Tianyi Guan

Abstract

This proposed work introduces a comprehensive framework for analyzing the inorganic nutritional quality and fermentation level of Rhus typhina (Staghorn Sumac) silage produced at the Toronto Zoo. Supplemental browse silage, incorporated within the Zoo's wintertime feeding initiatives, plays a vital role in supplying nutrient-rich minerals especially during the lack of available natural forage. Nevertheless, the chemical susceptibility, and safe handling of the aforementioned, have so far defied characterization. In this context, two distinct, complementary, and integrated analytical approaches have been devised. The first approach evaluates fermentation level based on quantitative determinations of lactic, acetic, and ammonia-nitrogen contents, utilizing enzymatic UV-Visible spectrophotometry, as well as High-Performance Liquid Chromatography with Fluorescence Detection (HPLC-FLD). The other approach focuses on inorganic quality determination, specifically on gravimetric determination of total ash, and simultaneous determination of elements potassium (K), sodium (Na), calcium (Ca), magnesium (Mg), iron (Fe), copper (Cu), and zinc (Zn), achieved via air-acetylene Flame Atomic Absorption Spectrometry (air-acetylene FAAS) following nitric-acid-assisted digestion. Detailed frameworks for Quality Assurance (QA) and Quality Control (QC), including minimum calibration linearity values of 0.995, recovery, as well as precision values not to exceed 5 to 10 % relative standard deviations, have been incorporated. Data analysis methods will be introduced with both mathematical equations and R code. All digestion, extract, and analyze operations follow all established UTSC chemical lab safety regulations. The proposed set of results allows further statistical correlation, quantitative comparison, and threshold-specific categorization, particularly on separating acceptable, cautionary, and investigative samples. Both combined, the proposed study has contributed significantly within the framework of a comprehensive, reproducible, and defensible long-term nutritional approach for browsing herbivorous zoological species.

Keywords: Rhus typhina; Toronto Zoo; silage quality; fermentation analysis; Flame Atomic Absorption Spectrometry (FAAS); UV-Vis spectrophotometry; HPLC-FLD; ash content; Quality Assurance (QA); Quality Control (QC); inorganic nutrition; animal feed safety