Nutritional supplements, leptin, insulin and progesterone in female Australian Cashmere goats

In small ruminants, reproductive wastage due to early embryo mortality is a major industry issue because it reduces reproductive efficiency and limits productivity. In sheep, early embryo mortality appears to be caused by reductions in progesterone concentrations when animals are over-fed, but this concept has not been studied in goats. Therefore we tested whether a supplement of lupin grain affects circulating progesterone concentrations in Cashmere goats during non- breeding season. We allocated 23 females into two groups: Controls were fed to ensure maintenance of body mass (85% chaff, 15% lupins head daily); Supplemented goats were fed twice their daily requirements for maintenance. All animals were anovulatory and treated with CIDRs to supply exogenous progesterone at a relatively constant rate. Nutritional treatments lasted for 18 days, and coincided with the presence of CIDRs. Leptin and insulin concentrations were increased (p < 0.05) by supplementation, but progesterone concentrations did not significant differ between groups at any time during the experiment. We conclude that a dietary supplement that elicits major changes in energy homeostasis does not reduce progesterone concentrations in goats and is thus unlikely to affect embryo mortality

Phyto-oestrogens affect fertilisation and embryo development in vitro in sheep

Phyto-oestrogens such as isoflavones are natural compounds that can profoundly affect reproductive function. In the present study, we tested whether including isoflavone compounds (genistein, biochanin A, formononetin) in the maturation medium would affect the outcomes for ovine oocytes in vitro. Each isoflavone compound was evaluated at five concentrations (0, 2.5, 5, 10, 25µgmL-1) and the entire protocol was repeated four times. Cumulus-oocyte complexes were randomly allocated to the treatments, then fertilised and cultured in vitro. Compared with control (0µgmL-1), the lower concentrations of isoflavone (2.5, 5 and 10µgmL-1) had no detectable effect on the rates of cleavage or embryo development, or on embryo total cell counts (TCC). However, the highest concentration (25µgmL-1) of all three isoflavones exerted a variety of effects (P<0.05): genistein decreased cleavage rate, blastocyst rate and blastocyst efficiency (blastocysts produced per 100 oocytes); biochanin A decreased cleavage rate and blastocyst efficiency; and formononetin decreased blastocyst rate and blastocyst efficiency. Biochanin A (25µgmL-1) reduced embryo TCC specifically at the hatched blastocyst stage (P<0.05). We conclude that the presence of isoflavones at 25µgmL-1 during IVM decreases the cleavage rate and inhibits blastocyst hatching

Do incentives, reminders or reduced burden improve healthcare professional response rates in postal questionnaires?:Two randomized controlled trials

BACKGROUND: Healthcare professional response rates to postal questionnaires are declining and this may threaten the validity and generalisability of their findings. Methods to improve response rates do incur costs (resources) and increase the cost of research projects. The aim of these randomised controlled trials (RCTs) was to assess whether 1) incentives, 2) type of reminder and/or 3) reduced response burden improve response rates; and to assess the cost implications of such additional effective interventions. METHODS: Two RCTs were conducted. In RCT A general dental practitioners (dentists) in Scotland were randomised to receive either an incentive; an abridged questionnaire or a full length questionnaire. In RCT B non-responders to a postal questionnaire sent to general medical practitioners (GPs) in the UK were firstly randomised to receive a second full length questionnaire as a reminder or a postcard reminder. Continued non-responders from RCT B were then randomised within their first randomisation to receive a third full length or an abridged questionnaire reminder. The cost-effectiveness of interventions that effectively increased response rates was assessed as a secondary outcome. RESULTS: There was no evidence that an incentive (52% versus 43%, Risk Difference (RD) -8.8 (95%CI −22.5, 4.8); or abridged questionnaire (46% versus 43%, RD −2.9 (95%CI −16.5, 10.7); statistically significantly improved dentist response rates compared to a full length questionnaire in RCT A. In RCT B there was no evidence that a full questionnaire reminder statistically significantly improved response rates compared to a postcard reminder (10.4% versus 7.3%, RD 3 (95%CI −0.1, 6.8). At a second reminder stage, GPs sent the abridged questionnaire responded more often (14.8% versus 7.2%, RD −7.7 (95%CI −12.8, -2.6). GPs who received a postcard reminder followed by an abridged questionnaire were most likely to respond (19.8% versus 6.3%, RD 8.1%, and 9.1% for full/postcard/full, three full or full/full/abridged questionnaire respectively). An abridged questionnaire containing fewer questions following a postcard reminder was the only cost-effective strategy for increasing the response rate (£15.99 per response). CONCLUSIONS: When expecting or facing a low response rate to postal questionnaires, researchers should carefully identify the most efficient way to boost their response rate. In these studies, an abridged questionnaire containing fewer questions following a postcard reminder was the only cost-effective strategy. An increase in response rates may be explained by a combination of the number and type of contacts. Increasing the sampling frame may be more cost-effective than interventions to prompt non-responders. However, this may not strengthen the validity and generalisability of the survey findings and affect the representativeness of the sample

The ovarian follicle of ruminants: The path from conceptus to adult

This review resulted from an international workshop and presents a consensus view of critical advances over the past decade in our understanding of follicle function in ruminants. The major concepts covered include: (1) the value of major genes; (2) the dynamics of fetal ovarian development and its sensitivity to nutritional and environmental influences; (3) the concept of an ovarian follicle reserve, aligned with the rise of anti-Müllerian hormone as a controller of ovarian processes; (4) renewed recognition of the diverse and important roles of theca cells; (5) the importance of follicular fluid as a microenvironment that determines oocyte quality; (6) the \u27adipokinome\u27 as a key concept linking metabolic inputs with follicle development; and (7) the contribution of follicle development to the success of conception. These concepts are important because, in sheep and cattle, ovulation rate is tightly regulated and, as the primary determinant of litter size, it is a major component of reproductive efficiency and therefore productivity. Nowadays, reproductive efficiency is also a target for improving the \u27methane efficiency\u27 of livestock enterprises, increasing the need to understand the processes of ovarian development and folliculogenesis, while avoiding detrimental trade-offs as greater performance is sought

Systematic review and network meta-analysis with individual participant data on cord management at preterm birth (iCOMP): study protocol

Introduction Timing of cord clamping and other cord management strategies may improve outcomes at preterm birth. However, it is unclear whether benefits apply to all preterm subgroups. Previous and current trials compare various policies, including time-based or physiology-based deferred cord clamping, and cord milking. Individual participant data (IPD) enable exploration of different strategies within subgroups. Network meta-analysis (NMA) enables comparison and ranking of all available interventions using a combination of direct and indirect comparisons. Objectives (1) To evaluate the effectiveness of cord management strategies for preterm infants on neonatal mortality and morbidity overall and for different participant characteristics using IPD meta-analysis. (2) To evaluate and rank the effect of different cord management strategies for preterm births on mortality and other key outcomes using NMA. Methods and analysis Systematic searches of Medline, Embase, clinical trial registries, and other sources for all ongoing and completed randomised controlled trials comparing cord management strategies at preterm birth (before 37 weeks’ gestation) have been completed up to 13 February 2019, but will be updated regularly to include additional trials. IPD will be sought for all trials; aggregate summary data will be included where IPD are unavailable. First, deferred clamping and cord milking will be compared with immediate clamping in pairwise IPD meta-analyses. The primary outcome will be death prior to hospital discharge. Effect differences will be explored for prespecified participant subgroups. Second, all identified cord management strategies will be compared and ranked in an IPD NMA for the primary outcome and the key secondary outcomes. Treatment effect differences by participant characteristics will be identified. Inconsistency and heterogeneity will be explored. Ethics and dissemination Ethics approval for this project has been granted by the University of Sydney Human Research Ethics Committee (2018/886). Results will be relevant to clinicians, guideline developers and policy-makers, and will be disseminated via publications, presentations and media releases

Whole body cardiovascular magnetic resonance imaging to stratify symptomatic and asymptomatic atherosclerotic burden in patients with isolated cardiovascular disease

BACKGROUND: The aim of this study was to use whole body cardiovascular magnetic resonance imaging (WB CVMR) to assess the heart and arterial network in a single examination, so as to describe the burden of atherosclerosis and subclinical disease in participants with symptomatic single site vascular disease. METHODS: 64 patients with a history of symptomatic single site vascular disease (38 coronary artery disease (CAD), 9 cerebrovascular disease, 17 peripheral arterial disease (PAD)) underwent whole body angiogram and cardiac MR in a 3 T scanner. The arterial tree was subdivided into 31 segments and each scored according to the degree of stenosis. From this a standardised atheroma score (SAS) was calculated. Cine and late gadolinium enhancement images of the left ventricle were obtained. RESULTS: Asymptomatic atherosclerotic disease with greater than 50 % stenosis in arteries other than that responsible for their presenting complain was detected in 37 % of CAD, 33 % of cerebrovascular and 47 % of PAD patients. Unrecognised myocardial infarcts were observed in 29 % of PAD patients. SAS was significantly higher in PAD patients 24 (17.5-30.5) compared to CAD 4 (2–11.25) or cerebrovascular disease patients 6 (2-10) (ANCOVA p < 0.001). Standardised atheroma score positively correlated with age (β 0.36 p = 0.002), smoking status (β 0.34 p = 0.002), and LV mass (β -0.61 p = 0.001) on multiple linear regression. CONCLUSION: WB CVMR is an effective method for the stratification of cardiovascular disease. The high prevalence of asymptomatic arterial disease, and silent myocardial infarctions, particularly in the peripheral arterial disease group, demonstrates the importance of a systematic approach to the assessment of cardiovascular disease