Evaluation of Bacterial Diversity in a Swine Manure Composting System Contaminated With Veterinary Antibiotics (VAs)

The objective of this work was identify microorganisms present in swine effluent composting system, under the contamination by most use veterinary drugs in Brazil. The composting took place for 150 days, where was addition of 200 liters of manure (these 25 liters initially contaminated with 17 antibiotics) in 25 kg of eucalyptus wood shavings. Microorganisms were measured at times (0 until 150 days), and were identified in the V3-V4 regions of the 16S RNAr for Bacteria, by means of next-generation sequencing (NSG). The results showing 7 different Bacteria Phyla and, 70 Bacteria Genus identified (more than 1% significance), in total there were more than 26 phyla and 585 genera of bacteria. The genus Brucella was found during mesophilic and thermophilic phases, this genus, not yet been reported in article involving composting process. These results suggested the potential of adaptation of the bacterial community with antibiotics denoted through the antibiotics.

Anaerobic co-digestion of swine manure and forage at two harvesting ages

ABSTRACT: The co-digestion of swine manure with vegetable waste is an alternative that can increase the production of biogas and methane generated by the isolated digestion of manure. However, recommendations that are based on the best ratio between manure and forage, as well as the age of harvest, are still scarce in the literature. This study was conducted to evaluate inclusions (0, 25, 50, 75 and 100%) of the total solids (TS) of Elephant grass (Pennisetum purpureum Schum) harvested at two ages medium age (MA) at 45 days of growth and advanced age (AA) at 90 days in co-digestion with swine manure, using an entirely randomized design in a 5x2 factorial scheme. Batch digesters were used and biogas production was monitored for 12 weeks. There was influence of forage age (P <0.05) on the degradation of solids and neutral detergent fiber, with higher values for the substrates containing MA forage. The highest CH4 yields were obtained by the substrates containing MA forage in the inclusion of 27.7 and 31.6%, being 253.7 and 222.2 L of CH4 per Kg of total or volatile solids. The age of the forages influenced the onset and persistence of biogas production, being advantageous only in the inclusion of 25% of MA forage. The AA forage inclusion is not recommended for co-digestion with swine manure.

Effects of animal manures on enzymes activities and physico-chemical properties of a degraded humid ultisol

Application of animal manures for soil amendment plays a major role in the improvement of soil properties and enzymatic activities of a degraded Ultisol. This study assessed the effects of poultry manure (PM) and swine manure (SM) on the activities of catalase and urease enzymes and some soil properties. The PM and SM were applied at the rate of 30 t ha–1 each on experimental plots arranged in a randomized complete block design with three replicates. Soil samples were collected at day 0, 14, 28, 42, 56, 70 and 84 from 0-15 and 15-30 cm depths and analyzed for catalase and urease enzymes and some soil properties using standard procedures. The results showed increase in soil pH (in H2O) from 4.0 to 5.4 following manure application. At 0-15 cm soil depth, PM and SM recorded 28.1 and 28.8% increases in soil pH (in H2O), respectively. Soil organic carbon was highest (2.6 g kg–1) at 0-15 cm depth for soil amended with SM while the lowest value of 1.1 g kg–1was obtained at 15-30 cm depth for soil unamended with SM. In PM-amended soil, catalase activities ranged from 1.32 to 6.77 mg g–1 while its activities in SM-treated soil significantly (p < 0.05) varied between 1.55 and 8.11 mg g–1. Urease showed ranges of 0.72-3.90 mg g–1 and 0.96-4.71 mg g–1 in PM-amended and SM-treated soils, respectively. The results uphold that animal manures improve soil properties and are enzymatically controlled.