Pre-Weaned Calf Rearing on Northern Irish Dairy Farms—Part 2: The Impact of Hygiene Practice on Bacterial Levels in Dairy Calf Rearing Environments

Publication history: Accepted - 18 March 2023; Published - 21 March 2023.Pre-weaned dairy calves are very susceptible to disease in the first months of life due to having a naïve immune system and because of the numerous physiological stressors they face. Hygiene management is a key element in minimizing enteric disease risk in calves by reducing their exposure to pathogens. Samples of milk, concentrate feed and drinking water, boot swabs of bedding and swabs of feed equipment were collected from 66 dairy farms as part of a survey of calf rearing practice and housing design. All the samples were cultured to determine total viable counts (TVC), total coliforms (TCC) and Escherichia coli as indicators of hygiene. Target ranges for levels of TVC, TCC and E. coli were defined from the literature and the sample results compared against them. The TVC targets in milk, MR and water were <4.0 log10 CFU/mL. TCC and E. coli targets of <1.1 log10 CFU/mL (the detection limit) were used for milk, MR, concentrate feed and feeding equipment. For water, the TCC and E. coli targets were <1.0 log10 CFU/100 mL. The targets used for bedding boot swabs were <6.3 log10 TVC CFU/mL and <5.7 log10 TCC or E. coli CFU/mL. Farm management factors were included as fixed effects in a generalized linear mixed model to determine the probability of samples being within each hygiene indicator target range. Milk replacer samples obtained from automatic feeders were more likely to be within the TVC target range (0.63 probability) than those prepared manually (0.34) or milk samples taken from the bulk tank (0.23). Concentrate feed samples taken from buckets in single-calf pens were more likely to have E. coli detected (0.89) than samples taken from group pen troughs (0.97). A very small proportion of water samples were within the indicator targets (TVC 9.8%, TCC 6.0%, E. coli 10.2%). Water from self-fill drinkers had a lower likelihood of being within the TVC target (0.03) than manually filled buckets (0.14), and water samples from single pens were more likely to be within TCC target ranges (0.12) than those from group pens (0.03). However, all self-fill drinkers were located in group pens so these results are likely confounded. Where milk feeders were cleaned after every feed, there was a greater likelihood of being within the TVC target range (0.47, compared with 0.23 when not cleaned after every feed). Detection of coliforms in milk replacer mixing utensils was linked with reduced probability of TVC (0.17, compared with 0.43 when coliforms were not detected) and TCC (0.38, compared with 0.62), which was within target in feeders. Key factors related to increased probability of bedding samples being within TCC target range were use of group calf pens (0.96) rather than single-calf pens (0.80), use of solid floors (0.96, compared with 0.76 for permeable floors) and increased space allowance of calves (0.94 for pens with ≥2 m2/calf, compared with 0.79 for pens with <2 m2/calf). Bedding TVC was more likely to be within the target range in group (0.84) rather than in single pens (0.66). The results show that hygiene levels in the calf rearing environment vary across farms and that management and housing design impact hygiene.This research was funded by the Department of Agriculture, Environment and Rural Affairs (DAERA) project 17 1 03 with co-funding by Agrisearch

Feed Restriction Modulates the Fecal Microbiota Composition, Nutrient Retention, and Feed Efficiency in Chickens Divergent in Residual Feed Intake

Publication histroy: Accepted - 23 October 2018; Published - 19 November 2019.There is a great interest to understand the impact of the gut microbiota on host’s nutrient use and FE in chicken production. Both chicken’s feed intake and gut bacterial microbiota differ between high and low-feed efficient chickens. To evaluate the impact of the feed intake level on the feed efficiency (FE)-associated variation in the chicken intestinal microbiota, differently feed efficient chickens need to eat the same amount of feed, which can be achieved by feeding chickens restrictively. Therefore, we investigated the effect of restrictive vs. ad libitum feeding on the fecal microbiome at 16 and 29 days posthatch (dph), FE and nutrient retention in chickens of low and high residual feed intake (RFI; metric for FE). Restrictively fed chickens were provided the same amount of feed which corresponded to 85% of the ad libitum fed group from 9 dph. FE was determined for the period between 9 and 30 dph and feces for nutrient retention were collected on 31 to 32 dph. From the 112 chickens (n = 56 fed ad libitum, and n = 56 fed restrictively), 14 low RFI and 15 high RFI ad libitum fed chickens, and 14 low RFI (n = 7 per sex) and 14 high RFI restrictively fed chickens were selected as the extremes in RFI and were retrospectively chosen for data analysis. Bray-Curtis dissimilarity matrices showed significant separation between time points, and feeding level groups at 29 dph for the fecal bacterial communities. Relevance networking indicated positive associations between Acinetobacter and feed intake at 16 dph, whereas at 29 dph Escherichia/Shigella and Turicibacter positively and Lactobacillus negatively correlated to chicken’s feed intake. Enterobacteriaceae was indicative for low RFI at 16 dph, whereas Acinetobacter was linked to high RFI across time points. However, restrictive feeding-associated changes in the fecal microbiota were not similar in low and high RFI chickens, whichmay have been related to the higher nutrient retention and thus lower fecal nutrient availability in restrictively fed high RFI chickens. Thismay also explain the decreased RFI value in restrictively fed high RFI chickens indicating improved FE, with a stronger effect in females.This project (ECO-FCE) has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement No. 311794

Capturing the whole-school food environment in primary schools

Abstract Objective: The school food environment is an ideal setting for encouraging healthy dietary behaviour. We aimed to develop an instrument to assess whole-school food environments; test the instrument in the school setting; and demonstrate its use to make food environment recommendations. Design: School food environment literature and UK school food guidance was searched to inform instrument items. The instrument consisted of (i) an observation proforma capturing canteen areas systems, food presentation and monitoring of food intake, and (ii) a questionnaire assessing food policies, provision and activities. The instrument was tested in schools and used to develop school food environment recommendations. Descriptive analyses enabled narrative discussion. Setting: Primary schools. Participants: An observation was undertaken at schools in urban and rural geographical regions of Northern Ireland of varying socio-economic status (n=18). School senior management completed the questionnaire with input from school caterers (n=16). Results: The instrument captured desired detail and potential instrument modifications were identified. School food environments varied. Differences existed between food policies and how policies were implemented and monitored. At many schools there was scope to enhance physical eating environments (n=12, 67%) and food presentation (n=15, 83%); emphasise healthy eating through food activities (n=7, 78%); and increase parental engagement in school food (n=9, 56%). Conclusions: The developed instrument can measure whole-school food environments in primary schools and also enabled identification of recommendations to enhance school food environments. Further assessment and adaptation of the instrument is required to enable future use as a research tool or for self-assessment use by schools

Metformin is a metabolic modulator and radiosensitiser in rectal cancer

Resistance to neoadjuvant chemoradiation therapy, is a major challenge in the management of rectal cancer. Increasing evidence supports a role for altered energy metabolism in the resistance of tumours to anti-cancer therapy, suggesting that targeting tumour metabolism may have potential as a novel therapeutic strategy to boost treatment response. In this study, the impact of metformin on the radiosensitivity of colorectal cancer cells, and the potential mechanisms of action of metformin-mediated radiosensitisation were investigated. Metformin treatment was demonstrated to significantly radiosensitise both radiosensitive and radioresistant colorectal cancer cells in vitro. Transcriptomic and functional analysis demonstrated metformin-mediated alterations to energy metabolism, mitochondrial function, cell cycle distribution and progression, cell death and antioxidant levels in colorectal cancer cells. Using ex vivo models, metformin treatment significantly inhibited oxidative phosphorylation and glycolysis in treatment naïve rectal cancer biopsies, without affecting the real-time metabolic profile of non-cancer rectal tissue. Importantly, metformin treatment differentially altered the protein secretome of rectal cancer tissue when compared to non-cancer rectal tissue. Together these data highlight the potential utility of metformin as an anti-metabolic radiosensitiser in rectal cancer

Dissecting the Shared Genetic Architecture of Suicide Attempt, Psychiatric Disorders, and Known Risk Factors

Background Suicide is a leading cause of death worldwide, and nonfatal suicide attempts, which occur far more frequently, are a major source of disability and social and economic burden. Both have substantial genetic etiology, which is partially shared and partially distinct from that of related psychiatric disorders. Methods We conducted a genome-wide association study (GWAS) of 29,782 suicide attempt (SA) cases and 519,961 controls in the International Suicide Genetics Consortium (ISGC). The GWAS of SA was conditioned on psychiatric disorders using GWAS summary statistics via multitrait-based conditional and joint analysis, to remove genetic effects on SA mediated by psychiatric disorders. We investigated the shared and divergent genetic architectures of SA, psychiatric disorders, and other known risk factors. Results Two loci reached genome-wide significance for SA: the major histocompatibility complex and an intergenic locus on chromosome 7, the latter of which remained associated with SA after conditioning on psychiatric disorders and replicated in an independent cohort from the Million Veteran Program. This locus has been implicated in risk-taking behavior, smoking, and insomnia. SA showed strong genetic correlation with psychiatric disorders, particularly major depression, and also with smoking, pain, risk-taking behavior, sleep disturbances, lower educational attainment, reproductive traits, lower socioeconomic status, and poorer general health. After conditioning on psychiatric disorders, the genetic correlations between SA and psychiatric disorders decreased, whereas those with nonpsychiatric traits remained largely unchanged. Conclusions Our results identify a risk locus that contributes more strongly to SA than other phenotypes and suggest a shared underlying biology between SA and known risk factors that is not mediated by psychiatric disorders.Peer reviewe

Large variation in the movement of individual broiler chickens tracked in a commercial house using ultra-wideband backpacks

Abstract Our understanding of the movement patterns of individual broiler chickens in large flocks is extremely limited. Here we report the use of a Real Time Locating System to track individual broilers in a house of 28 000 birds. Broilers were fitted with backpacks containing ultra-wideband tags on day 21 (N = 8 broilers) or day 24 (N = 9 broilers), with tags recording positioning and distance data until Day 38. Tagged birds were penned overnight on Day 31 to avoid ‘thinning’. We found no clear evidence of broilers consistently creating similar sized “home ranges”. Some broilers spent most time < 10 m from where they were originally found while others visited at least 90% of the house in the period before thinning. While some broilers rapidly returned to the area they were collected from at thinning, the majority did not. Movement data suggested that broilers that restricted themselves to smaller areas of the house were not necessarily less active. Although there was an average reduction in movement with age, this was not linear and there was individual variation. There was also no clear association between movement patterns and broiler weight or gait score, suggesting a more complicated relationship between activity, ranging and some welfare measures

Health, welfare and lifetime performance implications of alternative hatching and early life management systems for broiler chickens

Broiler chicks are typically hatched in a hatchery, exposing them to handling and transportation before being placed on the farm where (dry) feed and water is offered. This study compared different early life systems, including: (1) typical practice (control), (2) typical practice with wet feed offered upon placement, (3) access to water at the hatchery, (4) access to feed and water at the hatchery, (5) hatching on the farm. Birds were placed in groups of approximately 500 (day 0), with six replicates per treatment. Measures were taken between placement and slaughter (day 39) and included chick quality (navel and red hock scores), body weight, feed conversion ratio (FCR), mortality, gait and litter conditions scores, and behavioral and post-mortem assessments. There were no apparent treatment effects on gait score, play behaviour or novel object test measures, and no consistent effects on litter quality. Chick quality was only evaluated in Treatments 1 and 5 and was numerically worse in Treatment 5. Body weight at slaughter was lowest in Treatment 2, and did not differ between other treatments. Overall FCR was lowest (best) in Treatment 1, and did not differ between other treatments. There was higher overall mortality in Treatments 3 and 4 than in other treatments apart from Treatment 5. Treatment 4 appeared to promote feeding behaviour upon placement, and Treatment 5 birds rested the most, significantly more than in Treatment 2. Treatment 5 birds had the greatest bursa weights, and tibial dyschondroplasia appeared worse in Treatment 4. There were no consistent effects of early access to feed and water on gastrointestinal tract weight measures at slaughter. Compared to the control, there were few benefits in providing feed and/or water in the hatchery, or wet feed. Some benefits of in-house hatching were found, but negative effects were also apparent

A schematic representation of the ADAR and related ADAD proteins present in humans.

<p>All proteins have dsRNA binding domains (grey box) and a C-terminal deaminase domain (purple box). A nuclear localization sequence (NLS) is marked in red, whereas the nuclear export signal (NES) present in ADAR1 is marked in green. Z-DNA binding domains are indicated by an orange box in ADAR1. A region enriched in arginine/lysine residues, R domain is present in ADAR3 (blue box). The number of amino acids is indicated on the right.</p