Infrared attenuated total reflection spectroscopic analysis and quantitative detection of forage spectral features in ruminant systems

This study aimed to (1) access protein molecular structure profile and metabolic characteristics of model forages [Foreign sourced-origin (coded as: "FSO", n = 7 vs. Chinese sourced-origin alfalfa hay "CSO", n = 5] in ruminant systems; (2) Quantify the relationship between forage protein molecular structures and protein utilization and availability. Advanced non-invasive vibrational molecular spectroscopic technique (ATR-FTIR: Attenuated Total Reflection Fourier Transform Infrared spectroscopy) with chemometrics was applied to reveal forage protein molecular structure. Both univariate and multivariate molecular spectral analyses were applied to study molecular structure features in model forages. The molecular structure study provided the detailed protein structure profiles of Amide I and Amide II areas and height, total Amide I and II area ratios, Amide I to II height ratio as well as Amide I to II area ratio using ATR-FTIR spectroscopy. The results showed FSO and CSO had similar (P > 0.05) protein rumen degradation kinetics. However, FSO had superior quality than CSO in intestinal (IDP) and total digestible protein (TDP) and truly absorbed nutrient supply (P < 0.05). As intestinal digestion of protein, FSO was higher (P < 0.05) in protein digestion in terms of: intestinal digestibility of rumen undegraded protein (dIDP: 47.5 vs. 38.3 %RUP); Intestinal digestible protein (IDP: 17.6 vs. 13.7 %CP). As truly absorbed nutrient supply, FSO contained higher (P < 0.05) truly absorbed rumen synthesized microbial protein, absorbable rumen undegradable feed protein in the small intestine, total truly digested protein in the small intestine, metabolizable protein and Feed Milk Value (FMV^DVE: 1.2 vs. 1.1 g/kg DM). The molecular structure-nutrition interactive relationship study showed that protein molecular structure profiles were highly associated to protein rumen degradation kinetics, significantly correlated to protein subfractions, protein intestinal digestion, and truly absorbed nutrient supply in ruminant systems.

Effect of alkaline and sonication pretreatments on the rumen degradability of date palm seeds

The main objective of this research was to evaluate the effects of chemical treatment and sonication (ultrasound) processing on the fiber composition and rumen degradability of date palm seeds (DPS). In the first trial, the effects of incubation or sonication in 4% sodium hydroxide (NaOH) on DPS fiber content and ruminal degradability were evaluated. Relative to untreated seeds, the ruminal degradability of DPS neutral detergent fiber (NDF) and organic matter (OM) increased (P < 0.05) for the treated seeds and were highest (P < 0.05) for the sonicated seeds. Relative to untreated seeds, the hemicellulose and lignin content were lower (P < 0.05) for the sonicated seeds, while the cellulose content was higher (P < 0.05) for the incubated seeds. In the second trial, the effects of subjecting DPS to different sonication times (5, 10, 20, and 30 min) were evaluated. The degradability of seeds' NDF and OM were greater (P < 0.05) for the sonicated than unsonicated seeds. The highest NDF degradability was seen after 30 min sonication, whereas the OM degradability was not affected by sonication time (P > 0.05). In the third trial, the effects of subjecting DPS to sonication in different NaOH solutions (1%, 2%, 4% NaOH) were evaluated. Relative to untreated seeds, the rumen degradability of seeds' NDF and OM increased with all NaOH concentrations but was highest (P < 0.05) with the 4% NaOH. In conclusion, our results showed that treating DPS with 4% NaOH increased the seeds' ruminal degradability, and subjecting DPS to sonication further improved their degradability in the rumen.