Fermentation Pattern Research Articles

In vitro rumen fermentation characteristics of bakery by-products containing high starch and sugar.

The objectives of this study were to evaluate the nutritional characteristics of bakery by-products (castella, pancake, baumkuchen) and their effect on rumen fermentation in vitro as compared with steam-flaked corn and barley as human-edible grains. The fermentation pattern of sugar and starch as pure components was also investigated. Additionally, rumen pH was evaluated using a low-capacity buffer. Bakery by-products contained high sugar (212-590 g/kg DM) and starch (262-545 g/kg DM). Castella exhibited the highest sugar content, whereas pancake and baumkuchen were rich in starch and ether extract within bakery by-products, respectively. The gas production rate at the early phase of incubation was higher in bakery by-products than in grains, and the highest in castella among all feeds. Bakery by-products produced higher total organic acids and propionate than grains. Bakery by-products also exhibited a lower rumen pH than grains during twenty-four hours of incubation with a low-capacity buffer. As pure components, sucrose showed a higher gas production rate and lower pH than starch. Overall, compared with grains, bakery by-products have the potential not only to supply more energy to ruminants but also decrease rumen pH because sugar and starch in bakery by-products ferment rapidly and produce higher organic acids in the rumen.

Partially substituting alfalfa hay with hemp forage in the diet of goats improved feed efficiency, ruminal fermentation pattern and microbial profiles

The use of hemp as a forage source in livestock diets has been less studied because bioactive residues in animal tissues may pose a risk to consumers. This study investigated the effects of partial substitution of alfalfa hay (AH) with hemp forage (HF) in growing goat diets on growth performance, carcass traits, ruminal fermentation characteristics, rumen microbial communities, blood biochemistry, and antioxidant indices. Forty Xiangdong black goats with body weight (BW) 7.82 ± 0.57 kg (mean ± SD) were grouped by BW and randomly assigned into one of the four treatment diets (n = 10/treatment) in a completely randomized design. The goats were fed ad libitum total mixed rations containing 60% forage and 40% concentrate (DM basis). The diets included control (CON; 60% AH and 40% concentrate), 55% AH and 5% HF (HF5), 50% AH and 10% HF (HF10), and 40% AH and 20% HF (HF20). Increasing the substitution of HF for AH linearly decreased (P = 0.004) DM intake and improved feed conversion efficiency. However, final BW, average daily gain, carcass traits, meat quality, and most blood biochemistry indices did not differ among treatments. The ruminal NH3-N concentration (P = 0.003) and blood urine nitrogen (P = 0.050) linearly increased (P < 0.01) with increasing substitution rate of HF, whereas the total volatile fatty acids concentration quadratically changed (P = 0.007). Substitution of AH with HF had no effect on the diversity and richness of ruminal microbes, though it linearly decreased (P = 0.040) Prevotella_1 and linearly increased (P = 0.017) Rikenellaceae_RC9_gut_group. The cannabinoids and/or their metabolites were detected in both ruminal filtrates (8) and plasma (4), however, no detectable cannabinoid-related residues were observed in meat. These results indicate that the HF could be used to partially substitute AH in goat diets, whereas the effects vary between substitution rates of HF for AH. Although no cannabinoid-related residues were detected in meat, the presence of cannabinoids residues in blood warrants further study of HF feeding to confirm the cannabinoids residues are not present in the animal products.

Comparison of the Chemical and Microbial Composition and Aerobic Stability of High-Moisture Barley Grain Ensiled with Either Chemical or Viable Lactic Acid Bacteria Application

This experiment was aimed at comparing how a chemical additive or an inoculant would affect the dry matter (DM) losses, fermentation pattern, yeast and mold counts, and aerobic stability (AS) of the ensiled high-moisture barley grain (675 g kg−1 DM). Crimped barley grain was ensiled with or without chemical additive AIV Ässä Na and an inoculant SiloSolve FC, totaling three treatments (1 × 3 factorial scheme) for the fermentation periods lasting 7, 14, 28, 60, and 90 days. The application of a chemical additive showed higher pH levels, retained water-soluble carbohydrates (WSCs) better, lowered DM loss, and reduced concentrations of fermentation products. Barley grain treated with chemicals initially showed a marked reduction in yeast and fungal growth and a higher AS up to day 60 of storage but became less effective in later stages of storage, leading to decreased AS. Barley grain inoculated with homo- and heterofermentative strains had decreased silage pH; its WSC content was similar to control and had higher content of weak acids and 1,2 propanediol, reducing mold and yeast counts. With fermentation duration from 28 days and beyond (i.e., 90 days), the inoculant treatment achieved the longest AS and the lowest increase in pH and weight loss during the period of air exposure.

Dietary incorporation of magnetic bentonite nanocomposite: impacts on in vitro fermentation pattern, nutrient digestibility, and growth performance of Baluchi male lambs.

Incorporation of bentonite into the diets of ruminants can be helpful to maximize their performance. Modifying the structure of bentonite to nano and nanocomposite has improved their chemical stability and physicochemical properties, enhancing adsorption, absorption, and cation exchange capacity. Aims: This study aimed to assess the effect of magnetic bentonite nanocomposite (MBNC) on in vivo and in vitro fermentation process patterns, nutrient digestibility, and growth performance of Baluchi male lambs. Effects of control (basal diet), natural bentonite (NB) (10 g/kg dry matter (DM)), processed bentonite (PB) (5 and 10 g/kg DM basal diet), and MBNC (5 and 10 g/kg DM basal diet) on gas production (GP), and the fermentation process were determined using in vitro GP technique. For the in vivo experiment, 20 Baluchi male lambs were used with 4 experimental treatments: control, NB (5 g/kg DM), PB (5 g/kg DM), and MBNC (5 g/kg DM) and 5 replications in a completely randomized design for 60 consecutive days. The potential for GP and its fractional rates were significantly decreased and increased in MBNC, respectively (P<0.01). The lowest cumulative GP, and CH4 yield were observed in MBNC (P<0.05). In vitro, DM and organic matter (OM) digestibility and all fermentation parameters increased with the addition of two levels of MBNC to the culture medium (P<0.01). Except for feed conversion ratio (FCR), other growth performance parameters increased with the addition of MBNC to the diet (P<0.01). The ruminal pH, total volatile fatty acids (TVFA), acetate, and propionate significantly increased when MBNC incorporated to the diet (P<0.01). The NH3-N (P<0.001) was significantly decreased in MBNC. The bentonite supplementation decreased acetate to propionate (P=0.001) compared to the control. Adding MBNC at the 5 g/kg diet DM level can be used as a useful supplement to optimize rumen fermentation pattern, reduce methane production, and increase lamb performance.

Effect of supplementing herbal feed additives on the fermentation pattern and In vitro methane production by total mixed rations with different roughage to concentrate ratios

Effect of supplementing herbal feed additives on the fermentation pattern and In vitro methane production by total mixed rations with different roughage to concentrate ratios

Produção de gases “in vitro” de cultivares de milheto sob doses de nitrogênio

ABSTRACT This study aimed to evaluate the in vitro gas production from three pearl millet cultivars submitted to four nitrogen levels. The treatments consisted of three pearl millet cultivars (ADR 500, ADR 7020, and LABH 70732) and four nitrogen levels (0, 50, 100, and 200 kg/ha), using urea as the nitrogen source. A 3 x 4 factorial experimental design, employing a randomized block setup, was used to assess both gas production and digestibility. No interaction was observed between nitrogen doses and fermentative parameters on in vitro gas production from the dry matter of pearl millet cultivars. Nitrogen had no impact on the dry matter content or chemical composition of the cultivars. Consistency prevailed in the chemical composition across the various cultivars, a trend that extended to the gas production rates for both soluble and insoluble contents. Notably, nitrogen fertilizer exerted an influence on the fermentation pattern of organic matter, gas production, and lag time for the cultivars. Nitrogen fertilization is advised solely for enhancing fermentative attributes in the case of the cultivar ADR 7020.

Dynamic changes in carbohydrate components and the bacterial community during the ensiling of wilted and unwilted sweet sorghum.

Sweet sorghum can be used to produce a substantial quantity of biofuel due to its high biological yield and high carbohydrate content. In this study, we investigated the dynamic changes in fermentation characteristics, carbohydrate components, and the bacterial community during the ensiling of wilted and unwilted sweet sorghum. The results revealed a rapid fermentation pattern and high-quality fermentation quality in wilted and unwilted sweet sorghum, wherein lactic acid, and acetic acid accumulated and stabilized during the initial 9 days of ensiling, with the pH values less than 4.2, until 60 days of ensiling. We found that the ensiling of sweet sorghum involved the degradation (5% ~ 10%) of neutral detergent fiber (NDF) and hemicellulose and that the degradation of NDF fit a first-order exponential decay model. A shift in dominance from Lactococcus to Lactobacillus occurred before the first 9 days of ensiling, and the abundance of Lactobacillus (r = -0.68, p < 0.001) was negatively correlated with the NDF content. The relative abundances of Lactobacillus in wilted and unwilted sweet sorghum after ensiling for 60 days were 76.30 and 93.49%, respectively, and relatively high fermentation quality was obtained. In summary, ensiling is proposed as a biological pretreatment for sweet sorghum for subsequent biofuel production, and unlike other materials, sweet sorghum quickly achieves good fermentation quality and has great potential for bioresource production.

Effect of feeding high concentrate ration on blood-biochemistry and rumen fermentation pattern of sheep

Effect of feeding high concentrate ration on blood-biochemistry and rumen fermentation pattern of sheep

Ecological versatility and biotechnological promise: Comprehensive characterization of the isolated thermophilic Bacillus strains.

This study focuses on isolated thermophilic Bacillus species' adaptability and physiological diversity, highlighting their ecological roles and potential industrial applications. We specifically investigated their capacity to thrive in extreme conditions by examining their environmental tolerances and adaptations at the metabolic and genetic levels. The primary objective is to evaluate the suitability of these species for biotechnological applications, considering their resilience in harsh environments. We conducted a comparative analysis of the environmental adaptability parameters for various Bacillus species. This included examining growth temperature ranges, pH tolerance, oxygen requirements, carbohydrate fermentation patterns, colony morphology, enzymatic activities, and genetic properties. Controlled laboratory experiments provided the data, which were then analyzed to determine patterns of adaptability and diversity. The research revealed that Bacillus species could endure temperatures as high as 73°C, with a generally lower growth limit at 43°C. However, strains TBS35 and TBS40 were exceptions, growing at 37°C. Most strains preferred slightly alkaline conditions (optimal pH 8), but TBS34, TBS35, and TBS40 exhibited adaptations to highly alkaline environments (pH 11). Oxygen requirement tests classified the species into aerobic, anaerobic, and facultative aerobic categories. Genetic analysis highlighted variations in DNA concentrations, 16s rRNA gene lengths, and G+C content across species. Although glucose was the primary substrate for carbohydrate fermentation, exceptions indicated metabolic flexibility. The enzymatic profiles varied, with a universal absence of urease and differences in catalase and oxidase production. Our findings underscore thermophilic Bacillus species' significant adaptability and diversity under various environmental conditions. Their resilience to extreme temperatures, pH levels, varied oxygen conditions, and diverse metabolic and genetic features emphasize their potential for biotechnological applications. These insights deepen our understanding of these species' ecological roles and highlight their potential industrial and environmental applications.

Valor nutritivo e características fermentativas da silagem de milheto com diferentes níveis de casca de café

ABSTRACT: The research was conducted to test the hypothesis that the inclusion of coffee husk (Coffea sp.) would improve the fermentative characteristics and quality of pearl millet silage (Pennisetumglaucum). Thus, the objective was to assess the effect of the inclusion of different levels of coffee husk in pearl millet silage on the chemical composition, fermentative characteristics and degradability in situ of silage. The experimental design used was completely randomized and the treatments consisted of the silage of the whole pearl millet plant with the inclusion of increasing levels of coffee husk: 0%, 7%, 14% and 21%, based on natural matter. After 60 days of fermentation, the silages were evaluated for chemical characteristics, fermentative, degradability in situ dry matter (DM) and neutral detergent fiber (NDF). The inclusion of coffee husk did not alter (P &gt; 0.05) the contents of crude protein (11.94%), NDF (44.89%) and total digestible nutrients (65.09%). There were increases in the concentrations of DM and fiber in acid detergent, accompanied by a reduction in the concentrations of mineral matter and ether extract, as the proportion of coffee husks in silages increased. There was an increase in the lignin content up to the level of 7.59% inclusion of the coffee husk. There was no effect of the inclusion of the coffee husk on the pH of the silage (3.60). However, the inclusion of coffee husk resulted in a reduction in temperature, gas losses, and degradability in situ of silage DM and NDF. It is recommended to include coffee husk up to the level of 14.0% of the natural matter to improve the fermentation pattern and the quality of the pearl millet silage.

Enhancing rumen microbial diversity and its impact on energy and protein metabolism in forage-fed goats.

This study explores if promoting a complex rumen microbiota represents an advantage or a handicap in the current dairy production systems in which ruminants are artificially reared in absence of contact with adult animals and fed preserved monophyte forage. In order to promote a different rumen microbial diversity, a total of 36 newborn goat kids were artificially reared, divided in 4 groups and daily inoculated during 10 weeks with autoclaved rumen fluid (AUT), fresh rumen fluid from adult goats adapted to forage (RFF) or concentrate (RFC) diets, or absence of inoculation (CTL). At 6 months of age all animals were shifted to an oats hay diet to determine their ability to digest a low quality forage. Early life inoculation with fresh rumen fluid promoted an increase in the rumen overall microbial diversity which was detected later in life. As a result, at 6 months of age RFF and RFC animals had higher bacterial (+50 OTUs) and methanogens diversity (+4 OTUs) and the presence of a complex rumen protozoal community (+32 OTUs), whereas CTL animals remained protozoa-free. This superior rumen diversity and presence of rumen protozoa had beneficial effects on the energy metabolism allowing a faster adaptation to the forage diet, a higher forage digestion (+21% NDF digestibility) and an energetically favourable shift of the rumen fermentation pattern from acetate to butyrate (+92%) and propionate (+19%) production. These effects were associated with the presence of certain rumen bacterial taxa and a diverse protozoal community. On the contrary, the presence of rumen protozoa (mostly Entodinium) had a negative impact on the N metabolism leading to a higher bacterial protein breakdown in the rumen and lower microbial protein flow to the host based on purine derivatives urinary excretion (-17% to -54%). The inoculation with autoclaved rumen fluid, as source of fermentation products but not viable microbes, had smaller effects than using fresh inoculum. These findings suggest that enhancing rumen microbial diversity represents a desirable attribute when ruminants are fed forages in which the N supply does not represent a limiting factor for the rumen microbiota.

In vitro ruminal-microbial fermentation pattern: nutritional insights about some agricultural crop mesocarps (peel) in ruminant nutrition

Different agricultural crop wastes (ACW) such as mesocarps (peel) are annually produced after consuming their edible parts in the world without any scientific information about their nutritional potential. Therefore, a study was conducted to determine the ruminal-microbial fermentation pattern and nutritional potential of some crop mesocarps (peel) including different species of melons (Watermelon, Galia melon, Rockmelon, Til sabz, and Til atashi) as well as cucumber and eggplant using common and standard laboratory methods. The amount of crude protein (CP) varied from 7.19 to 19.1% of dry matter (DM) for Til sabz and cucumber mesocarps, respectively. The highest (34.1% of DM) and lowest (15.4%) content of neutral detergent fiber (NDF) were related to eggplant and Til sabz peels, respectively (p < 0.05). The content of non-fiber carbohydrates (NFC) varied from 38.7% for eggplant peel to 66.6% for Til sabz. All mesocarps had a low DM percentage (4.88% of DM for cucumber to 8.45 for eggplant). Rockmelon peel had the highest amount of calcium (5.25 g/kg DM) and magnesium (5.75 g/kg DM) compared with the other mesocarps (p < 0.05). The highest amounts of potassium (33.4 g/kg of DM), sodium (7.15 g/kg of DM), and zinc (21 mg/kg of DM) were observed in the peels of watermelon, Til atashi, and cucumber, respectively (p < 0.05). The potential of ruminal-microbial gas production also differed from 55.6 ml/200 mg of DM for eggplant to 63.1 ml for Til sabz peel. Except for cucumber (8.75 MJ/kg of DM) and eggplant (8.71 MJ), other mesocarps (different melon species) had almost similar metabolizable energy (ME, 9.06–9.50 MJ/kg of DM). Among the studied mesocarps, the lowest ruminal-microbial DM and organic matter (OM) digestibility was also observed in eggplant and cucumber (p < 0.05). Gallia melon had the highest acid-base buffering capacity (267 mEq×10− 3, p < 0.05). According to our findings, the mesocarps of melons showed a higher nutritional value than the cucumber and eggplant. In general, Til sabz exhibited a notable favorite and superior nutritional characteristic compared with the other mesocarps.

Yeast culture repairs rumen epithelial injury by regulating microbial communities and metabolites in sheep.

This study delves into the impact of yeast culture (YC) on rumen epithelial development, microbiota, and metabolome, with the aim of investigating YC's mechanism in regulating rumen fermentation. Thirty male lambs of Hu sheep with similar age and body weight were selected and randomly divided into three groups with 10 lambs in each group. Lambs were fed a total mixed ration [TMR; rough: concentrate (R:C) ratio ≈ 30:70] to meet their nutritional needs. The experiment adopted completely randomized design (CRD). The control group (CON) was fed the basal diet with high concentrate, to which 20 g/d of YC was added in the low dose YC group (LYC) and 40 g/d of YC in the high dose YC group (HYC). The pretrial period was 14 days, and the experimental trial period was 60 days. At the end of a 60-day trial, ruminal epithelial tissues were collected for histomorphological analysis, and rumen microorganisms were analyzed by 16S rDNA sequencing and rumen metabolites by untargeted liquid chromatography-mass spectrometry (LC-MS) metabolomics techniques. The results showed that YC improved rumen papilla development and increased rumen papilla length (p < 0.05), while decreased cuticle thickness (p < 0.05). The 16S rDNA sequencing results showed that YC reduced the relative abundance of Prevotella_1 (p < 0.05), while significantly increased the relative abundance of Ruminococcaceae_UCG-005, uncultured_bacterium_f_Lachnospiraceae, and Ruminococcus_1 genus (p < 0.05). Metabolomics analysis showed that YC changed the abundance of metabolites related to amino acid metabolism, lipid metabolism and vitamin metabolism pathways in the rumen. In summary, YC might maintain rumen health under high-concentrate diet conditions by changing rumen microbiota structure and fermentation patterns, thereby affecting rumen metabolic profiles and repairing rumen epithelial injury.

Effects of dietary wheat supplementation levels on growth performance, rumen bacterial community and fermentation parameters in Chinese Tibetan Sheep.

The objective of this study was to evaluate various wheat supplementation levels on rumen microbiota and fermentation parameter in Tibetan sheep. A total of ninety ram with an average 12.37 ± 0.92 kg at the age of 2 months were randomly allocated to three treatments: 0% wheat diet (CW, N = 30), 10% wheat diet (LW, N = 30), and 15% wheat diet (HW, N = 30) on a dry matter basis. The experiment was conducted over a period of 127 days, including 7 days of adaption to the diets. Our results showed that sheep fed 10% wheat exhibited optimal average daily gain and feed gain ratio compared with HW group (p < 0.05). The serum alkaline phosphatase concentration was the lowest when fed the 10% wheat diet (p < 0.05), whereas serum aspartate aminotransferase concentration was the highest (p < 0.05). Both acetate and propionate increased with increase in dietary wheat ratio (p < 0.05), while a greater decrease in concentrations of NH3 -N was observed (p < 0.05). In rumen fluid, 3413 OTUs were obtained with 97% consistency. Phylum Firmicutes was the predominant bacteria and accounted for 49.04%. The CW groups supported significantly increased the abundance of Bacteroidetes (p < 0.05), as compared with the HW group. The abundance of Bacteroidales_UCG-001, Ruminococcus, and Mitsuokella possessed a higher relative abundance in HW group (p < 0.05). No differences in the bacterial community and fermentation parameters were observed between the sheep fed 0% and 10% wheat (p > 0.05). Ruminal bacterial community structure was significantly correlated with isobutyrite (r2 = 0.4878, p = 0.035) and valerate (r2 = 0.4878, p = 0.013). In conclusion, supplementation of 10% wheat in diet promoted the average daily gain and never altered microbial community structure and fermentation pattern, which can be effectively replace partial corn in Chinese Tibetan Sheep.

Comparison of the effects of rumen-protected and unprotected L-leucine on fermentation parameters, bacterial composition, and amino acids metabolism in in vitro rumen batch cultures

This study was conducted to compare the effects of rumen-protected (RP-Leu) and unprotected L-leucine (RU-Leu) on the fermentation parameters, bacterial composition, and amino acid metabolism in vitro rumen batch incubation. The 5.00 g RP-Leu or RU-Leu products were incubated in situ in the rumen of four beef cattle (Bos taurus) and removed after 0, 2, 4, 6, 12, 16, and 24 h to determine the rumen protection rate. In in vitro incubation, both RP-Leu and RU-Leu were supplemented 1.5 mmol/bottle (L-leucine HCl), and incubated after 0, 2, 4, 6, 8, 12, and 16 h to measure gas production (GP), nutrient degradability, fermentation parameters, bacterial composition, and amino acids metabolism. Results from both in vitro and in situ experiments confirmed that the rumen protection rate was greater (p &amp;lt; 0.01) in RP-Leu than in RU-Leu, whereas the latter was slow (p &amp;lt; 0.05) degraded within incubation 8 h. Free leucine from RP-Leu and RU-Leu reached a peak at incubation 6 h (p &amp;lt; 0.01). RU-Leu supplementation increased (p &amp;lt; 0.05) gas production, microbial crude protein, branched-chain AAs, propionate and branched-chain VFAs concentrations, and Shannon and Sobs index in comparison to the control and RP-Leu supplementation. RU-Leu and RP-Leu supplementation decreased (p &amp;lt; 0.05) the relative abundance of Bacteroidota, which Firmicutes increased (p &amp;lt; 0.05). Correlation analysis indicated that there are 5 bacteria at the genus level that may be positively correlated with MCP and propionate (p &amp;lt; 0.05). Based on the result, we found that RP-Leu was more stable than RU-Leu in rumen fluid, but RU-Leu also does not exhibit rapid degradation by ruminal microbes for a short time. The RU-Leu was more beneficial in terms of regulating rumen fermentation pattern, microbial crude protein synthesis, and branched-chain VFAs production than RP-Leu in vitro rumen conditions.

Effect of Fermented Concentrate on Ruminal Fermentation, Ruminal and Fecal Microbiome, and Growth Performance of Beef Cattle

The impact of fermented concentrate on the growth and rumen health of beef cattle remains an area of emerging research. This study aimed to assess the influence of a fermented concentrate (TRT) compared to a conventional concentrate (CON) on the growth, rumen fermentation characteristics, and microbiota composition in Korean cattle. Using a crossover design, eight cattle were alternately fed TRT and CON diets, with subsequent analysis of feed components, rumen fermentation parameters, and microbial profiles. TRT and CON diets did not differ significantly in their effect on animal growth metrics. However, the TRT diet was associated with reduced digestibility of rapidly degradable carbohydrates and modified rumen fermentation patterns, as evidenced by an elevated pH and increased acetate-to-propionate ratio (p &lt; 0.05). Furthermore, the TRT diet increased the abundance of lactic acid bacteria, Bacillus, and yeast and organic acid levels in the rumen (p &lt; 0.05). Moreover, Lachnospiraceae and Bacteroidales populations in the rumen and fecal Akkermansia abundance increased in the TRT group compared to the CON group. These microbial changes suggest a potential enhancement of the immune system and overall health of the host. Further research on the long-term implications of incorporating fermented concentrate into cattle diets is warranted.

Conventional Feed-Grade or Slow-Release Coated Urea as Sources of Dietary Nitrogen for Fattening Lambs.

Twenty-two Assaf male lambs (29.2 ± 0.9 kg live weight and 89 ± 0.2 days of age), distributed in two experimental groups, were used to evaluate the use of either feed-grade conventional urea (Control diet; n = 11) or slow-release urea (SRU diet; n = 11) as sources of dietary nitrogen on animal performance, ruminal fermentation, blood acid-base status, plasmatic metabolic profile, and carcass and meat quality. Animals were housed individually and fed ad libitum. At the end of the fattening period (day 70), the animals were slaughtered to compare the fermentation patterns in ruminal digesta and to evaluate the carcass and meat characteristics. No statistically significant differences (p > 0.05) were observed between treatments in the dry matter intake, final live weight, average daily gain, and feed conversion rate. Regarding the ruminal fermentation parameters, the molar proportion of propionic acid was higher (p < 0.05) and that of butyric acid was lower (p < 0.05) with the SRU than with the Control diet. There were no significant differences (p > 0.05) between experimental treatments in the blood acid-base status and biochemical profile, except for the concentration of urea in plasma, which was significantly (p < 0. 05) greater in SRU than in Control lambs. No statistically significant differences were observed between treatments (p > 0.05) in the carcass and meat characteristics. In conclusion, the use of slow-release urea as a replacement for feed-grade conventional urea in the diet of Assaf fattening lambs, under the experimental conditions of this study, did not improve animal performance and increased the feeding costs.

PSIV-5 High Desert Hemp Varieties Under Varied Nitrogen Fermentation Techniques Effects on Its Utilization as Livestock Feed Through in Vitro Fermentation

Abstract Nitrogen fertilizing of hemp varietals in high the high desert may assist in ensuring that production levels match the demand for growing hemp varietals. However, altering fertilizer levels may differently affect plant biomass and cannabinoid concentrations of plant tissues which changes the potential by-product utilizable for livestock feed. This study aimed to determine the influence of hemp fractions [flower (FL) vs stem and leaves (SL)] under three nitrogen fertilization regimens (0, 100, and 200 kg· ha-1) on in vitro rumen fermentation. Incubations runs consisted of triplicates of 500-mL bottles containing approximately 0.5 g of either ground SL or FL of hemp at the three nitrogen fertilization regimens. Rumen fluid was collected from two ruminally cannulated Angus steers, filtered through four layers of cheesecloth, and diluted to 4:1 with a standard buffer solution. A total incubation volume of 75 mL of the buffer: rumen fluid mix was added to each flask. Flasks were then placed in a rotating incubator (55 rpm) at 39°C, connected to an Ankom RF gas production system (Ankom Technology, Macedon, NY), and removed after 24, 48, and 96h. Total gas production (TGP), metabolizable energy (ME), ammonia nitrogen concentration (N-NH3), and total volatile fatty acids (VFA) were determined. Data were analyzed as a completely randomized design using lmer function in lme4 package in R with treatment and time as a fixed effect and replicates as a random effect. Statistical significance was established at P &amp;lt; 0.05 (Table 1). No differences were observed for N-NH3 (P &amp;gt; 0.05). Overall, SL samples had greater total VFA than FL, with T0SL having the greatest concentration among all treatments (P &amp;lt; 0.01). In congruence, acetate, isobutyrate, isovalerate, and the ratio between acetate and propionate concentrations were also greater for T0SL (P &amp;lt; 0.01). Concentrations of butyrate were greater for T200SL (P &amp;lt; 0.01), while T100SL had the greatest concentration of butyrate among all the treatments (P &amp;lt; 0.01). Overall, SL fractions of hemp seem to be more suitable as a ruminant feed source. The greater fat content of the FL compared with SL may detrimentally affect microbial populations and should further be explored. From our results, N supplementation significantly alters fermentation patterns during in vitro, which further warrants the evaluation of these feeds on in vivo experiments.

Standardisation of the C:N ratio in ileal digesta changes relationships among fermentation end-products during in vitro hindgut fermentation in pigs

Undigested proteins that become available for the microbiota in the hindgut can be used as building blocks for bacterial cells, or can enter various catabolic pathways. Degradation via protein fermentation pathways is least preferred, as several fermentation end-products released can be toxic for the host. Directing microbial protein metabolism towards protein synthesis or degradative pathways that result in less toxic end-products, for example through nutritional interventions, is an interesting strategy for improving health. We studied variation in protein fermentation patterns, resulting from variation in substrate composition. Ileal digesta, obtained from cannulated pigs fed different protein sources, were subjected to fermentation in vitro under different conditions; (1) ileal digesta were fermented as-is, (2) ileal digesta were fermented after standardisation to a constant high C:N ratio, by addition of high fermentable carbohydrates and (3) ileal digesta samples were incubated under limiting N concentrations. Gas production was monitored as an indirect measure of microbial activity, and fermentation end-products at different points in time were analysed by gas chromatography and high resolution mass spectrometry. Using principal component analysis, we identified patterns in protein fermentation end-products and related them to the composition of ileal digesta. Protein-associated fermentation end-product concentrations of e.g. isovaleric-, isobutyric-, phenylacetic acid and p-cresol were negatively affected by the available amount of high fermentable carbohydrates combined with a high C:N ratio. The aforementioned fermentation end-products positively correlated with NH3 concentrations and negatively with short-chain fatty acid (SCFA) concentrations. Standardisation to a constant high C:N ratio changed their relationship; isovaleric-, isobutyric-, phenylacetic acid and p-cresol lost their correlation with NH3 concentrations, became positively correlated with SCFA concentrations, and now showed a positive correlation with available amounts of high fermentable carbohydrates. Our observations demonstrate an important role of the C:N ratio in the relationship between fermentation end-products. At constant C:N, protein fermentation end-products correlate with end-products of carbohydrate fermentation and NH3, often considered as a proxy for protein fermentation, loses its predictive power.

Effects of particle size and storage length on the fermentation pattern and ruminal disappearance of rehydrated corn grain silage hammer mill processed

The aim of this study is to determine whether the particle size interacts with the storage length to affect the fermentation pattern and the ruminal disappearance of rehydrated corn grain silage (RCGS). It was also assessed whether particle size affects the minimum storage time in relation to the disappearance of ruminal dry matter (DMD). The treatments consisted of six mean particle sizes of RCGS ground in a hammer mill, resulting from different grinding degrees (0.97 mm, 1.11 mm, 1.35 mm, 1.51 mm, 1.69 mm, and 1.75 mm), which were stored for 15, 30, 60, 120, and 240 days. Data were analyzed as repeated measures using the MIXED procedure. When effects of interaction between factors were identified, data were analyzed as polynomial contrasts. Ruminal in situ DM disappearance was modeled across different storage lengths using a non-linear regression model. Prolamin was higher in 1.69 mm and 1.51 mm silages at 15 and 30 days of storage (P < 0.05). Also was observed a decrease in prolamin at 240 days of storage (P < 0.01). The pH of silages was lower after 60 days of storage (P < 0.01), a reduction which is linked to the smaller particle size in 1.11 mm and 1.75 mm silages (P < 0.01). No interaction effects were identified between storage length and DM loss. A greater loss occurred in 1.69 and 1.75 mm silages at 15, 30, and 240 days. At 15 and 60 days, a quadratic behavior was observed, varying according to the increase in particle size. Acetic acid, ethyl lactate, and 1,2 propanediol concentrations increased with storage length (P < 0.01). Lactic acid concentration was affected at 240 days, exhibiting a quadratic behavior according to particle size. The growth pattern of LAB exhibited a quadratic behavior as the mean RCGS particle size increased. The aerobic stability of silages increased after 60 days of storage (P < 0.01), and an interaction effect was found in relation to particle size. According to the Broken-line linear-linear model, maximum disappearance increments were observed at 36, 38, 39, 50, 54, and 46 days of storage for silages with particles measuring 0.97 mm, 1.11 mm, 1.35 mm, 1.51 mm, 1.69 mm, and 1.75 mm, respectively. All silages exhibited an adequate fermentation, and the minimum storage length depended on the particle size of RCGS ground in a hammer mill.