Nitrogen in Stored Poultry Litter: Uric Acid and Xanthine

Abstract

Laboratory incubations of four broiler litter (BL) samples at 30°C were performed to investigate the effect of water content on the decay of uric acid nitrogen (UAN) and xanthine nitrogen (XN). UAN and XN concentrations increased in all samples during a period of 1 to 8 d before declining for the remaining 30 d. The increases may be the result of guanine and adenine catabolism. The slopes of linear equations fit to the natural log of the observations from 16 sampling points over 38 d were compared using the GLM procedure in SAS and results indicate that both UAN and XN decay significantly ( = 0.05) more rapidly with increasing water content (θ). A second study showed significant effects in one of three samples on the decay rate of UAN with additions of flue-gas desulfurization (FGD) gypsum or alum at a water content of 750 g kg BL. The decay rate of XN was not significantly affected. Finally, a simple two-point sampling study on the effect of water potential for the estimation of first order rate equation constants showed a positive relationship between the rate of UAN and XN decay over 28 d as a function of water potential (ψ): UAN = 0.0054 × ψ + 0.1010 ( = 0.9987) and XN = 0.0066 × ψ + 0.1101 ( = 0.9285). This is the first study of UAN and XN decay in BL and the findings add to our understanding of mineralizable N from BL.

Effect of Select Tannin Sources on Pathogen Control and Microbial Nitrogen Metabolism in Composted Poultry Litter Intended for Use as a Ruminant Crude Protein Feedstuff

“…Variability in nitrogen concentrations in different litter sources is not unexpected, however, as numerous compositional, environmental, or managerial factors such as types of bedding sources used, ventilation, number of flocks reared, moisture, and humidity as well as temperature can affect nitrogen status ( 32 ). As reported earlier ( 8 , 30 , 33 ), uric acid increased in concentration as early as 3 days after the beginning of composting in the present experiments thereby adding support to the conclusion that the nitrogen in uric acid may exist in a reversible flux between the end products of uric acid degradation and uric acid synthesis as proposed by Mowrer et al ( 33 ). It seems reasonable to suspect that xanthine oxidase activity may catalyze the transformation of available purines to uric acid during the early, aerobic period of composting; however, it has been reported that xanthine oxidase activity may be inhibited by tannins ( 26 , 34 , 35 ).…”

“…Increased uric acid concentrations in the poultry litter would yield a valuable source of crude protein when used as a ruminant feedstuff. Uric acid concentrations in the poultry litter used in the two experiments of this study ranged from 0.33 (experiment 2) to 1.98 (experiment 1) μmol/g of litter dry matter (the equivalent of 56 to 332 mg/kg of litter dry matter, respectively) were considerably lower than reported by Mowrer et al ( 30 ) but were within the range reported earlier ( 31 ). Variability in nitrogen concentrations in different litter sources is not unexpected, however, as numerous compositional, environmental, or managerial factors such as types of bedding sources used, ventilation, number of flocks reared, moisture, and humidity as well as temperature can affect nitrogen status ( 32 ).…”

Effect of low‐temperature drying on the nitrogenous compounds and inositol phosphates in broiler chickens and cecectomized laying hen excreta

“…These reactions may be accompanied by the loss of excreta organic matter because some compounds, such as ammonia and carbon dioxide, are volatile. Shifts in the chemical compounds of poultry excreta are initiated immediately after voiding (Mowrer et al 2014). The extent depends on the surrounding temperature, pH, and dry matter of the excreta, among other factors (Elliott & Collins 1982).…”

“…Shifts in the chemical compounds of poultry excreta are initiated immediately after voiding (Mowrer et al 2014). The extent depends on the surrounding temperature, pH, and dry matter of the excreta, among other factors (Elliott & Collins 1982).…”