Intramuscular fat in lamb muscle and the impact of selection for improved carcass lean meat yield

Intramuscular fat percentage (IMF%) has been shown to have a positive influence on the eating quality of red meat. Selection of Australian lambs for increased lean tissue and reduced carcass fatness using Australian Sheep Breeding Values has been shown to decrease IMF% of the Muscularis longissimus lumborum. The impact this selection has on the IMF% of other muscle depots is unknown. This study examined IMF% in five different muscles from 400 lambs (M. longissimus lumborum, Muscularis semimembranosus, Muscularis semitendinosus, Muscularis supraspinatus, Muscularis infraspinatus). The sires of these lambs had a broad range in carcass breeding values for post-weaning weight, eye muscle depth and fat depth over the 12th rib (c-site fat depth). Results showed IMF% to be highest in the M. supraspinatus (4.87±0.1, P<0.01) and lowest in the M. semimembranosus (3.58±0.1, P<0.01). Hot carcass weight was positively associated with IMF% of all muscles. Selection for decreasing c-site fat depth reduced IMF% in the M. longissimus lumborum, M. semimembranosus and M. semitendinosus. Higher breeding values for post-weaning weight and eye muscle depth increased and decreased IMF%, respectively, but only in the lambs born as multiples and raised as singles. For each per cent increase in lean meat yield percentage (LMY%), there was a reduction in IMF% of 0.16 in all five muscles examined. Given the drive within the lamb industry to improve LMY%, our results indicate the importance of continued monitoring of IMF% throughout the different carcass regions, given its importance for eating quality

Factors affecting lamb eating quality and the potential for their integration into an MSA sheepmeat grading model

Major efforts in the sheep industry to control eating quality have resulted in reduced product variability. Yet inconsistent eating quality for consumers remains, due to a degree of inaccurate representation of cut quality. Eating quality defined through a complex interplay of different factors can be predicted for individual cuts, and Meat Standards Australia (MSA) grading schemes have been developed to achieve these defined quality outcomes. This review outlines the justifications to refine the current sheepmeat MSA pathways system to transition into a cuts-based prediction model and details some of the factors affecting sheepmeat eating quality as key factors under consideration into the new model. The development of the new sheepmeat MSA prediction model will allow for more efficient carcass sorting to underpin a value based payment system throughout the supply chain. However it requires the inclusion of individual carcass yield and eating quality measurements (i.e. IMF). Furthermore, the adoption challenges internationally of an MSA like model are discussed

Lamb age has little impact on eating quality

There is an industry wide perception that new season lamb has better eating quality than old season lamb. This study aims to identify differences in consumer eating quality scores between two age classes in lamb. Consumer eating quality scores from eight cuts across the carcass were evaluated from new season (NS; n = 120; average age = 240 days) and old season lambs (OS; n = 121; average age = 328 days), sourced from four different flocks. Cuts were grilled (loin, topside, outside, knuckle and rump) or roasted (leg, shoulder, rack) and scored by untrained consumers for tenderness, juiciness, liking of flavour and overall liking. There was no difference in eating quality scores between the two age classes for the loin, leg, shoulder and rack. This was similarly shown in the topside with the exception of juiciness scores where NS lambs were higher than OS lambs. There was also a lack of age difference in the outside with the exception of flock 3 where NS lambs scored higher than OS lambs for all sensory traits. Across all sensory traits, OS lambs received on average 2.8 scores lower for the knuckle and 3.1 scores lower for the rump compared to NS lambs. These results show little difference in eating quality between NS and OS lamb, and highlight the potential to develop high quality OS or "autumn lamb" products, with a similar premium price at retail as NS lambs

Sire carcass breeding values affect body composition in lambs — 1. Effects on lean weight and its distribution within the carcass as measured by computed tomography

Data are obtained from computed tomography scanning of 1665 lambs at locations around Australia. Lambs were progeny of Terminal, Maternal and Merino sires with known Australian Sheep Breeding Values for post weaning c-site eye muscle depth (mm; PEMD) and fat depth (mm; PFAT), and post weaning weight (kg; PWWT). Across the 7.8 unit range of sire PEMD, carcass lean weight increased by 7.7%. This lean was distributed to the saddle section (mid-section) where lean became 3.8% heavier, with fore section lean becoming 3.5% lighter. Reducing sire PFAT across its 5.1 unit range increased carcass lean weight by 9.5%, and distributed lean to the saddle section which was 3.7% heavier. Increasing sire PWWT increased lean at some sites in some years, and on average increased saddle lean by 4% across the 24.7 unit PWWT range. Changes in lean weight and distribution due to selection for carcass breeding values will increase carcass value, particularly through increased weight of high value loin cuts

Regional and Hemispheric Determinants of Language Laterality: Implications for Preoperative fMRI

Language is typically a function of the left hemisphere but the right hemisphere is also essential in some healthy individuals and patients. This inter-subject variability necessitates the localization of language function, at the individual level, prior to neurosurgical intervention. Such assessments are typically made by comparing left and right hemisphere language function to determine “language lateralization” using clinical tests or fMRI. Here, we show that language function needs to be assessed at the region and hemisphere specific level, because laterality measures can be misleading. Using fMRI data from 82 healthy participants, we investigated the degree to which activation for a semantic word matching task was lateralized in 50 different brain regions and across the entire cortex. This revealed two novel findings. First, the degree to which language is lateralized across brain regions and between subjects was primarily driven by differences in right hemisphere activation rather than differences in left hemisphere activation. Second, we found that healthy subjects who have relatively high left lateralization in the angular gyrus also have relatively low left lateralization in the ventral precentral gyrus. These findings illustrate spatial heterogeneity in language lateralization that is lost when global laterality measures are considered. It is likely that the complex spatial variability we observed in healthy controls is more exaggerated in patients with brain damage. We therefore highlight the importance of investigating within hemisphere regional variations in fMRI activation, prior to neuro-surgical intervention, to determine how each hemisphere and each region contributes to language processing. Hum Brain Mapp, 2010. © 2010 Wiley-Liss, Inc

Selection for leanness decreases meat aerobicity

The Australian lamb industry uses Australian Sheep Breeding Values for reduced postweaning subcutaneous fat depth (PFAT) to select for leanness and increased lean meat yield. Selection for reduced PFAT results in increased loin muscle weight (Gardner et al 2010) potentially leading to lower oxidative capacity in muscle (Greenwood et al 2006). Isocitrate dehydrogenase activity (ICDH) is an accepted indicator of aerobic metabolism, and therefore we hypothesise that selection for reduced PFAT results in a decrease in ICDH levels

Motor Outcomes After Neonatal Arterial Ischemic Stroke Related to Early MRI Data in a Prospective Study

OBJECTIVE: We aimed to correlate early imaging data with motor outcomes in a large, homogeneous, cohort of infants with neonatal (diagnosed before 29 days of life) arterial ischemic stroke (AIS).METHODS: From a prospective cohort of 100 children with neonatal AIS, we analyzed the MRI studies performed within the 28 first days of life for 80 infants evaluated at 2 years of age. The relationships between infarction location and corticospinal tract (CST) involvement and motor outcomes were studied RESULTS: Seventy-three infarctions involved the middle cerebral artery (MCA) territory. Of those, 50 were superficial infarctions, 5 deep infarctions, and 18 mixed infarctions. The CST was involved in 24 cases. Nineteen patients with MCA infarctions (26% [95% confidence interval: 16%–34%]) developed hemiplegia. Mixed infarctions (P &lt; .0001) and CST involvement (P &lt; .0001) were highly predictive of hemiplegia. In contrast, 88% of children with isolated superficial MCA infarctions did not exhibit impairment. CONCLUSIONS: Accurate prediction of motor outcomes can be obtained from early MRI scans after neonatal AIS. The absence of involvement of the CST resulted in normal motor development in 94% of cases. CST involvement resulted in congenital hemiplegia in 66% of cases

Guidelines to engage with marginalized ethnic minorities in agricultural research for development in the Greater Mekong

This document is an output of Humidtropics, a CGIAR Research Program on Integrated Systems for the Humid Tropics. This document is designed to help researchers who want to engage with ethnic groups to ensure agricultural research for development (R4D) stops contributing to their further marginalization. It can be used by those wanting to design new projects that engage with ethnic minorities from the start or those already implementing projects and wanting to improve their current practice. Based on an analysis of internal and external factors that lead to marginalization of ethnic minority groups through agricultural R4D, the Guidelines are organized around three sets of challenges: (a) the agricultural R4D system as a whole; (b) for research teams; and (c) for agricultural R4D projects. The document identifies for each challenge strategies that can help prevent further marginalization according to different stages in the project cycle. The overall approach that these Guidelines recommend is transdisciplinary action research. The strategies are thus those that can help agricultural R4D researchers to carry out transdisciplinary action research that engages more effectively with marginalized ethnic minority groups in order to achieve more inclusive and equitable rural development from agriculture

Atlas-Free Surface Reconstruction of the Cortical Grey-White Interface in Infants

BACKGROUND: The segmentation of the cortical interface between grey and white matter in magnetic resonance images (MRI) is highly challenging during the first post-natal year. First, the heterogeneous brain maturation creates important intensity fluctuations across regions. Second, the cortical ribbon is highly folded creating complex shapes. Finally, the low tissue contrast and partial volume effects hamper cortex edge detection in parts of the brain. METHODS AND FINDINGS: We present an atlas-free method for segmenting the grey-white matter interface of infant brains in T2-weighted (T2w) images. We used a broad characterization of tissue using features based not only on local contrast but also on geometric properties. Furthermore, inaccuracies in localization were reduced by the convergence of two evolving surfaces located on each side of the inner cortical surface. Our method has been applied to eleven brains of one- to four-month-old infants. Both quantitative validations against manual segmentations and sulcal landmarks demonstrated good performance for infants younger than two months old. Inaccuracies in surface reconstruction increased with age in specific brain regions where the tissue contrast decreased with maturation, such as in the central region. CONCLUSIONS: We presented a new segmentation method which achieved good to very good performance at the grey-white matter interface depending on the infant age. This method should reduce manual intervention and could be applied to pathological brains since it does not require any brain atlas

Carcass characteristics and beef quality of young grass-fed Angus x Salers bovines

To characterize carcass and meat attributes, such as beef eating quality in specific farming conditions, 31 young grass-fed crossbred Angus x Salers cattle in two farming systems (a mono-cattle system versus a mixed system with beef cattle and sheep) were used in this study. Three muscle cuts (striploin—m. longissimus dorsi et thoracis; bolar blade—m. triceps brachii caput longum; internal flank plate—m. obliquus internus abdominis) were used for consumer eating quality testing and striploin was used for panelist eating quality assessment, and objective measurements [Warner–Bratzler shear force (WBSF) and fatty acid (FA) and antioxidant contents]. Results indicated that the farming system had no impact on carcass characteristics or meat quality, but it tended to affect FA content, which is likely explained by between-system differences in animal maturity (assessed by ossification score). Animal gender had significant effects on three eating quality traits evaluated by untrained consumers, with higher flavor liking, overall liking, and overall meat eating quality (MQ4) scores in females than in males. Additionally, FA contents were correlated with sensory quality traits to varying extents: consumer-scored tenderness, flavor, and overall liking were mainly positively correlated with ω-3 and ω-6 polyunsaturated fatty acid (PUFA) contents, and panelist-evaluated tenderness and abnormal flavor were more positively correlated with total lipids, saturated fatty acid (SFA), and monounsaturated fatty acid (MUFA) contents. Overall, this study showed that specific grass-fed crossbred Angus x Salers cattle can produce lean meat rich in ω-3 PUFAs with a low ω-6/ω-3 ratio and with “better than average” beef eating quality