Chitosan Reduces Enteric Colonization of Campylobacter in Young Chickens, but Not on Post-Harvest Chicken Skin Samples

Worldwide, Campylobacter is one of the leading causes of foodborne bacterial gastroenteritis causing an estimated 1.3 million infections in the United States alone. Consumption and/or cross-contamination of raw or undercooked poultry products have been linked as the most common source of Campylobacter infection, making the poultry industry a target for Campylobacter reduction strategies. Campylobacter is prevalent in most poultry flocks in the United States, with as many as 90% of flocks Campylobacter-positive at the time of slaughter. It is estimated that a reduction of Campylobacter in poultry would greatly reduce the risk of campylobacteriosis in humans. Unfortunately, there are a lack of effective intervention options to reduce Campylobacter in poultry. One potential strategy is the use of the natural product, chitosan, a deacetylated byproduct of crustacean shells, has been shown to reduce E. coli and Salmonella. The purpose of this study was to determine the ability of chitosan to reduce enteric Campylobacter colonization in pre-harvest chickens and on post-harvest chicken skin samples. In each of three trials, 100 birds were divided into 10 treatments (n=10) and were fed either 0% (controls), 0.25%, 0.5% or 1% (wt./wt.) of a low, medium or high molecular weight chitosan (300 birds total). Birds were fed treated feed for the duration of the study and were orally challenged with a four-strain mixture of wild type C. jejuni on day 6. On day 15, the ceca were excised and enumerated for Campylobacter. In all three trials, the 0.5% dose of the medium molecular weight chitosan reduced cecal Campylobacter counts. Because this medium molecular weight chitosan was shown to be the most effective, it was evaluated for post-harvest efficacy against Campylobacter on chicken skin. When a 0.5, 1 or 2% concentration was tested in three separate trials, Campylobacter counts were not reduced when compared to controls. These results support the use of chitosan in pre-harvest chickens but not for the reduction of Campylobacter as a post-harvest rinse on skin for the concentrations and strategy used in this study

Inertia-Free Spacecraft Attitude Tracking with Disturbance Rejection and Almost Global Stabilization

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76737/1/AIAA-41565-705.pd

Effect of yeast culture on milk production and metabolic and reproductive performance of early lactation dairy cows

<p>Abstract</p> <p>Background</p> <p>The main objective of this study was to estimate the effect of supplementation with <it>Saccaromyces cerevisiae (SC</it>) (Yea-Sacc^®1026) on milk production, metabolic parameters and the resumption of ovarian activity in early lactation dairy cows.</p> <p>Methods</p> <p>The experiment was conducted during 2005/2006 in a commercial tied-house farm with an average of 200 milking Estonian Holstein Friesian cows. The late pregnant multiparous cows (n = 46) were randomly divided into two groups; one group received 10 g yeast culture from two weeks before to 14 weeks after calving. The groups were fed a total mixed ration with silages and concentrates. Milk recording data and blood samples for plasma metabolites were taken. Resumption of luteal activity was determined using milk progesterone (P₄) measurements. Uterine bacteriology and ovarian ultrasonography (US) were performed and body condition scores (BCS) and clinical disease occurrences were recorded. For analysis, the statistical software Stata 9.2 and R were used to compute Cox proportional hazard and linear mixed models.</p> <p>Results</p> <p>The average milk production per cow did not differ between the groups (32.7 ± 6.4 vs 30.7 ± 5.3 kg/day in the SC and control groups respectively), but the production of milk fat (<it>P </it>< 0.001) and milk protein (<it>P </it>< 0.001) were higher in the SC group. There was no effect of treatment on BCS. The analysis of energy-related metabolites in early lactation showed no significant differences between the groups. In both groups higher levels of β-hydroxybutyrate (BHB) appeared from days 14 to 28 after parturition and the concentration of non-esterfied fatty acid (NEFA) was higher from days 1–7 post partum (PP). According to US and P₄results, all cows in both groups ovulated during the experimental period. The resumption of ovarian activity (first ovulations) and time required for elimination of bacteria from the uterus did not differ between the groups.</p> <p>Conclusion</p> <p>Supplementation with SC had an effect on milk protein and fat production, but did not influence the milk yield. No effects on PP metabolic status, bacterial elimination from the uterus nor the resumption of ovarian activity were found.</p

Cumulative Inequality in Developmental Education: How Does State Policy Address It?

This study frames the need to understand if and how language related to equity and inequality manifests in state-level developmental education policy. State-level legislation has been a popular mechanism for reforming developmental education (DE) but despite reforms, low success rates and inequitable outcomes have persisted. Little is known about whether the language in DE policy has an equity focus or addresses the cumulative inequality students will have experienced at the point of entering higher education. Cumulative Inequality Theory (CIT) was utilized as a theoretical foundation to inform this study--a content analysis examining state-level DE policy created between 2012 and 2021 to quantify how many states that introduced new DE policy included an equity focus and the qualities of the language included. CIT has been used in health science to show that “social systems generate inequality, which is manifested over the life course via demographic and developmental processes, and that personal trajectories are shaped by the accumulation of risk, available resources, perceived trajectories, and human agency” (Ferraro & Shippee, 2009, p. 334). Of the seventeen states that revised DE policy in the last nine years, only eight states included an equity focus in the language of their DE bills. States varied in their use of general or specific acknowledgments of disproportionate impact, mentions of impacted groups, or requirements that DE data be disaggregated. Additionally, findings showed that legislation addressed cumulative inequality in the following ways: (1) providing resources at different points in a student’s educational trajectory to change future outcomes, (2) mitigating risk by providing information about DE or shortening the DE sequences, and (3) requiring longitudinal or cohort-specific data on student success rates. The descriptive findings of this content analysis on DE policy have important implications. The state-by-state comparison of equity-focused language can help legislatures and policymakers see how their legislative bills compare to other states and whether their intended goals are clear in the policy language. Few bills specifically name disproportionately impacted groups, but if the goal is to reduce equity gaps for those groups, those creating legislation may want to consider how to best address the needs of those groups and track their progress. The findings of this study point to a need for additional research that investigates what the most effective ways are to mitigate cumulative inequality in developmental education

A summary of recent Kansas State University research on the metabolism of supplemental niacin in the rumen of cattle

Benefits have been shown under certain conditions when niacin is added to the diets of beef cattle, dairy cattle or sheep. We attempted to find out what effects added niacin has on the rumen fermentation, and conversely, how the rumen metabolizes niacin