This study was performed to evaluate the effect of adding a mixture of peppermint, thyme and rosemary essential oils (EOs) in a ratio of (3:1:2), respectively, to the diet, on growth performance, rumen and blood parameters of fattening lambs. Twenty-one Mehraban lambs with an average weight of 29.80 kg were randomly allocated to one of three diets: 1) control, 2) base diet+1.25ml of EOs and 3) base diet+2.5ml of EOs. Daily weight gain was greater in the groups receiving the EOs than in the control, although this increase was mainly due to the interactions of treatment over time. Feed consumption and feed conversion ratio compared to the control did not altered. The total concentrations of VFAs and acetate in the groups receiving EOs decreased (P<0.05), while the concentration of propionate increased (P<0.05) at the level of 2.5ml of EOs and isovalerate increased (P<0.05) in both levels of EOs compared to the control. Total population of protozoa, rumen pH and ammonia nitrogen concentration were not affected by treatments. Glucose concentration increased at high level of EOs (P<0.05). Concentrations of urea, cholesterol, triglycerides, creatinine, total protein and albumin did not altered. The number of red blood cells, hemoglobin, hematocrit, number and percentage of white cells including lymphocytes and eosinophils were not affected by treatments but the percentage of monocytes decreased (P<0.05) at low level of the EOs. The results of this experiment showed that the addition of mixture of EOs to the diet did not have a significant effect on performance parameters and immune system of lambs, although it reduced the total concentration of VFA and acetate and increased the concentration of propionate.

Introduction: Generally, most feeds used in livestock nutrition are deficient in some nutrients, and require nutritional supplements. Among the supplements, micro and macro minerals are particular importance. Selenium (Se) plays an important role in the reproductive function and immune system and is known as an antioxidant and catalyst for the production of thyroid hormone. It is believed that low selenium absorption in ruminants is due to the deficiency of selenium in ration and its conversion into insoluble form. Nano-particles are smaller and more active than larger particles. The importance of Selenium for rumen microorganisms are not entirely clear. Also, selenium is an essential trace element, and its importance for animal health and productivity has been well confirmed. Selenium has known to be involved in enzyme activity and preventing oxidative damage to body tissue. Selenium plays important roles in antioxidant systems, prevents cell damage and is necessary for growth, fertility, and immune system in farm animals. Recently, nano-elemental Se has attracted wide spread attention due to its high bioavailability and low toxicity, because nanometer particulates exhibit novel characteristics, such as great specific surface area, high surface activity, a lot of surface active centers, high catalytic efficiency and strong adsorbing ability and over and above the character of low toxicity of Se0. Dietary selenium is an essential trace element for animals and humans with a variety of biological functions. It plays important roles in the regulation of thyroid hormone metabolism, cell growth and antioxidant systems thus, together with alphatocopherol prevents cells against oxidative stress damage, also these compounds are necessary for growth, fertility, and immune system health in animals and humans. The objective of this research was to investigation the effects of different sources of selenium on digestion characteristics of concentrate mixture of diets in high producing lactating dairy cows using in vitro gas production technique. Materials and Methods: Four male ruminally fistulated sheep, average 43± 4. 8 kg of BW, were used in a replicated 4×4 Latin square experiment. Sheep were fed twice daily (08: 00 and 18: 00 h) at maintenance nutrition requirements with a basal diet consisting of 400 g/kg (dry matter) DM of basal concentrates and 600 g/kg DM of forage. Sheep were placed in metabolic cages individually and fresh water was freely available during the experimental period. This experiment was conducted in four periods of 28 days with 21 d adaptation period and 7 d for data tacking. Treatments were: 1. Basal diet 2. Basal diet + 0. 3 ppm nano selenium, 3. Basal diet + 0. 3 ppm seleno methionine, 4. Basal diet + 0. 3 ppm selenite sodium. The rumen fluid was mixed with artificial saliva (1: 2 ratio, respectively) in lab, and then nano-Selevels and seleno methionine added to it. In gas production method, 300 mg of each treatment weighted and incubated for 2, 4, 6, 8, 12, 16, 24, 36, 48, 72, 96 hours. In order to determine the effects of different forms of selenium on rumen parameters, concentrations of VFA and NH4, value of pH and population of protozoa were examined. Samples of rumen fluid were collected through the cannula at 4 h after feeding on days 19 and 20 of each collection period for pH, NH3-N, and volatile fatty acids (VFAs) determination. Ruminal pH was immediately measured using an electric pH meter. The samples were subsequently stored frozen at − 20 ◦ C until analyses. Results and Discussion: Potential of gas production (fraction A) of nano, organic and inorganic treatments were higher (201. 9, 344. 0, 321. 7 and 319. 8 ml in control, nano, organic and mineral treatments, respectively) compared to control treatment (P<0. 05). The nano selenium treatment had higher VFA concentration (109. 83, 98. 00 and 89. 83 mmol/l in nano, organic and mineral treatments, respectively) when compared with organic and inorganic treatments (P<0. 05). Rumen NH4 concentration was not affected by treatments. The organic treatment caused a significant increase in total protozoa population when compared with nano and inorganic treatments (P<0. 05). Conclusion: The results indicated that selenium supplementation in ruminant diet improves ruminal nutrients degradability's compared to control. Therefore, the use of nano-Se resulted to increase digestibility and fermentation of nutrients resulted improved rumen microorganisms activities. Although nano and organic selenium was better than inorganic treatment in ruminal degradability and rumen parameters, however there was not any significant differences between these two treatments.

Introduction: On the one hand, among many types of bioactivities, plants secondary metabolites have repetitively demonstrated antibacterial and antimicrobial activities. On the other hand, the growing concerns over resistance of bacteria to antibiotics and chemical residues in animal derived foods have attracted the attention of many towards utilization of natural antibacterial and antimicrobial compounds. Phytochemicals exhibit antibacterial, antiviral, and antifungal activities against a wide range of pathogenic and non-pathogenic microorganisms. The antimicrobial properties of phytochemicals as feed additives have been explored in livestock production system (Patra 2012). In the recent decade, plant-extracted antibacterial biomolecules have successfully substituted antibiotics, other chemotherapeutic agents, and chemical and growth promoting antibiotic feed additives in many research studies. Of many classes of phytochemicals, saponins have shown various types of bioactivities including antibacterial effects. These biomolecules have various mechanism of actions against bacteria. Saponins s could suppress the bacteriolytic activity of rumen ciliate protozoa thus enhancing the total microbial protein flow from the rumen. Moreover, saponins also have selective antibacterial effects which may prove useful in, for example, controlling starch digestion (Wallace et al 2002). Studies have investigated the beneficial effects of saponin rich licorice root extract on ruminal microbial population and rumen fermentation. It is of note that information on the effect of phytochemicals on ruminal microbial fermentation at low pH is scarce. The effects of plant extracts on ruminal microbial fermentation are pH-dependent. Most of the research have focused on the effects of phytochemicals on high-forage diets at pH over 6. 2. Microbial populations and ruminal fermentation conditions varies between the cattle fed high-concentrate and high-forage diets leading to different final intestinal pH conditions. Ideally, a natural feed additive with the capacity of replacing ionophores of the high concentrate diet in low-pH environment is required. Therefore, we hypothesized that saponin rich licorice root extract could exert some antimicrobial activities at low pH. Hence, the objective of this experiment was to study the effect of licorice extract on in-vitro gas production parameters, pH, volatile fatty acids (VFA) and ammonia-N concentration as well as protozoa populations in diets containing different levels of concentrate to forage ratio. Material and methods: Dehydrated licorice extract was obtained from Zagros Company (Kermanshah). Two experimental diets with different forage to concentrate ratio (40 to 60% or 60 to 40 %) were formulated. Licorice extract was added to diets at three levels of 1, 2 and 3 mg /liter of incubation media. The saponin content of licorice extract was 134. 75 mg/g of dried licorice extract. For in-vitro gas production, rumen fluid was taken from two rumen fistulated Kordish rams. For measuring gas production, 200 mg of experimental diets with four levels of licorice extract (0, 1, 2 and 3 mg/L incubation medium) were incubated with 40 ml of buffered-rumen fluid for 120 hours. The cumulative produced gas was recorded at different times of incubation and gas production parameters were fitted with Blummel et al. equation (2003). Organic matter digestibility (OMD) was estimated after 24 hours of incubation (Menke and Steingass 1988). N-ammonia concentration was measured based on the method of Broderickand Kang et al. (1980). Rumen protozoa were identified according to the method of Dehority et al. (2003). After 24 h incubation, 5 ml of buffered rumen fluid was pipetted into a screw-capped test tube containing 5 ml of formalin. Thereafter, two drops of brilliant green dye (2 g brilliant green and 2 ml glacial acetic diluted to 100 ml with distilled water) were added to the test tube, mixed thoroughly, and allowed to stand overnight at room temperature. Total and differential counts of protozoa were made with five replications. In-vitro rumen concentration of volatile fatty acids (VFA) was measured by gas chromatography (Ottenstein and Bartley 1971). All in-vitro gas production trials were carried out in three runs. Rumen fermentation parameters, protozoa population and OMD data were analyzed in a factorial arrangement based on a completely randomized design and gas production data was analyzed in a factorial arrangement based on a complete randomized block design using Proc GLM of SAS software. The differences among treatments were evaluated using Tukey adjustment when the overall F-test was P ≤ 0. 05. Trends were declared when 0. 05 < P ≤ 0. 10. Results and discussion: The results showed that the interaction of diets and licorice extract were not significant on in-vitro gas production, rate of gas production, estimated OMD, ammonia-N concentration, pH, total protozoa population, Entodinium, Epidinium, Diplodinium, Eudiplodinium and Isotricha population and in-vitro ruminal concentrations of total VFA, acetate, propionate, butyrate, isobutyrate, valerate and isovalerate. The effect of diets on gas production (P≤ 0. 05) and estimated OMD (P<0. 01) was significant. High concentrate diets compared with low concentrate diets had greater gas production and estimated OMD. In disagreement with our findings, saponin decreased gas production in low concentrate diet (Yogianto et al 2014) and adding saponin to diet containing high level of concentrate increased gas production (Aazami et al 2013). Furthermore, high concentrate diet had lower OMD compared with the low concentrate diet (Yogianto et al 2014). Diets containing high concentrate had lower acetate and greater isovalerate concentrations (P<0. 01). Addition of licorice extract reduced estimated OMD and total protozoa and Entodinium population (P<0. 01) and tended to increase total VFA concentration (P=0. 09) while decreasing the concentration of isovalrate (P=0. 06). Conclusion: Based on our results, it is concluded that licorice extract had no effect on fermentation parameters of diets containing different concentrate: forage ratios. Further studies are necessary to determine the effectiveness of saponin-containing plants extracts on rumen microbial fermentation and digestion kinetics.

This study was carried out to determine of the effects of lasalocid on ruminal fermentation parameters in Ghezel sheep. Sixteen male Ghezel sheep were used allocated in completely randomized design. The diet containing of 2. 9 ME (Mcal/kg DM) and 150 g/kg DM CP was formulated based on NRC requirement consisting of 400 g kg-1DM alfalfa, 488 g kg-1 DM barley grain, 200 g kg-1 DM soybean meal, 589 g kg-1 DM, corn grain and 20 g kg-1 DM limestone containing predicted metabolizable energy 2. 9 Mcal kg-1 DM and containing crude protein 150 g kg-1 DM. The treatments containing different level of ionophore (20 ppm, 25 ppm, 30 ppm and 35 ppm). The experiment period was 21 days. The rumen fl uid was collected using stomach tube at 2 and 4 h after morning feeding. The fl oatation and sedimentation time, methylene blue reduction time, pH, total ammonia nitrogen and total VFA in ruminal samples were determined. The ruminal pH, total VFA, sedimentation and fl oatation time and methylene reduction time were not significant differences. The effect of lasalocid on ruminal ammonia concentration was significant difference (P<0. 05). The results showed that the lasalocid had no effect on ruminal parameters except of ruminal ammonia-N resulted low proteolytic bacteria activity.

The present study was conducted to assess the effects of salinomycin antibiotic at different doses (0, 2, 4, 8 and 16 mg/L) on gas production kinetics, some rumen digestion and fermentation indices, and at the doses of 0, 4 and 16 mg/L on some rumen microbial populations using Real-time PCR method. For this purpose, three ruminally fistulated male rams were used to collect the rumen fluid for incubations of 144 h in the first and incubations of 24 h in the second phase of the experiment. Results indicated that the gas produced at all the measured times and the asymptotic gas production (A) increased linearly and quadratically with increasing doses of salinomycin. However, the gas production rate (µ ) was not affected by the treatment. The gas produced after 24 h of incubation (GP24), in vitro true dry matter degradability (IVTDMD), in vitro true organic matter degradability (IVTOMD) and total volatile fatty acid (TVFA) concentration increased in a linear and quadratic manner, but partitioning factor (PF) decreased and microbial biomass (MB) and ammonia concentration were not affected by salinomycin. Among the rumen microorganisms, the relative population of protozoa and Fibrobacter succinogens decreased at the highest dose of salinomycin and those of fungi, methanogens and Clostridium aminophilum remained unaffected by salinomycin. These results revealed that salinomycin has a positive impact on rumen digestion and fermentation indices, which regarding recent findings on its effects in preventing different kinds of human cancer, it can be used as feed additive in animal nutrition.

In a 3×3 Latin square design three treatments including: 1) basal diet (control) in addition to diets containing 2) 100 and 3) 200 mg/day of Peppermint essential oils were tested in three ruminally cannulated male sheep with average body weight of 50± 3 kg. Rumen liquor was sampled 3 hours after feeding to determine rumen pH, N-NH3 and volatile fatty acids. On the last day of each period, blood samples were taken 3 hours after feeding via jugular vein to determine glucose, triglyceride, cholesterol, HDL, LDL, NEFA, total protein, albumin and globulin. Dry matter intake and digestibility of DM, CP, NDF, ADF and EE; the ruminal parameters and blood metabolites were not affected by the treatments