Evidence-Based Tools for Dietary Assessments in Nutrition Epidemiology Studies for Dementia Prevention.

Increasing evidence proposes diet as a notable modifiable factor and viable target for the reduction of Alzheimer's Disease risk and age-related cognitive decline. However, assessment of dietary exposures is challenged by dietary capture methods that are prone to misreporting and measurement errors. The utility of -omics technologies for the evaluation of dietary exposures has the potential to improve reliability and offer new insights to pre-disease indicators and preventive targets in cognitive aging and dementia. In this review, we present a focused overview of metabolomics as a validation tool and framework for investigating the immediate or cumulative effects of diet on cognitive health.

DHA-enriched fish oil reduces insulin resistance in overweight and obese adults.

Adipose tissue inflammation is major factor in the development of insulin resistance (IR). Long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are anti-inflammatory bioactive lipids, thus may protect against type 2 diabetes (T2D) development. Previous research has demonstrated a sex-dependent association between LCn-3PUFA and T2D, and evidence suggests LCn-3PUFA may improve IR in a sex-dependent manner. This double-blind, randomized, parallel-arm placebo-controlled study aimed to determine whether DHA-enriched fish oil (FO) supplementation improves IR. Sex-dependent effects were assessed by testing for an interaction between sex and treatment in the multiple regression models. Men and women with abdominal obesity (waist circumference: males, ≥102 cm; females, ≥88 cm) and without diabetes were recruited from the community. Participants (age: 50.9 ± 12.7 years, female: 63.7%, BMI: 32.4 ± 6.6 kg/m2) were randomly allocated to either 2 g FO (860 mg DHA + 120 mg EPA) (intervention, n = 38) or 2 g corn oil (CO) /day (control, n = 35) for 12 weeks in a double-blind randomised controlled trial. A fasting blood sample was collected at 0 and 12 weeks for assessment of IR, glucose and blood lipid profile. Sixty-eight participants completed the intervention. Compared with CO (n = 32), FO (n = 36) significantly reduced fasting insulin by -1.62 µIU/L (95%CI: -2.99, -0.26,) (p = 0.021) and HOMA-IR by -0.40 units (95%CI: -0.78, -0.02, p = 0.038). Higher insulin and HOMA-IR at baseline were associated with greater reductions in the FO group (p < 0.001). There was no interaction between sex and treatment for the change in insulin (p-interactionsex*treatment = 0.816) or HOMA-IR (p-interactionsex*treatment = 0.825). DHA-enriched FO reduces IR in adults with abdominal obesity, however, sex-dependent differences were not evident in this study.

Innovations in veterinary education: the Charles Sturt University programme (Wagga Wagga, Australia).

Veterinary education must adapt to the changing demands that veterinary medicine is obligated to meet as it serves the needs of the ever-increasing global society. The world community needs the help of veterinary professionals to produce sufficient amounts of safe food, to control and eradicate the increasingly frequent transboundary transmission of disease, and to improve the health of both man and animals, at a global level as well as locally. In recognition of these mounting responsibilities, especially in the need for veterinarians in rural practice, one key venture in Australia has been the creation of the new veterinary school in Wagga Wagga. This paper describes the School's mission and, in particular, the nature of the new veterinary programme that has been created.

Effect of different methods of selection on the background, attitudes and career plans of first year veterinary students.

OBJECTIVES: To compare the family, educational and animal-related backgrounds and career aspirations of students who were selected on the basis of academic criteria with those selected using additional criteria. METHODS: Questionnaires were completed during class time in the first few weeks of enrolment by incoming veterinary students at the University of Sydney, who had been selected on the basis of academic background, and at Charles Sturt University, selected using more broadly-based criteria. The data were transferred to an Excel spreadsheet, and frequency distributions and chi2 statistics estimated using the SAS System for Windows 8. RESULTS: Students selected principally on academic criteria alone had higher average UAI scores, were more likely to have completed high school in a capital city, and to have parents with higher education levels than those selected using additional criteria. Both groups indicated that their choice of veterinary science was based largely on their affinity for animals and keenness to work in a veterinary practice. However, those at CSU placed much greater importance than those at Sydney on a desire to live and work in a rural area, and a desire to help farmers. The broad-based selection methods were the main reasons for students applying to CSU whereas the reputation of the university was the main attraction for Sydney students. Two-thirds of CSU students, but one-third of Sydney students, planned to enter rural mixed practice when they graduated, and most planned to stay for at least 10 years. Conversely, no CSU students, but 42% of those at Sydney, planned to enter small animal practice initially. The percentage planning to work full-time in the first, fifth and tenth year after graduation was not significantly different between the two groups. CONCLUSIONS: Criteria which included actual experience with farm animals have resulted in the selection of more students who plan to enter and remain in rural mixed practice. Further studies over the longer term will be necessary to assess the extent to which these plans are realized.

Current approaches to the management of ovine footrot.

Ovine footrot remains the most important cause of lameness in sheep flocks in the UK, despite the existence of proven methods for the control of the disease. Recent research suggests that sheep farmers may be unaware of these methods and may allocate greater resources to treatment of footrot rather than to its prevention. Foot paring, topical treatments, vaccination and parenteral antibiotic therapy all have a role in treating sheep with advanced footrot infections, but prevention of severe infections is best achieved by the timely implementation of control programmes. These are usually based on footbathing and vaccination. For control programmes to be effective it is essential that the pathogenesis and epidemiology of footrot is understood and that control methods are implemented at appropriate times in the season, depending on climatic and pasture conditions. This article reviews these strategies and makes recommendations for steps to reduce the spread of footrot between flocks and to reduce the incidence of footrot within UK flocks.

Intrauterine and transmammary transmission of Mycobacterium avium subsp paratuberculosis in sheep.

OBJECTIVE: To investigate intrauterine infection of foetuses with Mycobacterium avium subsp paratuberculosis and the presence of infection in mammary secretions of sheep. DESIGN: A study of 142 late-pregnant ewes and their foetuses from two heavily infected flocks. PROCEDURE: Infection of ewes was determined at necropsy by histopathology and culture of tissues and mammary secretions. Antemortem tests (clinical assessment, faecal culture and serology) were also applied. Foetuses from 59 infected ewes and 47 apparently uninfected ewes were examined by culture and histopathology. RESULTS: Five of five ewes with clinical ovine Johne's disease had infected foetuses. Only one of 54 subclinically affected ewes, and none of 47 uninfected ewes had an infected foetus. M a paratuberculosis was cultured from mammary secretions or mammary glands of only two of 76 ewes, both of which were clinical cases and had infected foetuses. CONCLUSION: Although intrauterine or transmammary transmission of Mycobacterium avium subsp paratuberculosis may occur frequently in clinically affected sheep, these are less common in subclinically infected ewes. Therefore these modes of transmission are unlikely to compromise existing control programs for ovine Johne's disease on most farms, especially if programs include the immediate culling of clinically affected sheep.

Monte Carlo simulation of flock-level sensitivity of abattoir surveillance for ovine paratuberculosis.

We used Monte Carlo simulation to estimate distributions for flock-level sensitivity of abattoir-based surveillance for ovine paratuberculosis as currently practised in New South Wales, Australia. Probability distributions were used as input variables for within-flock prevalence, years-infected and individual animal-level sensitivity and specificity of gross pathology as a screening test for the presence of paratuberculosis. Distributions used as inputs for the size of abattoir-slaughter groups were based on existing abattoir-surveillance data from NSW. Predicted flock-level sensitivity depended on within-flock prevalence and the number of animals examined and was sensitive to estimates of animal-level sensitivity and specificity. The median probability of detection of an infected flock based on the examination of one abattoir line was predicted not to exceed 0.95 unless the within-flock prevalence was > or =7%. If the within-flock prevalence was 2%, the probability distribution of flock-level sensitivity had a median of 0.73, with 80% of values lying between 0.55 and 0.84. Improvement in the flock-level sensitivity could be achieved by submitting more than three gross pathology-positive specimens per line, if available-but the degree of improvement depended on the number of sheep slaughtered (line size) and the within-flock prevalence. At 2% prevalence, a median flock-level sensitivity of 0.95 could be obtained in lines of >390 sheep if six gross pathology-positive specimens were submitted. We concluded that abattoir surveillance based on identification of gross pathology as a screening test is not a sensitive tool for detecting recently infected flocks or flocks which have a moderate or lower prevalence of infected animals. But-with relatively minor modifications of the protocol currently in use-it could become a key component of a surveillance programme which included additional testing strategies for small flocks.

Effect of climatic region on the clinical expression of footrot of lesser clinical severity (intermediate footrot) in sheep.

OBJECTIVE: To determine if the clinical classification of intermediate footrot (IFR) is changed to virulent footrot (VFR) by a transfer of the infected flock to a region where climatic conditions are more favourable for the transmission of the disease. DESIGN: Clinical examination of two groups of Merino wethers infected with IFR; one group of 309 in a region considered less favourable for footrot and another group of 343 at a second site considered more favourable. PROCEDURES: After characterising the form of footrot at the first site, infection was established at the second site by mixing 142 wethers from the first site with 201 unrelated wethers considered to be free of IFR and VFR. Observations of clinical characteristics were made over a 16 month period during which an outbreak of footrot occurred. Clinical assessments were made by inspecting every foot of every sheep at regular intervals and allocating a footscore. Evidence that the same clonal lines of D. nodosus were responsible for the footrot at both sites was provided by serotyping of isolates and using omp gene RFLP as a molecular epidemiological tool. RESULTS: The disease at the first site was classified as IFR because 7% of the sheep developed a maximum footscore (MFS) of 4, the most severe category, despite relatively low rates of transmission. When the outbreak occurred at the second site, which was more suitable for footrot transmission, the maximum proportion of the flock that developed a MFS of 4 was 3.6%, confirming the initial classification of IFR. CONCLUSIONS: When a flock infected with IFR was moved to a region where climatic conditions were more favourable for footrot transmission, the clinical classification of the disease remained the same in both the original flock and in sheep exposed to the infection for the first time.

Eradication of footrot of lesser clinical severity (intermediate footrot).

OBJECTIVE: To determine if intermediate footrot (IFR) can be eradicated from a flock of sheep by inspection and culling of cases during a non-transmission period and if prior antibiotic treatment or vaccination increases the likelihood of eradication. PROCEDURE: A replicated field experiment that compared the three eradication strategies was followed by an observational study of the best of these applied in a commercial flock of 3000 sheep. RESULTS: In the replicated experiment, IFR was eradicated either by inspection and culling alone, or when combined with vaccination. Eradication failed when the sheep were treated with parenteral antibiotics before inspection and culling during the non-transmission period. In the whole-flock program, eradication by repeated inspection and culling of footrot cases during the non-transmission period was successful and the flock remained free of infection 3 years later. CONCLUSIONS: IFR can be eradicated by inspection and culling but latent infections, which may persist undetected for at least 34 weeks, require surveillance inspections to be repeated during the non-transmission phase of the program. The use of parenteral antibiotics as an aid to the eradication of IFR is contraindicated.

Eradication of virulent footrot from sheep and goats in an endemic area of Nepal and an evaluation of specific vaccination.

Programmes based on the identification and treatment of cases and the culling of animals refractory to treatment had failed to eradicate virulent footrot from two districts in the western region of Nepal. From 1993 to 1996 vaccination against two endemic virulent strains of Dichelobacter nodosus was tested for its potential to contribute to the eradication of footrot from the region. Only sheep and goats which had been free of signs of footrot at three inspections at monthly intervals before their annual migration to alpine pastures were eligible for inclusion. From November 1992, the treatment of cases identified during inspections included the injection of specific vaccine. Successfully treated cases migrated with their flocks but were excluded from the vaccine trial. Non-responding cases were culled. Forty combined flocks of sheep and goats (approximately 9500 animals) were used initially to compare three vaccination regimens. Eleven flocks (sheep and goats) were treated with two doses of specific vaccine (group A), nine (sheep and goats) were treated with commercial vaccine followed by specific vaccine (group B) and 10 (sheep and goats) were treated with two doses of commercial vaccine (group C) in March to April 1993 before the annual migration; 10 flocks (sheep and goats) remained unvaccinated (group D). Only sheep and goats free of signs of footrot were allowed to migrate. Nevertheless, virulent footrot recurred in many flocks three months later. However, its prevalence was significantly lower in group A than in the other three groups combined. Groups A, B and C then received the specific vaccine before their migrations in 1994 to 1996; group D remained unvaccinated. The annual programme of inspection and identification and treatment of cases continued for seven years, but the vaccinations ceased after four years. There was no recurrence of virulent footrot after November 1993. After the first season the virulent strains of D nodosus used in the specific vaccine could no longer be isolated, although antigenically distinct, benign strains of the organism persisted in cases of benign footrot.

Mom empowerment, too! (ME2): a program for young mothers involved in substance abuse.

Substance abuse among young people is of critical concern to public health nurses. When substance abusers are young mothers without the skills, experience, guidance, or resources to become adequate parents, this problem is compounded This study examined a community-based intervention program for young mothers from the perspective of 42 participants. A qualitative, descriptive design was used within a process of participatory action research. Two major domains emerged from the data: risk perceptions and behaviors, and health promoting perceptions and behaviors. The study demonstrated the value of obtaining data from the participants and offers implications for practice and research.

Duration of the persistent activity of moxidectin against Haemonchus contortus in sheep.

Weaned lambs were infected with Haemonchus contortus 35, 28, 21, 14 and 7 days after treatment with moxidectin at 0.2 mg/kg and 35 and 14 days after treatment with ivermectin at the same dose rate. Worm counts 14 days after infection showed that moxidectin prevented the establishment of over 99% of infective larvae for 28 days and reduced the establishment rate at 35 days by 96%, relative to ivermectin. There was no difference in the protective efficacy of ivermectin at 14 or 35 days. The persistence of moxidectin is likely to provide advantages in nematode control, particularly when used as a strategic early summer treatment or as a pre-lambing treatment to ewes. Implications of the persistent activity of moxidectin for the development of resistance during the decay phase are discussed.

Cost-benefit evaluation of artificial insemination for genetic improvement of wool-producing sheep.

The financial costs and benefits associated with the use of artificial insemination (AI) in commercial flocks are evaluated. Benefits are calculated in terms of net present values after summing the discounted value of benefits over 20 years. Two breeding strategies are evaluated. With the first, AI is used to produce flock ewes and wethers. The method is unlikely to be profitable unless high breeding value rams are available for AI programs with fresh semen. With the second, AI is used to produce home-bred rams, which in turn sire flock ewes and wethers. This approach is more likely to be profitable. The cost of AI per lamb weaned from laparoscopic AI programs is about $100. Benefits exceed this cost for rams of very high merit when wool prices are moderate or higher. Flock structure has a significant effect on the benefits. Flocks with low wether retention rates have benefits half that of flocks that retain most wethers to 6 years of age. AI with purchased semen also provides benefits to risk management for owners of commercial flocks who wish to breed their own replacement flock rams.

Misincorporation during DNA synthesis, analyzed by gel electrophoresis.

A method has been developed for simultaneous comparison of the propensity of a DNA polymerase to misincorporate at different points on a natural template-primer. In this method elongation of a [5'-32P] primer, annealed to a bacteriophage template strand, is carried out in the presence of only three dNTPs (highly purified by HPLC). Under these conditions the rate of primer elongation (monitored by gel electrophoresis/autoradiography) is limited by the rate of misincorporation at template positions complementary to the missing dNTP. Variations in the rate of elongation (revealed by autoradiographic banding patterns) reflect variations in the propensity for misincorporation at different positions along the template. The effect on primer elongation produced by addition of a chemically modified dNTP to 'minus' reactions reveals the mispairing potential of the modified nucleotide during DNA synthesis. By use of this electrophoretic assay of misincorporation we have demonstrated that the fidelity of E. coli DNA polymerase I varies greatly at different positions along a natural template, and that BrdUTP and IodUTP can be incorporated in place of dCTP during chain elongation catalyzed by this enzyme.