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In order to obtain Bacillus spp. strains with probiotic activity isolates, from the cecum of backyard chicken (Gallus gallus domesticus) were selected and identified. For the isolation the method of seriated dilutions and thermal treatment (71 °C) was used, for eliminating the cells in vegetative phase and obtaining the endospores. The selection included different tests, such as: resistance to acid pH (2) and to biliary salts (1,5 g.L-1 of Ox-Bilis), antimicrobial activity against ATCC collection strains and others not belonging to official collections, and resistance to 14 antibiotic types. The data were analyzed according to simple classification design and were processed in the statistical program INFOSTAT. The characterization and identification were developed through biochemical and molecular tests (PCR). Seventy five isolates of Bacillus spp. were obtained from which only two (20 BP and 50 BP) survived the action of the acid pH and of biliary salts, showed antimicrobial activity against pathogen strains and were sensitive to 14 antibiotics. These two isolates, identified as Bacillus subtilis subsp. subtilis, showed potential to be used as probiotics. [ABSTRACT FROM AUTHOR]

In order to evaluate the effect of three zootechnical additives of Bacillus subtilis on productive and health indicators in broilers, a study was conducted in the poultry farm of the Institute of Animal Science "Mayabeque, Cuba". For such purpose 200 broilers of the Cuban breeding hybrid EB34 were used, in a completely randomized design. Four treatments were studied: T1: control group (CG), T2: C-31, T3: C-34 and T4: E-44, at a dose of 109 endospores per gram of concentrate feed. The trial lasted 42 days, and hematological, immunological, productive and health indicators were evaluated. The use of these zootechnical additives did not cause any effect at 21 days on any of the indicators; however, at 35 and 42 days the weight of the bursa of Fabricius, the spleen and the hemagglutination titers to Newcastle vaccine increased (p < 0,001). There were improvements (p < 0,001) in the hematological indicators hemoglobin, hematocrit, globulins, albumins and total proteins at 35 and 42 days of age; as well as an increase of live weight at 35 (p < 0,01) and 42 days (p < 0,001), lower intake at 42 days (p < 0,05), better conversion at 35 (p < 0,001) and 42 days (p < 0,05), and higher feed efficiency at 35 and 42 days (p < 0,001). The indicators mortality and viability did not show differences among the treatments. It is concluded that the addition of these zootechnical additives improved the productive and health responses in broilers. [ABSTRACT FROM AUTHOR]

The present study aimed to isolate and select bacteria with cellulolytic capacity, having future application as inoculum in the fibrous organic waste composting. Five sampling environments were considered: organic agriculture (AO), conventional agriculture (AQ), forest (BM); sugarcane area (RC) and compost piles (AC). For bacterial isolation the nutrient agar medium was used changing the carbon source by cellulose. The main selection criterion of the bacterial isolates was the growth on above medium and its positive reaction to congo red test, showing clear zones around the colonies. The 93 bacterial isolates obtained were subjected to Gram staining, catalase test, presence of endospores and aerobically growth; having 70 bacteria Bacillus spp. like characteristics. Their cellulolytic activities were determined and 30 bacteria produced hydrolysis halo. Eight of these bacterial isolates were selected according to the largest halo production (AO-19, AO-28, AO-29, AQ-2, BM-7, RC-2, RC-6, CR-18) and their growth at different pH (3, 5, 7, 9) and temperatures (50 and 70 °C) were evaluated. The bacteria AO-19 showed higher hydrolysis halo with 12,33 mm and growth stability at different pH and temperature levels, for which its growth dynamic and amylolytic and pectinolytic capacity was determined. According to results the bacteria AO-19 has potential to be used as inoculum in composting. [ABSTRACT FROM AUTHOR]