Effects of defaunation and various nitrogen supplementation regimens on microbial numbers and activity in the rumen of sheep (original) (raw)
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Journal of Animal Science, 2009
Six ruminally and duodenally cannulated sheep were used in a partially replicated 4 × 4 Latin square to evaluate the effects of 4 diets on microbial synthesis, microbial populations, and ruminal digestion. The experimental diets had forage to concentrate ratios (F:C; DM basis) of 70:30 (HF) or 30:70 (HC) with alfalfa hay (A) or grass hay (G) as forage and were designated as HFA, HCA, HFG, and HCG. The concentrate was based on barley, gluten feed, wheat middlings, soybean meal, palmkern meal, wheat, corn, and mineral-vitamin premix in the proportions of 22, 20, 20, 13, 12, 5, 5, and 3%, respectively (as-is basis). Sheep were fed the diets at a daily rate of 56 g/kg of BW 0.75 to minimize feed selection. High-concentrate diets resulted in greater (P < 0.001) total tract apparent OM digestibility compared with HF diets, but no differences were detected in NDF digestibility. Ruminal digestibility of OM, NDF, and ADF was decreased by increasing the proportion of concentrate, but no differences between forages were detected. Compared with sheep fed HF diets, sheep receiving HC diets had less ruminal pH values and acetate proportions, but greater butyrate proportions. No differences among diets were detected in numbers of cellulolytic bacteria, but protozoa numbers were less (P = 0.004) and total bacteria numbers tended (P = 0.08) to be less for HC diets. Carboxymethylcellulase, xylanase, and amylase activities were greater for HC compared with HF diets, with A diets showing greater (P = 0.008) carboxymethylcellulase activities than G diets. Retained N ranged from 28.7 to 37.9% of N intake and was not affected by F:C (P = 0.62) or the type of forage (P = 0.31). Microbial N synthesis and its efficiency was greater (P < 0.001) for HC diets compared with HF diets. The results indicate that concentrates with low cereal content can be included in the diet of sheep up to 70% of the diet without detrimental effects on ruminal activity, microbial synthesis efficiency, and N losses.
Journal of Animal Science, 2009
Six ruminally and duodenally cannulated sheep were used in a partially replicated 4 × 4 Latin square to evaluate the effects of 4 diets on microbial synthesis, microbial populations, and ruminal digestion. The experimental diets had forage to concentrate ratios (F:C; DM basis) of 70:30 (HF) or 30:70 (HC) with alfalfa hay (A) or grass hay (G) as forage and were designated as HFA, HCA, HFG, and HCG. The concentrate was based on barley, gluten feed, wheat middlings, soybean meal, palmkern meal, wheat, corn, and mineral-vitamin premix in the proportions of 22, 20, 20, 13, 12, 5, 5, and 3%, respectively (as-is basis). Sheep were fed the diets at a daily rate of 56 g/kg of BW 0.75 to minimize feed selection. High-concentrate diets resulted in greater (P < 0.001) total tract apparent OM digestibility compared with HF diets, but no differences were detected in NDF digestibility. Ruminal digestibility of OM, NDF, and ADF was decreased by increasing the proportion of concentrate, but no differences between forages were detected. Compared with sheep fed HF diets, sheep receiving HC diets had less ruminal pH values and acetate proportions, but greater butyrate proportions. No differences among diets were detected in numbers of cellulolytic bacteria, but protozoa numbers were less (P = 0.004) and total bacteria numbers tended (P = 0.08) to be less for HC diets. Carboxymethylcellulase, xylanase, and amylase activities were greater for HC compared with HF diets, with A diets showing greater (P = 0.008) carboxymethylcellulase activities than G diets. Retained N ranged from 28.7 to 37.9% of N intake and was not affected by F:C (P = 0.62) or the type of forage (P = 0.31). Microbial N synthesis and its efficiency was greater (P < 0.001) for HC diets compared with HF diets. The results indicate that concentrates with low cereal content can be included in the diet of sheep up to 70% of the diet without detrimental effects on ruminal activity, microbial synthesis efficiency, and N losses.
Journal of Agricultural Science, 2014
This experiment was undertaken to evaluate the potential impacts of supplementing two direct-fed microbial (DFM) products, namely Bactozyme and Ru-max, to the diet of 12 male Barki sheep (live body weight 46.6 ± 2.9 kg) on dry matter intake (DMI), apparent total tract digestibility of nutrients, nitrogen balance and rumen fermentation characteristics. The Bactozyme or Ru-max were supplemented at a rate of 1.0 g/head/day, mixed with the concentrate mixture. Animals were randomly allocated into 3 equal groups (n=4) and were subjected to the digestibility trails. The results showed that the inclusion of either products of DFM had no positive impact on DMI, but non-significantly improved the apparent total tract digestibility of dry matter (DM), organic matter (OM) and crude protein (CP). However, the Bactozyme addition increased (P<0.05) the apparent total tract digestibility of neutral detergent fiber (NDF) and acid detergent fiber (ADF). The enhancement of the apparent total tract digestibility of cell wall was not significant for the two of DFM products and a non-significant improvement in cell wall digestion due to the Ru-max supplementation over the control group was found. The DFM products had positive impacts on the average of total digestible nutrients (TDN) and digestible crude protein (DCP) but non significant in comparison with the untreated animals. In addition, the nitrogen balance was improved (P>0.05) by 8 and 13% due to Ru-max and Bactozyme supplementation, respectively in comparison with the control group. The results also revealed that inclusion of DFM products had no impacts on rumen pH 3.0 and 6.0 h after feeding but Bactozyme reduced (P<0.05) the rumen pH 1.0 h after feeding compared to the control group. The inclusion of Bactozyme and Ru-max increased (P>0.05) the NH 3-N concentration in the rumen at 1.0 and 3.0 h after feeding but the Bactozyme decreased (P<0.05) the NH 3-N concentration and increased the volatile fatty acids (VFA) at 6.0 h after feeding compared to the control group. Overall, results indicated that the two DFM products had positive impacts on cell wall digestibility, which in turn improves metabolic energy supply and nutrients utilization in ruminants as well.
IOP Conference Series: Earth and Environmental Science, 2019
Concentrate-forage ratio may affect microbial nitrogen supply, thus it can be considered as one of feeding strategies in ruminant. This study evaluated the effect of different concentrate-forage ratio on rumen microbial nitrogen supply in Batur sheep. Twelve male Batur sheep aged 10-12 months were given three experimental diets in a one-way design using 14 d adaptation and 7 d collection periods. Experimental diets were concentrate (wheat pollard) and forage (Pennisetum purpuroides) offered with ratio of 20:80, 30:70, and 40:60 (w/w, DM basis). Total urine were collected for 24 h during collection period. Samples were analysed for allantoin, uric acid, xanthine-hypoxanthine, and purine derivatives. Feed and feed refusal were analysed for dry matter and organic matter. Concentrate-forage ratio tended to influence allantoin, xanthine-hypoxanthine, and purine derivatives excretions, as well as absorbed purine and rumen microbial protein synthesis. Feeding concentrate up to 40% signific...
Animal Feed Science and Technology, 2011
Studies were conducted to determine the rumen degradable nitrogen (RDN) requirement levels for optimum microbial protein synthesis and nutrient utilization in Nellore rams fed on finger millet straw (FMS) based diet. Thirty six Nellore sheep were randomly divided into four groups of nine animals each using the balanced completely randomized design. Animals in all the groups were fed finger millet straw as a basal roughage and groundnut cake (GNC) was offered daily in two equal halves in the morning (8.00 AM) and evening (4.00 PM) as RDN source. The animals in group I (GI) were fed with ad libitum FMS. Animals in group II, III and IV (GII, GIII, and IV) were offered GNC @ 12.4, 16.6, and 21.1 g RDN/kg digestible organic matter (DOM) along with FMS. The daily total dry matter (DM) and organic matter (OM) intakes linearly increased (P<0.05) with increasing level of RDN supplementation while there was no difference in total DM and OM intake/kg W 0.75 among different experimental groups. The digestibility coefficients of DM (P<0.001), OM (P<0.001), crude protein (CP) (P<0.001), ether extract (EE) (P<0.001), neutral detergent fibre (NDF) (P<0.01) and acid detergent fibre (ADF) (P<0.03) increased quadratically with increasing level of RDN supplementation from GI to GIV. The purine derivatives (PD) excretion, microbial purine absorption and microbial nitrogen supply (MNS g/day) linearly increased (P<0.001) as the level of RDN supplementation increased. There was no difference in nitrogen capture efficiency (NCE) and microbial nitrogen to total urinary nitrogen ratio (MN:UN) among the RDN supplemented groups. This study indicated that 12 g RDN/kg digestible organic matter intake (RDN g/kg DOMI) or 18 g RDN/kg OM apparently digested in the rumen (RDN g/kg DOMR) may be adequate for optimum microbial protein synthesis and digestibility of nutrients, there by improved plane of nutrition in sheep fed on finger millet straw based diet.
Effects of feed intake on composition of sheep rumen contents and their microbial population size
British Journal of Nutrition, 2003
The present study was conducted to determine the effect of feed intake on the composition of the rumen contents of sheep and on their bacterial densities. Whole rumen contents were sampled after a period of continuous inter-rumen infusion of 15 NH 3 from four rumencannulated wethers successively fed on a hay -concentrate diet (2:1, w/w on a DM basis) at two rates of feed intake: 40 and 80 g DM/kg body weight 0·75 . Total weight and chemical composition of rumen contents, as well as the distribution by size and chemical composition of particles, were determined. The populations of bacteria associated with the liquid (liquidassociated bacteria, LAB) and solid (solid-associated bacteria, SAB) fractions of rumen digesta and the distribution of SAB according to feed particle size were also examined. The greater feed intake caused an increase in the mass of the rumen contents, while its chemical composition did not change, except for a higher content of organic matter (P¼0·023). The distribution of feed particles by size was similar at both levels of intake. The concentrations of neutral-and acid-detergent fibre in feed particles decreased and those of total, dietary, and microbial N increased, both with a quadratic response (P¼0·001), as particle size decreased. The proportion of LAB in the microbial biomass of rumen digesta reached only 8·0 %. This proportion and the density of LAB were unaffected by the level of feed intake, whereas an apparent reduction (10·4 %) occurred with the SAB biomass in whole rumen contents. A systematic, but not significant, reduction (mean value 11·9 %) in the level of microbial colonisation in the different particle fractions with the increase of feed intake was also observed.
RUMEN MICROBIAL GROWTH IN SHEEP FED THREE DISTINCT QUALITY HAYS
Tropical and Subtropical Agroecosystems
Forages usually fed to sheep in tropics have low values of crude protein (CP) content and/or low availability of protein. The aim of this work was to identify different profiles of microbial protein (MP) yield for sheep fed hays with distinct CP levels. Three hays (LUC - Lucerne, SIG - signalgrass and TIF - Tifton- 85), six animals (Santa Inês wethers fitted with rumen and duodenum cannulas) placed in a double Latin square were used to evaluate transit rates of microbial protein and in vivo microbial synthesis. In vitro microbial protein synthesis was evaluated in a complete factorial statistical design. The parameters studied were rumen pH and ammonia-N, microbial protein transit using 15N as marker and microbial protein synthesis by in vivo (purine derivatives urinary excretion) and in vitro (32P incorporation) techniques. Rumen pH values did not present significant differences for treatments (hays) and these values were in a level considered as satisfactory to good microbial deve...
Journal of the Science of Food and Agriculture, 2021
BACKGROUND: Meeting the energy and nitrogen (N) requirements of high-performing ruminants at the same time as avoiding digestive disturbances (i.e. rumen acidosis) is a key priority in ruminant nutrition. The present study evaluated the effect of a cereal ammoniation treatment, in which barley grains are combined with urea and enzymes that catalyze the conversion of urea to ammonia to optimize rumen function. Twelve rumen cannulated sheep were randomly divided into two groups and fed a diet containing 60% of ammoniated barley (AMM) or untreated barley supplemented with urea (CTL) to investigate the impact on rumen fermentation and feed utilization. RESULTS: AMM had higher total N content and effective rumen degradable N than untreated barely. AMM sheep had a consistently higher rumen pH throughout the day (6.31 versus 6.03) and tended to have a lower post-prandial ammonia peak and higher acetate molar proportion (+5.1%) than CTL sheep. The rumen environment in AMM sheep favored the colonization and utilization of agro-industrial by-products (i.e. orange pulp) by the rumen microbes leading to a higher feed degradability. AMM sheep also had higher total tract apparent N digestibility (+21.7%) and urinary excretion of purine derivatives (+34%), suggesting a higher N uptake and microbial protein synthesis than CTL sheep. CONCLUSION: The inclusion of AMM in the diet of ruminants represents a valid strategy for maintaining rumen pH within a physiological range and improving N utilization by the rumen microbes, which could have positive effects on the health and productivity of animals in intensive production systems. These findings warrant further studies under conventional farm conditions.
Advances in Biological Sciences Research
This experiment aimed to compare the rumen microbial nitrogen supply in male and female Garut Sheep. Six male and female Garut sheep were put in the metabolism cages, fed ad libitum with Pennisetum purpureum and bran pollard with a ratio 60 : 40. This study begins with an adaptation period of 14 days. Urine collection was carried out for seven days. Urine samples be measured for purine derivatives (PD), consisting of allantoin, uric acid ,and xanthine-hypoxanthine. During the collection period, samples of feed, uneaten feed, and feces were taken out for dry matter and organic matter analysis. The total urinary PD excretions data were used to estimate microbial nitrogen supply (EMNS) based on the equation postulated with modification in endogenous PD excretion for male and female Garut sheeps. Data obtained were analyzed using the Independent Student T-Test design. The results showed that urinary PD excretion in male Garut sheep was higher than in females (0.160 vs 0.127 mmol/W 0.75 /day). EMNS in male Garut sheep also tended to be higher than in females (1.14 vs 0.74 g N/day). In conclusion, the excretion of PD and EMNS in male Garut sheep tended to be higher than in females.
Frontiers in Microbiology, 2023
Background: This study examined the effects of substituting cottonseed meal (CSM) or rapeseed meal (RSM) for soybean meal (SBM) on Hu sheep performance, rumen fermentation, and bacterial composition. 51 four-month-old indigenous male Hu sheep with starting body weights of 22.51 ± 2.84 kg and similar origins were randomly assigned to three treatments; (1) non-fermented total mixed ration (TMR) with SBM (CK), (2) fermented TMR containing CSM (F-CSM group), and (3) fermented TMR containing RSM (F-RSM group). Results: The three groups' intake of dry matter differed significantly (p < 0.05). In terms of average daily gain, the F-RSM group outperformed the CK and F-CSM groups (p < 0.05). The pH of the rumen was substantially lower in the CK group than in the F-CSM and F-RSM groups (p < 0.05), and the F-CSM group had greater amounts of volatile fatty acids (VFA) than the F-RSM and CK groups. In comparison to the CK group, the microbial crude protein yield was significantly higher in the F-CSM and F-RSM groups (p < 0.05). The F-CSM group significantly outperformed the F-RSM group of pepsin and cellulose enzyme activity (p < 0.05). The relative abundance of Bacteroidetes was greater in the CK and F-RSM groups compared to the F-CSM group (p < 0.05). In comparison to the other groups, Firmicutes were less abundant in the CK group (p < 0.05). Prevotella was present in a higher relative abundance in the F-CSM and F-RSM groups than in the CK group (p < 0.05). Prevotella was greater in relative abundance in the F-CSM and F-RSM groups than in the CK group (p < 0.05). The relative abundances of Veillonellaceae_UCG-001 and Lachnospiraceae_XPB1014 correlated with rumen butyric acid content and NH 3-N content (p < 0.05). Gene function prediction revealed that replacing SBM with F-CSM or F-RSM in the diet of Hu sheep can promote glycan biosynthesis and metabolism. Conclusion: The replacement of F-CSM and F-RSM for SBM has an influence on the richness and diversity of rumen bacteria at the phylum and genus levels. Replacement of SBM with F-CSM increased VFA yield and further promoted the performance of Hu sheep.