Isolation and characterization of Lactobacillus strains as potential probiotics for chickens

The ban on the use of antibiotics as growth promoters for poultry production in many countries has led to increasing interest to use probiotics as an alternative. In the present study, some Lactobacillus strains were isolated from chicken intestines, identified and assessed (in vitro) for their ability to survive and colonize the gastrointestinal tract (GIT), with a view to select suitable strains as potential probiotic candidates for chickens. Out of 42 isolated strains, three isolates, identified as Lactobacillus strains based on initial identification and tolerant to acid and bile based on preliminary screening using turbidity (optical density) as a measurement of growth, were selected for detailed identification and further in vitro assays. The three isolates were identified to species level using carbohydrate fermentation profile analysis and 16S rRNA gene sequencing. Results showed that all three strains belonged to Lactobacillus salivarius. The three L. salivarius strains were then assessed for their ability to tolerate the stress conditions in the GIT and capacity to adhere to the intestinal epithelial cells using in vitro assays of acid, bile and pancreatic enzyme tolerance measured by viable colony counts, and adhesion assay using Caco-2 cell line. The results showed that all three L. salivarius strains exhibited good tolerance to acid, bile and pancreatic enzymes and a strong ability to adhere to intestinal epithelial cells. Thus, they would be able to survive the stress conditions of GIT, as well as to attach and colonize the GIT, and could be considered as good potential candidates for probiotics of chickens

Manipulation of rumen fermentation and methane gas production by plant secondary metabolites (saponin, tannin and essential oil) – a review of ten-year studies

A wide range of plant secondary metabolites (PSM) have been shown to have the potential to modulate the fermentation process in the rumen. The use of plants and plant extracts as natural feed additives has become an interesting topic not only among nutritionists but also other scientists. Although a large number of phytochemicals (e.g. saponins, tannins and essential oils) have recently been investigated for their methane (CH4) reduction potential, there have not yet been major breakthroughs that could be applied in practice. However, the effectiveness of these PSM depends on the source, type and the level of their presence in plant products. The aim of the present review was to assess ruminal CH4 emission through a comparison of integrating related studies from published papers, which described various levels of different PSM sources being added to ruminant feed. Apart from CH4, other related rumen fermentation parameters were also included in this review

Papaya (Carica papaya) leaf methanolic extract modulates in vitro rumen methanogenesis and rumen biohydrogenation

Papaya leaf methanolic extract (PLE) at concentrations of 0 (CON), 5 (LLE), 10 (MLE) and 15 (HLE) mg/250 mg dry matter (DM) with 30 mL buffered rumen fluid were incubated for 24 h to identify its effect on in vitro ruminal methanogenesis and ruminal biohydrogenation (BH). Total gas production was not affected (P > 0.05) by addition of PLE compared to the CON at 24 h of incubation. Methane (CH4) production (mL/250 mg DM) decreased (P < 0.05) with increasing levels of PLE. Acetate to propionate ratio was lower (P <0.05) in MLE (2.02) and HLE (1.93) compared to the CON (2.28). Supplementation of the diet with PLE significantly (P <0.05) decreased the rate of BH of C18:1n-9 (oleic acid; OA), C18:2n-6 (linoleic acid; LA), C18:3n-3 (linolenic acid; LNA) and C18 polyunsaturated fatty acids (PUFA) compared to CON after 24 h incubation, which resulted in higher concentrations of BH intermediates such as C18:1 t11 (vaccenic acid; VA), c9t11 conjugated LA (CLA) (rumenic acid; RA) and t10c12 CLA. Real-time PCR analysis indicated that the total bacteria, total protozoa, Butyrivibrio fibrisolvens and methanogen population in HLE decreased (P <0.05) compared to CON, but the total bacteria and B. fibrisolvens population were higher (P < 0.05) in CON compared to the PLE treatment groups

Effects of feeding goats with Leucaena leucocephala and Manihot esculenta leaves supplemented diets on rumen fermentation profiles, urinary purine derivatives and rumen microbial population

The effects of different levels of Leucaena leucocephala and Manihot esculenta leaves’ supplementation on in vitro gas production, rumen fermentation and microbial populations and urinary purine derivatives (PD) were investigated. Seven treatment groups – T1:C/rice straw (RS) (40:60) (Control); T2:C/RS/leucaena leaves (40:45:15); T3:C/RS/leucaena leaves (40:30:30); T4: C/RS/leucaena leaves (40:15:45); T5:C/RS/cassava leaves (40:45:15); T6:C/RS/cassava leaves (40:30:30) and T7:C/RS/cassava leaves (40:15:45) – were used in this experiment. In the in vitro study, acetate, propionate, butyrate and total VFA were found to increase significantly in T7. No significant difference was observed in in vitro gas production except the control diet although in vitro dry matter digestibility (IVDMD) was recorded significantly decreased. Determination of urinary PD, rumen fermentation and microbial population were done using 21 local Boer goats. Rumen NH₃-N, acetic and total VFA production were found to improve (P < .05) in all supplemented group. Significant (P < .05) reduction was noted in the urinary allantoin production and total PD at T7. The populations of total protozoa and Ruminococcus flavefacien had significantly increased (P < .05) while Ruminococcus albus, and Fibrobacter succinogenes were significantly reduced (P < .05) in supplemented group. In conclusion, the result from the present study suggested that 25% of L. leucocephala leaves diet and 50% of M. esculenta leaves diet can be incorporated in the goat diet so as to improve the nutritive value of poor quality diet

Effects of vitamin E, inorganic selenium, bacterial organic selenium, and their combinations on immunity response in broiler chickens

Background: Selenium (Se) and vitamin E (Vit E) can act synergistically and affect biological processes, mainly antioxidant and immunity. The use of excess dietary Vit E and Se in animals' feed could enhance immune response and induce disease resistance. Moreover, different Se sources may provide different alterations in the immune system. Accordingly, the aim of the current study was to assess the impact of dietary supplementation of Vit E, inorganic Se (sodium selenite, SS), bacterial organic Se of ADS18, and their different combinations on the plasma immunoglobulins, ceacum microbial population, and splenic cytokines gene expression in broiler chickens. Results: Present results showed that, Se and Vit E synergistic effect was clear in plasma IgM level at day 42 and in splenic cytokines expression (TNF-α, IFN-γ, IL-2, IL-10). The combination of 0.3 mg/kg ADS18-Se with 100 mg/kg Vit E showed the highest IgM level compared to Vit E- SS complex. The combination of either SS or ADS18-Se with Vit E had no significant effect on IFN- γ and IL-10 compared to Vit E alone, while Vit E alone showed the significantly lowest TNF-α compared to the Se combinations. Supplementation of 100 mg/kg Vit E had no effect on microbial population except a slight reduction in Salmonella spp. The main effect of Se sources was that both sources increased the day 42 IgA and IgG level compared to NS group. ADS18-Se modulate the caecum microbial population via enhancing beneficial bacteria and suppressing the E-coli and Salmonella spp. while both Se and Vit E factors had no effect on lymphoid organ weights. Conclusions: The inclusion of 100 mg/kg Vit E with 0.3 mg/kg ADS18-Se, effectively could support the immune system through regulation of some cytokines expression and immunoglobulin levels more than using ADS18-Se alone, while no difference was observed between using SS alone or combined with Vit E

Towards immunity of oil palm against Ganoderma fungus infection

The first record of Ganoderma can be traced back to the Pharmacopoeia written by Chinese scientists in first century B.C. Several Ganoderma species are known as “white rot” fungi, which cause the display of the white cellulose on wood by degrading the lignin component. Ganoderma boninense is the main agent of basal stem rot (BSR) disease, as a persistent problem in the oil palm (Elaeis guineensis, Jacq.) cultivation that needs to be controlled. Oil palm, which is the main host of this pathogen, is an economically important crop grown in Southeast Asia, Africa, and America. Due to the negative effects of Ganoderma on the plants, especially on oil palm, this review focuses on the mechanisms of Ganoderma infection and its control, the importance of lignin and silicon (Si) to plant defense. This review also explores different methods for Ganoderma control and techniques for producing less susceptible oil palm. Genetic manipulation of oil palm for enhancing resistance to Ganoderma is also discussed

Conjugated linoleic acid: a potent fatty acid linked to animal and human health

Conjugated linoleic acid (CLA) is a mixture of isomers of linoleic acid (C18:2 n-6), which is mostly found in the ruminant meat and dairy products. The CLA is known to have many potential health benefits, and considered a potent powerful fatty acid, which is linked to animal and human health. The present work aims to discuss the source and production, mechanism of action, and effects of CLA on humans, poultry and ruminants by reviewing the recent studies carried out on CLA. Despite most of recent studies indicating beneficial effects of CLA on improving body weight control parameters, its effects on reducing risk factors of cardiovascular diseases (CVD), inflammation, blood glucose and insulin are still controversial, and need to be further studied in different hosts

Dietary supplementation of papaya (Carica papaya l.) leaf affects abundance of Butyrivibrio fibrisolvens and modulates biohydrogenation of C18 polyunsaturated fatty acids in the rumen of goats

Saturated fatty acid (SFA) produced as a final product of rumen biohydrogenation (BH) by rumen microbes is harmful to human health because of increasing the risk of heart-related diseases. The objectives of this study were to test the effect of papaya leaf (PL) on the BH of C18 polyunsaturated fatty acids (PUFA), fatty acid composition and bacterial abundance in the rumen of goats. Three rumen fistulated male goats were assigned in a 3 × 3 latin square design using three levels of PL; no addition of PL in basal diet (control, CON, 50% concentrate +50% alfalfa hay), 25% of alfalfa hay in basal diet replaced by PL (medium PL, MPL) and 50% of alfalfa hay in basal diet replaced by PL (high PL, HPL). Supplementation of the diet with PL significantly (p < .05) decreased the rate of rumen BH of C18:2n-6 (linoleic acid, LA) at different hours of sampling at the higher inclusion of PL (HPL), resulted in the reduction (p < .05) of C18:0 (stearic acid, SA) in the rumen liquor. The population of Butyrivibrio fibrisolvens as determined by the real-time PCR was higher (p < .05) for MPL (5.78 cell/mL) and HPL (6.09 cell/mL) in the rumen of goats as compared with the CON (5.50 cell/mL). The current results imply that PL supplementation could be a useful feeding strategy to modulate the BH of LA in rumen of goat

Ruminal methanogenesis and biohydrogenation reduction potential of papaya (Carica papaya) leaf: an in vitro study

An in vitro gas production study was conducted to test the effect of papaya leaf (PL) at different concentrations of 0 (CON), 10% (Low PL: LPL), 15% (Medium PL: MPL) and 25% (High PL: HPL) of replacement with alfalfa hay (AH) in substrate (50% AH + 50% concentrate) on rumen methane (CH4) production, rumen biohydrogenation (BH) of polyunsaturated fatty acid (PUFA) and rumen microbial population. PL at different concentrations were mixed with 30 ml of buffered rumen fluid and were incubated for 24 h. Methane production (ml/250 mg DM) declined at a decreasing rate (linear p = 0.03) with increasing levels of PL. The acetic/propionic ratio (1.80) was lowest (p < 0.05) for HPL compared with CON (2.04), LPL (1.95) and MPL (1.89). Supplementation of the diet with PL significantly (p < 0.05) decreased the rate of BH of C18:2n-6 (LA) and C18 PUFA after 24 h of incubation especially at the higher inclusion rate, resulting in an increased production of rumen BH intermediates such as conjugated linoleic acid (CLA), whereas saturated fatty acid (SFA) decreased in the rumen fluid after 24 h of incubation. Estimates of rumen microbial population using real-time PCR assay showed a reduction in total methanogens (p < 0.05) in MPL (−12%) and HPL (−16%) and increase in total bacteria population (HPL: +5%) and Butyrivibro fibrisolvens (MPL: +20; HPL: +23%) among PL treatment groups compared with the CON group. These results emphasise PL as a beneficial feed material for ruminants