Search Results (27)

Background/Objectives: The dietary fat supply might interact with the intestinal microbiota via different mechanisms. Research on this topic, however, remains scarce in cats. For this reason, the present study was conducted to evaluate the impact of the fat concentration and fatty acid profile in the diet on the fecal microbiota of healthy cats. Methods: A low-fat basal diet was fed to ten healthy adult cats. The diet was offered without or with the daily addition of 0.5 g or 1 g of sunflower oil, fish oil or lard per kg body weight of the cats, using a randomized cross-over design. Each feeding period lasted for 21 days, and the fecal samples were collected on the last days of each period. The fecal microbiota was analyzed by 16S rDNA sequencing. Additionally, microbial metabolites (short-chain fatty acids, lactate, ammonium, biogenic amines) were measured in the fecal samples. Results: The dietary treatment had no impact on the alpha-diversity of the fecal microbiota or on the relative abundance of bacterial phyla in the samples. Only a few changes were observed in the relative abundance of bacterial genera and the concentrations of microbial metabolites in the feces, probably being of minor physiological relevance. Conclusions: The balanced intestinal microbiota of cats seems to be relatively resistant to moderate variations in the dietary fat supply over a short feeding period. Longer-term treatments and higher dietary fat levels should be evaluated in future studies to further clarify the relevance of fat intake for the feline gut microbiome. Full article

Background/Objectives: The dietary fat concentration and fatty acid profile can influence various aspects of the feline organism. This study examined their effects on the urine composition, apparent nutrient digestibility, and selected blood variables. Methods: Ten healthy adult cats (46.6 ± 14.1 months old, initial body weight 4.99 ± 0.91 kg) received a low-fat basic diet with or without the addition of sunflower oil, fish oil, or lard in a randomized crossover design. The oil and lard were added to the daily amount of food at 0.5 or 1 g/kg body weight of the cats. At the end of each 3-week feeding period, urine, feces, and fasting blood samples were collected. Results: The results demonstrated only small effects of the dietary fat concentration and source on the urine composition of the cats. In addition, the apparent nutrient digestibility was unaffected by the dietary treatments. The supplementation with fish oil, but not sunflower oil or lard, lowered the triglycerides and increased the total and low-density lipoprotein cholesterol concentrations in the plasma of the cats (p < 0.05). However, these blood values were within the physiological reference ranges among all groups. Conclusions: It can be concluded that the dietary fat content and fatty acid profile did not adversely affect the urine composition or nutrient digestibility in healthy adult cats. The lipid metabolism of the animals was modulated by the supplementation with fish oil, a relevant source of n-3 fatty acids. The observed triglyceride-lowering effect should be further investigated in clinical studies. Full article

Background: Methionine (Met) is a popular nutritional supplement in humans and animals. It is routinely supplemented to pigs as L-Met, DL-Met, or DL-2-hydroxy-4-(methylthio) butanoic acid (DL-HMTBA). Methods: We investigated the effect of these Met supplements on jejunal amino acid (AA) transport in male castrated Piétrain × Danbred pigs, also including a non-supplemented group. The mucosal-to-serosal flux of ten [¹⁴C]-labeled AAs (L-glutamine, glycine, L-leucine, L-lysine, L-Met, L-serine, L-threonine, L-tryptophan, L-tyrosine and L-valine) was investigated at two concentrations (50 µM and 5 mM). Inhibition of apical uptake by mucosal L-Met was also measured for these AAs. The intestinal expression of apical AA transporters, angiotensin-converting enzyme II and inflammation-related genes were compared with those of a previous study. Results: Except for tryptophan and lysine at 5 mM, all AA fluxes were Na⁺-dependent (p ≤ 0.05), and the uptake of most AAs, except glycine and lysine, was inhibited by L-Met (p < 0.001). A correlation network existed between Na⁺-dependent fluxes of most AAs (except tryptophan and partly glycine). We observed the upregulation of B⁰AT1 (SLC6A19) (p < 0.001), the downregulation of ATB^0,+ (SLC6A14) (p < 0.001) and a lower expression of CASP1, IL1β, IL8, TGFβ and TNFα in the present vs. the previous study (p < 0.001). Conclusions: The correlating AAs likely share the same Na⁺-dependent transporter(s). A varying effect of the Met supplement type on AA transport in the two studies might be related to a different level of supplementation or a different inflammatory status of the small intestine. Full article

In natural ventilation system-enabled dairy buildings (NVDB), achieving accurate gas emission values is highly complicated. The external weather affects measurements of the gas concentration of pollutants ($c_P$) and volume flow rate (Q) due to the open-sided design. Previous research shows that increasing the number of sensors at the side opening is not cost-effective. However, accurate measurements can be achieved with fewer sensors if an optimal sampling position is identified. Therefore, this study attempted to calibrate the outlet of an NVDB for the direct emission measurement method. Our objective was to investigate the $c_P$ gradients, in particular, for ammonia ($c_{N{H}_3}$), carbon dioxide ($c_{C{O}_2}$), and methane ($c_{C{H}_4}$) considering the wind speed (v) and their mixing ratios ([$\overline{{\mathrm{c}}_{{\mathrm{CH}}_4}/{\mathrm{c}}_{{\mathrm{NH}}_3}}$]) at the outlet, and assess the effect of sampling height (H). The deviations in each $c_P$ at six vertical sampling points were recorded using a Fourier-transform infrared (FTIR) spectrometer. Additionally, wind direction and speed were recorded at the gable height (10 m) by an ultrasonic anemometer. The results indicated that, at varied heights, the average $c_{N{H}_3}$ (p < 0.001), $c_{C{O}_2}$ (p < 0.001), and (p < 0.001) were significantly different and mostly concentrated at the top (H = 2.7). Wind flow speed information revealed drastic deviations in $c_P$, for example up to $+105.1\%$ higher $c_{N{H}_3}$ at the top (H = 2.7) compared to the baseline (H = 0.6), especially during low wind speed (v < 3 m s${}^{-1}$) events. Furthermore, [$\overline{{\mathrm{c}}_{{\mathrm{CH}}_4}/{\mathrm{c}}_{{\mathrm{NH}}_3}}$] exhibited significant variation with height, demonstrating instability below 1.5 m, which aligns with the average height of a cow. In conclusion, the average $c_{C{O}_2}$, $c_{C{H}_4}$, and $c_{N{H}_3}$ measured at the barn’s outlet are spatially dispersed vertically which indicates a possibility of systematic error due to the sensor positioning effect. The outcomes of this study will be advantageous to locate a representative gas sampling position when measurements are limited to one constant height, for example using open-path lasers or low-cost devices. Full article

Little is known about the animal- and diet-related factors that could interfere with the plasma zinc (Zn) concentrations of equines. Additionally, the adequacy of plasma to reflect changes in the Zn intake is unclear. In the first part of this study, the plasma Zn concentrations of hospitalized horses and ponies (n = 538) were measured and evaluated for the impact of the age, sex, horse type, and internal diseases of the animals. In the second part, the effects of increasing dietary Zn chloride hydroxide and Zn methionine supplementations were assessed on the plasma and mane hair Zn concentrations of healthy horses (n = 2) and ponies (n = 8). Part 1: The age, sex, and horse type did not influence the plasma Zn concentrations. No effect of internal diseases was observed, with the exception of higher plasma Zn concentrations in animals with metabolic disorders compared to the control group (p < 0.05). Part 2: Both Zn supplements dose-dependently increased the Zn concentrations in the mane hair (p = 0.003), but not in the plasma of the horses and ponies. In conclusion, the plasma Zn concentrations were widely unaffected by nutritional and non-nutritional factors in equines, while mane hair samples better reflected the dietary Zn supply. Full article

Antibiotic resistance poses a risk for human and animal health, leading to a growing demand for effective alternatives. Combining nutritional tools and parent stock vaccination could be an approach to achieve sufficient protection against bacterial infections in poultry. In an Escherichia coli O1/O18 challenge trial, we investigated the protective effects of feeding diets containing Enterococcus faecium DSM 7134 and fructooligosaccharides (FOS) combined with specific parent stock vaccination in 225 ROSS 308 broilers. Data on performance parameters, intestinal microbial composition and metabolites, and antibiotic resistance genes (sul1-3, dhfr1a, SHV-12) were obtained. E. faecium and FOS combined with parent stock vaccination led to the highest body weights, which were significantly higher than those of controls throughout the experiment and decreased the relative abundance of Proteobacteria in the crop digesta compared to that in the positive control. However, cumulative feed conversation remained unaffected by the strategies. Birds receiving the pre-/probiotic combination showed lower cecal pH levels and higher crop L-lactate concentrations than the controls, whereas copy numbers of dhfr1a (trimethoprim resistance) and SHV-12 (extended-spectrum beta-lactamase) genes were only decreased in broilers from vaccinated hens compared to those in the challenged control. In conclusion, prophylactic administration of E. faecium and FOS in combination with parent stock vaccination can have complementary effects by improving broiler weight gain and stimulating intestinal bacterial metabolism, which may be beneficial for maintaining gut health in terms of Escherichia coli infection. Full article

Proteome analyses can be used to detect biomarkers for the healthy and diseased organism. However, data in cats are scarce, and no information is available on the potential impact of nutritional interventions on the feline urine proteome. In the present study, a label-free shotgun proteomics approach was performed to investigate the urinary proteins of four healthy adult cats. Each animal received a high-protein complete diet without (w/o) or with supplements that could affect the protein metabolism: arginine (+100% compared to the arginine concentration in the w/o diet), ornithine (+200% compared to the arginine concentration in the w/o diet) or zeolite (0.375 g/kg body weight/day). Our results demonstrate a huge number of proteins in the urine of cats (516 ± 49, 512 ± 39, 399 ± 149 and 455 ± 134 in the w/o, arginine, ornithine and zeolite group, respectively), which are associated with several biological processes. In addition, up- and downregulated urinary proteins could be detected in the dietary supplementation periods. Overall, the present pilot study provides basic data on the urine proteome of healthy adult cats. With increasing information, the numerousness of urinary proteins implies the potential to identify biomarkers and metabolic pathways in the feline organism. Full article

Mortality, impaired development and metabolic dysfunctions of suckling low-birthweight piglets may be influenced by modulating the intestinal microbiome through glutamine supplementation. Therefore, this study examined whether glutamine supplementation may affect the colonic development and microbiome composition of male low- and normal-birthweight piglets at 5 and 12 days of age. Suckling piglets were supplemented orally with glutamine or alanine. Colonic digesta samples were obtained for 16S rDNA sequencing, determination of bacterial metabolites and histomorphological tissue analyses. Glutamine-supplemented piglets had lower concentrations of cadaverine and spermidine in the colonic digesta (p < 0.05) and a higher number of CD3⁺ colonic intraepithelial lymphocytes compared to alanine-supplemented piglets (p < 0.05). Low-birthweight piglets were characterised by a lower relative abundance of Firmicutes, the genera Negativibacillus and Faecalibacterium and a higher abundance of Alistipes (p < 0.05). Concentrations of cadaverine and total biogenic amines (p < 0.05) and CD3⁺ intraepithelial lymphocytes (p < 0.05) were lower in low- compared with normal-birthweight piglets. In comparison to the factor age, glutamine supplementation and birthweight were associated with minor changes in microbial and histological characteristics of the colon, indicating that ontogenetic factors play a more important role in intestinal development. Full article

The supplementation of feed with phytases enables broilers to utilize more efficiently phosphorus (P) from phytic acid (IP₆), the main storage form of P in plants. The current study evaluated the addition of 500, 1000, and 3000 FTU of phytase per kg to a phytate-containing diet with low P level (LP) fed to broilers from 1 to 21 days of age and compared it to a hypoallergenic phytate-free diet (HPF). There was a linear improvement in performance parameters with increasing levels of phytase in the LP diet (p < 0.001). Apparent ileal digestibility of crude protein, P, and some amino acids, increased with phytase. Crude ash, P, and the calcium content of tibia bones linearly increased with increasing levels of phytase (p < 0.001). Crypt depth (related to body weight) in the jejunum epithelium linearly decreased with phytase addition (p < 0.001). Cecal crypt depth decreased with phytase supplementation (p = 0.002). Cecum tissue showed lower counts of CD3-positive intraepithelial lymphocytes in broilers receiving the phytase in comparison to LP (p < 0.001), achieving similar counts to HPF-fed broilers. Although results from the current study seem to point out some mechanisms related to the immune response and mucosal morphology contributing to those overall beneficial effects, no clear differences between different phytase doses could be demonstrated in these specific parameters. Full article

Lipids represent a significant energy source in dogs’ diets. Moreover, dogs need some essential fatty acids, such as linoleic and α-linolenic fatty acids, because they are not able to produce them endogenously. This study aimed to evaluate the effect of different dietary lipid sources on faecal microbial populations and activities using different evaluations. Hemp seed oil and swine tallow were tested as lipid supplements in a commercial canned diet at a ratio of 3.5% (HL1 and HL2, respectively). These diets were compared with one rich in starch (HS). Twelve dogs were recruited and equally divided into three groups. Faeces samples at 30 days were used as inoculum and incubated with three different substrates (MOS, inulin, and cellulose) using the in vitro gas production technique. The faecal cell numbers of relevant bacteria and secondary metabolites were analysed (in vivo trial). In vitro evaluation showed that the faeces of the group fed the diet with hemp supplementation had better fermentability despite lower gas production. The in vivo faecal bacterial count showed an increase in Lactobacillus spp. In the HL1 group. Moreover, a higher level of acetate was observed in both evaluations (in vitro and in vivo). These results seem to indicate a significant effect of the dietary fatty acid profile on the faecal microbial population. Full article

Feeding high-energy (HED) or high-fat diets during gestation and lactation to pigs may help cover the energy requirements of high-prolific sows but may also adversely affect their reproductive performance. The microalga Arthrospira plantensis (Sp), rich in bioactive compounds, has been described to exert beneficial health effects. The present study investigated the effects of HED and Sp intake during gestation and lactation in pigs. Twenty-four primiparous crossbred sows were fed either a HED or a control diet. Half of the sows per group were supplemented with 20 g/day of Sp. Despite a higher gross energy intake, consuming the HED did not affect the sows’ reproductive and lactational performance but significantly modified the colostrum fatty acid (FA) composition and tended to decrease the number of weaned piglets. The Sp supplementation did not affect the reproduction and lactation traits, but slightly affected the colostrum FA composition. A trend was observed for an interaction of diet and Sp in terms of offspring sex ratio with a 50% lower male-to-female ratio in the HED group compared to all other animals. These findings suggest that an HED and Sp intake hardly influence reproduction in sows. However, the HED modified the colostrum FA composition, whereas the Sp had only fewer effects, which may potentially affect offspring performance. Full article

Clostridioides difficile is an environmentally acquired, anaerobic, spore-forming bacterium which ordinarily causes disease following antibiotic-mediated dysbiosis of the intestinal microbiota. Although much is understood regarding the life cycle of C. difficile, the fate of C. difficile spores upon ingestion remains unclear, and the underlying factors that predispose an individual to colonization and subsequent development of C. difficile infection (CDI) are not fully understood. Here, we show that Bacillus, a ubiquitous and environmentally acquired, spore-forming bacterium is associated with colonization resistance to C. difficile. Using animal models, we first provide evidence that animals housed under conditions that mimic reduced environmental exposure have an increased susceptibility to CDI, correlating with a loss in Bacillus. Lipopeptide micelles (~10 nm) produced by some Bacilli isolated from the gastro-intestinal (GI)-tract and shown to have potent inhibitory activity to C. difficile have recently been reported. We show here that these micelles, that we refer to as heterogenous lipopeptide lytic micelles (HELMs), act synergistically with components present in the small intestine to augment inhibitory activity against C. difficile. Finally, we show that provision of HELM-producing Bacillus to microbiota-depleted animals suppresses C. difficile colonization thereby demonstrating the significant role played by Bacillus in colonization resistance. In the wider context, our study further demonstrates the importance of environmental microbes on susceptibility to pathogen colonization. Full article

Numerous bioactive plant additives have shown various positive effects in pigs and chickens. The demand for feed additives of natural origin has increased rapidly in recent years to support the health of farm animals and thus minimize the need for antibiotics and other drugs. Although only in vivo experiments can fully represent their effect on the organism, the establishment of reliable in vitro methods is becoming increasingly important in the goal of reducing the use of animals in experiments. The use of cell models requires strict control of the experimental conditions so that reliability and reproducibility can be achieved. In particular, the intestinal porcine epithelial cell line IPEC-J2 represents a promising model for the development of new additives. It offers the possibility to investigate antioxidative, antimicrobial, anti- or pro-proliferative and antiviral effects. However, the use of IPEC-J2 is limited due to its purely epithelial origin and some differences in its morphology and functionality compared to the in vivo situation. With regard to chickens, the development of a reliable intestinal epithelial cell model has attracted the attention of researchers in recent years. Although a promising model was presented lately, further studies are needed to enable the standardized use of a chicken cell line for testing phytogenic feed additives. Finally, co-cultivation of the currently available cell lines with other cell lines and the development of organoids will open up further application possibilities. Special emphasis was given to the IPEC-J2 cell model. Therefore, all publications that investigated plant derived compounds in this cell line were considered. The section on chicken cell lines is based on publications describing the development of chicken intestinal epithelial cell models. Full article

Feline diets can markedly differ in their protein concentration and quality, which might also affect the intestinal microbiota of cats. In the present study, 6 canned diets, differing in their protein quality (high/low, achieved by varying amounts of meat and collagen-rich ingredients) and concentration (high quality/low quality: 36.2/36.7% in dry matter (DM), 43.3/45.0% in DM and 54.9/56.1% in DM), were fed to 10 healthy adult cats for 6 weeks each. At the end of the feeding periods, fecal samples were collected to analyze the microbiota (16S rDNA sequencing) and bacterial metabolites. Increasing dietary protein concentrations increased the relative abundance of Fusobacterium and Bacteroides as well as the concentrations of ammonium and n-valerate in the feces of the cats, independently of the dietary protein quality. A lower dietary protein quality was accompanied by a higher evenness index and a higher relative abundance of Fusobacteria and Bacteroidetes in the feces when compared to the feeding of the high protein quality diets. A promotion of bacterial proteolytic activity and, in particular, increased intestinal ammonium concentrations might be undesired effects of high protein intakes in cats. Whether the long-term feeding of those diets could be critical for feline health requires further investigation. Full article

Due to the global spread of antibiotic resistance, there is a strong demand to replace antimicrobial growth promotors in livestock. To identify suitable additives that inhibit the growth of avian pathogenic Escherichia coli O1/O18 and Salmonella enterica serotype Enteritidis strains, an ex vivo screening was performed. Inulin and fructooligosaccharides (FOS) were investigated as prebiotics. Enterococcus faecium and Bacillus coagulans served as probiotic strains. Firstly, the pathogen was anaerobically incubated in caecal digesta from different broiler breeder flocks with the addition of feed additives. Secondly, subsamples of these suspensions were incubated in an antibiotic medium for selective growth of the pathogen. During this step, turbidity was recorded, and lag times were calculated for each pathogen as readout of growth inhibition. Combinations of E. faecium with inulin or FOS significantly extended the lag time for E. coli compared to control. Moreover, older age was a significant factor to enhance this inhibitory effect. In contrast, the combination of FOS and B. coagulans showed shorter lag times for S. Enteritidis. Our results indicate that the E. faecium strain with prebiotics may inhibit the pathogen proliferation in the studied poultry flocks. Furthermore, our results suggest that prophylactic treatments should be assigned by feed additive, age and animal origin. Full article