Compost Derived Substances Decrease Feed Protein N Mineralization in Swine Cecal Fermentation

Abstract

Objectives of this study were to investigate urban biowastes as sustainable source of soluble biobased products (SBO) for use in animal diet and, possibly, to assess product chemical nature-performance relationships. Thus, five different materials sourced from biowastes processed by anaerobic and/or aerobic fermentation were treated to yield five different SBO. The products were first characterized for their chemical nature. Afterwards, they were tested as diet supplements to modulate pig's cecal fermentation of a protein feed. In vitro fermentation of the protein feed was performed using the cecal content collected from slaughtered pigs as incubation liquor. The experimental plan comprised 29 treatments distributed over the 5 SBO used at 5-6 doses each in the 0.1-1.4% concentration range, compared to a SBO free control. During the 24 h in vitro fermentation, gas and liquor samples were analyzed for total gas volume vs. time production, and for ammonia and volatile fatty acids concentration. The results showed the investigated SBO to be significantly different for both their chemical composition and in their effects on the measured fermentation indicators. All materials showed significant effects already at the lowest 0.1% concentration. However the SBO isolated from composted residues decreased ammonia production, whereas the SBO isolated from the digestate of the food residues' anaerobic treatment had the opposite effect. Ammonia production was found to be directly correlated with isobutyric and isovaleric production. The results clearly pointed out reduced proteolysis and N mineralization by 7-17% caused by compost sourced SBO. These findings have relevant implications for the economics and environmental impact of the animal production industry.

Pigs’ Husbandry as Case Study to Test Effects of Vegetable Residues’ Hydrolysates on Animals

“…The SBO used in the pigs' husbandry study is the same as the one used in the pigs in vitro study (Montoneri et al, 2013) and in the rabbits in vivo study (Biagini et al, 2016). They were obtained by hydrolysis in alkaline water of composted urban private gardening residues and public park trimmings collected in the province of Torino, Italy (see Section 2).…”

“…Humic substances isolated from soil or fossils are efficient for use as diet supplement in animal husbandry (Montoneri et al, 2013;Biagini et al, 2016). Use of SBO, in place of HS, appears highly desirable for reasons linked to the greater availability of biowastes and to the need to reduce landfill areas for biowaste disposal.…”

“…These facts offer worthwhile scope for investigating the full potential feasibility of SBO to enter the market. Sortino et al (2012), Montoneri et al (2013) and Biagini et al (2016) have dedicated studies to assessing the performance and safe use of SBO. Sortino et al (2012) carried out an on field tomato cultivation study, adding SBO to the cultivation soil.…”

“…The authors concluded that the potential adverse environmental impact of periodically repeated applications of SBO to the same soil should raise no more concern than that contributed by conventional mineral and organic fertilizers. Montoneri et al (2013) performed an in vitro fermentation study to test SBO as diet supplements to modulate pig's cecal fermentation of a protein feed. They added SBO at 0.05-0.2 % level in the fermentation slurry.…”

Soluble Bio-based Substances Obtained from Urban Wastes: Isolation and Characterization

“…1.2); e.g. in the formulation of detergents-textile dyeing baths, emulsifiers [15], auxiliaries for soil/water remediation [16] and enhanced oil recovery [17], flocculants, dispersants and binding agents Solid residue recovered after 270 days aerobic biodegradation of plant residues UB CV T360 Solid residue recovered after 360 days aerobic biodegradation of plant residues for ceramics manufacture [11], nanostructured materials for chemical [18] and biochemical catalysis [19], plastic materials [20], soil fertilizers and plant biostimulants for agriculture [21,22] and animal feed supplements [23,24]. Such variety of applications is possible due to the fact that SBO is a mixture of molecules with molecular weights comprised in a wide range over 5 kD which contain a variety of functional groups (see virtual molecular fragments in Fig.…”