Rumen Fermentation End Products Research Articles

Combination effects of phytonutrient pellet and lemongrass (Cymbopogon citratus) powder on rumen fermentation efficiency and nutrient degradability using in vitro technique.

Phytonutrients (PTN) namely saponins (SP) and condensed tannins (CT) have been demonstrated to assess the effect of rumen fermentation and methane mitigation. Phytonutrient pellet containing mangosteen, rambutan, and banana flower (MARABAC) and lemongrass including PTN, hence these plant-phytonutrients supplementation could be an alternative plant with a positive effect on rumen fermentation. The aim of this experiment was to evaluate the effect of supplementation of MARABAC and lemongrass (Cymbopogon citratus) powder on in vitro fermentation modulation and the ability to mitigate methane production. The treatments were arranged according to a 3 × 3 Factorial arrangement in a completely randomized design. The two experimental factors consisted of MARABAC pellet levels (0%, 1%, and 2% of the total substrate) and lemongrass supplementation levels (0%, 1%, and 2% of the total substrate). The results of this study revealed that supplementation with MARABAC pellet and lemongrass powder significantly improved gas production kinetics (P < 0.01) and rumen fermentation end-products especially the propionate production (P < 0.01). While rumen methane production was subsequently reduced by both factors. Additionally, the in vitro dry matter degradability (IVDMD) and organic matter degradability (IVOMD) were greatly improved (P < 0.05) by the respective treatments. MARABAC pellet and lemongrass powder combination showed effective methane mitigation by enhancing rumen fermentation end-products especially the propionate concentration and both the IVDMD and IVOMD, while mitigated methane production. The combined level of both sources at 2% MARABAC pellet and 2% lemongrass powder of total substrates offered the best results. Therefore, MARABAC pellet and lemongrass powder supplementation could be used as an alternative source of phytonutrient in dietary ruminant.

Mitragyna speciosa Korth Leaf Pellet Supplementation on Feed Intake, Nutrient Digestibility, Rumen Fermentation, Microbial Protein Synthesis and Protozoal Population in Thai Native Beef Cattle.

This experiment evaluated the use of Mitragyna speciosa Korth leaf pellets (MSLP) on feed intake and nutrient digestibility in Thai native beef cattle. Four Thai native beef cattle steers were randomly assigned according to a 4 × 4 Latin square design to receive four dietary treatments. The treatments were as follows: control (no supplementation), MSLP supplement at 10 g/hd/d, MSLP supplement at 20 g/hd/d and MSLP supplement at 30 g/hd/d, respectively. All animals were fed a concentrate mixture at 0.5% body weight, while urea lime-treated rice straws were fed ad libitum. Findings revealed that feed intakes were increased by MSLP, which also significantly increased the digestibility of dry matter (DM), organic matter (OM) and neutral detergent fiber (NDF). Ruminal total volatile fatty acid (TVFA) concentration and propionate (C3) proportion were increased (p < 0.05) with MSLP supplementation, whereas ruminal ammonia-N (NH3-N), plasma urea nitrogen (PUN), acetate (C2), C2:C3 ratio and estimated methane (CH4) production decreased (p < 0.05). Total bacterial, Fibrobacter succinogenes and Ruminococus flavefaciens populations increased (p < 0.05) at high levels of MSLP supplementation, while protozoal populations and methanogenic archaea reduced (p < 0.05). Supplementation of MSLP also increased the efficiency of microbial nitrogen protein synthesis. Supplementing beef cattle with MSLP 10−30 g/hd/d significantly increased rumen fermentation end products and nutrient digestibility by mitigating protozoal populations and estimated CH4 production.

Chaya (Cnidoscolus aconitifolius, Mill. Johnston) pellet supplementation improved rumen fermentation, milk yield and milk composition of lactating dairy cows

• Chaya ( Cnidoscolus aconitifolius ) leaf pellet (CHYP) contains high level of crude protein and minerals. • CHYP supplementation enhanced nutrient digestibility, propionic acid (C 3 ) and balanced rumen pH and reduced calculated methane emission. • CHYP can improve milk yield and milk composition. Chaya ( Cnidoscolus aconitifolius , Mill. Johnston) is a fodder shrub that contains flavonoid compounds and uses as feeds, medicine and food, respectively. This study examined the effects of Chaya leaf pellet (CHYP) supplementation on nutrient digestibilities, feed intake, rumen fermentation, milk yield and milk compositions. Four lactating crossbred (75% Holstein-Friesian × 25% Thai native cows) dairy cows with average body weight (440 ± 10), milk production (12 ± 2 kg/h/d) and days- in- milk (126 ± 20) were randomly assigned to a 2 × 2 factorial arrangement in a 4 × 4 Latin square design. Two ratio of concentrate to milk yield, (1:1; CM1 and 1:2; CM2) and two CHYP levels at 0 and 6% of total dry matter intake (TDMI) were imposed. The results revealed that concentrate to milk yield ratio and CHYP supplementation had interactive effect ( P < 0.05) on nutrient intake except ADF, fat -corrected milk and total solids. Rumen pH was decreased ( P < 0.05) in cows receiving high concentrate, while the pH was in normal range for animals fed with CHYP. Ruminal NH 3 -N concentration was increased ( P < 0.05) by the 6% CHYP supplementation. The level of blood urea nitrogen (BUN) ( P < 0.05) was increased with the increase of ruminal NH 3 -N ( P < 0.01), and bacterial population, while the, protozoal counts were slightly reduced by the supplementation of CHYP. The CHYP supplementation significantly increased total VFA and propionate concentration, while decreased acetate to propionate ratio and estimated methane emission. In conclusion, concentrate to milk yield at 1:1 ratio and CHYP supplementation at 6% significantly modulated rumen fermentation end-products and milk composition in lactating dairy cows.

Feed Intake and Nutrient Digestibility, Rumen Fermentation Profiles, Milk Yield and Compositions of Lactating Dairy Cows Supplemented by Flemingia macrophylla Pellet

Feed intake and nutrient digestibility, rumen fermentation profiles, milk yield and compositions of lactating dairy cows fed with Flemingia macrophylla pellet (FMP) were evaluated. Four crossbred dairy cows in early lactation were randomly allocated into a 2×2 factorial arrangement in a 4×4 Latin square design (LSD). The first factor was protein level of concentrate mixtures consisted of two levels, i.e., 14% and 16%. The second factor was supplementation levels of FMP consisted of two levels, i.e., 0 and 150 g/cow/d. There were no interactions between the protein level of concentrate and FMP supplementation on feed intake and digestibility, rumen fermentation profiles, milk yield and composition of lactating dairy cows. The findings revealed that both factors significantly impacted feed intakes. They also significantly increased the digestibility of CP and neutral detergent fiber (NDF). Ruminal ammonia nitrogen and propionate (C3) concentrations were improved (p&lt;0.05), while rumen acetate (C2), the ratio of C2:C3, estimated methane (CH4) production, and protozoal counts were subsequently reduced (p&lt;0.05). Crude protein level and FMP supplementation additionally improved nitrogen absorption and utilization, as well as microbial nitrogen synthesis. Milk production was significantly increased by the FMP feeding. In conclusion, a concentrated mixture with 16% CP along with supplementation of FMP at a dose of 150 g/cow/d could significantly increase rumen fermentation end-products, microbial protein synthesis, mitigated rumen CH4 production, and milk production in lactating dairy cows fed with rice straw.

Sunnhemp (Crotalaria juncea, L.) silage can enrich rumen fermentation process, microbial protein synthesis, and nitrogen utilization efficiency in beef cattle crossbreds.

The objective of this experiment was to evaluate the effect of leguminous fodder silage on rumen fermentation, nutrient digestibility, and utilization in beef cattle crossbreds. Four cattle, with an average live weight of 280 ± 10 kg, were used in a 4 × 4 Latin square design with supplementation of various levels of sunnhemp silage (SHS). Sunnhemp silage was fed to cattle at 0, 1, 1.5, and 2 kg DM SHS/head/day. The DM, OM, and CP digestibilities were increased (P < 0.05), and the highest value was found by feeding 2 kg DM SHS/head/day. Total volatile fatty acids and individual volatile fatty acid (VFA) especially C3 were increased (P < 0.01), while C2 and C2:C3 ratios were decreased (P < 0.01) when SHS was supplemented. Nitrogen utilization efficiency and urinary purine derivatives were increased (P < 0.01) by the SHS supplementation. In conclusion, these data suggest that feeding SHS at 1.5 to 2 kg DM/ head/day can significantly increase rumen fermentation end-products, nitrogen utilization efficiency, and microbial protein synthesis. Sunnhemp silage can be practically processed and provided as a good roughage source for ruminants. Therefore, sunnhemp silage is recommended as a feeding intervention in the sub-tropical and tropical regions to support the sustainable livestock production.

Effect of Cyclotrichium niveum Essential Oil on Rumen Microbial Fermentation and in vitro Digestibility of Barley

The digestibility of feed in ruminants and the volatile fatty acids (VFA) resulting from digestion directly affect animal performance. It has long been studied on the use of essential oils as an alternative to antibiotics to ensure optimum conditions for the rumen environment. Cyclotrichium niveum (mountain mint) essential oil is rich in antimicrobial agents. In this study different doses (0, 50, 100 and 150 mg/L of culture fluid) of Cyclotrichium niveum essential oil was incubated 24 hours with barley in diluted ruminal fluid takes from fistulated cows fed with a 40:60 concentrate:forage diet in order to assess the effects on rumen microbial fermentation and in vitro true digestibility of barley. True digestibility of barley was determined in ANKOM Daisy Incubator. All doses of Cyclotrichium niveum significantly (P&amp;lt;0.001) decreased the in vitro dry matter (DM), organic matter (OM), neutral detergent fiber (NDF) digestibility of barley. Cyclotrichium niveum essential oil negatively affected end-products of rumen fermentation; the value of the measured rumen volatile fatty acids (VFA: acetate, propionate, butyrate, isobutyric acid, valerate and isovalerate) significantly decreased compared to the control group (P&amp;lt;0.001). Carbon dioxide and methane gases created as a result of incubation in rumen fluid were calculated using volatile fatty acid values formed in rumen fluid. The addition of Cyclotrichium niveum essential oil significantly reduces the CO2 in rumen fluid (P&amp;lt;0.001). Methane (CH4) gas from rumen fluid was significantly decreased in treatment groups compared the control group (P &amp;lt;0.001) While end-products of rumen fermentation parameters significantly decreased with all doses of Cyclotrichium niveum essential oil, rumen pH has increased (P&amp;lt;0.05). The results show that when the Cyclotrichium niveum essential oil incubated with barley significantly inhibited the rumen microbial activity and overall fermentation process of rumen.

PSIV-20 Evaluation of calf performance when cows grazing native rangeland are vaccinated for bovine viral diarrhea virus and infectious bovine rhinotracheitis using either a modified live or killed vaccine

Abstract Bovine viral diarrhea virus (BVDV) is a pathogen associated with gastrointestinal, respiratory, and reproductive diseases of cattle worldwide. Vaccination of cattle with antivirals have proven effective to reduce instances of BVDV. However, vaccination protocol adoption by producers and animal response to vaccination varies. The objective of this study was to determine if administration to the dam of a modified-live viral vaccine (MLV) or killed viral vaccine (KV) would impact the growth and rumen fermentation end products of the calf. The hypothesis for this study was that calves from dams vaccinated with MLV would have improved performance. Calves (n=20) born to dams that received either MLV or KV over the course of their lifetime, were housed on rangeland at the Corona Range and Livestock Research Center in Corona, NM. Cow ruminal contents were collected at birth. Both cow and calf ruminal contents were collected at 7, 35, 63, and 205 d of age. Cow body condition score did not differ between treatments (P &amp;gt; 0.05) (average KV = 4.3 + 0.8 and MLV = 4.3 + 0.8) at calving. Additionally, calf birth (P =0.66) weight and weaning weight (P &amp;gt; 0.05) did not differ between dam vaccine type. At days postpartum x vaccine type interaction was not observed for calf ruminal pH (P = 0.20) and volatile fatty acid concentrations (P &amp;gt; 0.28). However, calf ruminal pH increased with age (P &amp;lt; 0.0001). Butyrate concentrations were least at 7 days of age (P = 0.0069). Therefore, we reject our hypothesis; calves born from dams receiving MLV do not have improved performance when compared to KV counterparts. Results indicate birth weight, weaning weight, pre-weaned calves pH, and volatile fatty acid concentration, are not impacted by dam’s vaccination type. However, impacts on calf immunity have not been evaluated and require further research.

PSI-33 Evaluation of calf performance when cows grazing native rangeland are vaccinated for bovine viral diarrhea virus and infectious bovine rhinotracheitis using either a modified live or killed vaccine

Abstract Bovine viral diarrhea virus (BVDV) is a pathogen associated with gastrointestinal, respiratory, and reproductive diseases of cattle worldwide. Vaccination of cattle with antivirals have proven effective to reduce instances of BVDV. However, vaccination protocol adoption by producers and animal response to vaccination varies. The objective of this study was to determine if administration to the dam of a modified-live viral vaccine (MLV) or killed viral vaccine (KV) would impact the growth and rumen fermentation end products of the calf. The hypothesis for this study was that calves from dams vaccinated with MLV would have improved performance. Calves (n = 20) born to dams that received either MLV or KV over the course of their lifetime, were housed on rangeland at the Corona Range and Livestock Research Center in Corona, NM. Cow ruminal contents were collected at birth. Both cow and calf ruminal contents were collected at 7, 35, 63, and 205 d of age. Cow body condition score did not differ between treatments (P &amp;gt; 0.05) (average KV = 4.3 + 0.8 and MLV = 4.3 + 0.8) at calving. Additionally, calf birth (P =0.66) weight and weaning weight (P &amp;gt; 0.05) did not differ between dam vaccine type. At days postpartum x vaccine type interaction was not observed for calf ruminal pH (P = 0.20) and volatile fatty acid concentrations (P &amp;gt; 0.28). However, calf ruminal pH increased with age (P &amp;lt; 0.0001). Butyrate concentrations were least at 7 days of age (P = 0.0069). Therefore, we reject our hypothesis; calves born from dams receiving MLV do not have improved performance when compared to KV counterparts. Results indicate birth weight, weaning weight, pre-weaned calves pH, and volatile fatty acid concentration, are not impacted by dam’s vaccination type; however, impacts on calf immunity have not been evaluated and require further research.

Enhancing lactating dairy cow rumen fermentation and production with Flemingia silage containing phytonutrients

Level of protein and type of feed resources can greatly impact on ruminant production efficiency. This study was designed to determine the effect of protein level and Flemingia macrophylla silage (FMS) supplementation on rumen fermentation end-products, milk production and composition in lactating dairy cows. Four, multiparous lactating Holstein-crossbred cows (75% Holstein-Friesian and 25% Thai native breed) with 90 ± 10 days in milk, were randomly arranged in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement to receive four dietary treatments. Two protein levels of concentrate, 16 and 18% CP and level of FMS supplementation at 0 and 0.6 kg DM/cow/d. The experimental findings revealed that intake of concentrate and total feed intake were significantly enhanced with CP and FMS supplementation (P < 0.05). In addition, CP and FMS supplementation levels improved digestibilities of DM, OM, CP, NDF and ADF (P < 0.05). While, increasing level of protein and FMS supplementation ruminal ammonia nitrogen was increased while propionate, acetate, butyrate, acetate to propionate ratio, estimated methane production and protozoal population were decreased (P < 0.05). Level of protein FMS supplementation remarkably increased allantoin excretion, absorption, and efficiency of microbial nitrogen synthesis. Furthermore, milk yield especially milk fat corrected milk (FCM) were dramatically enhanced in cows fed with higher protein level and FMS supplementation. Based on this study, it could be concluded that FMS supplementation at 0.6 kg DM/cow/d when fed with concentrate mixture containing 18% CP showing interactive effect (P < 0.05) improved nutrient digestibilities, rumen fermentation efficiency, and milk production in lactating dairy cows.

Effects of Phytonutrients on Ruminal Fermentation, Digestibility, and Microorganisms in Swamp Buffaloes.

Simple SummaryFermentation in ruminants can influence greenhouse gas production, especially methane (CH4) production. Phytonutrients (PTN) and secondary metabolites (tannins, saponins) have antimicrobial activity which can be used for the inhibition of rumen methanogens and the reduction of methane emissions in ruminants. The aim of the present study was to investigate the influence of PTN containing both mangosteen peel powder and banana flower powder on feed consumption, nutrient digestibility, and rumen microorganisms in swamp buffaloes. The results suggest that supplementation of PTN can improve fiber digestibility, increase the proteolytic and cellulolytic bacteria, and alter rumen volatile fatty acids (VFAs), especially increased C3 and reduced methane production. This study shows that PTN containing either mangosteen peel powder (MSP) or banana flower powder (BFP) could be used as a rumen modifier. This experiment aimed to use dietary sources containing phytonutrients (PTN) such as mangosteen peel powder (MSP) and banana flower powder (BFP) as sources of phytonutrients. Four swamp buffalo bulls fitted with rumen fistulae were used as experimental animals. A digestion trial covering four periods was used according to a 4 × 4 Latin square design with four treatments: Treatment 1 (T1) = control (Cont), T2 = supplementation of PTN1 fed at 100 g/d, T3 = supplementation of PTN2 fed at 100 g/d, and T4 = supplementation of PTN3 fed at 100 g/d. The experiment was conducted for four periods; each period lasted for 21 days. All animals were fed a concentrate mixture at 0.5% body weight, while rice straw, water, and mineral blocks were fed ad libitum. The findings revealed significant increases in the digestibility of neutral detergent fiber (NDF) and acid detergent fiber (ADF), while no changes in dry matter feed consumption occurred due to PTN supplementation. Rumen fermentation end-products, such as total volatile fatty acids (TVFA), propionic acid (C3), and butyric acid (C4), were notably enhanced (p < 0.05) and there were the highest in PTN2 and PTN3, whilst acetic acid (C2) was significantly decreased with PTN supplementation groups. Furthermore, the rumen protozoal population was suppressed (p < 0.05), which resulted in decreased rumen methane production (p < 0.05), while the bacterial population was enhanced. Using PTN sources can improve rumen fermentation as well as mitigating rumen methane production.

Effect of increasing the proportion of chicory in forage-based diets on intake and digestion by sheep

There is a lot of evidence that chicory could be a highly palatable and nutritious source of forage for ruminants, well adapted to climate change and dry conditions in summer, thanks to its resistance to drought and high water content. This study aimed to describe the effect of incorporating chicory to ryegrass or to a ryegrass–white clover mixture on feeding behaviour, digestive parameters, nitrogen (N) balance and methane (CH4) emissions in sheep. In total, three swards of ryegrass, white clover and chicory were established and managed in a manner ensuring the forage use at a constant vegetative stage throughout the experiment. In all, four dietary treatments (pure ryegrass; binary mixture: 50% ryegrass–50% chicory; ternary mixture: 50% ryegrass–25% white clover–25% chicory; and pure chicory) were evaluated in a 4×4 replicated Latin square design with eight young castrated Texel sheep. Each experimental period consisted of an 8-day diet adaptation phase, followed by a 6-day measuring phase during which intake dynamics, chewing activity, digestibility, rumen liquid passage rate, fermentation end-products, N balance and CH4 emissions were determined. Data were analysed using a mixed model and orthogonal contrasts were used to detect the potential associative effects between ryegrass and chicory. The daily voluntary dry matter intake was lower for pure ryegrass than for diets containing chicory (P<0.001) and increased quadratically from 1.39 to 1.74 kg/day with increasing proportion of chicory. Huge positive quadratic effects (P<0.001) between ryegrass and chicory were detected on eating time and eating rate just after feeding indicating an increase of the motivation to eat with mixtures, whereas rumination activity decreased linearly with the proportion of chicory (P<0.001). The organic matter digestibility was similar among treatments (around 80%), but a strong positive quadratic P<0.001) effect was observed on liquid passage rate suggesting that chicory allowed fast particle breakdown in the rumen. Animals fed with the ryegrass–white clover–chicory mixture had the higher urinary N losses (P<0.001), whereas retained N per day or per g N intake was greater when the proportion of chicory was at least 50% (P<0.001) being ~40% greater than for the other treatments. The CH4 yield was lower with pure chicory than with the other treatments (P<0.001) for which emissions were similar. In conclusion, mixing ryegrass and chicory in equal proportions produces a synergy on voluntary intake and an improved N use efficiency likely due to complementarity in chemical composition, increased motivation to eat and faster ruminal particle breakdown.

349 Relationship between ruminal volatile fatty acids and microbial population with carcass and meat quality traits in beef steers.

Volatile fatty acids (VFAs), the end products of rumen fermentation, are the principal energy source for ruminants which potentially affect carcass yield and fat deposition in beef cattle. Rumen microbiota affects lipid metabolism in ruminants which might contribute to the variation in fat deposition. In this study, rumen fluid samples were collected from 204 beef steers raised under feedlot in Roy Berg Kinsella Research Ranch, University of Alberta. Individual VFA concentrations were measured using gas chromatography, and the bacterial and archaeal abundances were estimated by measuring total copy numbers of their respective 16S rRNA genes using qPCR. Animal phenotypic measures including body weight (BW), dry matter intake (DMI), average daily gain (ADG), hot carcass weight (HCW), age at slaughter (age), ribeye area (CREA), adipose fat thickness (AFAT), lean meat yield (LMY) and marbling score (MS) were collected. The relationships among microbiota, VFAs and carcass traits were evaluated using stepwise, backward linear regression with a significant level of 0.05. The HCW was positively correlated with BW and ADG and was negatively correlated with propionate. Negative correlations were identified between age and BW, RFI, acetate, propionate, and butyrate. CREA had positive correlations with BW and DMI, and negative correlations with acetate. AFAT was positively correlated with DMI, BW and propionate while, acetate and butyrate tentatively positively correlated (P < 0.1) with AFAT. The LMY was negatively correlated with BW, DMI, acetate, propionate and butyrate. Marbling score was positively correlated with DMI, acetate, propionate and butyrate. The relationship between rumen microbial abundance and the above carcass and meat quality-related traits were not detected in this study. Our preliminary results reveal that rumen VFAs may contribute to carcass and meat quality traits in beef cattle, suggesting the potential application to improving carcass and meat quality in beef steers through manipulating rumen VFA.

Strategic supplementation of cassava top silage to enhance rumen fermentation and milk production in lactating dairy cows in the tropics.

High-quality protein roughage is an important feed for productive ruminants. This study examined the effects of strategic feeding of lactating cows with cassava (Manihot esculenta) top silage (CTS) on rumen fermentation, feed intake, milk yield, and quality. Four early lactating crossbred dairy cows (75% Holstein-Friesian and 25% Thai) with body weight (BW) 410 ± 30kg and milk yield 12 ± 2kg/day were randomly allotted in a 4 × 4 Latin square design to four different supplementation levels of CTS namely, 0, 0.75, 1.50, and 2.25kg/day of dry matter (DM). Strategic supplementation of CTS significantly affected ruminal fermentation end-products, especially increased propionate production, decreased protozoal population and suppressed methane production (P < 0.05). Increasing the CTS supplementation level substantially enhanced milk yield and the 3.5% FCM from 12.7 to 14.0kg/day and from 14.6 to 17.2kg/day (P < 0.05) for non-supplemented group and for the 2.25kg/day supplemented group, respectively. We conclude that high-quality protein roughage significantly enhances rumen fermentation end-products, milk yield, and quality in dairy cows.

Morphological Identification of Rumen Protozoal Population in Domestic Ruminants of Chennai

Rumen is a complex ecosystem where feed consumed by ruminants is digested by the help of symbiotic microbes (bacteria, protozoa, and fungi) and the interaction between the host and ruminal microorganisms are diverse. This provides an advantage in the ability of ruminant digestion. End products of rumen fermentation are volatile fatty acids and the microbial biomass. The distribution of rumen microbes, their numbers, type, vary in the ruminants and is altered by the type of feed fed and the geographical location where the host is reared. A study was designed to investigate the rumen protozoal population present in domestic ruminants of Chennai, India by using new methods of staining, fixing and identification of different subfamilies and genera of protozoa. A total of 30 rumen fluid samples (10 cattle, 10 sheep, 10 goat) were collected. Rumen fluid was preserved with methyl green formalin sodium chlorate (MFS) stain. The body dimension and variation of characters such as location of ciliary areas, cell shape and size, location and size of skeletal plates and the number of protozoa were examined under optical microscope. Rumen protozoal counting of three different ruminant species revealed different mean values of which highest was recorded in cattle (7.009  106/ml rumen fluid) followed by goat (5.08  106/ml 08 rumen fluid) and sheep (4.996  106/ml rumen fluid). The analysis of rumen protozoal population in cattle, sheep and goats revealed predominance of the following genres of the protozoal family: Entodinium, Epidinium, and some subtypes of subfamily of Diplodiniinae. Keywords: Identification, rumen protozoa, ruminants Cite this Article Gogoi J, Rajamanickam K, Leela V. Morphological identification of rumen protozoal population in domestic ruminants of Chennai. Research & Reviews: Journal of Veterinary Science and Technology. 2018; 7(1): 12–15p.

Volatile fatty acids and methane production from browse species of Algerian arid and semi-arid areas

ABSTRACTThe objective of the study was to determine the in vitro rumen fermentation end-products of 10 browse species. Serum bottles containing 500 mg of substrate, 10 ml of sheep rumen fluid and 40 ml of buffered medium were incubated for 24 h. After incubation, pH, methane and volatile fatty acid (VFA) productions were recorded. There were differences among feedstuffs (p < .05) in pH and VFA production. Astragalus gombo resulted in the highest and Stipa tenacissima in the lowest VFA production. Gas production was highest for Medicago sativa and lowest for S. tenacissima. Methane production (ml/g DM incubated) varied greatly. The lowest methane production was for S. tenacissima and Arthrocnemum macrostachyum (11.4 and 11.5 ml/g DM, respectively) and the highest for M. sativa and A. gombo (25.8 and 22.7 ml/g DM, respectively). The differences among species shrank when methane was expressed per ml of total gas produced or per mol of VFA produced. This indicates that a lower methane production would be due to a low fermentability of the substrate incubated, rather than to a specific inhibitory effect on methanogenesis. Hence, the 10 browse species studied herein would show little potential for mitigating ruminal methane production.

Evidence of In Vivo Absorption of Lactate and Modulation of Short Chain Fatty Acid Absorption from the Reticulorumen of Non-Lactating Cattle Fed High Concentrate Diets.

Short-chain fatty acids (SCFAs) and lactate are endproducts of rumen fermentation and important energy sources for the host ruminant. Because their rapid accumulation results in ruminal acidosis, enhancement of the absorption of SCFA and lactate across reticuloruminal wall is instrumental in increasing energy supply and preventing ruminal acidosis in cattle. This study investigated whether the reticuloruminal absorption of SCFAs and lactate was altered by different strategies of high concentrate feeding. Eight rumen-cannulated, non-lactating Holstein cows were fed a forage-only diet (baseline) and then gradually adapted over 6 d to a 60% concentrate level. Thereafter, this concentrate-rich diet was fed for 4 wk either continuously (Con; n = 8) or interruptedly (Int; n = 8). Absorption of SCFAs and lactate was determined in vivo from the experimental buffer introduced into the washed reticulorumen. The buffer contained acetate, propionate, butyrate and lactate at a concentration of 60, 30, 10 and 5 mmol/L, respectively and Cr-EDTA as a marker for correcting ruminal water fluxes. The reticuloruminal absorption after 35 and 65 min of buffer incubation was measured at the baseline, after 1 wk of 60% concentrate feeding in the interrupted model (Int-1) and after 4 wk of concentrate feeding in both feeding models (Int-4 and Con-4). Data showed that the absorption rates of individual and total SCFAs during the first 35 min of incubation of Con-4 were highest (~1.7 times compared to baseline), while Int-1 and Int-4 were similar to respective baseline. Lactate was not absorbed during forage-only baseline and 1-wk concentrate feeding, but after 4-wk feeding of concentrates in both models. In conclusion, SCFAs absorption across the reticulorumen of non-lactating cattle was enhanced by the 4-wk continuous concentrate feeding, which seems to be more advantageous in terms of rumen acidosis prevention compared to the interrupted feeding model. The study provides evidence of lactate absorption across the reticulorumen of non-lactating cattle after both continuous and interrupted 4-wk concentrate feeding.

Sampling procedure for the measurement of dissolved hydrogen and volatile fatty acids in the rumen of dairy cows.

Dissolved hydrogen (dH) influences the pathways of VFA production and is a precursor of methane formation in the rumen. Measurements of dH in rumen fluid taken at the same time as measuring other rumen fermentation end products would improve our quantitative understanding of the role of dH as a controller of rumen fermentation. Sample collections though a rumen cannula and using oral stomach tubing were compared for measurements of dissolved gases and fermentation end products in the rumen fluid of 4 ruminally cannulated dairy cows fed a total mixed ration of corn silage and concentrate. Rumen fluid was collected at 0, 2.5, and 6 h after morning feeding through the cannula from cranial dorsal rumen, cranial ventral rumen, central rumen, caudal dorsal rumen, and caudal ventral rumen and in parallel by oral stomach tubing at 2 insertion depths of 180 cm (sampling the central rumen) and 200 cm (sampling the caudal dorsal rumen). The cranial dorsal rumen had the greatest pH and smallest VFA concentration among 5 sites sampled. Samples collected by oral stomach tubing had greater ( < 0.001) rumen pH and less ( < 0.001) dissolved methane (dCH) and lower VFA concentration than that collected through rumen cannula. The dH concentrations were positively correlated ( > 0.8) in rumen samples collected by the 2 sampling techniques, with a concordance correlation coefficient larger than 0.8 and scale shift being about 0.1 away from unity. The variations in the measurement of dH, dCH, pH, and VFA in samples collected by oral stomach tubing are most likely the result of saliva contamination. The time of sampling relative to feeding had significant influence ( < 0.01) on dissolved gases and fermentation end products, with the greatest concentrations of dH, dCH, and VFA measured 2.5 h after morning feeding. The dH was correlated positively ( > 0.58) with dCH and negatively ( < -0.65) with the estimated net H production relative to the amount of VFA produced. This indicated that greater dH enhanced rumen CH production and also led to fermentation pathways that produce less H, such as enhanced propionate and butyrate production. In summary, oral stomach tubing could be a feasible method to measure ruminal dH in intact animals, but caution should be taken to minimize saliva contamination. Measurements made using both techniques yield similar conclusions for the effects of dH on fermentation pathways and CH generation.

Dose-response effect of nitrate on hydrogen distribution between rumen fermentation end products: an in vitro approach

The objective of this work was to study the in vitro dose-response effect of nitrate (0, 1, 2, 4 and 6 mM) on metabolic hydrogen distribution between rumen fermentation end products. Three 48-h incubations were conducted using bovine rumen contents as an inoculum, and a mixture of hay and concentrate (50 : 50) as a substrate. Total gas production and composition (methane and hydrogen) were automatically analysed throughout the incubations. Volatile fatty acid and ammonium concentrations were analysed from samples taken after 48 h of incubation. Total gas production was decreased with the highest dose of nitrate (P = 0.002). Methane emissions linearly decreased as the nitrate dose increased (P = 0.005). Kinetics of methane emissions showed that metabolic hydrogen removal via nitrate reduction occurred mainly during the first 10 h of incubation. Gaseous hydrogen production was similar among treatments, despite higher hydrogen emissions for nitrate concentrations &gt;4 mM. Concentrations and proportions of volatile fatty acids were not affected by treatments. The proportion of unaccounted metabolic hydrogen was positive for all treatments, and tended to linearly increase as the nitrate dose increased. In this in vitro work, we confirmed that nitrate is an efficient methane-mitigating compound in the rumen. We also suggest that nitrate or its reduced forms have a direct inhibiting effect towards methanogens, as indicated by the release of gaseous hydrogen and the high efficiency of methane mitigation. However, high nitrate concentrations also decrease overall fermentation.

Digestion and ruminal fermentation of cocoa pod silage based ration enriched by gliricidia and calliandra leaves on goats

In term of availability, cacao pod is potential for ruminant feed. According to its nutrients content, cacao pod can be used as feed fiber source. Protein sources materials must be added when cacao pod was ensilaged due to low protein content of this material. The aim of this study was to investigate digestibility value and end products of rumen fermentation of goat fed grass or cacao pod based ration. Randomized block design and 20 heads of lambs (16.95±2.36 kg) to evaluated 5 type of rations: R (50% grass + 50% concentrate); S (50% cacao pod silage + 50% concentrate); SG (50% cacao pod-gliricidia silage + 50% concentrate); SK (50% cacao pod-calliandra silage + 50% concentrate) dan SC (50% cacao pod-mixture of gliricidia-calliandra silage + 50% concentrate). Feeding trial was conducted for over 15 weeks. Measurements were taken on feed digestibility and rumen-fermentation end-products after 3 weeks of treatments. Results shows that nutrients digestibility was different significantly among the groups of treatments (P<0.05). Digestibillity of organic matter, NDF and energy of R ration was those of higher significantly (P<0.05) than those of other groups. N-ammonia of rumen from goat feed R ration was higher (P<0.05) than other groups. Total VFA and each component were different among the groups (P<0.05), however the value was similar among the groups of cacao pod silage rations. It is concluded that cacao pod silaged based rations enriched by Gliricidia and Calliandra leaves did not produce similar digestibility value and end products of rumen fermentation with grass based ration.

Prolonged, moderate nutrient restriction in beef cattle results in persistently elevated circulating ghrelin concentrations1,2

Four ruminally cannulated steers (BW 581 +/- 12.8 kg) were used in a crossover design to determine the effects of prolonged, moderate nutrient restriction on plasma ghrelin concentrations and to establish the relationship of plasma ghrelin concentrations with hormones and metabolites indicative of nutritional status and end products of rumen fermentation. A high-grain diet was offered at 240% of the intake needed for BW maintenance (2.4xM) or 80% of the intake needed for BW maintenance (0.8xM). To standardize, all steers were acclimated to 2.4xM before initiation of the treatment periods. During period 1, 2 steers continued at 2.4xM, whereas intake for the remaining 2 steers was restricted to 0.8xM. On d 7, 14, and 21 after initiation of the restriction, serial blood samples were collected at 15-min intervals via indwelling jugular catheter and were assayed for ghrelin, GH, NEFA, insulin, and glucose concentrations. Rumen fluid was collected at hourly intervals for evaluation of pH and VFA concentrations. After period 1, steers were weighed, the treatments were switched between steer groups, and the intake amounts were recalculated. Intake of 2.4xM was established for previously restricted cattle, and period 2 was then conducted as described for period 1. Data were analyzed statistically as repeated measures in time, and stepwise regression was used to define the relationship of plasma ghrelin with hormones, metabolites, and end products of rumen fermentation. Throughout the 21-d treatment period, plasma ghrelin concentrations were elevated (P <or= 0.001) for steers offered the 0.8xM diet. Plasma GH and NEFA concentrations were increased (P <or= 0.001) and insulin concentrations were decreased (P <or= 0.001) for steers offered 0.8xM, indicating a catabolic state throughout the treatment period. Stepwise regression indicated that the fluctuation in plasma ghrelin was correlated weakly with hormones and metabolites indicative of nutritional status as well as end products of carbohydrate fermentation in the rumen. These data are consistent with the hypothesis that plasma ghrelin concentrations are elevated for cattle experiencing prolonged, moderate nutrient restriction that results in a catabolic state. Fluctuations in plasma ghrelin concentrations, however, have a weak relationship with hormones, metabolites, and end products of rumen fermentation.