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The objective of this study was to create various pH/temp decline rates in hot-boned bull beef M. longissimus lumborum (LL) through a combination of electrical stimulation (ES) and pre-rigor holding temperature. The relationship between the pre-rigor interventions, the activities of µ-calpain and small heat shock proteins (sHSP), and the impacts on meat product quality were determined. Paired LL loins from 13 bulls were hot-boned within 40 min of slaughter, immediately ES and subjected to various holding temperatures (5, 15, 25, and 35°C) for 3 hr. The rate of muscle pH decline, sarcomere length, shear force, and proteolysis of muscle proteins were measured. ES-25°C had a longer sarcomere length compared to non-electrical stimulation samples. ES-25°C and ES-35°C samples had lower shear force values, higher µ-calpain activity and higher desmin, troponin-T, and sHSP degradation. The above findings suggest that pH/temp decline rates created in hot-boned muscle impacted muscle protein proteolysis by increasing the activity of proteases and degradation of sHSP.

Introduction and Aims: Needle‐syringe programs (NSP) are an underutilized source of data on drug injection trends; these data are essential for informing public health interventions. We examine trends in NSP service occasions from 2007–2015. Design and Methods: Using standardised data from 26 NSP outlets through the Queensland NSP Minimum Data Set (QNSPMDS), trends in service occasions among clients intending to inject methamphetamine, heroin, opioid substitution therapy (OST) medications and other pharmaceutical opioids were assessed using multilevel mixed‐effects negative binomial regression, adjusting for month, year, age and clustering by site. Results: Over 1.5 million service occasions were recorded in 2007-2015. Methamphetamine was the main ‘drug intended to inject’ (33.7%), however cf. 2007, the incidence rate ratio decreased to 0.64 (95% CI: 0.62, 0.66) in 2009, remaining low until 2015. Among clients reporting methamphetamine injection, there was a shift in the form from base to the higher‐potency crystal methamphetamine since 2012. Heroin injection (22.5% service occasions) initially increased (cf. 2007), followed by a decline to 0.77 (95% CI: 0.75, 0.79) in 2015. Significant and sustained increases in OST and other pharmaceutical opioids injection were observed throughout the study period, accounting for 7.2% and 19.8% of total visits, respectively. Discussion and Conclusions: The QNSPMDS provides unique, routinely collected, jurisdiction‐wide and standardised data on the demographics of people who inject drugs, types of drugs injected and regional variations; these data are essential in informing policy, planning and program implementation. There remains significant opportunity to enhance engagement and linkage to care alongside needle‐syringe provision.

INTRODUCTION AND AIMS: An understanding of the relationship between hepatitis C viral (HCV) infection and contextual factors such as imprisonment may contribute to the development of targeted treatment and prevention programs. We examine the associations of imprisonment and drug dependence with lifetime exposure to HCV, and whether these associations differ for Aboriginal and Torres Strait Islander and non-Indigenous people who inject drugs. DESIGN AND METHODS: Respondent-driven sampling was used in major cities and 'peer recruitment' in regional towns of Queensland to obtain a community sample of people who injected drugs, which comprised 243 Indigenous and 227 non-Indigenous participants who had ever been tested for HCV. Data are cross-sectional. Two binary Poisson models were developed to examine associations for variables relating to imprisonment, Indigeneity and drug use history. RESULTS: Sharing needles and syringes in prison (adjusted risk ratio 1.25, 95% confidence interval 1.02-1.53) remained significantly associated with HCV infection after adjustment for Indigeneity, injecting drug use history and drug dependence. Opioid dependence and concurrent dependence on opioids and methamphetamine was also independently associated with HCV infection. DISCUSSION AND CONCLUSIONS: Sharing needles and syringes in prison is linked with HCV infection, for both Aboriginal and Torres Strait Islander and non-Indigenous people who inject drugs. Further development of treatment and prevention programs in prisons is required, with consideration of the role of opioid and methamphetamine dependence in HCV exposure.

Introduction and Aims: Despite over-representation of Indigenous Australians in sentinel studies of injecting drug use, little is known about relevant patterns of drug use and dependence. This study compares drug dependence and possible contributing factors in Indigenous and non-Indigenous Australians who inject drugs. Design and Methods: Respondent-driven sampling was used in major cities and ‘peer recruitment’ in regional towns of Queensland to obtain a community sample of Indigenous (n = 282) and non-Indigenous (n = 267) injectors. Data are cross sectional. Multinomial models were developed for each group to examine types of dependence on injected drugs (no dependence, methamphetamine-dependent only, opioid-dependent only, dependent on methamphetamine and opioids). Results: Around one-fifth of Indigenous and non-Indigenous injectors were dependent on both methamphetamine and opioids in the previous 12 months. Psychological distress was associated with dual dependence on these drugs for Indigenous [adjusted relative risk (ARR) 4.86, 95% confidence interval (CI) 2.08–11.34] and non-Indigenous (ARR 4.14, 95% CI 1.59–10.78) participants. Unemployment (ARR 8.98, 95% CI 2.25–35.82) and repeated (> once) incarceration as an adult (ARR 3.78, 95% CI 1.43–9.97) were associated with dual dependence for Indigenous participants only. Indigenous participants had high rates of alcohol dependence, except for those dependent on opioids only. Discussion and Conclusions: The drug dependence patterns of Indigenous and non-Indigenous people who inject drugs were similar, including the proportions dependent on both methamphetamine and opioids. However, for Indigenous injectors, there was a stronger association between drug dependence and contextual factors such as unemployment and incarceration. Expansion of treatment options and community-level programs may be required. [Smirnov A, Kemp R, Ward J, Henderson S, Williams S, Dev A, Najman J M. Patterns of drug dependence in a Queensland (Australia) sample of Indigenous and non-Indigenous people who inject drugs. Drug Alcohol Rev 2016;35:611-619].

Aims To examine prospectively the contribution of the recreational social environment to ecstasy initiation. Design Population-based retrospective/prospective cohort study. Setting Data from screening an Australian young adult population to obtain samples of users and non-users of ecstasy. Participants A sample of 204 ecstasy-naive participants aged 19–23 years was obtained, and a 6-month follow-up identified those who initiated ecstasy use. Measurements We assessed a range of predictors of ecstasy initiation, including elements of participants' social environment, such as ecstasy-using social contacts and involvement in recreational settings. Findings More than 40% of ecstasy-naive young adults reported ever receiving ecstasy offers. Ecstasy initiation after 6 months was predicted independently by having, at recruitment, many ecstasy-using social contacts [adjusted relative risk (ARR) 3.15, 95% confidence interval (CI): 1.57, 6.34], attending electronic/dance music events (ARR 6.97, 95% CI: 1.99, 24.37), receiving an ecstasy offer (ARR 4.02, 95% CI: 1.23, 13.10), early cannabis use (ARR 4.04, 95% CI: 1.78, 9.17) and psychological distress (ARR 5.34, 95% CI: 2.31, 12.33). Adjusted population-attributable fractions were highest for ecstasy-using social contacts (17.7%) and event attendance (15.1%). Conclusions In Australia, ecstasy initiation in early adulthood is associated predominantly with social environmental factors, including ecstasy-using social contacts and attendance at dance music events, and is associated less commonly with psychological distress and early cannabis use, respectively. A combination of universal and targeted education programmes may be appropriate for reducing rates of ecstasy initiation and associated harms.

Summary The aim of this study was to develop a multiple trait genetic evaluation and selection tool for maternal productivity in beef cattle, particularly in the Hereford breed. Component traits of the maternal productivity index (MPI) were chosen on the basis of their potential to contribute to consistently weaning heavy calves over a sustained herd life, while controlling cow maintenance costs. (Co)variance components were estimated with a multiple trait model including direct and maternal birth weight, direct and maternal weaning weight, weight of the cow at the time her calf is weaned and survival, defined as the ability of a female to produce at least three calves given she became a dam. Although direct and maternal birth weight were included in the (co)variance parameters model, these traits were not included in the index. Estimates of heritability were 0.19, 0.18, 0.50 and 0.07 for direct and maternal weaning weight, cow weight, and survival, respectively. The correlation between direct and maternal components of weaning weight was −0.42. The genetic correlation estimated between direct weaning weight and cow weight was 0.85, while a low genetic correlation of −0.17 was estimated between maternal weaning weight and cow weight. Survival had a near zero (−0.01) genetic correlation with maternal weaning weight, but negative genetic correlations with direct weaning weight (−0.52) and cow weight (−0.48). The MPI was constructed as a linear function of derived economic weights multiplied by estimated breeding values for the four component traits from the model. Estimated economic values were $3.00, $2.70, $−0.49 and $2.39 for direct and maternal weaning weight, cow weight, and survival (expressed as a percentage), respectively. Relative economic weights were 0.30, 0.26, 0.17 and 0.27 for direct and maternal weaning weight, cow weight, and survival, respectively. A simulation study indicated that positive genetic trend would be expected in all component traits although increases in cow weight would be moderate. Zusammenfassung Selektion auf multiple maternale Produktivitatsmerkmale in Fleischrindern Das Ziel der Arbeit war die Entwicklung eines Evaluierungs- und Selektionssystems fur ein zusammengesetztes Merkmal maternaler Produktivitat in Fleischrindern, speziell in Hereford. Die verwendeten Einzelmerkmale des maternalen Produktivitatsindexes basieren auf ihrem potentiellen Nutzen fur die Produktion schwerer Absetzer bei langer Nutzungsdauer und gleichzeitiger Minimierung der Erhaltungskosten. Es wurden (Ko-)varianzkomponenten innerhalb eines zusammengesetzten Modells geschatzt, das direktes und maternales Geburtsgewicht, direktes und maternales Absetzgewicht, Gewicht der Kuh zum Absetzzeitpunkt und die Nutzungsdauer, welche als die Fahigkeit einer Kuh mindestens drei Kalber zu erzeugen definiert wurde, einbezieht. Obwohl direktes und maternales Geburtsgewicht als (Ko-)varianz Parameter berucksichtigt wurden, wurden diese Merkmale nicht mit in den Index einbezogen. Es wurden Schatzwerte fur die Heritabilitaten von jeweils 0,19, 0,18, 0,50 und 0,07 fur das direkte und maternale Absetzgewicht, Gewicht der Kuh und Nutzungsdauer, geschatzt. Die Korrelation zwischen direkten und maternalen Komponenten des Absetzgewichtes betrugen –0,42. Die genetische Korrelation zwischen dem direkten Absetzgewicht und dem Gewicht der Kuh betrug 0,85, wahrend eine geringe Korrelation von –0,17 zwischen maternalem Absetzgewicht und Kuhgewicht geschatzt wurde. Die Nutzungsdauer zeigte keine Korrelation mit dem maternalen Absetzgewicht (−0,01), aber es wurden negative Korrelationen mit dem direkten Absetzgewicht (−0,52) und dem Gewicht der Kuh (−0,48) festgestellt. Der maternale Produktivitatsindex wurde als lineare Funktion der abgeleiteten okonomischen Gewichte, multipliziert mit den geschatzten Zuchtwerten der vier Einzelmerkmale, konstruiert. Die geschatzten okonomischen Werte waren 3,00$, 2,70$, 0,49$ und 2,39$, jeweils fur direktes und maternales Absetztgewicht, Gewicht der Kuh und Nutzungsdauer (ausgedruckt als Prozentsatz). Die relativen okonomischen Gewichtungen betrugen jeweils 0,30, 0,26, 0,17 und 0,27 fur direktes und maternales Absetzgewicht, Gewicht der Kuh und Nutzungsdauer. Eine Simulationsstudie zeigt, dass ein positiver genetischer Trend in allen berucksichtigten Merkmalen zu erwarten ist, wobei die Zunahme des Gewichtes der Kuhe masig bleibt.