Total Protozoa Count Research Articles

Effects of post-pyrolysis treated biochars on methane production, ruminal fermentation, and rumen microbiota of a silage-based diet in an artificial rumen system (RUSITEC)

This study investigated the effects of including biochars, which differed in post-pyrolysis treatment, on nutrient disappearance, total gas and methane (CH4) emissions, rumen fermentation, microbial protein synthesis and rumen microbiota in an artificial rumen system (RUSITEC) fed a barley silage-based diet. The basal diet contained (g/kg dry matter (DM) basis); 600 barley silage, 270 barley grain, 100 canola meal and 30 mineral/vitamin supplement. Three spruced-based biochars were treated post-pyrolysis with either zinc chloride, a hydrochloric acid/nitric acid mixture or sulfuric acid and each included at 20 g/kg of diet DM. Treatments were assigned to sixteen fermenters (n = 4/treatment) in two RUSITEC units in a randomized complete block design. The experiment was conducted over 15 d, with 8 d of adaptation and 7 d of sampling and data collection. Nutrient disappearance of DM, organic matter (OM), acid detergent fiber (ADF), nutrient detergent fiber (NDF) and starch were determined after 48 h of incubation from d 9–12, and microbial protein synthesis was measured from d 14−15. Data were analyzed using PROC MIXED in SAS, with fixed effects of treatment and day of sampling (repeated measure) and random effects of RUSITEC unit and fermenters. Biochar inclusion did not affect disappearance of DM (P = 0.49), OM (P = 0.60), CP (P = 0.47), NDF (P = 0.48), ADF (P = 0.11) or starch (P = 0.58). Moreover, biochar inclusion did not affect total gas production (P = 0.31) or CH4 produced expressed as mg/g of DM incubated (P = 0.74), and mg/g (P = 0.64), or mg/d (P = 0.70) of DM disappeared. Compared to the control, there was a tendency (P = 0.06) for reduced CH4 production with biochar inclusion when CH4 was expressed as percent of total gas produced. Biochar inclusion did not affect total VFA (P = 0.56) or NH3-N (P = 0.20) production. Microbial protein synthesis was not affected by biochar inclusion (P > 0.05). Total protozoa counts were also unaffected by biochar (P = 0.37) nor did it impact (P > 0.05) the alpha or beta diversity of bacterial populations. In conclusion, the biochars evaluated in this study appeared to have little to no impact on nutrient disappearance, total gas and CH4 production, rumen fermentation, and rumen microbiota in the RUSITEC system.

Comparison of Two Sampling Techniques for Evaluating Ruminal Fermentation and Microbiota in the Planktonic Phase of Rumen Digesta in Dairy Cows

The objective of this experiment was to compare ruminal fluid samples collected through rumen cannula (RC) or using an oral stomach tube (ST) for measurement of ruminal fermentation and microbiota variables. Six ruminally cannulated lactating Holstein cows fed a standard diet were used in the study. Rumen samples were collected at 0, 2, 4, 6, 8, and 12 h after the morning feeding on two consecutive days using both RC and ST techniques. Samples were filtered through two layers of cheesecloth and the filtered ruminal fluid was used for further analysis. Compared with RC, ST samples had 7% greater pH; however, the pattern in pH change after feeding was similar between sampling methods. Total volatile fatty acids (VFA), acetate and propionate concentrations in ruminal fluid were on average 23% lower for ST compared with RC. There were no differences between RC and ST in VFA molar proportions (except for isobutyrate), ammonia and dissolved hydrogen (dH2) concentrations, or total protozoa counts, and there were no interactions between sampling technique and time of sampling. Bacterial ASV richness was higher in ST compared with RC samples; however, no differences were observed for Shannon diversity. Based on Permanova analysis, bacterial community composition was influenced by sampling method and there was an interaction between sampling method and time of sampling. A core microbiota comprised of Prevotella, S24-7, unclassified Bacteroidales and unclassified Clostridiales, Butyrivibrio, unclassified Lachnospiraceae, unclassified Ruminococcaceae, Ruminococcus, and Sharpea was present in both ST and RC samples, although their relative abundance varied and was influenced by an interaction between sampling time and sampling method. Overall, our results suggest that ruminal fluid samples collected using ST (at 180 to 200 cm depth) are not representative of rumen pH, absolute values of VFA concentrations, or bacterial communities >2 h post-feeding when compared to samples of ruminal fluid collected using RC. However, ST can be a feasible sampling technique if the purpose is to study molar proportions of VFA, protozoa counts, dH2, and ammonia concentrations.

PSXI-15 Effects of post-pyrolysis treated biochars on nutrient disappearance, methane production and ruminal fermentation of a silage-based diet in an artificial rumen system (RUSITEC)

Abstract This study investigated the effects of post-pyrolysis treated biochar on nutrient disappearance, total gas and methane (CH4) production, rumen fermentation and microbial protein synthesis in an artificial rumen system (RUSITEC) fed a barley silage-based diet. The basal diet consisted of 60% barley silage, 27% barley grain, 10% canola meal and 3% mineral/vitamin supplement (DM basis). Three spruced-based biochars, treated post-pyrolysis with either zinc chloride, hydrochloric acid/nitric acid mixture or sulfuric acid were added at 2.0% of substrate DM. In a randomized complete block design, treatments were assigned to sixteen vessels (n = 4/treatment) in two RUSITEC systems. The experiment was conducted over 15 d, with 8 d of adaptation and 7 d of sampling. Nutrient disappearance of dry matter (DM), organic matter (OM), acid detergent fiber (ADF) and neutral detergent fiber (NDF) was determined after 48 h of incubation from d 9 to 12, and microbial protein synthesis was measured from d 13–15. Data were analyzed using PROC MIXED in SAS, with the fixed effect of treatment and random effect of RUSITEC system and vessel. Biochar inclusion did not affect disappearance of DM (P = 0.49), OM (P = 0.60), CP (P = 0.14), NDF (P = 0.48), ADF (P = 0.11) or starch (P = 0.58). Biochar also had no effect on total gas production (P = 0.31) or CH4 produced expressed as a % of total gas production (P = 0.06), mg/d (P = 0.70), mg/g of DM incubated (P = 0.74), or mg/g of DM digested (P = 0.64). No effect on total VFA (P = 0.56) or NH3-N (P = 0.20) production were observed. Neither microbial protein synthesis nor total protozoa count were affected by biochar addition (P > 0.05). In conclusion, biochar inclusion in a silage-based diet did not exhibit the potential to mitigate CH4 emissions or improve digestion in a RUSITEC system.

Effects of dietary supplementation with different concentration of molasses on growth performance, blood metabolites and rumen fermentation indices of Nubian goats

BackgroundMolasses is a potential energy supplement; extensively used to improve growth performance, milk and meat characteristics in goats at relatively low concentrations of 5–40% of the diet. Few data are available concerning feeding molasses to goat kids; therefore, the current study aimed to investigate the effects of dietary supplementation with higher concentrations of molasses on growth performance, blood metabolites and rumen fermentation indices. Twenty male Nubian goat kids (4–6 months old; 9–10 kg BW) were randomly assigned to 4 groups receiving different concentration of molasses: 0% (M-0), 30% (M-30), 40% (M-40) and 45% (M-45) for 5 weeks. Feed (DFI) and water intake (DWI) were measured daily, while the blood and rumen liquor samples were collected weekly.ResultsThe DFI increased and feed conversion ratio (FCR) decreased in all molasses-supplemented groups (P ≤ 0.05), whereas DWI increased in M-30 and decreased in M-45 (P ≤ 0.05). The final BW and average daily gain (ADG) increased (P < 0.0001) in groups M-30 and M-40 compared to the control and M-45. Blood pH was significantly influenced by dietary molasses concentration (MC) and the duration of molasses supplementation (MD), where it decreased in groups M-30 and M-45 compared to the control and M-40 (P < 0.05). The MC had no significant effect on blood Hb, HCT, TLC, albumin, [K+], AST, ALT and total protozoa count (TPC), as well as ruminal-[Na+], [K+], strong ion difference concentration ([SID3]) and [NH3]; however, only [NH3] was significantly affected by MD and the interaction between MC and MD (MC × MD). Serum TP, globulins, [Na+] and [Cl−] increased (P ≤ 0.05) in all supplemented groups, while A/G ratio and [SID3] decreased (P ≤ 0.05). Ruminal pH decreased (P < 0.0001) in M-40 and M-45 compared to the control and M-30. However, [VFAs] increased (P < 0.04) in M-30 and M-40 compared to the control and M-45, while osmolality increased (P ≤ 0.05) in M-30 compared to the other groups.ConclusionsDietary supplementation with molasses at a concentration of 30% for 3 weeks improved growth performance, protein metabolism and rumen fermentation without compromising animal health, immunity, and electrolytes and acid-base homeostasis.

Effect of ammonia fiber expansion-treated wheat straw and a recombinant fibrolytic enzyme on rumen microbiota and fermentation parameters, total tract digestibility, and performance of lambs.

The objective of this study was to evaluate the effect of ammonia fiber expansion (AFEX)-treated wheat straw pellets and a recombinant fibrolytic enzyme on the rumen microbiome, rumen fermentation parameters, total tract diet digestibility, and performance of lambs. Eight rumen cannulated wethers and 60 lambs (n = 15 per diet, 8 rams and 7 ewes) were used in a replicated 4 × 4 Latin square design digestibility study and a complete randomized growth performance study, respectively. Four treatment diets were arranged in a 2 × 2 factorial structure with AFEX wheat straw (0% or 30% AFEX straw pellets on a dietary DM basis replacing alfalfa hay pellets) and fibrolytic enzyme (with or without XYL10C, a β-1,4-xylanase, from Aspergillus niger) as main factors. Enzyme was applied at 100 mg/kg of diet DM, 22 h before feeding. Rumen bacteria diversity Pielou evenness decreased (P = 0.05) with AFEX compared with the control diet and increased (P < 0.01) with enzyme. Enzyme increased (P ≤ 0.02) the relative abundancies of Prevotellaceae UCG-004, Christensenellaceae R-7 group, Saccharofermentans, and uncultured Kiritimatiellaeota. Total protozoa counts were greater (P ≤ 0.04) in the rumen of lambs fed AFEX compared with control, with enzyme reducing (P ≤ 0.05) protozoa counts for both diets. Digestibility of DM did not differ (P > 0.10) among diets, but digestibility of CP was reduced (P = 0.001), and digestibility of NDF and ADF increased (P < 0.05) as AFEX replaced alfalfa. Compared with control, AFEX promoted greater DMI (P = 0.003) and improved ADG up to 42 d on feed (P = 0.03), but not (P = 0.51) over the full ~94-d experiment. Consequently, overall G:F was reduced (P = 0.04) for AFEX when compared with control (0.188 vs. 0.199), but days on feed were lower (P = 0.04) for AFEX (97 vs. 91 d). Enzyme improved DMI of AFEX up to day 70 (P = 0.01), but did not affect DMI of the control diet. Enzyme addition improved ADG of lambs fed both diets in the first 28 d (P = 0.02), but not over the entire feeding period (P ≥ 10). As a result, G:F was improved with enzyme for the first 28 d (P = 0.04), but not overall (P = 0.45). This study shows that AFEX-treated wheat straw can replace alfalfa hay with no loss in lamb growth performance. Additionally, the enzyme XYL10C altered the rumen microbiome and improved G:F in the first month of the feeding.

Effect of Supplementation of Herbal Products as Feed Additive on Rumen Metabolites in Marwari Goats

The present study was conducted to investigate the effect of herbal products supplementation on rumen environment in Marwari goats. Marwari goats of 18-24 months of age were randomly divided into five groups (four in each) i.e. T1 (complete feed without herbal products), T2 (Complete feed + Himalayan Batisa @ 10 mg/g substrate), T3 (Complete feed+Appetonic Vet powder @ 10 mg/g substrate), T4 (Complete feed + Ruchamax @ 3 mg/g substrate) and T5 (Complete feed + Rumizyme powder @ 7.5 mg/g substrate). Rumen liquor samples were collected from each animal at 0, 2, 4, 6, 8, 12 and 18 hrs post prandial. Rumen pH was unaffected while TVFA concentration was higher (Pandlt; 0.01) in herbal product supplemented groups in comparison to un-supplemented group. The total nitrogen, non-protein nitrogen and TCA-precipitable nitrogen were higher, whereas, the ammonia nitrogen and total protozoal count were lower (P andlt; 0.01) in herbal product supplemented groups. The results are indicative of supplementation of herbal products enhance the productivity in goats by improving the ruminal environment.

A blend of essential oils improved feed efficiency and affected ruminal and systemic variables of dairy cows.

This experiment evaluated the effect of a blend of essential oils (BEO) on intake, lactation performance, diet digestibility, ruminal fermentation profile, eating behavior, body thermoregulation, blood acid–base balance, and milk fatty acid profile of lactating cows. Twenty-eight Holstein cows were individually fed a standard diet for 14 d and treatments control or BEO (a microencapsulated blend of pepper extract containing capsaicin and pure forms of carvacrol, cinnamaldehyde, and eugenol; 150 mg/kg of diet dry matter) for 56 d. Significance was declared at P ≤ 0.05 and trends at 0.05 < P ≤ 0.10. Dry matter intake (DMI) was reduced (19.5 vs. 20.1 kg/d) and milk yield was increased (30.1 vs. 30.8 kg/d) by BEO, inducing improved milk to DMI ratio (1.53 vs. 1.62). Milk fat concentration tended to be increased by BEO, but total solids yield did not differ. There was a trend for increased total tract non-neutral detergent fiber organic matter digestibility with BEO. The molar proportion of acetate in ruminal fluid was reduced (51.4 vs. 57.8%) and that of propionate was increased (26.1 vs. 31.3%) by BEO. Ruminal microbial yield and total protozoa count in ruminal fluid did not differ. Cows fed BEO ingested a greater proportion of the daily intake in the morning (30.6 vs. 36.6%) and tended to ingest a lower proportion at night, tended to have longer meals, and had fewer meals per day (11.9 vs. 13.7) and larger meal size (1.5 vs. 1.7 kg of dry matter per meal). Blood urea-N and glucose concentrations did not differ. The BEO increased jugular blood oxygenation. The sweating rate on a hot and dry day was increased (160 vs. 221 g/m2/h) by BEO. The mean rectal and skin temperatures and respiration rate did not differ, but the proportion of rectal temperature measurements ≥39.2 °C was reduced by BEO at 1400 h (17.8 vs. 28.5%) and 2000 h (23.2 vs. 34.8%). The BEO increased the secretion (g/d) of 18:2 trans-10, cis-12 and the concentration of 18:0 iso fatty acids in milk fat. When one sample of milk from BEO cows was offered with two samples of milk from control, 59% of regular consumers of milk (n = 63) identified the odd sample correctly. The gain in feed efficiency induced by BEO was associated with reduced acetate-to-propionate ratio in ruminal fluid, altered eating behavior, lower frequency of high rectal temperature, and increased blood oxygenation. Essential oils had positive effects on ruminal fermentation and systemic variables of dairy cows.

Feedlot diets with soybean oil, selenium and vitamin E alters rumen metabolism and fatty acids content in steers

The objective of this experiment was to evaluate the effect of combining selenium (Se) and vitamin E (E) on intake, total digestibility and omasum escape of fatty acids in steers fed diets supplemented with high concentration of soybean oil (SO). Five rumen cannulated Tabapuã steers (BW = 398 ± 28.7 kg) were used in a 5 × 5 Latin square design with a 2 × 2 + 1 factorial arrangement: Soybean oil diets without Se (Se-) or with Se at 5 g animal per day (Se+) combined with SO diets without vitamin E (E-) or with vitamin E at 1500 IU animal per day (E+) and an added treatment without additional oil (WAO). Diets were formulated to contain 124 g/kg of crude protein (CP) in the dry matter (DM) and included corn silage, ground corn, soybean meal, soybean oil, corn gluten meal and mineral supplement. Soybean oil was added to diets at 60 g/kg of dietary DM. Each experimental period lasted 21 days with 14 days of adaptation to the diets, and 7 days for data collection. There were no effects of combining selenium or vitamin E on DM and nutrients intake (P > 0.10). The DM intake decreased in diets with supplemental SO compared to WAO diets (P = 0.02). Soybean oil supplementation decreased the total digestibility of DM (P = 0.05), OM (P = 0.05), NFC (P = 0.04) and aNDFom (P < 0.01). However, the total EE digestibility increased (P < 0.01). Diets did not affect the efficiency of microbial protein synthesis (P> 0.10). At the same time, SO diets decreased the excretion of microbial N and the total protozoal counts (P< 0.05). There was no interaction for treatment × time on pH, VFA and NH3-N (P> 0.10). The individual VFA, mol/100 mol concentration was similar among treatments (P ≥ 0.10; Table 5). The total VFA content, mM increased 6.5 % in Se diets compared to no Se supplementation (P = 0.068). There was a reduction in the rumen NH3-N content in SO diets compared to WAO (P < 0.05). Soybean oil diets increased the concentration of polyunsaturated fatty acids (PUFA) and linoleic acid (C18:2 trans-10 cis-12; P < 0.01) in the omasum and it tended to enhance with selenium supplementation (P = 0.07). The combination of selenium and vitamin E in feedlot diets with high soybean oil inclusion, contrary to our hypothesis, do not improve rumen fermentation and nutrient utilization. Future studies should use lower inclusions of soybean oil in beef cattle diets to avoid possible suppression of supranutritional effects of selenium and vitamin E on ruminal metabolism and biohydrogenation.

Effect of dietary supplementation with Yucca schidigera powder on nutrient digestibility, rumen fermentation, ruminal enzyme activities and growth performance of buffalo calves

ABSTRACT This study was conducted to investigate the effect of dietary supplementation with Yucca schidigera powder (YSP) on nutrient digestibility, rumen fermentation, rumen enzyme activity, and growth performance of growing buffalo calves. A total of 15 buffalo calves aged approximately 8–10 months with 167 ± 3.5 kg average body weight were randomly assigned to three treatments with five calves/treatment. The dietary treatments consisted of the basal diet as control and YSP groups receiving either 1 g (T1) or 2 g (T2) YSP/ kg dry matter (DM) in the concentrate mixture. The results revealed that the digestibility of DM, ether extract (EE), and nitrogen-free extract (NFE) were significantly (P < 0.05) improved, whereas the digestibility of crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), and cellulose were decreased (P < 0.05) with addition of YSP powder. Dietary supplementation with YSP affects (P < 0.05) rumen fermentation in terms of reducing ruminal ammonia-N, total volatile fatty acids, the molar proportion of acetate, ruminal enzyme activity and the total protozoa counts. In addition, supplemental YSP, particularly 2 g/kg DM, increased significantly (P < 0.05) the daily dry matter intake of feed, daily weight gain, blood glucose, and albumin levels. It can be concluded that YSP is one of the most effective ways to improve rumen fermentation, growth performance, and mitigation of ammonia and methane in livestock production.

IMPACT OF PARTIAL REPLACEMENT OF COTTONSEED MEAL BY NIGELLA SATIVA MEAL ON NUTRIENTS DIGESTIBILITY, RUMEN FERMENTATION, BLOOD PARAMETERS, GROWTH PERFORMANCE OF GROWING LAMBS

This study was conducted to evaluate the effect of partial replacement of cotton seed meal in concentrate mixture by Nigella sativa (N. sativa) meal on nutrients digestibility, rumen fermentation, blood metabolites and performance of lambs. Eighteen of healthy Farafra male lambs aged between 5 and 6 months old and had average of 27.2 ± 1.3 kg body weights. The lambs were randomly assigned into three groups, 6 animals each lasted for 90 days. The experimental groups were a control group (CON) fed basal diet containing concentrate mixture plus wheat straw and treated groups were fed basal diet plus 33.3% (T1) and 66.7% (T2 ) as a substitution of cottonseed meal by N. sativa in concentrate mixture. The lambs were fed 65% of their requirements as a concentrate mixture based on NRC guidelines and the rest were covered from wheat straw which given as roughages ad libitum. Three digestible trials were conducted with twelve mature local rams, distributed into three group and using three experimental diets, CON, T1 andT2. In growth trail body weight were recorded and daily gain were calculated. Plasma metabolites, ALT, AST enzymes, thyroid hormones (T3 and T4) and total antioxidant capacity (TAC) were determined in blood samples. In digested trail rumen liquor samples were collected to measure the protozoal count, pH, ammonia N and total VFAs concentrations. Feed and fecal samples were analyzed using AOAC (2012). The results were statistically analyzed using of SPSS statistical package. The results refer to the body weight and daily gain in T2 group was increased as compared with T1 and CON groups. The total DM and CP intake were higher (P<0.05) in T2 group as compared with CON group. The partially substitution of cotton seed meal by N. sativa meal increased (P<0.05) the concentrations of NH3-N and total VFAs, while the total protozoal count in rumen fluids was decreased (P < 0.05) as compared with CON group. Also, the plasma cholesterol and ALT enzyme was decreased (P< 0.05) in N. sativa meal groups compared to control group. However, T3 hormone and total antioxidant capacity (TAC) were higher (P<0.05) in N. sativa groups than control group. The nutrient digestibility was increased (P < 0.05) with increasing substitution rate from 33.3 to 66.7% of cotton seed meal by N. sativa meal. It can be concluded that the partial replacement of cottonseed meal in concentrate mixture by N. sativa can be used as an unconventional protein source in lambs’ rations with no any harmful effect on performance of growing lambs..

Efficacy of dietary supplementation of Tinospora cordifolia stem in prevention of sub-acute lactic acidosis in goats

Present study was undertaken to investigate the effect of dietary supplementation of T. cordifolia for reducing the risk of lactic acidosis in goats. Jamnapari goats (10) were divided into two groups. Goats of treatment group were fed T. cordifolia stem powder @ 2% in concentrate feed for 14 days. Control animals were fed equal amount of concentrate without T. cordifolia powder. After 14 days, goats were fed overnight soaked wheat grain @ 50 g/kg body weight to induce lactic acidosis. Samples of rumen fluid at 0 and 12 h, and blood were collected on 0, 12 and 36 h of feeding of grain. Lactic acid concentration, total protozoa count and pH of rumen fluid were used as markers to assess the ameliorative potential of T. cordifolia stem. Mean lactic acid concentration, protozoa count and ammonia nitrogen of rumen fluid of T. cordifolia supplemented goats were 3.47±0.33 mg/dL, 1820.70±121.36 × 103/mL, and 2.71±0.09 mg/dL respectively on 12 h of induction of lactic acidosis. The concentrations of these parameters in control goats were 5.01±0.22 mg/dL, 1168.96±75.36 × 103/mL and 1.77±0.40 mg/dL respectively. These findings provided evidence that supplementation of T. cordifolia stem can prevent lactic acidosis in goats.

Potentials of patchouli (Pogostemon cablin) essential oil on ruminal methanogenesis, feed degradability, and enzyme activities in vitro.

The effects of patchouli essential oil (PEO) as an alternative to antibiotics on ruminal methanogenesis, feed degradability, and enzyme activities were evaluated. The basal substrate was incubated without additives (control, CTL) and with monensin (MON, 6 μM/g DM) or patchouli essential oil (PEO, 90 μg/g DM) for 24 h. In three different runs, the gas production (GP) was recorded at 2, 4, 8, 12, and 24 h of incubation using a semi-automatic system. The results revealed that MON had decreased (P < 0.05) the net GP and CH4 production and digestible and metabolizable energy relative to PEO supplementation. The in vitro truly degraded organic matter was not influenced by PEO application, while was reduced (P = 0.027) with MON. Both PEO and MON had similar reducing effect on the activity of carboxymethylcellulase (P = 0.030), in vitro truly degraded neutral detergent fiber (P = 0.010), NH3-N concentrations (P = 0.012), acetate proportion (C2, P = 0.046), C2 to C3 ratio (P = 0.023), and total protozoal count (P = 0.017). Both additives recorded similar elevating potential on the α-amylase activity (P = 0.012), propionate (C3) proportion (P = 0.011), and microbial protein (P = 0.034) compared with CTL. Effects of MON and PEO on ruminal feed degradability, microbial enzyme activities, and total protozoa counts may be responsible for modifying rumen fermentation ecology. Addition of PEO may act as a desirable alternative rumen modifier for MON in ruminant diets.

Assessment of using dried vinasse rice to replace soybean meal in lambs diets: In vitro, lambs performance and economic evaluation

Effects of replacing soybean meal (SBM) with dried vinasse rice (DVR) as an alternative source of protein were evaluated under in vitro and in vivo conditions. Protein from SBM was partially replaced by DVR protein at the levels of zero (DVR0) control, 250 (DVR250), 500 (DVR500) and 750 g (DVR750) of the original concentration. An in vitro semi-automatic system was employed to evaluate gas production, feed degradability and fermentation profile of diets. The ANOVA and regression coefficients indicated that the DVR effective level was 500 g/kg DM. An in vivo experiment on twelve Texel lambs (BW; 30.48 ± 0.45 kg) kept individually in wooden pens and allotted into randomized complete block design with 6 blocks by 2 treatments as: control (diet without DVR) and DVR (500 g/kg DM) lasted for 60 days, and the subsequent 7 days were assigned for the digestibility trial. Upon increasing dietary DVR, net CH4 production decreased quadratically (P < 0.05). Ruminal NH3-N concentration and total protozoal count decreased linearly (P < 0.05) as DVR levels increased. In vitro microbial protein and propionate proportion (C3) increased quadratically (P = 0.027 and P = 0.034, respectively), while total short chain fatty acids, acetate (C2) butyrate, isobutyrate and C2:C3 ratio decreased quadratically (P = 0.036, P = 0.020, P = 0.029, P = 0.046 and P = 0.042, respectively). Lambs fed 500 g DVR/kg DM showed higher (P < 0.001) daily gain, body weight, feed efficiency and crude protein digestibility compared to control. The DVR diet showed higher (P < 0.05) digestible, metabolizable and net energy than control. DVR500 diet reduced (P < 0.001) feed costs and increased (P < 0.001) the net profit compared to control. The use of DVR provides a promising source of both protein and energy for growing lambs with extra potentials for economic advantages without adverse effects on growth performance.

Changes in ruminal fermentation and microbial population of feedlot Nellore cattle fed crude glycerin and virginiamycin

The objective of this experiment was to evaluate the effects of crude glycerin (CG) and virginiamycin (VM) diets on ruminal fermentation and microbial population of feedlot Nellore cattle. Eight rumen fistulated bulls (BW = 600 ± 34 kg; 26 ± 3 months) were used in a replicated 4 × 4 Latin square (21-d periods) with 2 × 2 factorial arrangement of treatments: diets without virginiamycin (VM−) or virginiamycin at 25 mg/kg DM (VM+) combined with diets without crude glycerin (CG−) or CG (80% glycerol) at 100 g/kg DM (CG+). The sugar cane bagasse was used as the exclusive roughage in the proportion of 200 g/kg in dry matter of diet and crude glycerin replaced corn in the diet formulation. Ruminal samples were collected immediately before feeding and at 3, 6, 12 and 18 h post feeding on days 20 and 21 of the sampling week. Data were analyzed in a replicated 4 × 4 Latin square with a 2 × 2 factorial using the MIXED procedure of SAS (SAS Inst., Inc., Cary, NC). There were no CG × VM interactions for any variable measured (P ≥ 0.10). The intake of DM had a tendency to be greater in CG+ than CG− diets (P = 0.07). Apparent total tract digestibilities of nutrients were similar among diets (P ≥ 0.10). Diets with CG or VM had similar values of pH (mean = 6.15; P ≥ 0.10). Data showed that CG or VM did not affect the concentration of total VFA (116.92 mM; P ≥ 0.10). The proportion of propionate increased 27.5% in CG+ diets, regardless of VM inclusion (P = 0.01). Acetate:propionate ratio was lower in CG+ compared to CG− diets (3.58 vs. 2.12; P ≥ 0.10). Valerate and butyrate proportion was greater in CG+ than CG− diets (P < 0.05). The inclusion of VM or CG did not alter the relative abundance of fibrolityc bacteria (P ≥ 0.10). Total protozoa counts (P = 0.052) and Metadinium spp. (P = 0.058) had a tendency to decrease in VM+ than VM− diets (P < 0.10). Crude glycerin had positive effects on rumen fermentation products and can replace virginiamycin with increment of Megasphaera elsdenii abundance. However, combining virginiamycin and glycerin does not affect positively rumen fermentation and growth of bacteria that metabolize lactate.

Effect of feeding Acacia nilotica pods to sheep on nutrient digestibility, nitrogen balance, ruminal protozoa and rumen enzymes activity.

This study was conducted to evaluate the effect of supplying two levels of Acacia nilotica (A.nilotica) pods to rations of sheep on nutrient digestibility, nitrogen balance and rumen liquor parameters (pH, total protozoa count, protein concentration and enzymes activity). Twelve mature rams (50±1.25kg B.W.) were distributed into three groups, each with four rams. Animals in group one were considered as a control which fed a basal diet, consisting of concentrate mixture and Egyptian clover. The second group and the third one received the same basal diet with supplying the concentrate mixture by 1.5% and 3.0% of A.nilotica pods meal respectively. The experiment lasted for 3weeks. It was found that supplementation of A.nilotica pods to the concentrate mixture at a rate of 1.5% and 3.0% significantly improved the total feed intake compared to the control. The digestibility of dry matter and crude fibre was significantly reduced with A.nilotica supplements, whereas the digestibility of crude protein was significantly improved. All of nitrogen intake and N-retained were significantly increased in rams fed on concentrates with 1.5% and 3.0% A. nilotica pods when compared to the control. The pH of ruminal fluid was not affected by the dietary treatments. Nevertheless, the total rumen protozoa count was significantly decreased in A.nilotica pods supplemented groups. Also, the rumen protein concentration and the ruminal enzymes activity, especially α-amylase, cellulase and protease, were lower in A.nilotica pods supplemented treatments. In conclusions, inclusion of low levels of A.nilotica pods (1.5% and 3.0%) in the concentrates can be used as a natural protein protectant in ruminants by forming tannin protein complexes in the rumen to maximize the amino acids available in the lower digestive tract. Also, these levels can increase the protein digestibility as well as the N-retained in the body .

Effect of different levels of lucerne (Medigo sativa) in diet on rumen fermentation and energy metabolism of ewes

A study was conducted to examine the effect of different levels of dietary lucerne (Medigo sativa) on rumen fermentation and energy metabolism in ewes. Four groups of ewes (6 in each) were fed experimental ration, containing nutrients as per NRC (2001). The concentrate in ration of groups T100, T200 and T400 was replaced by lucerne hay to provide saponin at the rate of 100, 200 and 400 mg/kg body weight, respectively. Ruminal pH, protozoal count, volatile fatty acid production and ammonia nitrogen concentration were determined on 0, 3, 7, 14 and 28 days of experiment. There was no significant difference among the groups for pH, total volatile fatty acid, acetate, propionate and butyrate per cent. The total protozoa in strained rumen liquor on 0 day in the treatments T00, T100, T200, and T400 were 2.79, 2.75, 2.80 and 2.67x106/ml respectively. On 3, 7, 14 and 28 day of saponin feeding, there was significant (P<0.05) reduction in protozoal population. The ammonia nitrogen in treatments T200 and T400 were significantly (P<0.05) lower than the control group on 3, 7, 14 and 28 day of saponin feeding. Methane emission was measured in respiration chamber for 48 h in continuation. Daily methane emission in T00, T200, T200, and T400 were 10.52, 9.92, 9.84 and 8.14 l/d, respectively. Compared to T00 group, reduction in daily methane production due to saponin feeding were 5.70, 6.46 and 22.62% in T100, T200, and T400, respectively. Loss of methane energy as per cent of (digestible energy was 8.49, 7.63, 7.37 and 6.48%, respectively for treatments T100, T200, and T400. From the study, it can be concluded that lucerne saponin significantly reduced the methane production and total protozoal count in rumen liquor. It can significantly increase the nitrogen retention along with the efficiency of energy utilization in sheep.

Effect of Supplementation of Nano Zinc on Rumen Fermentation and Fiber Degradability in Goats

A study was conducted to evaluate the efficiency of nano-zinc as a feed supplement on rumen fermentation and nutrient digestibility in goats (Capra hircus). Nano-sized zinc was synthesized by using 0.45M aqueous solution of zinc nitrate and 0.9M aqueous solution of sodium hydroxide as a salt of ZnO in nano form (NZnO). The particle size thus obtained was 74 nm and later it was confirmed to be zinc by using TEM-EDAX. Twenty-four male goats were divided in four groups on the basis of BW and were supplemented with either a basal diet with concentrate and straw at 50: 50 ratio (Control) alone or supplemented with 50 ppm zinc from inorganic ZnO (IZn-50), 50 ppm zinc from NZnO (NZn-50) or 25 ppm zinc from NZnO (NZn-25). The digestibility of DM, OM, CP, EE, total carbohydrates, and nutritive value of the diets in terms of DCP, TDN (%) and ME (Mcal/kg) did not vary (P>0.05) among treatment groups. The ADF and cellulose digestibility was significantly higher (P<0.05) in all three zinc supplemented groups than control. Supplementation of graded doses of NZn did not alter the individual and total ruminal VFA profile in goats, but the soluble zinc content in the rumen liquor was higher in NZn-50 than NZn-25 and control. The rumen pH and protozoa count was higher in NZn-50 than control, IZn-50, and NZn-25. Nano Zn at 50 mg/kg DM altered the rumen pH, total protozoa count, fibre degradation and soluble zinc content in goats without affecting the individual and total VFA profile. It is concluded that nano Zn can be supplemented at half the dose of inorganic Zn without affecting rumen VFA profile, rumen soluble Zn content in goats.

Clinical and laboratory investigations on Sub-acute ruminal acidosis (SARA) in Buffalo Calves

Sub-acute ruminal acidosis (SARA) is a common digestive disorder occurring in ruminants which has a great economic importance associated with decreased animal performance, decreased animal productivity and farm profitability. The aim of this study was to study the occurrence of sub-acute ruminal acidosis in Egyptian buffalo calves and investigate the most evidence clinical signs and biochemical changes associated with the disease. This study was carried out on 30 male Egyptian buffalo calves in farm of Veterinary Medicine collage, Suez Canal University, Ismailia, Egypt. 80 blood samples and ruminal fluids from diseased calf (at the onset of the appearance of the symptoms and on the 4th day of the treatment), and 20 blood samples and ruminal fluid from control ones were collected. The clinical signs were complete anorexia with cessation of rumination, yellowish-white diarrhea without systemic changes and ruminal atony. The biochemical analysis showed a highly significant reduction in serum level of potassium and chloride and highly significant increase in serum glucose and lactate level with a non-significant change in serum levels of sodium and total proteins in diseased calves suffered from sub-acute rumen acidosis. Meanwhile, ruminal fluid of diseased calves revealed a highly significant increase in the mean value of lactate level with a non-significant change in sodium, potassium and chloride level. Ruminal fluid of affected calves appeared milky-gray in color, a slight souring odor with an aqueous consistency. In addition, there were a highly significant reduction in rumen pH, the activity of ruminal protozoa (±) and total protozoal count with a highly significant retardation of SAT and MBRT.

Comparison of non-encapsulated and encapsulated active dried yeast on ruminal pH and fermentation, and site and extent of feed digestion in beef heifers fed high-grain diets

The objective of this study was to determine whether feeding ruminally protected active dried yeast (ADY) exhibits postruminal activity in comparison with feeding non-protected ADY assessed by measuring feed intake, ruminal pH and fermentation, and site and extent of feed digestion in finishing heifers. A combination antibiotic was used as a positive control. Five Angus beef heifers with ruminal cannulas (body weight of 650±48.8kg) were used in a 5×5 Latin square design with 21-d periods and 1 week of washout between each period. The five treatments were: 1) control (no ADY and no antibiotics), 2) antibiotics (ANT; 300mg monensin+110mg tylosin/d), 3) ADY (1.5g ADY/d), 4) encapsulated ADY (EDY; 3.5g/d containing 1.5g ADY and 2g capsule), and 5) mixture of ADY and EDY (MDY; 1.5g ADY+3.5g EDY/d). The ADY was encapsulated using barley hordein and glutelin extracted from barley grain. The stability of encapsulated yeast in the rumen and its release in the intestine were validated in vitro. Intake (kg/d) of dry matter (DM) was not affected by treatments. Ruminal pH, total volatile fatty acid (VFA) concentration, and NH3-N concentration did not differ among treatments, whereas molar proportion of acetate and ratio of acetate to propionate were greater with yeast addition than ANT. No treatment effects on flows of organic matter (OM) and starch to the omasum were observed, whereas flows of neutral detergent fibre (NDF) were greatest with ANT, lowest with EDY and intermediate with control, ADY and MDY (P<0.02). Digestibility of OM in the rumen tended (P<0.09) to be less with EDY or MDY than control or ANT, but no difference in ruminal digestibility of NDF and starch was observed among treatments. In contrast, greater postruminal digestibility of OM (P<0.01) and NDF (P<0.03) was observed with either EDY or MDY versus control and ANT. Digestibility of OM and NDF in the total digestive tract was also greater (P<0.01) with EDY or MDY than control. No treatment effect was observed on the flows of N to the omasum or microbial protein synthesis. Although digestibility of N in the rumen was not different, the digestibility of N in the total digestive tract was greater (P<0.02) with EDY or MDY than control or ANT. Supplementation of ADY or MDY tended (P<0.10) to have greater gene copy numbers of R. flavefaciens compared with ANT. Total protozoa counts were greater (P<0.01) in the rumen of heifers supplemented with ADY or MDY compared with control or ANT. These results demonstrate the postruminal activity of ADY and indicate the potential of feeding protected yeast to ruminants to increase intestinal digestibility of nutrients.

Effects of feeding different levels of dried orange pulp and recycled poultry bedding on the performance of fattening lambs.

The effects of dietary feeding different levels of recycled poultry bedding (RPB) and dried orange pulp (DOP) on the performance of fattening Shal lambs (initial BW of 28 ± 2.2 kg) were assessed using a factorial experiment (2 × 3) with a completely randomized design. Six diets, containing different levels of RPB (0 or 160 g/kg of DM) and DOP (0, 110, or 220 g/kg of DM), were randomly assigned to 6 groups of 6 lambs each for a 74-d period (14 d for adaptation and 60 d for data collection). Diets were offered as total mixed ration to ensure 10% of orts. Feed intake, growth, diet digestibility, microbial nitrogen (N) synthesis (MNS), N retention, rumen fermentation parameters, and blood metabolites were determined. Data were analyzed using the PROC MIXED of SAS. Increasing RPB and DOP levels in the diet of the lambs improved ( < 0.05) DMI, ADG, and G:F. Diet digestibility was not affected by dietary feeding of RPB ( > 0.05), but increased as DOP level increased in the diet ( < 0.05). Feeding RPB and DOP had no effects ( > 0.05) on the ruminal pH. The ruminal total VFA concentration, molar proportion of acetic acid, and acetate-to-propionate ratio increased ( < 0.05) with the increasing dietary levels of RPB and DOP, while ammonia N concentration, propionic acid proportion, total protozoa count, and subfamily number decreased ( < 0.05). Including RPB and DOP in diet enhanced ( < 0.05) MNS and N retention. Feeding RPB-containing diets caused ( < 0.05) an increase of plasma glucose concentration and decreases ( < 0.05) of cholesterol and urea N. As the dietary level of DOP increased, the plasma concentrations of glucose, triglycerides, and urea N reduced ( < 0.05). The plasma antioxidant power was not affected ( > 0.05) by feeding RPB, but increased ( < 0.05) with increasing DOP level in diet. The animal performance reached its greatest value with simultaneous feeding of 160 g of RPB and 220 g of DOP per kg of diet DM. It has been concluded that the partial dietary substitution of RPB (instead of soybean meal, wheat bran, and sugar beet pulp) or/and DOP (instead of barley grain and corn grain) in fattening Shal lambs had positive effects on feed intake, diet digestibility, ruminal microbial N, growth, and N retention. Synchronized feeding of the great levels of RPB (as an N source) and DOP (as an energy source) increased utilization efficiency of these byproducts in the fattening lambs.