Multispecies pasture diet and cow breed impacts on milk composition and quality in a seasonal spring-calving dairy production system.

In recent years, there has been significant emphasis on the composition of pasture-based cow feed and the potential benefits of incorporating multispecies swards to improve sustainability and biodiversity. This study compared the effects of a conventional perennial ryegrass (PRG) monoculture supported by high chemical nitrogen (N) usage with a low chemical N application multispecies sward system (MSS) on the composition and quality of milk across lactation using spring-calving Holstein-Friesian (HF) and Jersey Holstein-Friesian (JFX) cows. Bulk milk samples (n = 144) were collected from each group at morning and evening milking on a weekly basis (n = 36) throughout lactation and analyzed for gross composition and physico-chemical properties. Cow breed had a significant impact on milk profile, with milk from HF cows having significantly smaller milk fat globule (MFG) size, higher instability index values, higher yield, and lower total solids levels, compared with JFX cows. Notably, HF cows had increased milk total solids and fat levels when fed on MSS, as opposed to the PRG-fed HF cows. Feeding MSS pasture increased creaming velocity values in mid and late lactation, and resulted in similar milk gross composition to PRG. In comparison to PRG, MSS-fed groups showed significantly increased total solids yield, including higher levels of protein and fat yield. In late lactation, MSS feeding was associated with reduced MFG size. All physicochemical properties studied (MFG size, creaming velocity, instability index) showed decreasing values from early to late lactation stage. Overall, these findings demonstrate the significant effects of cow diet, breed and stage of lactation on compositional and physico-chemical characteristics of milk, with important implications for milk processing and dairy product quality.

Infant milk formula, produced by membrane filtration, promotes mucus production in the upper small intestine of young pigs.

Human breast milk promotes maturation of the infant gastrointestinal barrier, including the promotion of mucus production. In the quest to produce next generation infant milk formula (IMF), we have produced IMF by membrane filtration (MEM-IMF). With a higher quantity of native whey protein, MEM-IMF more closely mimics human breast milk than IMF produced using conventional heat treatment (HT-IMF). After a 4-week dietary intervention in young pigs, animals fed a MEM-IMF diet had a higher number of goblet cells, acidic mucus and mucin-2 in the jejunum compared to pigs fed HT-IMF (P < 0.05). In the duodenum, MEM-IMF fed pigs had increased trypsin activity in the gut lumen, increased mRNA transcript levels of claudin 1 in the mucosal scrapings and increased lactase activity in brush border membrane vesicles than those pigs fed HT-IMF (P < 0.05). In conclusion, MEM-IMF is superior to HT-IMF in the promotion of mucus production in the young gut.

Impact of varying levels of pasture allowance on the nutritional quality and functionality of milk throughout lactation.

The objective of this study was to examine the impact of increasing proportions of grazed pasture in the diet on the composition, quality, and functionality of bovine milk across a full lactation. Fifty-four spring-calving cows were randomly assigned to 1 of 3 groups (n = 18), blocked on the basis of mean calving date (February 15, 2020 ± 0.8 d), pre-experimental daily milk yield (24.70 ± 3.70 kg), milk solids yield (2.30 ± 0.27 kg), lactation number (3.10 ± 0.13), and economic breeding index (182 ± 19). Raw milk samples were obtained weekly from each group between March and November 2020. Group 1 (GRS) consumed perennial ryegrass and was supplemented with 5% concentrates (dry matter basis); group 2 was maintained indoors and consumed a total mixed ration (TMR) diet consisting of maize silage, grass silage, and concentrates; and group 3 consumed a partial mixed ration diet (PMR), rotating between perennial ryegrass during the day and indoor TMR feeding at night. Raw milk samples consisted of a pooled morning and evening milking and were analyzed for gross composition, free amino acids, fatty acid composition, heat coagulation time, color, fat globule size, and pH. The TMR milks had a significantly higher total solids, lactose, protein, and whey protein as a proportion of protein content compared with both GRS and PMR milks. The GRS milks demonstrated a significantly lower somatic cell count (SCC), but a significantly higher pH and b*-value than both TMR and PMR milks. The PMR milks exhibited significantly lower total solids and fat content, but also demonstrated significantly higher SCC and total free amino acid content compared with GRS and TMR. Partial least squares discriminant analysis of fatty acid profiles displayed a distinct separation between GRS and TMR samples, while PMR displayed an overlap between both GRS and TMR groupings. Variable importance in projection analysis identified conjugated linoleic acid cis-9,trans-11, C18:2n-6 cis, C18:3n-3, C11:0, and C18:2n-6 trans as the largest contributors to the variation between the diets. Milk fats derived from GRS diets exhibited the highest proportion of unsaturated fats and higher unsaturation, health-promoting, and desaturase indices. The lowest proportions of saturated fats and the lowest atherogenic index were also exhibited by GRS-derived milk fats. This work highlights the positive influence of grass-fed milk for human consumption through its more nutritionally beneficial fatty acid profile, despite the highest milk solid percentages derived from TMR feeding systems. Furthermore, this study demonstrates the proportional response of previously highlighted biomarkers of pasture feeding to the proportion of pasture in the cow's diet.

Isolation and identification of chlorate-reducing Hafnia sp. from milk.

Chlorate has become a concern in the food and beverage sector, related to chlorine sanitizers in industrial food production and water treatment. It is of particular concern to regulatory bodies due to the negative health effects of chlorate exposure. This study investigated the fate of chlorate in raw milk and isolated bacterial strains of interest responsible for chlorate breakdown. Unpasteurized milk was demonstrated to have a chlorate-reducing capacity, breaking down enriched chlorate to undetectable levels in 11 days. Further enrichment and isolation using conditions specific to chlorate-reducing bacteria successfully isolated three distinct strains of Hafnia paralvei. Chlorate-reducing bacteria were observed to grow in a chlorate-enriched medium with lactate as an electron donor. All isolated strains were demonstrated to reduce chlorate in liquid medium; however, the exact mechanism of chlorate degradation was not definitively identified in this study.

Draft Genome Sequences of Bacillus licheniformis and Bacillus paralicheniformis Strains Isolated from Irish Skim Milk Powder.

Nineteen Bacillus licheniformis strains and four strains of the closely related species Bacillus paralicheniformis were isolated from a variety of Irish medium-heat skim milk powders. The draft genome sequences of these 23 isolates provide valuable genetic data for research work relevant to dairy products and process development. The isolates are available at Teagasc.

The Protein Composition and In Vitro Digestive Characteristics of Animal- versus Plant-Based Infant Nutritional Products.

The protein composition and digestive characteristics of four commercially available infant formulae (IF) manufactured using bovine (B-IF), caprine (C-IF), soy (S-IF), and rice (R-IF) as a protein source were examined in this study. Plant-based formulae had significantly higher crude protein and non-protein nitrogen (NPN) concentrations. Static in vitro gastrointestinal digestion of these formulae, and subsequent analysis of their digestates, revealed significantly higher proteolysis of B-IF at the end of gastrointestinal digestion compared to the other formulae, as indicated by the significantly higher concentration of free amine groups. Furthermore, differences in structure formation during the gastric phase of digestion were observed, with formation of a more continuous, firmer coagulum by C-IF, while R-IF demonstrated no curd formation likely due to the extensive hydrolysis of these proteins during manufacture. Differences in digestive characteristics between formulae manufactured from these different protein sources may influence the bio-accessibility and bioavailability of nutrients, warranting additional study.

Deuterium-enriched water ties planet-forming disks to comets and protostars.

Water is a fundamental molecule in the star and planet formation process, essential for catalysing the growth of solid material and the formation of planetesimals within disks1,2. However, the water snowline and the HDO:H2O ratio within proto-planetary disks have not been well characterized because water only sublimates at roughly 160 K (ref. 3), meaning that most water is frozen out onto dust grains and that the water snowline radii are less than 10 AU (astronomical units)4,5. The sun-like protostar V883 Ori (M* = 1.3 M⊙)6 is undergoing an accretion burst7, increasing its luminosity to roughly 200 L⊙ (ref. 8), and previous observations suggested that its water snowline is 40-120 AU in radius6,9,10. Here we report the direct detection of gas phase water (HDO and [Formula: see text]) from the disk of V883 Ori. We measure a midplane water snowline radius of approximately 80 AU, comparable to the scale of the Kuiper Belt, and detect water out to a radius of roughly 160 AU. We then measure the HDO:H2O ratio of the disk to be (2.26 ± 0.63) × 10-3. This ratio is comparable to those of protostellar envelopes and comets, and exceeds that of Earth's oceans by 3.1σ. We conclude that disks directly inherit water from the star-forming cloud and this water becomes incorporated into large icy bodies, such as comets, without substantial chemical alteration.

Membrane filtration processing of infant milk formula alters protein digestion in young pigs.

Reducing heat treatment (HT) during processing of infant milk formula (IMF) is desirable to produce a product that more closely resembles breast milk. By employing membrane filtration (MEM), we produced an IMF (60:40 whey to casein ratio) at pilot scale (250 kg). MEM-IMF had a significantly higher content of native whey (59.9 %) compared to HT-IMF (4.5 %) (p < 0.001). Pigs, at 28 days old, were blocked by sex, weight and litter origin and assigned to one of two treatments (n = 14/treatment): (1) starter diet containing 35 % of HT-IMF powder or (2) starter diet containing 35 % of MEM-IMF powder for 28 days. Body weight and feed intake were recorded weekly. Pigs at day 28 post weaning were sacrificed 180 min after their final feeding, for the collection of gastric, duodenal, jejunum and ileal contents (n = 10/treatment). MEM-IMF diet resulted in more water-soluble proteins and higher levels of protein hydrolysis in the digesta at various gut locations compared to HT-IMF (p < 0.05). In the jejunal digesta, a higher concentration of free amino acids were present post MEM-IMF consumption (247 ± 15 µmol g-1 of protein in digesta) compared to HT-IMF (205 ± 21 µmol g-1 of protein). Overall, average daily weight gain, average dairy feed intake and feed conversion efficiency were similar for pigs fed either MEM-IMF or HT-IMF diets, but differences and trends to difference of these indicators were determined in particular intervention periods. In conclusion, reducing heat treatment during processing of IMF influenced protein digestion and revealed minor effects on growth parameters providing in vivo evidence that babies who are fed with IMF processed by MEM are likely to have different protein digestion kinetics but minimal effect on overall growth trajectories as babies fed IMF processed by traditional thermal processing.

Whole-cell vaccine candidates induce a protective response against virulent Acinetobacter baumannii.

Acinetobacter baumannii causes multi-system diseases in both nosocomial settings and a pre-disposed general population. The bacterium is not only desiccation-resistant but also notoriously resistant to multiple antibiotics and drugs of last resort including carbapenem, colistin, and sulbactam. The World Health Organization has categorized carbapenem-resistant A. baumannii at the top of its critical pathogen list in a bid to direct urgent countermeasure development. Several early-stage vaccines have shown a range of efficacies in healthy mice, but no vaccine candidates have advanced into clinical trials. Herein, we report our findings that both an ionizing γ-radiation-inactivated and a non-ionizing ultraviolet C-inactivated whole-cell vaccine candidate protects neutropenic mice from pulmonary challenge with virulent AB5075, a particularly pathogenic isolate. In addition, we demonstrate that a humoral response is sufficient for this protection via the passive immunization of neutropenic mice.

Superprotonic conduction of intrinsically zwitterionic microporous polymers based on easy-to-make squaraine, croconaine and rhodizaine dyes.

Porous organic polymers (POPs) have been prepared via a novel metal free polycondensation between a tritopic indole-based monomer and squaric, croconic and rhodizonic acids. Each of the three POPs exhibited high BET surface areas (331-667 m2 g-1) and zwitterionic structures. Impedance measurements revealed that the intrinsic POPs were relatively weak proton conductors, with a positive correlation between the density of oxo-groups and the proton conduction. Doping the materials with LiCl vastly improved the proton conductivity up to a value of 0.54 S cm-1 at 90 °C and 90% relative humidity.

Comparison of conventional heat-treated and membrane filtered infant formulas using an in vitro semi-dynamic digestion method.

Introducing membrane filtration steps into infant milk formula (IMF) manufacture can partly preserve native whey proteins in the final products. In this study, the IMF produced by membrane filtration (MEM-IMF) and conventional heat treatment (HT-IMF) were compared by using a novel semi-dynamic infant in vitro digestion method. MEM-IMF exhibited a fragmented curd during gastric digestion, and confocal laser light microscopy showed that protein aggregates had disassociated from the fat droplets within 93 min in the MEM-IMF digesta. In contrast, the digesta of HT-IMF showed a more extensive curd formation and denser protein aggregates, which remained intact until the end of gastric digestion. Molecular weight profiles and the primary amine assay suggested that protein degradation and peptide release were faster in the MEM-IMF. In conclusion, the presence of native whey protein in the IMF altered the gastric digestion kinetics by changing coagulation and formation of aggregates, potentially accelerating the rate of gastric emptying in vivo.

Select Whole-Cell Biofilm-Based Immunogens Protect against a Virulent Staphylococcus Isolate in a Stringent Implant Model of Infection.

Many microbes of concern to human health remain without vaccines. We have developed a whole-microbe inactivation technology that enables us to rapidly inactivate large quantities of a pathogen while retaining epitopes that were destroyed by previous inactivation methods. The method that we call UVC-MDP inactivation can be used to make whole-cell vaccines with increased potency. We and others are exploring the possibility of using improved irradiation-inactivation technologies to develop whole-cell vaccines for numerous antibiotic-resistant microbes. Here, we apply UVC-MDP to produce candidate MRSA vaccines which we test in a stringent tibia implant model of infection challenged with a virulent MSRA strain. We report high levels of clearance in the model and observe a pattern of protection that correlates with the immunogen protein profile used for vaccination.

Medical interventions for children born with variations in their sex characteristics: what's the rights approach?

There have been growing calls within Australia and beyond to defer medical interventions for children born with variations in their sex characteristics. These calls are increasingly grounded in the claim that such interventions when performed on infants and young children are a violation of their human rights. This paper examines the basis for this claim. It also examines the differences between the principles-based approach to medical ethics which has tended to dominant decisions regarding the treatment of children born with variations in their sex characteristics, relative to the adoption of a rights-based approach. It identifies the points of complementarity between these two discourses but suggests that a rights-based approach offers some unique and differing insights into several issues concerning children born with variations in their sex characteristics.

Prevalence and phenotype associations of complement factor I mutations in geographic atrophy.

Rare variants in the complement factor I (CFI) gene, associated with low serum factor I (FI) levels, are strong risk factors for developing the advanced stages of age-related macular degeneration (AMD). No studies have been undertaken on the prevalence of disease-causing CFI mutations in patients with geographic atrophy (GA) secondary to AMD. A multicenter, cross-sectional, noninterventional study was undertaken to identify the prevalence of pathogenic rare CFI gene variants in an unselected cohort of patients with GA and low FI levels. A genotype-phenotype study was performed. Four hundred and sixty-eight patients with GA secondary to AMD were recruited to the study, and 19.4% (n = 91) demonstrated a low serum FI concentration (below 15.6 µg/ml). CFI gene sequencing on these patients resulted in the detection of rare CFI variants in 4.7% (n = 22) of recruited patients. The prevalence of CFI variants in patients with low serum FI levels and GA was 25%. Of the total patients recruited, 3.2% (n = 15) expressed a CFI variant classified as pathogenic or likely pathogenic. The presence of reticular pseudodrusen was detected in all patients with pathogenic CFI gene variants. Patients with pathogenic CFI gene variants and low serum FI levels might be suitable for FI supplementation in therapeutic trials.

Control Over the Morphology of Electrospun Microfibrous Mats of a Polymer of Intrinsic Microporosity.

This study reports for the first time the preparation of an electrospun microfibrous mat of PIM-EA-TB. The electrospinning was carried out using a chloroform/n-Propyl-lactate (n-PL) binary solvent system with different chloroform/nPL ratios, in order to control the morphology of the microfibres. With pure chloroform, porous and dumbbell shape fibres were obtained whereas, with the addition on n-PL, circular and thinner fibres have been produced due to the higher boiling point and the higher conductivity of n-PL. The electrospinning process conditions were investigated to evaluate their impact on the fibres' morphology. These microfibrous mats presented potential to be used as breathable/waterproof materials, with a pore diameter of 11 µm, an air resistance of 25.10-7 m-1 and water breakthrough pressure of 50 mBar.

The Impact of Seasonality in Pasture-Based Production Systems on Milk Composition and Functionality.

Seasonal calving, pasture-based dairy systems are widely practiced in countries with a temperate climate and plentiful rainfall such as Ireland and New Zealand. This approach maximizes milk production from pasture and, consequently, is a low-cost, low-input dairy production system. On the other hand, the majority of global milk supply is derived from high input indoor total mixed ration systems where seasonal calving is not practiced due to the dependence on ensiled silages, grains and concentrated feeds, which are available year-round. Synchronous changes in the macro and micronutrients in milk are much more noticeable as lactation progresses through early, mid and late stages in seasonal systems compared to non-seasonal systems-which can have implications on the processability and functionality of milk.

Interfacial properties of milk proteins: A review.

The interfacial properties of dairy proteins are of great interest to the food industry. Food manufacturing involves various environmental conditions and multiple processes that significantly alter the structure and colloidal stability of food materials. The effects of concentration, pH, heat treatment, addition of salts etc., have considerable influence on the surface activity of proteins and the mechanical properties of the interfacial protein films. Studies to date have established some understanding of the links between environmental and processing related parameters and their impacts on interfacial behavior. Improvement in knowledge may allow better design of interfacial protein structures for different food applications. This review examines the effects of environmental and processing conditions on the interfacial properties of dairy proteins with emphasis on interfacial tension dynamics, dilatational and surface shear rheological properties. The most commonly used surface analytical techniques along with relevant methods are also addressed.

Radiation-Inactivated Acinetobacter baumannii Vaccine Candidates.

Acinetobacter baumannii is a bacterial pathogen that is often multidrug-resistant (MDR) and causes a range of life-threatening illnesses, including pneumonia, septicemia, and wound infections. Some antibiotic treatments can reduce mortality if dosed early enough before an infection progresses, but there are few other treatment options when it comes to MDR-infection. Although several prophylactic strategies have been assessed, no vaccine candidates have advanced to clinical trials or have been approved. Herein, we rapidly produced protective whole-cell immunogens from planktonic and biofilm-like cultures of A. baumannii, strain AB5075 grown using a variety of methods. After selecting a panel of five cultures based on distinct protein profiles, replicative activity was extinguished by exposure to 10 kGy gamma radiation in the presence of a Deinococcus antioxidant complex composed of manganous (Mn2+) ions, a decapeptide, and orthophosphate. Mn2+ antioxidants prevent hydroxylation and carbonylation of irradiated proteins, but do not protect nucleic acids, yielding replication-deficient immunogenic A. baumannii vaccine candidates. Mice were immunized and boosted twice with 1.0 × 107 irradiated bacterial cells and then challenged intranasally with AB5075 using two mouse models. Planktonic cultures grown for 16 h in rich media and biofilm cultures grown in static cultures underneath minimal (M9) media stimulated immunity that led to 80-100% protection.

Monitoring Viscosity and Total Solids Content of Milk Protein Concentrate Using an Inline Acoustic Flowmeter at Laboratory Scale.

Control of milk concentrate viscosity and total solids (TS) content prior to spray drying can improve dairy ingredient manufacture. However, the availability of hygienic and appropriately pressure rated process viscometers for inline monitoring of viscosity is limited. An acoustic flowmeter (FLOWave) is an inline process analytical technology (PAT) tool that measures changes in acoustic signals in response to changes in liquid properties (i.e., acoustic transmission (AT), acoustic impedance (AI), temperature and volume flowrate). In this study, an acoustic flowmeter is evaluated as an inline PAT tool for monitoring viscosity of milk protein concentrate (MPC85), protein and TS content of (MPC85), and standardised MPC (sMPC). Laboratory scale experiments were carried out at 45 °C for five different concentrations (4-21%) of MPC85 and sMPC. Results showed that AT decreased with an increase in MPC85 viscosity (e.g., AT was 98.79 ± 0.04% and 86.65 ± 0.17% for 4% and 21% TS content, respectively). Non-linear regression was carried out to develop a relationship between AT and offline viscosity (R2 (coefficient of determination) value = 0.97 and standard error of prediction = 1.86 mPa·s). AI was observed to increase at higher protein and TS content which was dependent on protein to total solid ratio (P_TSR). Multiple linear regression was carried out to develop the relationship between AI, protein content, TS content and P_TSR. Results demonstrated that AI could be used to monitor the protein and TS content of milk protein concentrate (R2 > 0.96). Overall this study demonstrated the potential of an inline acoustic flowmeter for monitoring process viscosity, protein and TS during dairy concentrate processing.

The Effect of Compositional Changes Due to Seasonal Variation on Milk Density and the Determination of Season-Based Density Conversion Factors for Use in the Dairy Industry.

The objective of this study was to determine the effect of seasonal variation on milk composition and establish an algorithm to predict density based on milk composition to enable the calculation of season-based density conversion calculations. A total of 1035 raw whole milk samples were collected from morning and evening milking of 60 spring-calving individual cows of different genetic groups, namely Jersey, Elite HF (Holstein-Friesian) and National Average HF, once every two weeks for a period of 9 months (March-November, 2018). The average mean and standard deviation for milk compositional traits were 4.72 ± 1.30% fat, 3.85 ± 0.61% protein and 4.69 ± 0.30% lactose and density was estimated at 1.0308 ± 0.002 g/cm3. The density of the milk samples was evaluated using three methods: a portable density meter, DMA 35; a standard desktop version, DMA 4500M; and an Association of Official Agricultural Chemists (AOAC) method using 100-mL glass pycnometers. Statistical analysis using a linear mixed model showed a significant difference in density of milk samples (p < 0.05) across seasonal and compositional variations adjusted for the effects of days in milk, parity, the feeding treatment, the genetic group and the measurement technique. The mean density values and standard error of mean estimated for milk samples in each season, i.e., spring, summer and autumn were 1.0304 ± 0.00008 g/cm3, 1.0314 ± 0.00005 g/cm3 and 1.0309 ± 0.00007 g/cm3, respectively.