Improving rumen ecology and microbial population by dried rumen digesta in beef cattle

Estimating Microbial Protein Synthesis in the Rumen-Can 'Omics' Methods Provide New Insights into a Long-Standing Question?

Rumen microbial protein synthesis (MPS) provides at least half of the amino acids for the synthesis of milk and meat protein in ruminants. As such, it is fundamental to global food protein security. Estimating microbial protein is central to diet formulation, maximising nitrogen (N)-use efficiency and reducing N losses to the environment. Whilst factors influencing MPS are well established in vitro, techniques for in vivo estimates, including older techniques with cannulated animals and the more recent technique based on urinary purine derivative (UPD) excretion, are subject to large experimental errors. Consequently, models of MPS used in protein rationing are imprecise, resulting in wasted feed protein and unnecessary N losses to the environment. Newer 'omics' techniques are used to characterise microbial communities, their genes and resultant proteins and metabolites. An analysis of microbial communities and genes has recently been used successfully to model complex rumen-related traits, including feed conversion efficiency and methane emissions. Since microbial proteins are more directly related to microbial genes, we expect a strong relationship between rumen metataxonomics/metagenomics and MPS. The main aims of this review are to gauge the understanding of factors affecting MPS, including the use of the UPD technique, and explore whether omics-focused studies could improve the predictability of MPS, with a focus on beef cattle.

Effect of feeding Pleurotus pulmonarius-treated empty fruit bunch on nutrient digestibility and milk fatty acid profiles in goats

This study aimed to evaluate the effect of feeding P. pulmonarius-treated empty fruit bunch (FTEFB) on the nutrient intakes, digestibility, milk yield and milk profiles of lactating Saanen goats. A total of nine lactating Saanen goats were used in an incomplete cross-over experimental design. The balanced dietary treatments contain different replacement levels of Napier grass with FTEFB at 0% (0-FT), 25% (25-FT) and 50% (50-FT). The FTEFB contained crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL) at 4.10, 94.6, 70.8 and 19.4% DM, respectively. The replacement of FTEFB in 25-FT did not alter dry matter, NDF, hemicellulose, ADL, ether extract and gross energy intakes when compared to the control fed group (0-FT). The ADF and cellulose intake was higher in 25-FT than in the others (P < 0.001). The digestibility of hemicellulose, cellulose and ADL were not changed in 25-FT compared to the control group (P < 0.05) whereas when 50% FTEFB was incorporated to the diet, intermediate digestibility was decreased significantly (P < 0.05). Milk yield and protein content did not differ between the goat received 25-FT and the control group (P > 0.05). There are no differences in milk fatty profiles between dietary treatments (P > 0.05), except for OCFA. Goat fed with 25-FT had the lowest OCFA (P < 0.01) and significantly reduced the lauric acid concentration (P < 0 .05) when compared to the control group. Thus, replacement of NG in 25-FT does not adversely affect nutrient intake, fibre digestibility (cellulose and hemicellulose), milk yield, milk composition and milk fatty acid profiles. Overall, FTEFB may have potential to be used in the dairy goat diet as a roughage source to replace Napier grass.

The Effect of Indigo (Indigofera tinctoria L.) Waste on Growth Performance, Digestibility, Rumen Fermentation, Hematology and Immune Response in Growing Beef Cattle

This experiment was conducted to assess the effect of indigo waste on the feed intake, digestibility, rumen fermentation, hematology, immune response and growth performance in growing beef cattle. Twenty crossbred beef cattle with an initial body weight (BW) of 145 ± 11 kg were fed four levels of indigo waste for 90 days in a trial. Additions of indigo waste at 0%, 10%, 20% and 30% in a concentrate diet using a completely randomized design (CRD). Cattle were fed concentrate at 1.8% BW, with rice straw fed ad libitum. The concentrate intake decreased linearly (p = 0.01) with the addition of indigo waste. The supplementation with indigo waste reduced dry matter (DM) and organic matter (OM) digestibility cubically (p = 0.03 and p = 0.02, respectively), while increasing neutral detergent fiber (NDF) digestibility cubically (p = 0.02). The final BW of beef cattle decreased linearly (p = 0.03) with the addition of indigo waste. The inclusion of indigo waste decreased the average daily gain (ADG) and gain-to-feed ratio (G:F) linearly (p < 0.01) from 0 to 90 days. The nutrient digestibility, ADG and G:F of beef cattle fed 10% indigo waste in the diet was similar when compared with the control (0% indigo waste). The ruminal pH, ammonia-nitrogen (NH3-N) and total volatile fatty acid (VFA) concentrations were similar among treatments (p > 0.05). The proportion of acetate increased linearly (p < 0.01) but propionate decreased linearly (p < 0.01), resulting in an increase in the acetate to propionate ratio (p < 0.01) when cattle were fed with indigo waste supplementation. Increasing indigo waste levels did not influence blood urea nitrogen (BUN) levels, hematological parameters or immune responses (IgA, IgM and IgG) (p > 0.05). In conclusion, the inclusion of indigo waste at 10% in a concentrate diet did not have a negative effect on feed intake, nutrient digestibility, rumen fermentation, hematology, immune function or growth performance in growing beef cattle.

Effect of Sulfur and Urea Fortification of Fresh Cassava Root in Fermented Total Mixed Ration on the Improvement Milk Quality of Tropical Lactating Cows

The aim of the present research was to determine the influence of sulfur and urea combined with fresh cassava root in fermented total mixed ration (FTMR) on digestibility, fermentation in the rumen, blood metabolite, milk yield, and milk quality in tropical lactating dairy cows. Four mid-lactation Thai Holstein-Friesian crossbred cows were studied. Pre-experiment milk yield was 12.7 ± 0.30 kg/day, and the body weight was 495 ± 40.0 kg. Animals were evaluated in a 2 × 2 factorial in a 4 × 4 Latin square design to receive diets followed by: factor A, which was a dose of sulfur inclusion at 1.0% and 2.0%, and factor B, which was level of urea inclusion at 1.25% and 2.5% DM in FTMR. The hydrogen cyanide (HCN) concentrations reduced 99.3% to 99.4% compared with fresh cassava root when FTMR was supplemented with 1.0% and 2.0% sulfur, respectively. Intake of crude protein was increased based on urea level addition (p < 0.05). Blood thiocyanate concentration was increased by 21.6% when sulfur was supplemented at 2.0% compared to 1.0% (p < 0.05). There was no difference in protozoal concentration, whereas bacterial populations at 4 h after feeding were significantly greater by 6.1% with the FTMR supplemented with 2.0% sulfur and 2.5% urea (p < 0.01). Allantoin concentrations, excretion, absorption, and microbial crude protein showed significant interactions between sulfur levels and urea levels in cows fed diets supplemented with 2.0% sulfur and 2.5% urea (p < 0.05). The molar ratios of the volatile fatty acid (VFA) profile were affected by dietary FTMR (p < 0.01). Furthermore, propionic acid increased by 4.6% when diets were supplemented by 2.5% sulfur (p < 0.01). Milk fat and total solids increased when feed was supplemented with 2.0% sulfur and 2.5% urea (p < 0.05). The diets supplemented with 2.0% sulfur levels resulted in greater concentrations of milk thiocyanate (p < 0.05). The somatic cell count was significantly reduced throughout the experiment with increasing sulfur supplementation (p < 0.05). Animals fed diets supplemented with 2.0% sulfur exhibited a decreased somatic cell count by 18.3% compared with those fed diets supplemented with 1.0% sulfur. Thus, inclusion of 2.0% sulfur with 2.5% urea in FTMR containing fresh cassava root improved digestibility, ruminal fermentation, microbial crude protein synthesis, and milk qualities in dairy cows.

Improving Nutritive Value of Purple Field Corn Residue and Rice Straw by Culturing with White-Rot Fungi

It was hypothesized that white-rot fungus fermented with rice straw and purple field corn improves nutrient utilization via enhanced digestibility and lowers methane (CH₄) production due to the effects of the lovastatin compound. The aim of the current experiment was to investigate the effect of inoculation of two fungi belonging to white-rot fungus type on feed value and ruminal fermentation characteristic. The experiment was carried out according to a completely randomized 3 × 3 factorial design: three roughage sources (rice straw, purple corn stover, and purple corn field cob) for three inoculation methods (untreated, P. ostreatus treated, and V. volvacea treated). The two fungi increased concentration of lovastatin when compared to the untreated, and P. ostreatus had higher lovastatin production potential than V. volvacea (p < 0.05). The yield of lovastatin was obtained from rice straw fermentation with P. ostreatus. The monomeric anthocyanin content (MAC) in untreated purple field corn cobs was higher than in the fermentation groups. Ruminal fermentation gas production from soluble fractions ranged from −2.47 to 1.14 and differed among the treatments (p < 0.01). In comparison to all treatments, the gas production rate for the insoluble fraction was significantly highest (p < 0.01) in treatment alone, in which purple field corn stover was fermented with P. ostreatus and V. volvacea. There was significant interaction in in vitro dry matter digestibility at 12 h of incubation. Purple field corn cob had a higher significant effect on in vitro DM digestibility at 12 and 24 h after incubation when compared to that of other groups. Moreover, current research has found that roughage fermented with P. ostreatus and V. volvacea increased in vitro DM digestibility at 24 h after incubation. Fermenting roughage with fungi did not affect rumen pH, which ranged from 6.60 to 6.91 (p > 0.05), while P. ostreatus resulted in increased levels of ruminal ammonia-nitrogen concentrations. Propionic acid increased in all roughages fermented with P. ostreatus or V. volvacea after 8 h of ruminal fermentation testing. The two fungi fermented as substrate treatments had significantly lower (p < 0.05) CH₄ production. Based on the improved rumen DM digestibility and reduced CH₄ production, P. ostreatus and V. volvacea could be utilized for enhancing feeding efficiency of roughage.

Potential use of rumen digesta as ruminant diet-a review

This review paper is aimed at presenting and discussing the effects of rumen digesta (RD) as an alternative protein source on nutrient utilization, rumen fermentation characteristics, growth performances, and milk production in ruminants. RD is a by-product of abattoir; it is a partially digested feed that mainly originates from rumen of ruminants. RD consisted of 13.5-46.1% crude protein and some essential nutrients (microbial cells, amino acids, minerals, and volatile fatty acids [VFAs]), which beneficially affect the ruminant production. Recent studies have shown that transfer of RD from buffalo to cattle improved nutrient digestibility. Ensiling RD with agro-industrial by-products improved the nutritional value of agro-industrial by-products, such as by improving protein contents and increasing their digestibility. In addition, dried RD could enhance ruminal fermentation, diet utilization, and rumen microorganisms in in vitro, beef cattle and buffalo, which has no adverse effect on production performance. Therefore, utilization of RD is suggested because it improves nutrient utilization, reduces feed costs, and controls waste disposal to the environment.

Effects of Sulfur Levels in Fermented Total Mixed Ration Containing Fresh Cassava Root on Feed Utilization, Rumen Characteristics, Microbial Protein Synthesis, and Blood Metabolites in Thai Native Beef Cattle

Simple Summary

Feeding of fresh cassava root to animals is restricted because it contains hydrocyanic acid at a high level, which is the origin for poisoning. High levels of hydrocyanic acid from fresh cassava root could be detoxified by sulfur addition to become nontoxic to cattle. The addition of 2% sulfur in a fermented total mixed ration containing fresh cassava root and ensiling for 7 days could improve dry matter digestibility, efficiency of microbial protein synthesis, and concentrations of total volatile fatty acid, propionic acid, and blood thiocyanate.

Abstract

The influence of sulfur included in fermented total mixed ration (FTMR) containing fresh cassava root on rumen characteristics, microbial protein synthesis, and blood metabolites in cattle was evaluated. Four Thai native beef cattle were randomly assigned according to a 2 × 2 factorial in a 4 × 4 Latin square design, and dietary treatments were as follows: factor A included a level of sulfur at 1% and 2% in total mixed ration, and factor B featured ensiling times at zero and 7 days. Digestibility of dry matter was increased when FTMR was supplemented with 2% sulfur. Blood thiocyanate increased by 69.5% when ensiling time was 7 days compared to no ensiling (p < 0.01). Bacterial populations were significantly different in the FTMR containing sulfur at 2% and 7 days of ensiling. Furthermore, microbial crude protein and efficiency of microbial protein synthesis were higher in the FTMR containing 2% sulfur and 7 days of ensiling (p < 0.01). Thus, high levels of hydrocyanic acid from fresh cassava root could be detoxified by a sulfur addition with an ensiling process to become nontoxic to cattle.

Improving the nutritive value of cassava bioethanol waste using fermented yeast as a partial replacement of protein source in dairy calf ration

The aim of this work was to evaluate the influence of yeast (Saccharomyces cerevisiae)-fermented cassava bioethanol waste (YECAW) on feed utilization, ruminal fermentation, and microbial population in dairy calves fed a concentrate diet at 1% body weight (BW). Four male Holstein Friesian crossbred calves with an initial BW of 109 ± 6.23 kg were used in this research. The experimental design was a 4 × 4 Latin squared design and the dietary treatments were four levels of YECAW supplementation at 0%, 5%, 10%, and 20% concentrate mixture. The YECAW product contained CP at 25.1% dry matter (DM) and NDF and ADF at 65.2 and 40.6% DM, respectively. Inclusion of YECAW did not alter feed intake of rice straw, total intake, nutrient intake, and digestion coefficients (P > 0.05). Ruminal pH and temperature, ruminal ammonia-nitrogen, and blood urea-nitrogen (BUN) were not significant by YECAW levels supplementation (P > 0.05). Increasing YECAW levels did not adversely affect the population of bacteria, protozoa, and fungi and values ranged from 6.5 to 7.0 × 10¹², 3.2 to 4.0 × 10⁵, and 6.9 to 7.4 × 10³ cells/ml, respectively (P > 0.05). Feeding of YECAW to dairy calves did not affect the total VFA, acetic acid (C2), propionic acid (C3), or butyric acid (C4) proportion (P > 0.05) which ranged from 102.6 to104.6 mmol/l, 70.7 to 72.0, 17.8 to 20.2, and 9.1 to 10.3 mol/ 100 mol, respectively. Therefore, feeding of YECAW is recommended because no adversely affect the utilization of feed and rumen characteristics and might be alternative protein source for ruminants.

Effect of beta-glucan supplementation on feed intake, digestibility of nutrients and ruminal fermentation in Thai native beef cattle

This study was conducted to evaluate the effect of ß-glucan on feed intake, digestibility of nutrients and ruminal fermentation in Thai native beef cattle that were fed low-quality roughage. Four, Thai native beef cattle with initial body weight (BW) of 100 ± 20.0 kg were randomly assigned according to a 4 × 4 Latin square design to receive four treatment by ß-glucan at 0, 1.6, 3.1 and 4.7 g/day respectively. Supplementation of ß-glucan at 0-4.7 g in cattle did not affect the intake of DM, OM, CP, NDF or ADF. However, supplementation with ß-glucan significantly improved rice straw intake (g/kg BW^0.75 ), compared to the nonsupplemented group (p < 0.05), so rice straw intake was higher than in the group without ß-glucan supplementation. In addition, total feed intake increased with the higher level of ß-glucan supplementation. The estimated energy intake was not altered by ß-glucan supplementation (p > 0.05). The experimental diet had no effect (p > 0.05) on the apparent digestibility of DM, OM, NDF or ADF. However, the digestibility of CP was significantly different among treatment and supplementation at 4.7 g/day ß-glucan which was the highest level (63.2%) among all diets. ß-glucan supplementation did not affect rumen pH, temperature or ruminal NH₃ -N concentration. In addition, blood urea-N levels were similar among experimental groups. The population of protozoa at 4 hr post-feeding increased along with ß-glucan supplementation and was highest at 4.7 g of ß-glucan. Based on this experiment, it could be concluded that supplementation of ß-glucan at 4.7 g improved rice straw intake, as well as total intake and digestibility of CP in Thai native beef cattle.

Studies on bacterial community composition are affected by the time and storage method of the rumen content

The objective of this study was to investigate three storage methods and four storage times for rumen sampling in terms of quality and yield of extracted metagenomic DNA as well as the composition of the rumen bacterial community. One Nellore steer fitted with a ruminal silicone-type cannula was used as a donor of ruminal contents. The experiment comprised 11 experimental groups: pellet control (PC), lyophilized control (LC), P-20: pellet stored frozen at -20°C for a period of 3, 6, and 12 months, P-80: pellet stored frozen at -80°C for a period of 3, 6, and 12 months, and L-20: lyophilized sample stored frozen at -20°C for a period of 3, 6, and 12 months. Metagenomic DNA concentrations were measured spectrophotometrically and fluorometrically and ion torrent sequencing was used to assess the bacterial community composition. The L-20 method could not maintain the yield of DNA during storage. In addition, the P-80 group showed a greater yield of metagenomic DNA than the other groups after 6 months of storage. Rumen samples stored as pellets (P-20 and P-80) resulted in lower richness Chao 1, ACE, and Shannon Wiener indices when compared to PC, while LC and PC were only different in richness ACE. The storage method and storage time influenced the proportions of 14 of 17 phyla identified by sequencing. In the P-20 group, the proportion of Cyanobacteria, Elusimicrobia, Fibrobacteres, Lentisphaerae, Proteobacteria, and Spirochaetes phyla identified was lower than 1%. In the P-80 group, there was an increase in the proportion of the Bacteroidetes phylum (p = 0.010); however, the proportion of Actinobacteria, Chloroflexi, SR1, Synergistetes, TM7, and WPS.2 phyla were unchanged compared to the PC group (p > 0.05). The class Clostridium was the most abundant in all stored groups and increased in its proportion, especially in the L-20 group. The rumen sample storage time significantly reduced the yield of metagenomic DNA extracted. Therefore, the storage method can influence the abundance of phyla, classes, and bacterial families studied in rumen samples and affect the richness and diversity index.

Effect of feeding cassava bioethanol waste on nutrient intake, digestibility, and rumen fermentation in growing goats

This experiment was conducted to investigate the effects of various levels of cassava bioethanol waste (CBW) on nutrient intake, digestibility, rumen fermentation, and blood metabolites in growing goats. Twelve crossbred, male (Thai Native × Anglo Nubian) growing goats with initial body weight (BW) of 20±3 kg were randomly assigned according to a completely randomized design (CRD). The dietary treatments were total mixed ration (TMR) containing various levels of CBW at 0, 10, and 20 % dry matter (DM). CBW contained crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) at 11, 69, 47, and 23 % DM, respectively. The TMR diets were offered ad libitum and contained CP at 15 % DM. Inclusion of CBW at 10 % DM in TMR did not alter feed intake (g DM and g/kg BW(0.75)) and CP intake when compared to the control fed group (0 % CBW). Total OM intake was lower in the 20 % CBW group than in the others (P < 0.01). The digestibility coefficients of DM, OM, CP, and NDF were not changed for the TMR including 10 % CBW compared to the control group (P > 0.05) whereas when 20 % CBW was incorporated to diet, intermediate digestibility coefficients were decreased. Average ruminal pH values ranged from 6-7. Rumen NH3-N and PUN concentration at 0, 3, and 6 h post-feeding were not significantly different among treatments (P > 0.05). Thus, inclusion of 10 % CBW in TMR diets does not adversely affect nutrient intake, digestibility, rumen fermentation, and blood metabolite in fattening goats, and CBW may be effectively used as an alternative roughage source in the diets of goats.