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Case Report of Puffinosis in a Manx Shearwater (Puffinus puffinus) Suggesting Environmental Aetiology
No full textPuffinosis is a disease of a range of seabirds characterised by dorsal and ventral blistering of their webbed feet, conjunctivitis, dry necrosis, leg spasticity, head shaking, loss of balance, tremors, and death. It is associated with Manx shearwaters (Puffinus puffinus), frequently affecting chicks within their underground nesting burrows. The aetiology of the disease is unclear but has been attributed to a type-2 coronavirus associated with Neotombicula mites as a potential vector. However, there is some uncertainty given potential laboratory contamination with mouse hepatitis virus and failure to fulfil Koch’s postulates, with birds injected with isolates remaining healthy. We describe a detailed case report of puffinosis in a Manx Shearwater covering necropsy, histology, bacteriology, and metagenomics including viral sequencing. We found no evidence of viral infection or parasites. Our results are consistent with an entirely environmental aetiology, with caustic faecal ammonia in damp nesting burrows causing conjunctivitis and foot dermatitis breaking the skin, allowing common soil bacteria (i.e., Flavobacterium, Staphylococcus and Serratia spp., Clostridia perfringens and Enterococcus faecalis) to cause opportunistic infection, debilitating the bird and leading to death. A similar condition (foot pad dermatitis or FPD) has been reported in broiler chickens, attributed to caustic faeces, high humidity, and poor environmental conditions during indoor rearing, preventable by adequate ventilation and husbandry. This is consistent with puffinosis being observed in Shearwater nesting burrows situated in tall, dense, vegetation (e.g., bracken Pteridium aquilinum) but rarely reported in burrows situated in well-ventilated, short coastal grasslands. This proposed environmental aetiology accounts for the disease’s non-epizootic prevalence, spatial variation within colonies, and higher frequency in chicks that are restricted to nesting burrows
A Microsimulation Model for the Land Rental Market in Irish Farming
Get PDFpeer-reviewedIn this paper, we utilize Teagasc National Farm survey data to analyse the agricultural land rental market in Ireland with a newly developed agent-based microsimulation (ABM) model and a classical walrasian equilibrium model of the land rental market. We conclude that the microsimulation model has a number of strengths in addressing the interactions between landowners and tenants and dealing with the impact of economic changes on the farm size concentration. The equilibrium model retains some value in dealing with the question of price determination and in illustrating the potential surpluses to be gained from a more active land rental market. The paper contains a comparison of simulation results from the ABM model with recent farm-level data and Census of Agriculture data. These comparisons indicate the relevance of some findings from the simulation model including the rise in average dairy farm size and the decline in area allocated to non-dairy cattle farming. However, the sheep farming system appears to have defied the predictions from the simulation model and this may be attributed to the recent improvement in economic performance for this sector. The ABM model can be further refined to account for decisions in relation to the choice of farming system, the question of retirement and farm exit
Blood and faecal biomarkers to assess dietary energy, protein and amino acid efficiency of utilization by growing and finishing pigs
Get PDFpeer-reviewedBackground
Diet evaluation and optimization is a slow and expensive process and it is not possible to do it at a farm level. This study aimed to use the blood serum metabolite (BSM) and faecal volatile fatty acid (VFA) profiles as potential biomarkers to identify changes in protein, amino acid and energy dietary content in growing and finishing pig diets at farm level.
Results
Two studies were conducted. The first study (S1) included 20 pens of 11 pigs (87.0 ± 4.10 kg; 18 weeks old) assigned to 5 diets: control (C1), high or low crude protein (HP1 and LP1, respectively), and high or low net energy (HE1 and LE1, respectively). The second study (S2) included 28 pens of 11 pigs (41.3 ± 2.60 kg; 12 weeks old) assigned to 7 diets: control (C2), high or low crude protein (HP2 and LP2, respectively), high or low amino acid (HA2 and LA2, respectively), and high or low net energy (HE2 and LE2, respectively). Pigs were followed for 10 (S1) and 20 (S2) days, and blood and faecal samples were collected at 20 (S1) and 14 (S2) weeks of age. Data were analysed using general linear models and receiver operating characteristic curve analysis. Urea nitrogen showed the best results as a biomarker. Urea nitrogen was higher in pigs fed high protein diets, HP1 (13.6 ± 0.95 mg/dL) and HP2 (11.6 ± 0.61), compared to those fed low protein diets, LP1 (6.0 ± 0.95) and LP2 (5.2 ± 0.61; P 0.05; AUC = 71.9%), which were formulated based on the ideal protein profile but with no excess of protein. Creatinine, triglycerides, branched-chain fatty acids, albumin, propionic acid, and cholesterol showed differences between at least 2 diets but only in one of the studies.
Conclusions
Urea nitrogen showed high accuracy to detect excess of crude protein in growing and finishing pig diets. Other biomarkers like BCFA showed promising results and need to be further studied
The type of gum arabic affects interactions with soluble pea protein in complex coacervation
Get PDFpeer-reviewedComplex coacervation is an encapsulation process involving two oppositely charged biopolymers. Since different compositions of gum arabic may affect its interaction with protein, we studied the complex coacervation of two types of gum arabic (GA) (Acacia senegal-GA1 and Acacia seyal-GA2) with soluble pea protein (SPP) through Zeta potential, turbidity, morphology, the secondary structure of SPP, UV/vis absorbance and thermodynamic parameters. The maximum formation of coacervates occurred at SPP:GA 3:1 (w/w) and pH 3.5–4.0 with changes in the secondary structure of SPP. GA1 combination resulted in higher binding constant, implying a stronger affinity between SPP and GA1. Entropy of 0.7 and 0.5 kJ/mol.K, and enthalpy of −151 and −95.5 kJ/mol were obtained for SPP:GA1 and SPP:GA2. The complex coacervation was spontaneous as proved by the negative values of the Gibbs free energy. GA1 resulted in stronger interactions with SPP, offering new alternatives for encapsulation of bioactive compounds.TEAGAS
The Prebiotic Effect of Australian Seaweeds on Commensal Bacteria and Short Chain Fatty Acid Production in a Simulated Gut Model
Get PDFpeer-reviewedDiet is known to affect the composition and metabolite production of the human gut microbial community, which in turn is linked with the health and immune status of the host. Whole seaweeds (WH) and their extracts contain prebiotic components such as polysaccharides (PS) and polyphenols (PP). In this study, the Australian seaweeds, Phyllospora comosa, Ecklonia radiata, Ulva ohnoi, and their PS and PP extracts were assessed for potential prebiotic activities using an in vitro gut model that included fresh human faecal inoculum. 16S rRNA sequencing post gut simulation treatment revealed that the abundance of several taxa of commensal bacteria within the phylum Firmicutes linked with short chain fatty acid (SCFA) production, and gut and immune function, including the lactic acid producing order Lactobacillales and the chief butyrate-producing genera Faecalibacteria, Roseburia, Blautia, and Butyricicoccus were significantly enhanced by the inclusion of WH, PS and PP extracts. After 24 h fermentation, the abundance of total Firmicutes ranged from 57.35–81.55% in the WH, PS and PP samples, which was significantly greater (p ≤ 0.01) than the inulin (INU) polysaccharide control (32.50%) and the epigallocatechingallate (EGCG) polyphenol control (67.13%); with the exception of P. comosa PP (57.35%), which was significantly greater than INU only. However, all WH, PS and PP samples also increased the abundance of the phylum Proteobacteria; while the abundance of the phylum Actinobacteria was decreased by WH and PS samples. After 24 h incubation, the total and individual SCFAs present, including butyric, acetic and propionic acids produced by bacteria fermented with E. radiata and U. ohnoi, were significantly greater than the SCFAs identified in the INU and EGCG controls. Most notably, total SCFAs in the E. radiata PS and U. ohnoi WH samples were 227.53 and 208.68 µmol/mL, respectively, compared to only 71.05 µmol/mL in INU and 7.76 µmol/mL in the EGCG samples. This study demonstrates that whole seaweeds and their extracts have potential as functional food ingredients to support normal gut and immune function
Extraction of plant protein from green leaves: Biomass composition and processing considerations
Get PDFpeer-reviewedThere is an increasing need to explore alternative sources of proteins for food applications. Green leaves contain high levels of the enzyme RuBisCO, representing a source of protein with good functional and nutritional properties. However, the optimal conditions for extraction and purification of RuBisCO at a large scale have not yet been defined. This review discusses the main factors affecting the extraction of proteins from green leaves, from plant composition in terms of protein content and other compounds that affect the yield and quality of extractable protein, to the essential steps and challenges faced during extraction and purification, including considerations for achieving food-grade ingredient status. There are some key factors to consider when developing a protein concentrate for human consumption. The first step is the selection of an optimal raw material; plant tissues are complex matrices that require thorough characterization, including non-protein nitrogen and other undesirable compounds. The effect of the extraction and purification process on functionality, oxidation and proteolytic stability should also be considered. Moreover, the appropriate removal of undesired compounds must be considered to obtain plant protein concentrates suitable for food products
Polysaccharides and polyphenols derived from Australian seaweeds enhance microbial abundance and short chain fatty acid production in a simulated gut-model
No full textBackground: Diet is known to affect the composition of the human gut microbiota and bacterial production of short chain fatty acids (SCFA), which impacts the overall health of the host.
Whole seaweeds (WH) contain prebiotic components such as polysaccharides (PS) and polyphenols (PP) that can be digested by gut bacteria. Method: WH, PS and PP extracts from Phyllospora comosa, Ecklonia radiata and Ulva ohnoi, harvested in Australia, were assessed for their potential prebiotic activities using an in vitro model with human faecal inoculum. The relative abundance of bacteria was determined by 16S rRNA sequencing. SCFA were quantified by gas chromatography. Results: After 24 hr, compared to the inulin (INU) and epigallocatechingallate (EGCG) controls,
WH, PS and PP extracts significantly enhanced the abundance of bacterial taxa positively associated with SCFA production, microbiota homeostasis, gut mucosal barrier regulation,
immunity and anti-inflammatory effects. These included Lactobacillales, Bifidobacteriaceae, Eggerthellaceae, Faecalibacteria, Blautia and Barnesiella. The Firmicutes/Bacteroidetes ratio,
as well as species diversity and richness were increased by all seaweed extracts. Seaweeds increased total and individual SCFA production up to three-fold, particularly butyrate, acetate
and propionate. Conclusions: Seaweeds and their extracts may have potential as prebiotic functional foods to maintain normal gut function and alleviate dysbiosis
Enhancing early life nutrition alters the hepatic transcriptome of Angus × Holstein-Friesian heifer calves
Get PDFpeer-reviewedEarly life nutrition has a major influence on subsequent lifetime performance in cattle. The aim of this experiment was to investigate the effect of plane of nutrition from 3 to 21 weeks of age on the liver transcriptome. Holstein-Friesian × Angus heifer calves with a mean (±SD) age and BW of 19 (±5) days and 51.2 (±7.8) kg, respectively, were assigned to either a high-energy diet to support a mean average daily gain (ADG) of 1.2 kg/day (HI; n = 15) or a moderate diet (MOD; n = 15) to support a mean ADG of 0.5 kg/day. At 145 ± 3 days of age, all calves were euthanised, liver tissue samples collected and flash-frozen in liquid nitrogen. Following RNA sequence analysis, the total number of differentially expressed genes (DEGs) (at false discovery rate (FDR) > 0.05) was 537; 308 upregulated and 229 downregulated in HI compared to MOD. The number of DEGs mapped to IPA (at FDR > 0.05) was 460; 264 upregulated and 196 downregulated. There was greater expression of genes associated with cellular development and metabolism in heifers on the HI compared to the MOD diet. The genes (fold change) of the somatotrophic axis; IGF1 (3.7), IGFALS (2.6) and GHR (1.5) were upregulated in the HI compared to MOD diet. The cytokine receptor genes, IL17RB (1.7) and IL20RA (3.3), were upregulated in the HI heifers, which were detected in a network interacting with metabolically regulated genes. The potential enhanced cell-to-cell communication evident from DEGs would increase the calves’ ability to combat health challenges. The findings of this study indicate that enhancing the early life plane of nutrition in heifer calves results in the upregulation of genes that are associated with increased metabolic activity and thus metabolic capacity. Moreover, the interaction between metabolic and immune communication genes indicates that enhanced nutrition has the potential to improve the immune response in the liver which will play a central role in ensuring optimal lifetime performance
Analysis of the effect of Bacillus velezensis culture filtrate on the growth and proteome of Cladobotryum mycophilum
Get PDFpeer-reviewedCladobotryum mycophilum, the causative agent of cobweb disease on Agaricus bisporus results in significant crop losses for mushroom growers worldwide. Cobweb disease is treated through strict hygiene control methods and the application of chemical fungicides but an increase in fungicide resistant Cladobotryum strains has resulted in a need to develop alternative biocontrol treatment methods. The aim of the work presented here was to evaluate the response of C. mycophilum to a Bacillus velezensis isolate to assess its potential as a novel biocontrol agent. Exposure of 48 hr C. mycophilum cultures to 25% v/v 96 hr B. velezensis culture filtrate resulted in a 57% reduction in biomass (P < 0.0002), a disruption in hyphal structure and morphology, and the appearance of aurofusarin, a secondary metabolite which is a known indicator of oxidative stress, in culture medium. Proteomic analysis of B. velezensis culture filtrate revealed the presence of peptidase 8 (subtilisin), peptide deformylase and probable cytosol aminopeptidase which are known to induce catalytic activity. Characterisation of the proteomic response of C. mycophilum following exposure to B. velezensis culture filtrate revealed an increase in the abundance of a variety of proteins associated with stress response (ISWI chromatin-remodelling complex ATPase ISW2 (+24 fold), carboxypeptidase Y precursor (+3 fold) and calmodulin (+2 fold). There was also a decrease in the abundance of proteins associated with transcription (40 S ribosomal protein S30 (−26 fold), 40 S ribosomal protein S21 (−3 fold) and carbohydrate metabolism (l-xylulose reductase (−10 fold). The results presented here indicate that B. velezensis culture filtrate is capable of inhibiting the growth of C. mycophilum and inducing a stress response, thus indicating its potential to control this important pathogen of mushrooms
Food neophobia and its relationship with dietary variety and quality in Irish adults: Findings from a national cross-sectional study
Get PDFpeer-reviewedFood neophobia is characterised by a reluctance to eat novel or unfamiliar foods and has been linked to reduced dietary variety and quality. However, this link has been primarily studied in children. Therefore, we aimed to explore the relationship between food neophobia and dietary variety and quality in adults using a sub-sample of the National Adults Nutrition Survey collected between 2008 and 2010 (n = 1088). Food and nutrient intakes were assessed using a 4-day semi-weighed food diary. Food neophobia was measured using the Food Neophobia Scale (FNS). Dietary variety was assessed in three ways; Total Dietary Variety (TDV), Food-Group Variety (FGV) and Fruit and Vegetable Variety (FVV). Diet quality was assessed using the Mean Adequacy Ratio (MAR) and Nutrient-Rich Food Index (NRF9.3). A multivariate general linear model was used to assess the linear relationships between FNS score and all dietary measures, controlling for age, sex, education level, social class, location and BMI. Food neophobia was found to be inversely associated with TDV, FGV and FVV. In addition, food neophobia was negatively associated with vitamin C, magnesium and fruit and vegetable intakes and positively associated with percentage energy from free sugars. However, food neophobia was not significantly associated with all other nutrients, MAR and NRF9.3. While these results suggest food neophobia may not be a particularly important risk factor for poor nutrient status, adherence to certain dietary recommendations remains low within the Irish population and food neophobia may further inhibit the adaption of healthy and sustainable diets. Future research should seek to understand the implications of food neophobia on dietary behaviour change