ABSTRACT The present study intended to identify the effects of the Saccharomyces cerevisiae yeast on production performance and parameters related to the quality of layers’ eggs. Effects of yeast on immune titers after routine vaccinations against Newcastle disease and infectious bronchitis were also studied. Fayoumi chicken (n=288) were divided in four groups (72 in each), and Black Australorp (n=288) in four groups (72 in each). Both had 12 weeks of age and were kept in 08 groups (3 replicates per treatment). Hens were fed a controlled diet along with the addition of 0.5g, 1.0 g, and 1.5 g of S. cerevisiae per kg of feed, till 25 weeks of age. Feed intake and egg production were measured on a daily basis, while body weight gain and egg weight were measured weekly. Egg quality parameters were evaluated by picking 5 eggs from every group weekly. Birds were vaccinated for Newcastle disease (ND) and infectious bronchitis (IB) at the 18th week. Subsequently, 10 days after vaccination, antibody titers were determined by Hemagglutination Inhibition and Enzyme Linked Immunosorbent Assay for both diseases. Results showed no significant effect of S. cerevisiae on layers’ weight gain and feed intake. However, egg production was increased in the experimental group. Moreover, yeast supplementation impacted positively on birds’ immune system. In conclusion, probiotic supplementation improved birds’ egg production and immunity.

Abstract Oil sands surface mining operations in northeastern, Alberta, Canada produce enormous volumes of fluid fine tailings, an aqueous suspension of fine clays, sand, unrecovered bitumen, and diluent hydrocarbons. The tailings are deposited and retained on-site in large settling basins where the colloidal solids sediment and consolidate very slowly by gravity and pore water collects at the surface for re-use. Tailings “biodensification”, mediated by indigenous microbes that produce methane and/or carbon dioxide, is a phenomenon observed in situ and in vitro whereby tailings with active anaerobic microbial communities consolidate and de-water faster than predicted by gravitational (self-weighted) consolidation alone. To exploit this phenomenon, we used organic amendments to stimulate endogenous anaerobic tailings microorganisms. Tailings from three different operators were amended with agri-business by-products, placed in 100-mL microcosms and 1.5-L settling columns, and monitored for methanogenesis, pore water recovery, and solids densification. Several amendments increased methane production and accelerated biodensification compared to unamended and negative controls. Hydrolyzed canola, blood meal, bone meal and glycerol generally accelerated biodensification, stimulated methane production and supported growth of methanogens and fermentative microbes. Amendment altered the chemistry of the tailings, generally decreasing pH, increasing conductivity and magnesium, potassium, sodium, and bicarbonate concentrations. Biodensification is a potential engineered technology for accelerating water recovery and reducing the volume of stored oil sands tailings.

Resumen Introducción: La extracción de hidrocarburos en el Noreste de Alberta, en Canadá, genera una gran cantidad de residuos conocidos como “arenas de alquitrán”. Las arenas de alquitrán son una suspensión acuosa de arcillas finas, arena, betún de petróleo e hidrocarburos. Estos residuos son depositados y retenidos en estanques de sedimentación, donde los sólidos coloidales precipitan y se concentran muy lentamente por efecto de la gravedad y el agua intersticial que se libera se colecta para reúso. La concentración, también llamada densificación, de las arenas de alquitrán mediada por los microorganismos nativos que producen metano o dioxido de carbono, es un fenómeno observado in situ e in vitro, a través del cual, los residuos se precipitan, y se libera agua intersticial más rápidamente que la sedimentación por gravedad. Método: En este trabajo, se aplicaron enmiendas orgánicas para estimular la actividad de microorganismos nativos de los estanques de sedimentación, con el objetivo de acelerar la densificación y liberación de agua intersticial. Se utilizaron muestras de arenas de alquitrán de tres distintas compañías petroleras (Syncrude Canada Ltd.; Suncor Energy Inc.; y Shell Albian Sands), y se enmendaron en condiciones anaeróbicas con seis materias primas de la industria agrícola: (residuos de la extracción de aceite de canola; harina de huesos y harina de sangre de res hidrolizados; suero de leche hidrolizado; glicerol y granos secos de maíz usados para la producción de cerveza y bioetanol). Se utilizó acetato de sodio como control positivo de metanogénesis y 2-bromoetanosulfonato (BES) 10 mM como inhibidor específico de metanogénesis. Los experimentos de densificación se realizaron en botellas serológicas de 100 ml en condiciones anaeróbicas, y en columnas de sedimentación de vidrio de 1.5 L; y se siguió la producción de metano, recuperación de agua intersticial y densificación. Se tomaron muestras durante los experimentos para la cuantificación de bacterias por número más probable, y para el seguimiento de los cambios en la dinámica de comunidades microbianas por pirosecuenciación de los genes ribosolames 16S. Al término de los experimentos de densificación, se realizaron algunas determinaciones de características físicas y químicas de las arenas densificadas y del agua intersticial liberada. Resultados: Varias enmiendas incrementaron la producción de metano y aceleraron la densificación, en comparación con los controles negativo y sin enmienda. Residuos de canola, hidrolizados de harina de hueso, y de sangre y glicerol, aceleraron la densificación, estimularon la producción de metano e incrementaron el crecimiento de microorganismos metanogénicos y fermentadores. Las enmiendas alteraron algunos parámetros químicos de las arenas de alquitrán sedimentadas; generalmente disminuyeron el pH, incrementaron la conductividad eléctrica e incrementaron las concentraciones de magnesio, potasio, sodio y bicarbonato. Discusión o Conclusión: La Densificación mediada por microorganismos representa una tecnología potencial para acelerar los procesos de recuperación de agua intersticial y densificación de las arenas de alquitrán almacenadas en los estanques de precipitación de las industrias petroleras en Canadá.

Abstract In the present investigation functional, technological, and rheological attributes of probiotic yoghurt were studied during refrigerated storage (4 °C) for 28 days. The different preparations of probiotic yoghurts were made from dahi microflora which was documented as probiotics. Three strains of lactic acid bacteria (LAB) i.e. S. thermophilus (S02FT), L. bulgaricus (TLB06FT) and L. acidophilus (LA06FT) were selected for formulations of probiotic yoghurt. Three sets of probiotic yoghurt including Y1: S02FT and TLB06FT (1:1ratio), Y2: S02FT and TLB06FT (1:2ratio) and Y3: S02FT, TLB06FT and LA06FT (1:1:1 ratio) along with Y0 as a control (non-probiotic strains) were prepared and stored at 4 °C for 28 days. The results showed that technological attributes of Y3 preparation had better lactic acid production (75% at 0 day and 93% at 28 days) as compared to control. Moreover, Y3 preparation had lesser synersis (20% at 0 day and 35% at 28days) as compared to other treatments i.e. Y1, Y2, Y0 that had 24, 70 and 18% synersis at 0 day of storage respectively). However, viscosity of Y3 probiotic yoghurt indicated higher values (3001 cP at 0 days and 1310 cP at 28 days) among the rest of preparations. Functional attributes of Y3 showed the better results such as viability of probiotics (40×10-6 CFU/ml at 0 day and 1.16×10-6 CFU/ml at 28 days) and antibacterial activity (7.5 mm at 0 days 7 mm at 28 days) compared to other preparations. Conclusively, Y3 formulation attained the higher sensory attributes due to its better lactic acid production, viscosity and lesser synersis values during entire study duration in formulated yoghurt.

Abstract Agricultural crops suffer many diseases, including fungal and bacterial infections, causing significant yield losses. The identification and characterisation of pathogenesis-related protein genes, such as chitinases, can lead to reduction in pathogen growth, thereby increasing tolerance against fungal pathogens. In the present study, the chitinase I gene was isolated from the genomic DNA of Barley (Hordeum vulgare L.) cultivar, Haider-93. The isolated DNA was used as template for the amplification of the ∼935 bp full-length chitinase I gene. Based on the sequence of the amplified gene fragment, class I barley chitinase shares 93% amino acid sequence homology with class II wheat chitinase. Interestingly, barley class I chitinase and class II chitinase do not share sequence homology. Furthermore, the amplified fragment was expressed in Escherichia coli Rosetta strain under the control of T7 promoter in pET 30a vector. Recombinant chitinase protein of 35 kDa exhibited highest expression at 0.5 mM concentration of IPTG. Expressed recombinant protein of 35 kDa was purified to homogeneity with affinity chromatography. Following purification, a Western blot assay for recombinant chitinase protein measuring 35 kDa was developed with His-tag specific antibodies. The purified recombinant chitinase protein was demonstrated to inhibit significantly the important phytopathogenic fungi Alternaria solani, Fusarium spp, Rhizoctonia solani and Verticillium dahliae compared to the control at concentrations of 80 µg and 200 µg.

White leghorn layer (n=2740), with 85weeksof age, were submitted to forced molting by fasting for 13 days and changes in body characteristics and subsequent laying performance during second laying cycle were evaluated. Live body weight (LBW),ovary weight (OW), oviduct weight (OvW) and oviduct length (OvL) were measured before and after fasting. Post-fasting restricted feeding was applied, initially feeding crushed corn with added 2% Ca for 20 days and thereafter layer crumble feed was offered. Layers lost 632.16g (36%) of their LBW and significant reductions of 45.32, 47.53 and 54% were observed in post-fasting/molt OW, OvW and OvL, respectively (p<0.05). Resting period was 49 days and birds consumed 4.79kg feed during resting period. Egg production reached 50% in the 3rd week and peak mean egg production (87%) was recorded between 13 to16th weeks of production. Hence, it is concluded that while molting exhausted layers, the procedure adapted to induce molting and season would be a core factor in the subsequent laying cycle egg production and gain.