0.52 km of each other. Pastures were stratified by location and randomly assigned (n = 8 pastures/treatment) to 1 of 2 treatments: 1) hay treated with 10% molasses (DM basis) + water (to 35% DM; MOL) or 2) hay treated with 5% CaO (DM basis) + 10% molasses (DM basis) + water (to 35% DM; CAO). Cottonseed meal was provided at a rate of 0.3% of cattle BW/d (as fed basis). Data were analyzed using the MIXED procedure of SAS and pasture was the experimental unit. The model included the fixed effects of treatment and sex. Location and block were included as random effects. Initial and final BW were not affected by treatment (P = 0.573, P = 0.453; initial and final BW, respectively) or sex (P = 0.512, P = 0.670; initial and final BW, respectively). Additionally, no effects of treatment (P = 0.767) or sex (P = 0.285) were observed on ADG (average of 0.537 kg). In conclusion, bahiagrass hay treated with molasses alone or in combination with CaO failed to improve performance of growing beef cattle

Evaluation of Brassica carinata meal on ruminant metabolism and apparent total tract digestibility of nutrients in beef steers1,2.

Brassica carinata is a new oilseed crop with the potential of producing high-quality jet biofuel. A high-protein meal (~40% crude protein) is obtained as a byproduct of hexane-solvent oil extraction; however, limited research is available on the use of this meal as a protein supplement for beef cattle. A duplicated 4 × 4 Latin square design was used to determine the effects of supplementation with B. carinata meal on ruminal fermentation, digestibility, and blood metabolites in beef cattle consuming bahiagrass hay (Paspalum notatum Flüggé), compared with frequently used protein supplements. Eight Angus crossbred steers (473 ± 119 kg initial BW) were randomly allocated to 8 pens, over 4 periods of 28-d each. Within period, steers were assigned to 1 of 4 treatments: 1) 1.62 kg/d cottonseed meal (CSM); 2) 2.15 kg/d dry distillers grains plus solubles (DDGS); 3) 1.39 kg/d B. carinata meal pellets (BCM); or 4) 1.17 kg/d soybean meal (SBM), supplemented daily, on an isonitrogenous basis. Steers had ad libitum access to bahiagrass hay and water. Intake was measured using the GrowSafe system. Following a 14-d adaptation, feed and fecal samples were collected to determine apparent total tract nutrient digestibility using indigestible NDF as an internal marker. Blood and ruminal fluid samples were collected before providing the protein supplements and then every 3 h, during a 24-h period, to analyze urea nitrogen (PUN) and glucose in plasma, as well as ruminal pH, ammonia nitrogen (NH3-N), and VFA concentrations. Data were analyzed using PROC MIXED of SAS with repeated measures. Model included the fixed effects of treatment, time, treatment × time, square, and period, and the random effects of steer(square) and steer(treatment). No effect of treatment (P > 0.05) was observed for pH, NH3-N, or glucose concentration. An effect of treatment (P < 0.01) was observed for PUN, with steers receiving SBM having greater concentrations. A treatment × time interaction was observed (P < 0.05) for total VFA concentration, acetate to propionate ratio, and molar proportions of acetate, propionate, butyrate, and valerate. Steers consuming SBM had greater molar proportions of branched-chain VFA (P < 0.01) compared with CSM and DDGS. There was no effect of treatment (P > 0.05) on intake or apparent total tract digestibility of nutrients. Brassica carinata performed similarly to commonly used protein supplements indicating its viability as a protein supplement for beef cattle.

PSXII-11 Apparent total-tract digestibility of nutrients in beef steers consuming bahiagrass hay treated with calcium oxide.

PSXII-11 Apparent total-tract digestibility of nutrients in beef steers consuming bahiagrass hay treated with calcium oxide.

PSV-5 Effects of oleanolic acid on in vitro fermentation of bahiagrass hay and a high-grain substrate.

PSV-5 Effects of oleanolic acid on in vitro fermentation of bahiagrass hay and a high-grain substrate.

Supplementation of encapsulated cinnamaldehyde and garlic oil on pre- and postweaning growth performance of beef cattle fed warm-season forages

ABSTRACT Two experiments evaluated the effects of cinnamaldehyde and garlic oil on performance of grazing (Exp. 1) and drylot beef cattle (Exp. 2). Treatments in both experiments consisted of daily supplement fortification with (CNG) or without (CON) cinnamaldehyde and garlic oil (300 mg/d). In Exp. 1, 24 cow-calf pairs were allocated into limpograss (Hemarthria altissima; n = 4) or bahiagrass (Paspalum notatum; n = 4) pastures, which were randomly assigned to treatments (4 pastures per treatment) until weaning. Thereafter, 24 weaned heifers were allocated into bahiagrass pastures (4 pastures per treatment) for 72 d. In Exp. 2, 20 Brangus steers were fed bahiagrass hay ad libitum and concentrate DM supplementation at 1% of BW for 30 d. Effects of forage type, treatment, and interactions were not detected for growth, fecal egg counts, and plasma glucose and urea nitrogen of heifers and cows (P ≥ 0.11). The fly counts of CNG heifers on limpograss was less at weaning than for CON heifers (P = 0.03) but did not differ between CNG and CON heifers grazing bahiagrass (P = 0.66). Effects of treatment and treatment × day were not detected for postweaning growth, fecal egg counts, and plasma haptoglobin (P ≥ 0.43). In Exp. 2, effects of treatment and treatment × day were not detected for growth and total fly counts (P ≥ 0.34). Hence, daily supplementation of cinnamaldehyde and garlic oil did not affect growth and fecal egg counts of grazing or drylot cattle. Cinnamaldehyde and garlic oil reduced fly counts of heifers grazing limpograss but not heifers grazing bahiagrass.

113 Effects of Bismuth Subsalicylate and Calcium-Ammonium Nitrate on Liver Mineral Concentration and Performance of Growing Beef Heifers.

To evaluate the effects of bismuth subsalicylate (BSS) and encapsulated calcium-ammonium nitrate (eCAN) on performance and liver mineral concentration of growing cattle, 75 Bos taurus × Bos indicus heifers (279 ± 57 kg of initial BW; 15.6 ± 4.1 mo of age) were used in an incomplete randomized block design with a 2 × 2 + 1 arrangement of treatments. The experiment consisted of a 28-d adaptation period followed by a 56-d data collection period in which heifers were weighed every 14 d. Heifers were stratified, blocked by weight, and allotted to 25 dormant bahiagrass (Paspalum notatum) pastures where they received 1.07 kg/heifer/d of molasses and ad libitum access to bahiagrass hay. Pastures were randomly assigned to 1 of 5 treatments: NCTRL (no added NPN or BSS), U (urea supplemented at 182 mg/kg of BW), NIT (eCAN supplemented at 350 mg/kg of BW), UB (urea supplemented at 182 mg/kg of BW and BSS supplemented at 58.4 mg/kg of BW) and NITB (eCAN supplemented at 350 mg/kg of BW and BSS supplemented at 58.4 mg/kg of BW). Data were analyzed using the MIXED procedure of SAS with pasture as the experimental unit. Contrasts were used to determine: effect of NCTRL vs. all other treatments (N); source of NPN (NS); effect of BSS (B); and the interaction between NPN source and BSS (B×NS). Final BW was not affected by N (P = 0.470), NS (P = 0.384), or B (P = 0.600); however, there was a B×NS interaction (P = 0.048) where NITB heifers had lesser BW compared with UB heifers. There was no effect of N, NS, B, or B×NS for ADG measured within any time points (P > 0.05). For carcass ultrasound measurements, there was no effect (P > 0.05) of N, NS, or B on LM area; however, a B×NS interaction (P = 0.001) was observed for 12th-rib fat thickness where NITB heifers had less back-fat compared with UB heifers on d 56. Concentration of minerals in the liver was not affected by NS (P > 0.05). No B×NS interactions (P = 0.05) were observed affecting liver mineral concentration; however, the addition of BSS decreased liver concentration of Cu (P = 0.002). In conclusion, the addition of eCAN did not affect performance of growing heifers unless it was provided in combination with BSS, which may decrease growth performance. Furthermore, BSS may negatively affect trace mineral concentrations in the liver.

11 Upcycling Bahiagrass Hay Using Cull Potatoes As an Alternative Feed Resource.

11 Upcycling Bahiagrass Hay Using Cull Potatoes As an Alternative Feed Resource.

553 Effects of pentacyclic triterpenes on in vitro fermentation of bahiagrass hay and a high-grain substrate

Triterpenes are the most representative group of phytochemicals, comprising more than 20,000 recognized molecules. The diversity of triterpenes is highly associated with their broad range of pharmacological effects. Previous studies have demonstrated their anti-microbial potential. Our objective was to determine potential effects of pentacyclic triterpenes (TT) on in vitro batch culture fermentation of bahiagrass hay and a high-grain substrate. A randomized complete block design was used to determine the effects of increasing concentrations of the following TT types: oleanolic acid (OA), ursolic acid (UA) and malsinic acid (MAL) on in vitro fermentation of bahiagrass hay (BGH) or a high-grain substrate (HG) comprised of 43% soybean hulls pellets, 42% corn gluten feed pellets, and 15% peanut hulls (DM basis). Treatments were arranged as a 4 × 3 factorial with 4 doses (0, 4, 25 and 100 mg/L of incubation volume) for each of the 3 TT types. Four ruminally cannulated crossbred steers (362 ± 30 kg BW) were used as ruminal fluid donors. Two steers were fed HG ad libitum, while the other two steers were fed BGH ad libitum for at least 14 d prior to the first incubation day. Each replicate d, 125-mL serum bottles containing 50 mL of a 4:1 buffer:ruminal fluid inoculum and 0.63 g of BGH substrate (DM basis) were incubated for 48 h, and a 2:1 buffer:ruminal fluid inoculum and 0.63 g of HG substrate (DM basis) were incubated for 24 h. Three d (block) of incubation were performed. In vitro OM digestibility (IVOMD) was determined in a separate set of tubes. Data were analyzed using PROC MIXED of SAS with the fixed effect of treatment, and random effect of incubation day. No effect was observed (P>0.05) on total gas production, IVOMD, NH3-N concentration and H2S production. There was no effect (P>0.05) of any TT types or doses on concentrations or molar proportions of VFA. No effect (P>0.05) of TT type or dose were observed on acetate:propionate ratio (A:P). In conclusion, the acid form of the pentacyclic triterpenes did not affect ruminal fermentation of either substrate. Future studies should focus on increasing the solubility of these pentacyclic triterpenes by using a sodium salt.

539 Evaluation ofBrassica carinatameal on ruminal metabolism and nutrient digestibility of beef cattle

Brassica carinatais a new oilseed crop in Florida with the potential of producing high-quality biodiesel for use as jet biofuel. A high-protein meal (∼40% CP) is obtained as a byproduct of oil extraction; however, this meal has not been tested as a potential protein supplement for cattle. A duplicated 4 × 4 Latin square design was used to determine the effects of supplementation withB. carinatameal on ruminal fermentation, digestibility, and blood profile in beef cattle consuming bahiagrass hay (Paspalum notatum), compared with frequently used protein supplements. Eight Angus crossbred steers (473 ± 119 kg initial BW) were randomly allocated to 8 pens, over 4 periods of 28 d each. Within period, steers were assigned to one of four treatments: 1.62 kg/d cottonseed meal (CSM), 2.15 kg/d dry distillers grains with solubles (DDGS), 1.39 kg/dB. carinatameal pellets (BCM), or 1.17 kg/d soybean meal (SBM), supplemented daily, on an isonitrogenous basis. Steers had ad libitum access to bahiagrass hay and water. Intake was measured using the GrowSafe system. Following a 14 d adaptation, feed and fecal samples were collected twice daily for 4 d to determine apparent total tract nutrient digestibility using iNDF as an internal marker. Blood and ruminal fluid samples were collected every 3 h, during a 24 h period, to analyze blood urea nitrogen (BUN) and glucose in plasma, as well as pH, NH3-N, and VFA concentrations in ruminal fluid. Data were analyzed using PROC MIXED of SAS with repeated measures. Model included the fixed effects of treatment, time, treatment × time, square, and period, and the random effects of steer (square) and steer (treatment). No effect of treatment (P>0.05) was observed for pH, NH3-N, or glucose concentration. An effect of treatment (P<0.01) was observed for BUN, with steers receiving SBM having greater concentrations. There was no effect of treatment (P>0.05) on total VFA concentrations. Steers consuming CSM had greatest acetate molar proportion, and greater acetate to propionate ratio when compared with DDGS and BCM. Steers consuming DDGS had greatest molar proportions of butyrate and greater molar proportions of propionate compared with SBM and CSM. There was no effect of treatment (P>0.05) on DMI or apparent total tract digestibility of DM, OM, CP, NDF, or ADF.Brassica carinataperformed similarly to commonly used protein supplements, excluding VFA profile, indicating its viability as a protein supplement for beef cattle.

563 Effects of bismuth subsalicylate and calcium-ammonium nitrate on ruminal fermentation of beef cattle

A duplicated 5×5 Latin square design was used to determine the effects of bismuth subsalicylate (BSS) and encapsulated calcium-ammonium nitrate (eCAN) on ruminal fermentation of beef cattle consuming bahiagrass hay (Paspalum notatum) and cane molasses. Ten ruminally cannulated beef cattle were randomly assigned to 1 of 5 treatments as follows: 3.3 g/kg of BW of molasses (CTRL); CTRL + 182 mg/kg of BW of urea (N0B0); CTRL + 538 mg/kg of BW of eCAN (N1B0); N0B0 + 58.4 mg/kg of BW of BSS (N0B1); and N1B0 + 58.4 mg/kg of BW of BSS (N1B1). With exception of CTRL, all treatments were isonitrogenous. Ruminal fluid and rectal temperature was collected 4× per d for 3 d to determine ruminal changes every 2 h from 0 to 22 h post feeding. Ruminal gas cap samples were collected at 0, 3, 6, 9, and 12 h on d 0 of each period followed by 0 h on d 1, 2, 3, and 14. Repeated measures data were analyzed using the MIXED procedure of SAS with the fixed effects of treatment, time, treatment × time, square, period, and animal within square, and the random effect of animal within treatment. For non-repeated data, the model included the fixed effects of treatment, square, period, and animal within square. Orthogonal contrasts were used to evaluate the effects of NPN, eCAN, BSS, and eCAN × BSS. There was no treatment effect (P>0.05) on concentrations of H2S on d 0, 1, 2, or 14; however, on d 3, concentrations of H2S were reduced (P= 0.018) when NPN was provided. No effect of treatment (P= 0.864) occurred for ruminal pH. There was an effect of eCAN on total concentrations of VFA (P= 0.011), where a 6% reduction occurred when eCAN was provided. There were effects of NPN (P= 0.001) and eCAN (P= 0.009) on concentrations of NH3-N, where cattle consuming NPN had lesser concentrations than those consuming eCAN compared to urea. Total concentrations of VFA and NH3-N were not affected (P>0.05) by BSS. There was an effect of BSS (P= 0.009) on rectal temperature, where cattle not consuming BSS had greater temperatures than those receiving BSS. In conclusion, eCAN does not appear to deliver equivalent ruminal fermentation parameters compared to urea, as indicated by reductions in total concentrations of VFA and NH3-N.