Designing and evaluation of urea microcapsules in vitro to improve nitrogen slow release availability in rumen

Abstract

BACKGROUND: There is a growing interest in the development of novel and innovative vehicles for controlled release of urea into the rumen, aiming to provide ammonia-N for the biosynthesis of proteins of bacterial origin and to prevent urea intoxication by direct feeding to livestock. Urea microencapsulation is a system that can control the release of urea to be slow and steady. RESULTS:The amount of encapsulated urea was 69% of CSU (calcium silicate + urea + Eudragit RS100 ® + dichloromethane) and 71% of ACU (activated charcoal + urea + Eudragit RS100 ® + dichloromethane) groups (p > 0.05) The buoyancy of the microcapsules was over 50% after 12 h of agitation in both groups (CSU and ACU), producing significant differences in the volume of the organic phase factor, which was 20 mL at the lowest value (p = 0.0005). The morphology of the microcapsules produced with CSU and ACU showed no significant differences in microcapsule morphology (p > 0.05). The lower temperature (35 versus 40 ∘ C, p = 0.035) retained better morphology of the microcapsules. Regarding the in vitro ammonia-N release kinetics, unprotected urea reached a maximal peak after 6 h, while CSU and ACU took more than 24 h to reach ammonia-N released concentration. CONCLUSIONS:We stabilized the physical factors in the microencapsulation of urea that can allow slow release of rumen fluid. RESULTS AND DISCUSSIONPhase 1 Urea encapsulation Urea encapsulation was ca 65% for the APV. Urea is hygroscopic and is very soluble. 8 The proportion of encapsulated urea was J Sci Food Agric 2019; 99: 2541-2547

In vitro fermentation end-products and rumen microbiome as influenced by microencapsulated phytonutrient pellets (LEDRAGON) supplementation

“…In this study, the similarity in both in vitro degradability of IVDMD and IVOMD at 12 h after incubation could be attributed to the deceleration and increased stability of the core substrate facilitated by the microencapsulated wall of MiEn-LEDRAGON in the in vitro degradation process 53 , 54 . This effect may lead to a temporary slowdown in the efficiency of microbial decomposition, resulting in similar outcomes for a short period 55 .…”

“…The breakdown of the insoluble fraction occurred at a rate approximately four times slower than the breakdown of the soluble fraction during anaerobic digestion 52 . This leads to a decline in the microbial degradation efficiency in the rumen, causing a gradual reduction or slowdown in the degradation process, which is to achieve higher and longer stability of the core substrate within the ruminal inoculum 53 , 54 . Similarly, Ibrahim and Hassen 55 demonstrated that the slow release provided by microencapsulated tannin effectively protects the bioactive compound, leading to a slow degradation rate until it reaches the target site.…”

A new feed additive composed of urea and soluble carbohydrate coated with wax for controlled release in ruminal fluid

“…In order to circumvent these problems and obtain better efficiency in the nitrogen use by ruminal microorganisms, different types of slow-release urea (SRU) such as biuret, starea (extruded urea), urea phosphate, oil-based coatings, urea treated with formaldehyde, and urea coated with polymer were developed 3 . These products decrease the chances of intoxication and can improve bacterial growth, as they are able to maintain a constant availability of nitrogen in the rumen fluid 4 .…”

Recent progress in preparation and agricultural application of microcapsules

“…Moreover, as the most important nonprotein nitrogen source in ruminants, urea has a vital function in supplementing the protein of ruminants. By preparation sustained-release urea microcapsules based on oil and polymer, the ammonia produced by urea in the rumen is prevented from exceeding the rate of microbial utilization(Cherdthong & Wanapat, 2010;Galo, Emanuele, Sniffen, White, & Knapp, 2003;Lira-Casas et al, 2019;Ma, Wang, Hahn, & Sanchez, 2016;Pinos-Rodriguez, Peña-Avelino, González-Muñoz, Bárcena-Gama, & Salem, 2010;).…”