Dietary shifts affect the gastrointestinal microflora of the giant panda (Ailuropoda melanoleuca)

Giant pandas exhibit seasonal changes in bamboo plant part preference. The influences on the gastrointestinal tracts (GIT) microbial populations were evaluated during a 14‐month period for a pair of adult male and female giant pandas housed at the Memphis Zoo using traditional culturing methods to enumerate eight bacterial groups (total anaerobes, total aerobes (TAR), streptococci (STR), total enterics, Escherichia coli, Bacteroides spp., lactobacilli and Clostridium spp.). Both the male and female pandas altered bamboo consumption behaviours, with a sharp decrease in leaf preference in April 2010 and returning to high levels of leaf preference from June to October, corresponding to significant shifts in the densities of TAR, STR, and lactobacilli and Bacteroides spp. These findings indicate seasonal changes in food preference affect the assemblages of microbial populations within the GIT of the giant panda and contribute to a better understanding of the importance of bamboo in this species’ foraging strategy.     

Regulating effects and mechanisms of Chinese medicine decoction on growth and gut hormone expression in heat stressed pigs

Exposure to high temperatures during the summer renders pigs susceptible to severe heat stress. Our previous studies found that pig small intestine epithelial tissue became significantly damaged following exposure to heat stress, negatively affecting body weight gain. The deleterious effects of heat stress could be ameliorated using a traditional Chinese medicine decoction (CMD), sustaining normal growth while under heat stress. In the current study, we hypothesized the mechanism of CMD activity to be via regulation of gut hormones (NPY, MLN, SCT and GCG) secretion from endocrine cells, which are responsible for nutrient digestion and absorption. To test this, 36 Chinese experimental mini-pigs (2 months of age) were screened according to weight and litter origin, and divided into three treatment groups: control (23 °C for 24 h + standard feed), heat stress (HS; 26 °C for 19 h, 40 °C for 5 h + standard feed) and CMD (26 °C for 19 h, 40 °C for 5 h + standard feed supplemented with CMD); n = 12 per group. Feed intake and body weight gain were measured daily. Pigs were euthanized at days 1 and 6 after initial treatment with blood and sections of small intestine epithelial tissue collected. Serum cortisol (Cor) concentrations were determined using RIA. Endocrine cell number and structural analysis were performed using silver staining, and gut hormone secretion examined by microarray. Dietary supplementation with CMD significantly improved porcine growth performance (P < 0.05), decreased the Cor levels (P < 0.01), increased endocrine cell number as well as up-regulating neuropeptide Y (NPY), motilin (MLN) and secretin (SCT) and down-regulating glucagon (GCG) expression in pig jejunum on day 6 when compared with the HS group. Taken together, our results indicate CMD supplementation can significantly reduce the negative effects of heat stress on pig jejunum, maintaining growth performance similar to non-heat stressed animals. CMD's activity appears to be via adjusting gut hormone secretion to regulate metabolism and improve animal growth.     

Acid products adsorbed in diatomaceous earth beneficially influence the microbial environment in the gastrointestinal tract of piglets post-weaning

The effect of two acid products, CH01-141 and CH01-186 on the microbial ecosystem and on survival of the diarrhoea causing E. coli O149:K88 in the gastrointestinal tract of newly weaned four-week-old piglets was investigated. The results showed that piglets fed with the CH01-141 and CH01-186 products had a significantly lower pH and significantly higher concentration of lactic acid in the distal small intestine as compared with piglets fed the control diet without any acid product. The CH01-141 product also tended to increase the number of lactobacilli in the small intestine and decreased the number of yeasts throughout the gastrointestinal tract as compared with the control group. Besides this, the in vitro survival rate of E. coli O149:K88 tended to be lower in content from the distal small intestine of the CH01-141 fed piglets. In conclusion, the acid products, especially CH01-141, may have a beneficial effect on diminishing pathogenic bacteria, such as E. coli O149:K88, and thus improving gut health of piglets around weaning.     

A Comparative Study of Serum Biochemistry,Metabolome and Microbiome Parameters of Clinically Healthy,Normal Weight,Overweight, and Obese Companion Dogs

The aim of this study was to compare fecal microbiome, plasma, fecal and urine metabolomes, and serum biochemistry of adult companion dogs according to body condition scores. Blood, serum/plasma, urine, and fecal samples were collected from 66 clinically healthy, adult companion dogs of either normal weight (NW), overweight (OW), or obese dogs (OB). analyses included fecal microbiome analyses via 16S ribosomal RNA gene amplicon; sequencing, nontargeted plasma, fecal, and urine metabolomics using liquid chromatography/gas chromatography-mass; spectrometry, and serum biochemistry for each dog. Few significant differences in serum biochemistry and fecal microbiome Operational Taxonomic Unit (OTU) were found between weight groups and there was high OTU variation between individual dogs. NW dogs had higher relative abundance of the genus Eubacterium (log-fold change 4.3, adjusted P value?=?.003) and lower relative abundance of the family Bifidobacteriaceae (log-fold change ?3.6, adjusted P value?=?.02) compared to OB dogs. The microbiome of NW dogs had higher OTU richness compared with OB dogs. Metabolome analysis showed 185 plasma, 37 fecal, and 45 urine metabolites that significantly differed between NW and OW or OB dogs. There were notable significant differences in relative abundance of several plasma phospholipid moieties and fecal volatile fatty acids between weight phenotypes. The combinations of host and gut microbiota and metabolic shifts suggest a pattern that could help detection of early metabolic changes in overweight dogs before the development of obesity related disease. The results of this study support the need for continued investigation into sensitive measures of metabolic aberrancies in overweight dogs.     

Comparative aspects of plant tannins on digestive physiology,nutrition and microbial community changes in sheep and goats: A review

Comparative aspects of plant tannins on digestive physiology, nutrition and microbial community in sheep and goats are discussed in the context of differences due to feed intake, digestibility, utilization of nutrients and microbial community. The purpose of this review was to present an overview of the potential benefits of tannin‐containing diets for sheep and goats and specie differences in their response to tannins. It is well established that moderate level of tannins in the diet (3%–4% tannins DM) can precipitate with soluble proteins and increase protein supply to the sheep, but comparative aspects of tannin‐containing diets in sheep and goats on animal performance, digestive physiology, rumen microbial changes and potential benefits to sustainable animal production by those compounds have received little attention. In addition, developing plant‐based tannin‐containing diets for control of rumen microbiota and rumen fermentation (e.g., methane gas) would be expected to have a greater impact on the ruminant health, productivity and emission of greenhouse gasses. The positive impacts of the plant tannin compounds mainly depend on their influence on the gut microbiome diversity and ability to generate fermentation end products (short‐chain fatty acids) that have diverse biological roles. Diets which contain optimal levels of tannins have potential benefits for sustainability of small ruminant production systems. However, there is a need for an improved understanding of the utilization of tannin‐containing forages to improve their management. This implies investigations of animal responses to tannin‐containing forages or browse species and, in particular, a better understanding of the interactions that can arise between sheep and goats on digestion, DMD, rumen fermentation and microbial community changes. This knowledge could help to improve current feeding systems in terms of efficiency of feed use and environmental impacts (reduce methane gas production) and thus contribute to the development of a sustainable sheep and goat production.     

Essential oil and aromatic plants as feed additives in non-ruminant nutrition: a review

This paper summarizes the current knowledge regarding the possible modes of action and nutritional factors involved in the use of essential oils (EOs) for swine and poultry. EOs have recently attracted increased interest as feed additives to be fed to swine and poultry, possibly replacing the use of antibiotic growth promoters which have been prohibited in the European Union since 2006. In general, EOs enhance the production of digestive secretions and nutrient absorption, reduce pathogenic stress in the gut, exert antioxidant properties and reinforce the animal’s immune status, which help to explain the enhanced performance observed in swine and poultry. However, the mechanisms involved in causing this growth promotion are far from being elucidated, since data on the complex gut ecosystem, gut function, in vivo oxidative status and immune system are still lacking. In addition, limited information is available regarding the interaction between EOs and feed ingredients or other feed additives (especially pro- or prebiotics and organic acids). This knowledge may help feed formulators to better utilize EOs when they formulate diets for poultry and swine.     

Gut microbiome colonization and development in neonatal ruminants: Strategies,prospects, and opportunities

Colonization and development of the gut microbiome is a crucial consideration for optimizing the health and performance of livestock animals. This is mainly attributed to the fact that dietary and management practices greatly influence the gut microbiota, subsequently leading to changes in nutrient utilization and immune response. A favorable microbiome can be implanted through dietary or management interventions of livestock animals, especially during early life. In this review, we explore all the possible factors (for example gestation, colostrum, and milk feeding, drinking water, starter feed, inoculation from healthy animals, prebiotics/probiotics, weaning time, essential oil and transgenesis), which can influence rumen microbiome colonization and development. We discuss the advantages and disadvantages of potential strategies used to manipulate gut development and microbial colonization to improve the production and health of newborn calves at an early age when they are most susceptible to enteric disease. Moreover, we provide insights into possible interventions and their potential effects on rumen development and microbiota establishment. Prospects of latest techniques like transgenesis and host genetics have also been discussed regarding their potential role in modulation of rumen microbiome and subsequent effects on gut development and performance in neonatal ruminants.     

The importance of C,N and P as driver for bacterial community structure in German beech dominated forest soils

Among several environmental factors shaping soil microbial communities the impact of soil nutrients is of special interest. While continuous application mainly of N and P dramatically shifts community composition during fertilization, it remains unclear whether this effect is consistent in generic, unfertilized beech forest ecosystems of Germany, where differences in nutrient contents are mostly a result of the parental material and climatic conditions. We postulate that in such ecosystems nutrient effects are less pronounced due to the possibility of the soil microbiome to adapt to the corresponding conditions over decades and the vegetation acts as the major driver. To test this hypothesis, we investigated the bacterial community composition in five different German beech dominated forest soils, representing a natural gradient of total‐ and easily available mineral‐P. A community fingerprinting approach was performed using terminal‐Restriction Fragment Length Polymorphism analysis of the 16S rRNA gene, while abundance of bacteria was measured applying quantitative real‐time PCR. Bacterial communities at the five forest sites were distinctly separated, with strongest differences between the end‐members of the P‐gradient. However the majority of identified microbial groups (43%) were present at all sites, forming a core microbiome independent from the differences in soil chemical properties. Especially in the P‐deficient soil the abundance of unique bacterial groups was highly increased, indicating a special adaption of the community to P limitation at this site. In this regard Correspondence Analysis elucidated that exclusively soil pH significantly affected community composition at the investigated sites. In contrast soil C, N and P contents did mainly affect the overall abundance of bacteria.