In Vitro True Digestibility Research Articles

Microencapsulation of lemongrass and mangosteen peel as phytogenic compounds to gas kinetics, fermentation, degradability, methane production, and microbial population using in vitro gas technique.

The purpose of the current study was to evaluate the impact of various doses of microencapsulated lemongrass and mangosteen peel (MELM) on gas dynamics, rumen fermentation, degradability, methane production, and microbial population in in vitro gas experiments. With five levels of microencapsulated-phytonutrient supplementation at 0, 1, 2, 3, and 4% of substrate, 0.5 g of roughage, and a concentrate ratio of 60:40, the trial was set up as a completely randomized design. Under investigation, the amount of final asymptotic gas volume was corresponding responded to completely digested substrate (b) increased cubically as a result of the addition of MELM (P < 0.01) and a cubic rise in cumulative gas output. The amount of MELM form did not change the pH and NH3-N concentration of the rumen after 12 and 24 h of incubation. However, methane production during 24 h of incubation, the levels were cubically decreased with further doses of MELM (P < 0.01) at 12 h of incubation. Increasing the dosage of MELM supplementation at 2% DM resulted in a significant increase in the digestibility of in vitro neutral detergent fiber (IVNDF) and in vitro true digestibility (IVTD) at various incubation times (P < 0.05), but decreased above 3% DM supplementations. Moreover, the concentration of propionic acid (C3) exhibited the variations across the different levels of MELM (P < 0.05), with the maximum concentration obtained at 2% DM. The populations of Fibrobacter succinogenes, Ruminococcus albus, Ruminococcus flavefaciens, and Megasphaera elsdenii revealed a significant increase (P < 0.05), while the quantity of Methanobacteriales decreased linearly with increasing doses of MELM. In conclusion, the inclusion of MELM at a concentration of 2% DM in the substrate which could enhance cumulative gas production, NDF and true digestibility, C3 production, and microbial population, while reducing methane concentration and Methanobacterial abundance.

Forage yield and nutritive value of summer legumes as affected by row spacing and harvest timing

Winter wheat (Triticum aestivum L.) is an essential, high-quality forage used for grazing stocker cattle from fall to spring in the US Southern Great Plains (SGP). However, the lack of nutritious forages during summers limits grazing by stocker cattle. To fill this quality gap, a short season species capable of producing significant yield and quality of forage is necessary. A two-year experiment was conducted to evaluate the performance of three legumes: tepary bean (Phaseolus acutifolius A. Gray), mothbean [Vigna aconitifolia (Jacq.) Marechal], and soybean [Glycine max (L.) Merr.] as a control, at different harvest dates, in response to different row spacing (38 ​cm and 76 ​cm) and moisture levels (rainfed and irrigated). Results showed forage yield by all legumes planted at 38 ​cm spacing (4.5 and 3.9 ​Mg ​ha−1) was higher than at 76 ​cm spacing (3.4 and 2.4 ​Mg ​ha−1) in 2018 and 2019. Soybean was the most productive while mothbean had the highest relative feed value (RFV) in both 2018 and 2019 (160 and 118, respectively). Although soybean produced more forage, mothbean and tepary bean provided high quality forage in terms of neutral detergent fiber (NDF), acid detergent fiber (ADF), and in-vitro true digestibility (IVTD). The results indicate that no single legume species stands out as the unequivocal leader in delivering both high-quality and abundant forage. Consequently, the choice of which species to utilize should be tailored to the specific forage requirements and management goals. Future research should explore mothbean genotypes to identify cultivars with greater yield potential and develop agronomic practices that effectively utilize those cultivars.

Estimation of In Vitro True Digestibility and Fiber Degradation from Feedstuff Fiber Composition When Incubated in Equine Fecal Inoculum

Neutral detergent fiber (NDF) and acid detergent fiber (ADF) composition have been shown to predict in vitro true digestibility (IVTD), in vitro NDF digestibility (IVNDFD), and in vitro ADF digestibility (IVADFD) in ruminants. This study’s objective was to estimate in vitro digestibility measures within the DaisyII incubator using equine fecal inoculum from feedstuff NDF and ADF composition. Analyzed feedstuffs included alfalfa hay (Medicago sativa), Coastal Bermudagrass hay, soybean meal, rice bran, hempseed meal, and Bluebonnet® Equilene® Pellets. Data were analyzed using Akaike’s information criterion (AIC) within the R Statistical Program©. The highest ranked model for IVTD was the interaction of NDF and ADF: 10003.32 – 0.2904 × NDF − 0.4220 × ADF − 0.0010 × NDF × ADF (Adjusted R2 = 0.959 and AICc = 474.97). Sample IVNDFD was moderately predicted by ADF: 855.15 – 1.5183 × ADF (Adjusted R2 = 0.749 and AICc = 560.82). Feedstuff ADF produced the highest ranked model for IVNDFD: 881.91 – 1.5952 × ADF (Adj. R2 = 0.835 and AICc = 541.33). These results indicate the effectiveness of using feedstuff NDF and ADF composition to predict IVTD, IVNDFD, and IVADFD within equine fecal inoculum. The findings of this study provide better understanding of feedstuff digestibility using equine fecal inoculum, but more research is warranted for validation of the models and the potential impact in vivo.

PSX-12 Effects of Cottonseed Meal Supplementation on Calf Performance and Forage Utilization Grazing Late Season Summer Forage

Abstract Nutritive quality of perennial warm-season grasses during summer may limit the DMI of growing calves due to low protein and increased NDF content. Cottonseed meal (CSM) supplementation may improve forage utilization by increasing rumen degradable protein, but research in calves is limited. It was hypothesized that supplementation of CSM to heifers grazing mature forage would have improved performance due to greater forage DMI and fiber digestibility. Objectives were to compare the effects of CSM supplementation on calf gain performance, estimated forage intake, and in vitro true digestibility (IVTD) and neutral detergent digestibility (IVNDFD) of low-quality, warm-season forage. Angus heifers (n = 18) weighing 232.7 ± 12.6 kg were blocked by BW (light, medium, and heavy) and allocated to 6 paddocks (1.64 ha) of W.W. B-Dahl Bluestem (Bothriochloa bladhii) for 67 d. Heifers were supplemented daily with a mineral mix and either no cottonseed meal (CON) or 454 g/animal of CSM (CSM1) in a RCBD with a 2×3 factorial arrangement of treatments and BW blocks, respectively. Initial and final shrunk BW was measured to calculate total gain, ADG, and percent of BW gained. Forage samples were collected weekly and composited into 3 periods for chemical analysis and in vitro incubations. Forage DMI was estimated using a double sampling technique for each paddock within period. Forage IVTD and IVNDFD were analyzed using batch fermentation with and without CSM in a CRD (2 treatments by 3 periods). Mean forage CP during periods 1 and 2 were 5.75% and increased to 10.3% in period 3 (P &amp;lt; 0.01). Forage NDF content increased over time (64.1 vs. 69.3%; P &amp;lt; 0.01) and estimated forage DMI of heifers tended (P = 0.07) to decrease from 2.9 to 2.1% of BW. Treatment did not affect estimated forage DMI (P = 0.40). Heifers receiving CSM1 gained 28.3% more BW than heifers receiving CON (47.27 vs. 36.82 kg, respectively; P = 0.02). Percent of BW gained was greater for heifers receiving CSM1 than CON (16.9 vs. 13.8% of initial BW, respectively, P = 0.029). There were no treatment by period interactions on IVTD or IVNDFD. The IVTD of forage from period 1 was greater than periods 2 and 3 (49.9 vs. 47.1 and 46.6%, respectively; P = 0.005). The IVTD of forage incubated with CSM tended (P = 0.06) to be greater than forage without CSM (52.1% vs. 47.8%, respectively). The IVNDFD was not affected by period but tended to be greater with CSM inclusion (P = 0.09) relative to CON (24.83% vs. 18.95%, respectively). In conclusion, 454 g/d of CSM supplemented to heifers grazing late-summer W.W. B-Dahl Bluestem forage likely provided sufficient protein to alter ruminal fiber digestibility, without affecting forage intake, and had measurable effects on gain.

Forage accumulation and nutritive value of four peanut (Arachis hypogaea L.) market types in the US Southern Great Plains

AbstractDual use crops are becoming popular as resources like land and water become scarcer. Annual peanuts are an important food crop grown worldwide that can also be used as forage or hay. Replicated trials evaluated the late season (≥15 weeks after planting) forage accumulations and nutritive values (acid detergent fiber, carbon content, crude protein, invitro true digestibility, neutral detergent fiber, nitrogen content, and relative feed value) of four market types near Clovis, NM and El Reno, OK in 2019 and 2020. Statistical analyses (p ≤ .05) showed all traits were affected by the interaction between market type and growing environment. Overall, forage accumulations for all market types ranged from 2.7 to 6.5 Mg ha−1 with relative feed values of 107–155. The location average across sites was 4.45 Mg ha−1 with relative feed value of 132. The Virginia market types produced large amounts of biomass. However, the Valencia market type generated the greatest nutritive values. This study indicates harvesting late‐season biomass of peanuts for hay may be an option that allows producers to generate more income from limited land and water resources. However, both market type and environmental factors, such as rainfall/irrigation, play important roles in production and forage nutritive values of peanut forage.

51 Estimation of in vitro digestibility measures within equine fecal inoculum using feedstuff fiber composition

Previous studies support the use of equine fecal microbes to simulate hindgut fermentation to calculate in vitro true digestibility (IVTD) of feedstuffs. Neutral detergent fiber (NDF) and acid detergent fiber (ADF) composition have been shown to predict IVTD, in vitro NDF digestibility (IVNDFD), and in vitro ADF digestibility (IVADFD). However, little work has been done to predict these digestibility measures within horses. Thus, the study objective was to determine correlation and estimation of in vitro digestibility measures using equine fecal inoculum from feedstuff NDF and ADF composition. Four mature stock-type geldings (8.5 ± 3.9yr; 558.4 ± 31.0kg; 6.0 ± 0.4 BCS) were used in a duplicated 4 × 6 Factorial Design. Horses were acclimated to a basal diet of 1.8% BW as-fed of Coastal Bermudagrass hay (Cynodon dactylon)and 0.2% BW as-fed of Bluebonnet® Equilene® Pellets for 21d. Feces were collected on d22 via rectal-grab for use as incubation inoculum. Dried, ground feed samples (0.5g: alfalfa hay, Coastal Bermudagrass hay, soybean meal, rice bran, hempseed meal, Bluebonnet® Equilene® Pellets), sealed in ANKOM filter bags, were placed in duplicate within 2 DaisyII incubators for 48hr. After incubation, fiber bags were removed and dried, then analyzed for NDF composition to determine IVTD. Split samples were analyzed to determine pre-incubation NDF composition of feedstuffs. Correlations and linearregressions were performed within R Statistical Program©. Both NDF (r = −0.936) and ADF (r = −0.897) were highly correlated to IVTD. However, ADF had a greater correlation to both IVNDFD (r = −0.807) and IVADFD (r = −0.848) than NDF (r = −0.684; r = −0.720). A linear regression between NDF and IVTD produced the model: IVTD (g/kg DM) = 1052.30 – 0.932 * NDF (g/kg DM); R2 = 0.930; P < 0.001. A lower goodness-of-fit was found between ADF and IVTD: IVTD (g/kg DM) = 1033.25 – 1.528 * ADF (g/kg DM); R2 = 0.866; P < 0.001. An additive model of IVTD versus NDF+ADF mildly increased goodness-of-fit (R2 = 0.953). Sample ADF strongly predicted IVADFD (IVADFD (g/kg ADF) = 881.91 – 1.595 * ADF (g/kg DM); R2 = 0.835; P < 0.001) but only moderately predicted IVNDFD (IVNDFD (g/kg NDF) = 855.15 – 1.518 * ADF (g/kg DM); R2 = 0.749; P < 0.001). These results indicate the effectiveness of using feedstuff NDF to predict IVTD when using equine fecal inoculum. Feedstuff IVNDFD and IVADFD are predicted with less precision, likely due to the lack of foregut digestion of feedstuffs that would occur in vivo. The use of in vitro total-tract digestion modeling in horses may estimate equine hindgut fiber digestion with greater precision.

77 In vitro true digestibility of hempseed meal using equine fecal inoculum

Digestibility of hempseed meal (Cannabis sativa L.; HSM) has been previously investigated in several livestock species as a protein source; however, data is lacking in horses. The study objective was to determine in vitro true digestibility (IVTD) of HSM compared with soybean meal (SBM), rice bran pellets (RBP), alfalfa hay (Medicago sativa; ALF), Coastal Bermudagrass hay (Cynodon dactylon; CBH), and a commercial concentrate (Bluebonnet® Equilene® Pellets; EQU). Four mature stock-type geldings (8.5 ± 3.9yr; 558.4 ± 31.0kg; 6.0 ± 0.4 BCS) were used in a duplicated 4 × 6 Factorial Design. Horses were acclimated to a basal diet of 1.8% BW as-fed of CBH and 0.2% BW as-fed of EQU for 21d. Fresh feces (400g) were collected on d22 via rectal-grab for use as incubation inoculum. Dried, ground feed samples (0.5g), sealed in ANKOM filter bags, were placed in duplicate within 2 DaisyII incubators for 48hr in fecal inoculum. After incubation, fiber bags were removed, dried (100°C for 2hr), then analyzed for neutral detergent fiber (NDF) composition to determine IVTD. Split samples were analyzed to determine pre-incubation NDF composition of feedstuffs. Data (mean ± SEM) were analyzed using a repeated measures ANOVA within R Statistical Program©. Significance was set at P ≤ 0.05. Hempseed meal NDF (440.2 ± 6.82 g/kg DM) was greater than ALF(330.8 ± 5.07; P < 0.001), RBP (219.0 ± 12.15; P < 0.001), and SBM (109.4 ± 6.17 g/kg DM; P < 0.001), yet lower than CBH (715.4 ± 10.77; P < 0.001) and tended to be higher than EQU (400.2 ± 8.29; P = 0.077). Feedstuff IVTD (g/kg DM) was greatest in SBM (962.9 ± 4.47) followed by RBP (857.8 ± 5.88) (P < 0.001). Alfalfa hay (742.6 ± 9.34) and EQU (757.2 ± 33.91) IVTD were similar (P = 0.962). Both ALF and EQU were decreased compared with RBP (P < 0.001) and greater than HSM (567.1 ± 4.93; P < 0.001) which was higher than CBH (401.4 ± 14.04; P < 0.001). These results indicate that HSM has an NDF content and IVTD between ALF and CBH, indicative of a lower digestibility compared with other proteinaceous feeds. This suggests potential for HSM to partially replace fiber sources in equine rations. High fat content in feedstuffs limits microbial fermentation of fiber, thus the fat content of HSM (107.0 g/kg DM), assumed to be digested in the foregut, may have limited microbial fiber digestion during in vitro incubation. Modified methods may be necessary to further assess IVTD of HSM in horses.

Forage-Yield and Nutrient Quality of New Brown Midrib (BMR) Mutant Lines of Sorghum

The objective of this study was to evaluate the yield, nutrient profile and in vitro digestibility of new BMR mutant lines of sorghum in Indonesia. These mutant lines were GH2.1, GH2.2, GH2.3, GH4.1, GH4.2, GH4.3 and GH4.4. One sorghum mutant line (CTY) and two national sorghum varieties (Super 1 and Bioguma) were also evaluated as controls. In vitro digestibility and rumen fermentation were measured using Ankom Daisy Fermenter and Hohenheim gas test methods, respectively. In vitro measurement consisted of ten treatments with five replications following a completely randomized design. The highest stem sugar content was found in Bioguma (11.22%) and GH4.4 (9.32%) (p<0.05). The Bioguma variety and the GH2.3 mutant line had a higher number of stem segments and fresh forage yield than the Super 1 variety (p<0.05). A greater concentration of crude protein (CP) was observed for the GH.2.1, GH2.2, GH2.3 and GH4.1 lines (p<0.05). The GH2.3 mutant line had the lowest acid detergent lignin (ADL) content (p<0.05), while Bioguma had the highest level of non-fibre carbohydrate (NFC) compounds (p<0.05). The highest relative feed value (RFV) was observed for the GH2.3 line (p<0.05). Furthermore, GH4.2 and GH2.3 had greater in vitro true digestibility (IVTD) (p<0.05) but were not significantly different from Bioguma. Regarding yield characteristics, nutrient composition and in vitro digestibility values, the highest values were found in the Bioguma variety and the GH2.3 mutant line. Except for n-valerate (nC5), significant differences in all rumen fermentation parameters were observed among sorghum cultivars (p<0.05). Regarding the interrelationship between parameters, we found a medium correlation of DMD with the ADL and cellulose content of sorghum forage (R2 = -0.489 and R2 = -0.674, respectively). Based on these findings, the GH2.3 BMR mutant line should be further developed as forage sorghum.

In Vitro Study of the Effect of Ensiling Length and Processing on the Nutritive Value of Maize Silages.

The effect of the ensiling length (3, 6, or 9 months), and the processing by dehydration (D) or dehydration and pelleting (P) with respect to the fresh silages (F) were studied in vitro on three maize cultivars in three incubation runs to study the effect of these factors on the nutritive value of maize silage. Gas production pattern, in vitro true digestibility (IVTD), methane concentration (6 and 12 h), ammonia, and volatile fatty acid concentration (VFA) at 12 h were measured. The moisture and pH of F averaged 676 g/kg and 4.09, respectively, and were not affected by the ensiling length, but moisture was reduced, and the pH increased in D and P with respect to F (p < 0.05). The ensiling length did not affect the chemical composition, but differences among the processing forms were detected in a higher acid detergent insoluble nitrogen (ADIN) proportion in P than D, and D than F (p < 0.001). Silages opened at 9 months showed the lowest gas production (p < 0.05), and those that opened after 3 months showed the highest IVTD. The effects of processing on nutrient utilisation only manifested on 3 month silages, with the volume of gas production and IVTD being lower in D than F. However, processing tended (p = 0.064) to reduce the methane proportion at 12 h, indicating both a more efficient fermentation and a lower potential of greenhouse gas emissions compared to the fresh silages. Extending the length of ensiling to 9 months reduced the fermentation of maize silage. The processing increased the dry matter and buffered the feed as well as contributed to an increase in fermentation in 3 month silages.

Effect of substituting steam-flaked corn for course ground corn on in vitro digestibility, average daily gain, serum metabolites and ruminal volatile fatty acids, and bacteria diversity in growing yaks

Yaks are well adapted to the Qinqhai-Tibetan Plateau and, traditionally, only grazed natural pasture all year without supplements. Today, however, yaks are also raised in feedlots; consequently, more information is needed in choosing optimal feeding regimes. This study examined the effects of substituting steam-flaked corn (SFC) for coarse ground corn (CGC) on average daily gain (ADG), in vitro true digestibility (IVTD), concentrations of ruminal volatile fatty acids (VFAs) and serum metabolites, and rumen bacterial diversity of growing yaks. Twenty-one, 2-year-old male yaks (138 ± 37.3 kg) were divided randomly into 3 groups (n = 7 per group) and received a total mixed ration (TMR) for 143 days. The TMR contained 446 g corn per kg dry matter (DM), but the ratio of CGC: SFC differed among the three groups as: 1) 100:0 (SFC0), 2) 50:50 (SFC50), and 3) 0:100 (SFC100). To maintain conditions similar to the feedlots, the yaks were fed as a group and feed intake was recorded daily. The yaks were weighed on 6 occasions during the study and ADG was calculated for each yak from the regression equation of body weight (BW) on days of treatment. On the morning of d 144 before feed was offered, jugular vein blood was collected to measure the concentrations of serum metabolites, and rumen contents were collected to determine ruminal VFAs, fermentation parameters and bacterial diversity. The daily dry matter intake (DMI) averaged between 6.08 and 6.15 kg per yak for the three dietary treatments and the IVTD increased with an increase in SFC (P < 0.05). The ADG was higher (P < 0.05) by 13.2% (812 vs 717 g/d) in the SFC100 group than in the SFC0 group while the ratio of the average daily DMI per yak to the average ADG per yak was lowest numerically for the SFC100 group (7.51), followed by the SFC50 group (8.46) and then the SFC0 group (8.66). The serum concentrations of alkaline phosphatase (ALP), serum urea-N, and triglycerides (TG) decreased (P < 0.05) but of aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and total cholesterol (TC) increased (P < 0.05) with an increasing proportion of dietary SFC. The greater serum concentration of LDH and lesser concentration of serum urea-N suggests that the SFC50 and SFC100 groups were proliferating cells at a faster rate and depositing more protein in muscle tissue than the SFC0 group, as the ADG increased with an increase in the level of dietary SFC. The ruminal concentrations of VFAs increased and of NH3-N decreased with an increase in the proportion of SFC. The rumen bacterial diversity did not differ among dietary groups; Bacteroidetes and Firmicutes were the dominant phyla and Prevotella and Succiniclasticum were the dominant genera in all dietary treatments. These results demonstrated that increasing the proportion of SFC could improve IVTD, ruminal concentration of VFAs, ADG and the group DMI to ADG ratio.

Comparative Transcriptome and Anatomic Characteristics of Stems in Two Alfalfa Genotypes.

Stems are more important to forage quality than leaves in alfalfa. To understand lignin formation at different stages in alfalfa, lignin distribution, anatomical characteristics and transcriptome profile were employed using two alfalfa cultivars. The results showed that the in vitro true digestibility (IVTD) of stems in WL168 was significantly higher than that of Zhungeer, along with the significantly lower neutral detergent fiber (NDF), acid detergent fiber (ADF) and lignin contents. In addition, Zhungeer exhibited increased staining of the xylem areas in the stems of different developmental stages compared to WL168. Interestingly, the stems of WL168 appeared intracellular space from the stage 3, while Zhungeer did not. The comparative transcriptome analysis showed that a total of 1993 genes were differentially expressed in the stem between the cultivars, with a higher number of expressed genes in the stage 4. Of the differentially expressed genes, starch and sucrose metabolism as well as phenylpropanoid biosynthesis pathways were the most significantly enriched pathways. Furthermore, expression of genes involved in lignin biosynthesis such as PAL, 4CL, HCT, CAD, COMT and POD coincides with the anatomic characteristics and lignin accumulation. These results may help elucidate the regulatory mechanisms of lignin biosynthesis and improve forage quality in alfalfa.

374 The Effects of Zinc Sulfate on the in Vitro Feed Digestibility in White-Tailed Deer

Abstract The captive white-tailed deer industry has an estimated economic impact of $1.6 billion, annually. However, nutritional requirements for cervids are determined through research based on sheep and goats. The objective of this study was to determine the effects zinc on in vitro dry matter digestibility for white-tailed does (Odocoileus virginianus). Does (n=2) were euthanized ethically, rumens were collected, and placed into a cooler containing warm water. Rumen contents were agitated and filtered using cheesecloth while applying CO2. The fluid was placed into four separate incubator jars with filter bags containing a 1:1 alfalfa to coastal hay blend. Zinc doses of 0.073 mg/kg/d were added to two of the jars (treatments), and the additional two jars received 0.00 mg/kg/d (control). Following 48 hours of incubation, in vitro true digestibility (IVTD) showed no significant differences (P &amp;gt;.05) between the control and treatment groups. Average dry matter digested in vitro was 91.87% and 95.13%; respectfully. Neutral detergent fiber (NDF) was no different (P &amp;gt;.05) between the two groups. The average digested NDF components for the control were 56.03% and the zinc group had a mean of 57.11%. Additionally, acid detergent fiber (ADF) did not statistically differ. The control group had an average of 74.56% for digested ADF components, and the treatment had a mean of 76.90%. No significant differences were observed in digested organic matter. The control group averaged 79.51% of digested organic matter (OM), and the treatment group averaged 79.38%. This methodology did prove to be viable and functional to evaluate microbial digestion in vitro. This study can be replicated with multiple experimental units to confirm the patterns of increased digestibility. Formal nutritional guidelines can be created to allow for more efficient feeding of deer. In turn, determining nutrient requirements for deer, reducing feed costs for operations, and continue educating the captive deer industry.

In Vitro Measurements of True Digestibility and Products of Digestion Using Multiple Cultivars of Non-Extracted and CBD-Extracted Industrial Hemp Biomass (Cannabis sativa)

Since 2018, the growth of industrial hemp (Cannabis sativa) for extraction of cannabidiol (CBD) oil has increased in popularity. By-products resulting from the extraction of the oil have become more available but remain largely unutilized due to their novelty and current restrictions on animal feeding. One potential use for the leftover inflorescence may be as a feedstuff, but reports examining its nutrient quality are limited. Therefore, experiments were conducted to evaluate 9 cultivars of non-extracted and 9 separate cultivars of CBD-extracted foliage. Ground alfalfa cubes were included in experiments as a control. All samples were analyzed for ash, ether extract, crude protein, lignin, ash-free neutral detergent fiber, acid detergent insoluble crude protein, and neutral detergent insoluble crude protein. Total digestible nutrients (TDN) were calculated using summative equations. In vitro true digestibility (IVTD) was determined using a filter bag technique and 48-h digestion period. Cumulative gas production was measured in batch culture over a 48-h period, with methane and ammonia production, volatile fatty acid (VFA) formation, and dry matter disappearance (DMD) measured following this period. Substrates for gas production measurements were composed of the hemp sample, rye silage, and ground corn mixed at a 30:35:35 ratio. Grind size (0.5 vs. 2.0 mm) was evaluated using non-extracted hemp and did not influence IVTD. Nutrient composition ranges of non- and CBD-extracted samples were similar, except for a numerically higher mean ether extract (17.66% vs. 9.29%) and TDN (73.01% vs. 54.03%) in non-extracted hemp. None of the measured nutrients for alfalfa cubes fell within the observed concentration ranges of either hemp group, but TDN was numerically similar to that of CBD-extracted hemp. IVTD was numerically similar between both hemp groups and alfalfa cubes. In comparison to alfalfa cubes, VFA (both concentration and molar proportions), ammonia concentrations, pH, DMD, methane, and total gas production were numerically similar with concurrently run non- and CBD-extracted hemp groups. The results of this study serve as a foundation from which a larger database of nutrient component values for hemp may be compiled. Such databases are necessary to fully evaluate the feasibility of a feedstuff for inclusion in animal diets.

Preservation Method of Rumen Fluid Collected From Harvested Cattle Alters in vitro Digestibility of Reference Feedstuffs

The objective of our experiment was to evaluate preservation and revitalization strategies for rumen inoculum anticipating research and veterinary applications. Rumen fluid samples were collected from 12 harvested cattle. Liquid samples were divided into five 500-mL aliquots which were randomly allocated to one of five treatments in a 2 × 2 + 1 augmented factorial design. Factors included preservation method [freezing (FZN) or lyophilization (LYO)] and preservative (glycerol; + or –). A fresh control (CON) was maintained from each sample. Feedstuffs used in this experiment were alfalfa hay, Coastal bermudagrass hay, cracked maize, rice bran, and soybean meal. Reference feedstuffs were subjected to batch culture in vitro true digestibility (IVTD) and in vitro NDF digestibility (IVNDFD) assays using inoculum from each of the five treatments. There was an effect (P &amp;lt; 0.05) of preservation method, preservative, and their interaction for both IVTD and IVNDFD of each of the five references feedstuffs. Freezing or lyophilization of rumen inoculum reduced (P &amp;lt; 0.05) IVTD and IVNDFD of reference feeds relative to the CON. Despite lower degradation of feeds when frozen or lyophilized rumen fluid was used rather than fresh, differences between them in IVTD and IVNDFD suggest that, in the absence of fresh inoculum, preserved rumen fluid may be a viable option for veterinary applications, such as transfaunation, but likely will not be viable for research applications.

Nutritive Value Variation of Paunch Manure as an Alternative Feed Ingredient.

Simple SummarySustainable livestock production is a benchmark for advancements in animal nutrition. Recovery of nutrients from products currently disposed of provides a potential solution to this mandate. Paunch manure is a potential novel feed ingredient comprised of digested feedstuffs at different stages of degradation, saliva, microorganisms, and products of fermentation. Thus, our objective was to determine the variability in nutritive values of dried paunch manure collected from harvested cattle. Animal-to-animal variation accounted for 30% to 75% of the variance in all measures of nutritive value. We believe that dried paunch manure may be a viable feed ingredient for inclusion in livestock rations, but a centralized composting system may be necessary to increase consistency.Ruminants, which have multi-compartmented stomachs, are adapted to digest cellulosic materials, which constitute the primary expense on ranches and dairies. Industrial byproducts can be repurposed for livestock diets to decrease these costs. Therefore, finding alternative feedstuffs may benefit the economics of livestock production. The goal of this project was to evaluate the variation in nutritive value of ruminal waste as a potential feedstuff. Twelve paunch samples were collected from individual cattle across multiple harvest dates at the Tarleton State University Meat Laboratory, Stephenville, TX. Samples were dried and assayed for dry matter (DM), crude protein (CP), sequential neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL), and physically-effective fiber (peNDF). Samples were subjected to batch-culture in vitro digestibility assays for the determination of digestibility coefficients. Mean NDF, ADF, ADL, CP and peNDF concentrations were 681, 399, 109, 150, and 387 g kg−1 DM, respectively. Contribution to variance from sample for NDF, ADF, ADL, CP, and peNDF were 75.3, 41.9, 33.0, 51.2, and 71.3%, respectively. In vitro true digestibility (IVTD) and in vitro NDF digestibility (IVNDFD) were recorded as 462 and 216 g kg−1 DM, respectively. Contribution to variation of sample for IVTD and IVNDFD were 31.0 and 30.7%, respectively. Results indicate that rumen waste harvested from abattoirs may be useful for sustainable livestock production, while reducing environmental threats posed by disposal, but the viability of the product is highly dependent on the source animal. For full viability of application in a sustainable system, a centralized receiving and compositing system may be useful for developing a consistent product.

Estimation of biomass and nutritive value of grass and clover mixtures by analyzing spectral and crop height data using chemometric methods

The study aims to estimate forage yield and quality parameters by fusing field spectroscopy data and crop height with regression-based mathematical models. Field experiments were carried out to obtain canopy spectral reflectance (CSR) of grass and clover mixtures. Additionally, grass height (Hgrass) and clover height (Hclover) were used as auxiliary explanatory variables with CSR to estimate forage yield and quality. Variable importance in projection (VIP) was utilized for sensitive wavelength selection. Two chemometric methods, namely partial least squares regression (PLSR) and support vector machine (SVM), were implemented to build models using full spectra and sensitive wavelengths for estimating dry matter yield (DMY), in vitro true digestibility (IVTD), neutral detergent fiber (NDF), neutral detergent fiber digestibility (NDFD), acid detergent fiber (ADF), acid detergent lignin (ADL), crude protein (CP), crude protein yield (CPY), and botanical composition (BC). Of the total 235 samples, 157 samples were randomly selected for model calibration while the remaining 78 samples were used for model validation. Results showed that both PLSR and SVM could reasonably estimate forage yield and quality variables, although performances of PLSR were more stable in terms of R2 and relative root mean square error (RRMSE) for both calibration and validation. Prediction performances of models using only full spectra data (PLSRspec) and models also using crop height information (PLSRspec+H) as model inputs were compared in this study. PLSRspec+H presented higher R2 and lower RRMSE than PLSRspec models (e.g. R2 improved from 0.83 to 0.90 for NDF and from 0.56 to 0.73 for IVTD, and RRMSE decreased from 8.14% to 6.58% for NDF and from 2.55% to 2.02% for IVTD). In addition, PLSR that used sensitive wavelengths and crop height (PLSRwave+H) as model inputs also had good performance, although slightly worse than PLSRspec+H. The results suggest that there is good potential to predict forage biomass and nutritive value by combining spectral and height variables with chemometric methods.

PSVII-15 Effects of electrolyzed reduced water on intake, digestion and ruminal fermentation parameters in beef cattle

Abstract The effect of electrolyzed reduced water consumption by cattle is not well defined. The objective of this study was to evaluate the effect of electrolyzed reduced water on intake, in vitro true digestibility (IVTD), ORP and pH in four ruminally cannulated steers (4 Bos taurus; 317 kg BW). Steers were subjected to a two period (14 d), two treatment crossover design. Treatment included: 1) standard water (CON; pH = 7.0 ± 1.0) or 2) electrolyzed reduced water (ERW; pH = 9.0 ± 1.0). The project comprised of two studies where the effects of ERW were observed for steers consuming a roughage diet (phase 1) or concentrate diet (phase 2). During Phase 1, animals were provided bermudagrass hay ad libitum. A 14 d transition period followed phase 1 to allow transition of diets. In phase 2, animals were maintained on a concentrate diet. During each period, d 1–8 served as a treatment adaptation phase, d 9–13 allowed for measures of intake and digestion, and rumen fluid was collected at h 0, 2, 4, 8, and 12 after feeding on d 14 for VFA, pH and ORP analysis. Data were analyzed using the MIXED procedure of SAS 9.4 (SAS Inst. Inc., Cary, NC). Intake, digestion, and ruminal fermentation parameters were not different for CON vs ERW steers (P ≥ 0.06). Analysis of VFA data have not been finalized and will be reported later. Results indicate that ERW has no effect on intake, digestion or ruminal fermentation parameters of steers consuming roughage or concentrate diets.

Partitioning of Forage Mass and Nutritive Value in Sunn Hemp Leaf and Stem Components

Sunn hemp (SH; Crotalaria juncea L.) is a fast-growing, annual, warm-season tropical legume that could complement less productive cool-season forages such as tall fescue during summer. Little is known about seasonal forage mass and nutritive value partitioning in SH plant components when SH is managed for forage. We determined partitioning of forage mass and nutritive value (crude protein (CP), in vitro true digestibility (IVTD), neutral detergent fiber (NDF), acid detergent fiber (ADF), and neutral detergent fiber digestibility (NDFD)) concentrations in SH leaves and stems harvested 35, 45, and 55 days after planting (DAP) at Bradford Research Center, Columbia, MO, in a 2-year field study. Leaf and stem mass increased with increasing DAP and was greatest ( P ≤ 0.05 ) at 55 DAP followed by 45 and 35 DAP. Stems contributed most to the total forage mass beyond 45 DAP. Across years, CP was greatest ( P ≤ 0.05 ) in leaves (281 g kg−1 DM) and lowest for stems (81 g kg−1 DM) at 55 DAP. The lowest NDF ( P ≤ 0.05 ) was observed in leaves (251 g kg−1 DM) and stems (585 g kg−1 DM) at 35 DAP. Acid detergent fiber was lowest ( P ≤ 0.05 ) for SH leaves (178 g kg−1 DM) and stems (484 g kg−1 DM) at 35 DAP. Digestibility of leaves was greater than that of stems and generally decreased with maturity. The nutritive value of leaves was consistently greater than that of stems and decreased with maturity, except for CP of leaves, which was maintained throughout the season. Results suggested that SH leaves can maintain forage mass and greater quality than its stem throughout the growing season.

The Effects of Different Forage Types on Feed Values and Digestibilities in Some Brassica Fodder Crops

This study was conducted to explore the effects of different forage types (fresh, hay and silage) on the chemical composition, forage quality and in vitro true digestibility (IVTD) of fodder turnip (Brassica rapa), fodder mustard (Brassica nigra) and canola (Brassica napus L.). Ankom Daisy incubator was used to determine the IVTD and forages were incubated for 48 hours. According to the findings of this study, canola silage and mustard silage have the highest ether extract (EE) content, while mustard silage has the highest crude protein (CP) content (P&amp;lt;0.001). It was found that, among the samples, turnip silage has the highest value in terms of neutral detergent fiber (NDF) content; mustard grass, turnip grass and canola hay have higher values in terms of lignin content while mustard silage has the lowest lignin content. As a result, it was concluded that grass, hay and silage obtained from Brassica fodder crops could be used as alternative forage souces. However, use of Brassica silages is recommended in ruminant nutrition.

EVALUATING THE POTENTIAL OF TRIDAX PROCUMBENS FOR LIVESTOCK FEED

Seasonal changes in chemical composition represented by crude protein (CP), In vitro true digestibility (IVTD), and fibre components measured by neutral detergent fibre (NDF), acid-detergent fibre (ADF) and lignin were evaluated at specified cano­py ages and stages of maturity in Tridax procumb ens. Samples were selected from five harvest dates in April, June, August, October, and December. Chemical com­position was: highly responsive to dates of harvest. The stage of maturity of canopies reached significantly higher values in August than in the other months of the year. Asso­ciated with these were-lower CP and IVTD and high NDF, ADF and lignin. The poten­tial value of Tridax prOcumbens lies in a pro­perly structured management system that optimises its quality attributes.