Analysis of the Intestinal and Faecal Bacterial Microbiota of the Cervidae Family Using 16S Next-Generation Sequencing: A Review.

The Cervidae family has a wide distribution due to its adaptation to numerous ecological environments, which allows it to develop a diverse microbial community in its digestive tract. Recently, research has focused on the taxonomic composition and functionality of the intestinal and faecal microbiota of different cervid species worldwide, as well as their microbial diversity and variation under different associated factors such as age, sex, diet, distribution, and seasonal variation. In addition, there is special interest in knowing how cervids act as reservoirs of zoonotic pathogenic microorganisms, which represent a threat to public health. This review provides a synthesis of the growing field of microbiota determination in cervids worldwide, focusing on intestinal and faecal samples using 16S next-generation sequencing. It also documents factors influencing microbial diversity and composition, the microorganisms reported as pathogenic/zoonotic, and the perspectives regarding the conservation of these species. Knowing the interactions between bacteria and cervid health can drive management and conservation strategies for these species and help develop an understanding of their evolutionary history and the interaction with emerging disease-causing microorganisms.

Enhancing Pectin Particles with Polymer Additives: Mitigating Rumen Degradation and Minimizing Yellowish Milk Color in Grazed Cows.

The pigments consumed in grazing give the milk from dual-purpose cows raised in tropical conditions a yellowish color, affecting the quality and price of the milk. This study aimed to develop an economical method with supplementary pectin to antagonize the availability of carotenes by designing microparticles with shellac and palm oil as a viable alternative to protect pectin degradation against rumen microbes. Three preparations of microparticles based on citrus pectin were synthesized: unprotected (PnP), protected with palm oil (PwP), and protected with palm oil and shellac (PwPL) microparticles. Samples were roughly characterized by spectroscopy and electron microscopy techniques. The effect of PnP, PwP, and PwPL on blood metabolites and physicochemical characteristics of the milk of grazing lactating cows was evaluated through in vivo assays. The release of citrus pectin from microparticles was determined as uronic acids using solutions with distinct pH, whereas its degradation was studied using in situ tests. Results revealed that PnP, PwP, and PwPL are amorphous structures with sizes that range from 60 to 265 nm or 750 to 3570 µm and have surface charges that range from -11.5 to -50.2 mV. Samples exhibited characteristic peaks during FTIR analyses that corresponded to O-H, C=O, and COOCH3 groups and bands within the UV-vis region that indicated the absorption of pectin. The EDS analysis revealed the presence of carbon, oxygen, or calcium in samples. The release of uronic acids was higher at pH 2-3 with PwPL. The in situ degradability of PnP, PwP, and PwPL was 99, 28.4, and 17.7%, respectively. Moreover, PwPL decreased the blood concentration of glucose, cholesterol, and lactate. In contrast, 100 g of pectin per animal daily during the feed process reduced yellow coloring. In conclusion, designing particles protected with lipids and polymers as shellac is an economical method that resists degradation at pH levels greater than five.

Foliage of Tropical Trees and Shrubs and Their Secondary Metabolites Modify In Vitro Ruminal Fermentation, Methane and Gas Production without a Tight Correlation with the Microbiota.

Ruminants, mainly cattle, contribute to greenhouse gases (GHG) emissions as methane (CH4) is produced by ruminal fermentation. Hence, various anti-methanogenic feed strategies have been studied, including the use of plants with secondary metabolites. This study evaluated in vitro ruminal fermentation metrics, microbial composition by digital droplet PCR (ddPCR) and the CH4 production of the foliage of several tropical trees and shrubs: Leucaena leucocephala, Moringa oleifera, Albizia lebbeck, Enterolobium cyclocarpum, Piscidia piscipula, Brosimum alicastrum, Lysiloma latisiliquum, Guazuma ulmifolia, Cnidoscolus aconitifolius, Gliricidia sepium and Bursera simaruba, using Cynodon plectostachyus grass as control. The results showed a wide variation in the chemical composition of the foliage, as well as in the ruminal microbiota. The crude protein (CP) content ranged from 11 to 25%, whereas the content of condensed tannins (CT) and saponins (S) was from 0.02 to 7%, and 3.2 to 6.6%, respectively. The greatest dry matter degradability (DMD) after 72 h was 69% and the least 35%, the latter coinciding with the least gas production (GP). A negative correlation was found between the CT and CH4 production, also between protozoa and fungi with the SGMT group of archaea. We concluded that the foliage of some tropical trees and shrubs has a high nutritional value and the potential to decrease CH4 production due to its CT content.

Interplay between feed efficiency indices, performance, rumen fermentation parameters, carcass characteristics and meat quality in Pelibuey lambs.

Feed efficiency was measured in thirty Pelibuey noncastrated male lambs using the residual feed intake (RFI) and residual intake and gain (RIG). The lambs were fattened for 92 d and then slaughtered, with the aim of identifying the interplay between feed efficiency indices (FEIs) and performance, rumen fermentation parameters, carcass characteristics and meat quality traits from the 15 intermediate and most extreme lambs for each FEI. The mean values of the classes were -0.09, 0.00, and 0.09 kg DM/d for low, medium and high RFI, respectively. The RIG indicators were 2.6, -0.1, and -2.7, for high, medium and low, respectively. The lambs with high-RIG had a higher (P ≤ 0.05) average daily gain and improved feed conversion. Lambs with low-RFI and high-RIG had higher (P < 0.05) values of meat cooking loss. Efficient lambs had improved feed utilization without affecting the carcass characteristics or meat quality (except for cooking loss).

Effectiveness and optimum level of protected methionine in fattening pig diets / Efectividad y nivel óptimo de metionina protegida en dietas para cerdos en engorde / Eficácia e nível ideal de metionina protegida em dietas para suínos de engorda

Abstract Background: Methionine (Met) requirements have not been clearly established for fattening pigs due to their metabolic interrelationships and its bioavailability for protein synthesis. Objective: To determine the optimum level of regular crystalline or protected Met in pig diets from nursery to finishing. Methods: A total of 48 crossbred pigs (11.74±1.72 kg of initial body weight) were used. The treatments consisted of adding four levels (0.00, 0.05, 0.10, 0.15% in addition to dietary content) and two types of Met (regular and protected) to pig diets. Results: Nursery, Finishing I, and II pigs fed protected Met increased daily feed intake (DFI; p≤0.10). Protected Met raised daily weight gain (DWG) in nursery pigs and increased backfat thickness (BT) in nursery and grower pigs (p≤0.10). In Finishing I pigs, protected Met increased DWG and improved carcass characteristics (p≤0.10). In nursery and grower pigs, an extra 0.15% Met decreased feed:gain ratio (FGR; p≤0.10). In grower and Finishing II pigs fed extra 0.05% Met improved DWG and extra 0.10% Met reduced plasma urea concentration (p≤0.10). Conclusions: Feeding protected Met in pig diets increases DWG, DFI and BT. Increasing 0.05-0.15% Met level improves FGR, DWG, potentially reducing nitrogen excretion to the environment.

Resumen Antecedentes: los requerimientos de metionina (Met) para cerdos en crecimiento no han sido claramente establecidos, lo que se debe a sus relaciones metabólicas y su biodisponibilidad para la síntesis proteica. Objetivo: determinar el nivel óptimo de Met regular o protegida en dietas para cerdos en crecimiento. Métodos: Se utilizaron un total de 48 cerdos híbridos (11,74±1,72 kg peso vivo inicial). Los tratamientos consistieron en niveles incrementales (0,00, 0,05, 0,10, 0,15% adicionales al contenido de la dieta) y dos tipos de Met (regular y protegida) en la dieta. Resultados: los cerdos en iniciación, Finalización I, y II, alimentados con Met protegida tuvieron un mayor consumo diario de alimento (DFI; p≤0,10). La Met protegida aumentó la ganancia diaria de peso (DWG) durante la etapa de iniciación, e incrementó el grosor de la grasa dorsal (BT) en iniciación y levante (p≤0,10). Durante Finalización I, la Met protegida aumentó la DWG y mejoró las características de la canal (p≤0,10). Durante iniciación y levante, 0,15% extra de Met disminuyó la conversión alimenticia (FGR; p≤0,10). Los cerdos en levante y Finalización II alimentados con 0,05% extra de Met mejoraron la DWG y con 0.10% extra de Met redujeron la concentración de urea en plasma (p≤0,10). Conclusiones: el uso de Met protegida incrementa DWG, DFI y BT. El aumento del nivel de Met de 0,05-0,15% mejora FGR y DWG, y podria disminuir la excreción de nitrógeno al ambiente.

Resumo Antecedentes: os requisitos de metionina (Met) para suínos de engorda não foram claramente estabelecidos devido às suas relações metabólicas e sua biodisponibilidade para a síntese de proteínas. Objetivo: determinar o nível ideal de Met regular ou protegida em dietas para suínos de engorda. Métodos: foram utilizados 48 suínos híbridos (11,74±1,72 kg de peso vivo inicial). Os tratamentos consistiram em quatro níveis (0,00, 0,05, 0,10, 0,15% mais) e dois tipos (regular e protegida) de Met em dietas para suínos de engorda. Resultados: suínos no início, finalização I e II alimentados com Met protegida aumentaram o consumo diário de ração (DFI; p≤0,10). Met protegido aumentou o ganho de peso diário (DWG) em suínos na iniciação e, aumentou espessura da gordura dorsal (BT) em suínos em iniciação e crescimento (p≤0,10). Nos suínos finalização I, Met protegido aumentou DWG e melhorou as características do canal (p≤0,10). Para suínos de iniciação e crescimento, 0,15% extra de Met diminuiu conversão alimentar (FGR; p≤0,10). No crescimento e finalização II, a adição de 0,05% de Met melhoraram o DWG e com 0,10% reduziram a concentração de uréia (p≤0,10). Conclusões: o uso de Met protegida melhora DWG, DFI e BT. O nível de Met aumentado de 0,05-0,15% melhora FGR e DWG; além disso, a excreção de nitrogênio ambiental pode ser diminuída.

Uso de disacáridos y carbón activado para preservar consorcios de bacterias ruminales celulolíticas liofilizadas / Use of disaccharides and activated carbon to preserve cellulolytic ruminal bacterial consortiums lyophilized

RESUMEN Objetivo. Determinar la fermentación in vitro de consorcios bacterianos ruminales celulolíticos (CBC) conservados por liofilización usando carbón activado, maltosa y lactosa como preservadores. Materiales y métodos. Un CBC se aisló de fluido ruminal de una búfala de agua en medios selectivos celulolíticos. Los CBC se liofilizaron con carbón activado (CA), lactosa (LA) o maltosa (MA) como preservadores y sin preservador (SP). El diseño experimental fue completamente al azar para medir biogás a diferentes intervalos de tiempo; así como, un diseño completamente al azar con arreglo factorial 4x3, los factores fueron preservadores (SP, CA, LA y MA) y tiempo de fermentación (24, 48 y 72 h) para pH, nitrógeno amoniacal (N-NH3), degradación de materia seca (DMS) y de fibra detergente neutro (DFDN), actividad enzimática celulasas y la población de bacterias totales. Resultados. LA produjo mayor biogás acumulado a las 72 h y parcial a partir de las 12 h (p≤0.05). SP no mostró diferencias (p>0.05) en celulasas, conteo de bacterias total, DMS y DFDN en los tiempos de fermentación evaluados con el resto de los preservadores. Conclusiones. La producción de biogás parcial y acumulada, el aumento en la tasa de degradación de 8.3 y 91.1 % en la DMS y DFDN de las 24 a 72 h (p≤0.05) con el preservador LA, muestran que la lactosa puede usarse como preservador de bacterias celulolíticas ruminales.

ABSTRACT Objective. To determine in vitro fermentation of cellulolytic ruminal bacterial consortia (CBC) preserved by lyophilization using activated carbon, maltose and lactose as preservatives. Materials and methods. A CBC was isolated from the ruminal fluid of a female water buffalo in selective cellulolytic media. The CBC were lyophilized without preservative (SP), activated carbon (CA), lactose (LA) o maltose (MA) as preservatives. The experimental design was completely random to measure biogas at different time intervals; as well as completely random with 4x3 factorial arrangement, factors were preservative [SP, CA, LA and MA] and fermentation time (24, 48 and 72 h) for pH, ammoniacal nitrogen (NH3-N), dry matter degradation (DMD), neutral detergent fiber degradation (NDFD), enzymatic activity cellulases and total bacteria population. Results. LA produced higher accumulated biogas at 72 h and partial biogas after 12 h (p≤0.05). SP did not show differences (p>0.05) in cellulases, total bacteria population, DMD and NDFD in the fermentation times evaluated with the rest of the preservative. Conclusions. The production of partial and accumulated biogas, the increase in the degradation rate of 8.3 and 91.1% in the DMD and NDFD from 24 to 72 h (p≤0.05) in the LA preservative, show that lactose can be used as a preservative of ruminal cellulolytic bacteria.

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

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. © 2018 Society of Chemical Industry.

Effect of vitamin E on milk composition of grazing dairy cows supplemented with microencapsulated conjugated linoleic acid.

The objective of this study was to evaluate the effect of vitamin E on the fat content and fatty acid profile of grazing dairy cows supplemented with microencapsulated conjugated linoleic acid. Eight New Zealand Holstein cows in a rotational grazing system were used, in a crossover design, randomly assigned to four treatments: control (base diet with microencapsulated conjugated linoleic acid) and three levels of vitamin E (control with 4,000; 8,000; and 12,000 IU/cow per day). All the cows received a supplement apportioning 5 g of cis-9, trans-11, and 5 g of trans-10, cis-12 of conjugated linoleic acid. Moreover, they each received 4-kg dry matter (DM) concentrate and 3.2-kg DM corn silage every day. There were no differences in dry matter intake, milk production, milk composition (fat, protein, and lactose), or fatty acid profile as an effect of vitamin E, and fat content remained under 3 % in all treatments. Therefore, under the conditions that this experiment was carried out, high concentrations of vitamin E in the diet of grazing dairy cows do not inhibit milk fat depression associated with conjugated linoleic acid. It also has no effect on the fatty acid profile of the milk.

Manejo nutricional en corrales de engorda / Nutritional management in feedlot

El manejo nutricional en un corral de engorda debe enfocarse a los siguientes aspectos: recepción, prevención de acidosis, uso de aditivos alimenticios, agente anabólicos y programas de finalización. El uso de aditivos es una de las alternativas más importantes para reducir los costos de alimentación o para obtener mayor eficiencia alimenticia. Algunos de ellos tienen efectos secundarios como la reducción de acidosis y coccidiosis, otros reducen la incidencia de abscesos hepáticos y problemas de salud animal. La tasa de degradación de almidón es muy importante en la selección del grano para el programa de nutrición del corral de engorda