Additive Impacts of Liveweight and Body Condition Score at Breeding on the Reproductive Performance of Merino and Non-Merino Ewe Lambs.

Ewe lambs that are heavier due to improved nutrition pre- and post-weaning achieve puberty at a younger age, are more fertile, and have a higher reproductive rate. Fatness is intimately linked to reproduction, and we hypothesised that higher body condition scores at breeding would have positive effects on the reproductive rate of ewe lambs over and above liveweight. We also expected that if only a proportion of ewe lambs were presented for breeding, then it would be more effective to select them based on both liveweight and body condition score. To test these hypotheses, we analysed data from over 17,000 records from Merino and non-Merino ewe lambs from 22 different flocks across Australia. Non-Merino ewe lambs were more fertile (69.4% vs. 48.7%) and achieved a higher reproductive rate than Merino ewe lambs (96.9% vs. 60.7%). There were significant curvilinear relationships between liveweight (p < 0.001) or body condition score (p < 0.001) prior to breeding and reproductive rate for both Merino and non-Merino ewe lambs. For both breeds, there was a significant (p < 0.001) quadratic effect of body condition score prior to breeding on reproductive rate, independent of the correlated changes in liveweight, and at the same liveweight, an extra 0.5 of a body condition score up to 3.3 improved reproductive rate by about 20%. Nevertheless, the results indicated that if only a proportion of ewe lambs were selected for breeding, then selection based on both liveweight and body condition scores may only improve the overall reproductive rate by 1 to 2% compared to selection based on liveweight alone. We conclude that liveweight is a more effective method than body condition score for selecting ewe lambs for breeding.

Management of Body Condition Score between Pregnancy Scanning and Lamb Marking Impacts the Survival of Triplet-Bearing Ewes and Their Lambs.

This study evaluated the impacts of management of body condition score (BCS) between pregnancy scanning and lamb marking on the mortality of triplet-bearing ewes and their lambs at 19 research sites across Southern Australia. Triplet-bearing ewes of Maternal (crossbred or composite) or Merino breed were randomly allocated to treatment at pregnancy scanning at an average of 97 days from the start of joining: High or Low BCS. The BCS of individual ewes was assessed at pregnancy scanning, pre-lambing (average of 137 days from the start of joining) and marking (average of 165 days from the end of joining), and ewe and lamb mortality to marking, recorded for each mob. The average BCS at pregnancy scanning was 3.4 for Maternal ewes and 3.3 for Merino ewes. There were no breed by BCS treatment effects on the BCS of ewes at pregnancy scanning or lamb marking or on the change in BCS between pregnancy scanning and pre-lambing or between pre-lambing and marking. The change in BCS differed between the High and Low BCS treatments, between pregnancy scanning and pre-lambing (0.12 vs. -0.33; p < 0.001) and between pre-lambing and marking (-0.39 vs. 0.07; p < 0.001) but did not differ between breeds. The average BCS at marking for ewes managed at the High and Low BCS treatments was 3.1 and 3.0 for Maternals and 3.0 and 2.8 for Merinos. Survival of triplet-bearing Merino ewes (p < 0.01) and their lambs (p < 0.001) was greater when ewes were managed at the High BCS compared to the Low BCS. The BCS treatment did not impact the survival of Maternal ewes or their lambs. The survival of Merino but not Maternal lambs was higher when ewes were in greater BCS pre-lambing (p < 0.01) and when ewes gained BCS between pregnancy scanning and pre-lambing (p < 0.01). Ewe mortality was lower when ewes gained BCS between pregnancy scanning and pre-lambing (p < 0.05). Merino ewes were more likely to die than Maternal ewes for a given change in BCS between pregnancy scanning and pre-lambing (p = 0.065). Overall, our findings demonstrate that producers should manage the nutrition of triplet-bearing Merino ewes so that ewes are in greater BCS at lambing and/or to gain BCS between pregnancy scanning and lambing to improve ewe and lamb survival. Triplet-bearing Maternal ewes should be managed to gain BCS between pregnancy scanning and lambing to improve ewe survival.

Decreasing Mob Size at Lambing Increases the Survival of Triplet Lambs Born on Farms across Southern Australia.

Industry consultation in Australia revealed that the potential impact of the mob size of ewes during lambing on the survival of triplet-born lambs was an important research priority. Previous research has demonstrated that smaller mob sizes at lambing improve the survival of single- and especially twin-born lambs, regardless of ewe stocking rate. Therefore, we hypothesised that lambing triplet-bearing ewes in smaller mobs, regardless of stocking rate, will increase the survival of their lambs. Research sites were established on 12 commercial sheep farms across southern Australia between 2019 and 2021. One farm used Merinos whilst the remainder of the farms used non-Merino breeds, consisting of composite ewes joined to composite or terminal sires. Three of the farms were used in two years of the experiment. Adult, triplet-bearing ewes were randomly allocated into one of two treatments, 'High' or 'Low' mob size, at an average of 135 days from the start of joining. Ewe and lamb survival were assessed between allocation to treatments and lamb marking. Lamb survival was significantly greater for lambs born in the Low (65.6%) compared with the High (56.6%) mob size treatments (p < 0.001). There was no effect of mob size at lambing on the mortality of triplet-bearing ewes. Analysis of the effect of the actual mob sizes showed that reducing the mob size at lambing by 10 triplet-bearing ewes increased the survival of their lambs to marking by 1.5% (p < 0.001). This study has shown that the survival of triplet-born lambs can be improved by lambing triplet-bearing ewes in smaller mobs regardless of stocking rate when ranging from 0.7-13 ewes/ha.

Reproductive Performance of Triplet-Bearing Ewes on Commercial Farms and Research Priorities Identified by Sheep Producers to Improve the Survival of Triplet-Bearing Ewes and Their Lambs.

Consultation with sheep producers was used to quantify the mortality of triplet-bearing ewes and their lambs, identify management practices adopted by producers to reduce these losses and prioritise future research needs to improve the survival of triplet-bearing ewes and their lambs. Surveys were completed by 64 producers across Australia who identified and separated triplet-bearing ewes from twin-bearing ewes in 2017 and/or 2018. On average, 5.9% of all ewes mated were identified as carrying triplets (6.6% of non-Merino ewes and 2.9% of Merino ewes). The average mortality of triplet-bearing ewes was 6.4%, and ewe mortality did not differ significantly between ewe breeds. The average survival of triplet-born lambs was 59%, and survival was significantly higher for lambs from non-Merino compared to Merino ewes (60.1 vs. 52.9%, p < 0.05). The key strategies adopted to reduce the mortality of triplet-bearing ewes and their lambs included management of condition score, feed-on-offer, mob size at lambing and use of shelter. There were no differences (p > 0.05) in the average mortality of triplet-bearing ewes or their lambs between producers that prioritised the adoption of certain management practices. However, significant variation existed between producers in their targets at lambing for ewe condition score (2.8 to 3.5), mob size (10 to 150 ewes) and feed-on-offer (800 to 2500 kg dry matter/ha). Overwhelmingly, the highest priorities for further research identified by producers from surveys, workshops and a webinar were ewe condition score, mob size, feed-on-offer at lambing and mineral supplementation. This study informs benchmarks for mortality of triplet-bearing ewes and their lambs under extensive grazing conditions in Australia, and the priorities for future research to reduce these losses.

The Use of Binaural Based Spatial Audio in the Reduction of Auditory Hypersensitivity in Autistic Young People.

Individuals diagnosed with autism spectrum disorder (ASD) are characterised as experiencing impairments in social-emotional interaction and communication, alongside frequently displaying repetitive behaviours and interests. Further to this, they are often described as experiencing difficulties in processing sensory information, with particular prevalence within the auditory modality. Provoked by common environmental sounds, auditory hypersensitivity can result in self-regulatory fear responses. Rather than a physiological pain reaction, literature suggests that these hypersensitivities are resulting through irrational fear of the sounds. This investigation evaluates the use of binaural based spatial audio as a rendering technique for delivering realistic simulations of averse stimuli within a virtual reality (VR) exposure based computer game intervention for auditory hypersensitivity in autism. Over multiple experimental sessions, 20 autistic participants experiencing auditory hypersensitivity were exposed to either spatial audio or stereo renders of target stimuli during the intervention. Measurements of self-reported emotions displayed significant reductions in associated negative emotional reactions to target stimuli for all participants. However, significant improvements were experienced by those listening to spatial audio simulations. Moreover, tracked voluntary interactions with exposure based game-mechanics increased as the study progressed. Providing further evidence of increased tolerance towards averse auditory stimuli.

The Number of Offspring Weaned from Ewe Lambs Is Affected Differently by Liveweight and Age at Breeding.

In this paper, we tested the hypothesis that ewe lambs that are heavier and older at breeding will wean more offspring, due to increased reproductive rate and offspring survival and lower maternal mortality. To test this hypothesis, we analyzed data from more than 11,500 maternal composite ewe lambs collected over eight years. The ewe lambs had full pedigree records including birth type, age and liveweight at breeding plus records of the birthweight and survival of their offspring and the dam. The average liveweight and age at breeding was 40.2 kg and 228 days. The reproductive rate and weaning rate responses to liveweight at breeding were curvilinear (p < 0.001), and if ewe lambs achieved 45 kg by the start of breeding, their reproductive rate and weaning rate were within 5% of their maximum. By contrast, the effects of age at breeding on weaning rate was linear and increased by 0.4% per day, despite a quadratic (p < 0.01) effect of age at breeding on reproductive rate which increased only marginally when ewe lambs were older than 8 months at breeding. Increasing liveweight (p < 0.05) or age (p < 0.001) at breeding increased survival of their offspring, however an extra 10 kg of liveweight or 30 days of age at breeding increased offspring survival by less than 5%. Both liveweight (p < 0.001) and age (p < 0.01) at breeding also influenced survival of the ewe lamb dam but survival rates exceeded 95% across the range in liveweights from 30 to 55 kg and ages from 6 to 9 months. This understanding of the trade-off between age and liveweight at breeding will assist farmers to optimize the management of their ewe lambs, given the earlier they can be bred successfully the easier they can be integrated with the breeding of the adult ewe flock the following year.

Abortion and Lamb Mortality between Pregnancy Scanning and Lamb Marking for Maiden Ewes in Southern Australia.

The contribution of abortions to the overall mortality of lambs born to maiden (primiparous) ewes in Australia remains unclear. This cohort study aimed to quantify abortion and lamb mortality for ewe lambs and maiden Merino two-tooth ewes. Lamb mortality from pregnancy scanning to marking were determined for 19 ewe lamb and 11 Merino two-tooth ewe flocks across southern Australia. Average lamb mortality from scanning to marking was 35.8% (range 14.3-71.1%) for the ewe lambs and 29.4% (range 19.7-52.7%) for the two-tooth ewes. Mid-pregnancy abortion was detected in 5.7% of ewes (range 0-50%) in the ewe lamb flocks and 0.9% of ewes (range 0-4.4%) in the two-tooth ewe flocks. Mid-pregnancy abortion affecting ≥2% of ewes was observed in 6/19 ewe lamb flocks and 2/11 two-tooth ewe flocks. Lamb mortality from birth to marking represented the greatest contributor to foetal and lamb mortality after scanning, but mid-pregnancy abortion was an important contributor to lamb mortality in some ewe lamb flocks. Variability between the flocks indicates scope to improve the overall reproductive performance for maiden ewes by reducing foetal and lamb losses. Addressing mid-pregnancy abortion may improve the reproductive performance in some flocks.

Ageing and cathepsin inhibition affect the shrinkage of fibre fragments of bovine semitendinosus, biceps femoris and psoas major during heating.

This study examines the effects of ageing (1, 14 days), cathepsin inhibition (No or Yes) and temperature (25-90 °C) on the shrinkage of fibre fragments from three bovine muscles (semitendinosus, biceps femoris and psoas major) during heating. Shrinkage was quantified using light microscopy images. Muscle fibres (except in psoas major) had greater transverse shrinkage, and less longitudinal shrinkage in aged than in unaged muscles at temperatures ≥60-75 °C. In addition, cathepsin inhibition during heating at ≥65-90 °C caused greater transverse shrinkage in semitendinosus fibres, and reduced longitudinal shrinkage for all muscles. At temperatures ≥75 °C, the longitudinal and transverse shrinkage of the fibres was correlated for all muscles. Ageing of biceps femoris increases volume shrinkage on a fibre level, and hence potentially cooking loss, while cathepsin activity in the semitendinosus reduces volume shrinkage. In conclusion, cathepsin activity and ageing influence the shrinkage that occurs during heating and these factors should be explored further to enable optimisation of thermal meat processing.

Technical note: validation of an automated feeding system for measuring individual animal feed intake in sheep housed in groups.

The development of feeding systems that can individually measure and control feed intake in a group-housed environment would allow a greater understanding of sheep intake without compromising animal welfare and behavior through the removal of social interactions between sheep. This study validated an automated feeding system for measuring feed intake of individual sheep when housed in groups. Validation of the feeding system was conducted during three separate experiments. The validation sampling involved the activation of four individual "feed events," whereby four separate samples weighing approximately 50, 100, 200, and 400 g were removed from each feeder, with each feed event being linked to a specific radio frequency identification (RFID) tag. The feeder validation experiments evaluated the ability of the feeding system to 1) create a unique feed event every time a sample of pellets was collected from the feeder, 2) link the feed event to the correct RFID, and 3) accurately record the weight of feed that was manually removed. All feed events were initiated and logged in the feeding system with 100% of the events being linked to the correct test RFID. Concordance correlation coefficients between the feeding system-recorded feed weight and the manually removed weight were 0.99 within all three experiments. There was also no overall and little level-dependent bias between the weights measured by the feeding system and weights measured on the external scales. These results indicate the stability of the feeding system over time and consistency between the feeders within and across the three experiments. In conclusion, the automated feeding system developed for measuring individual animal feed intake was able to detect and record the unique electronic RFID associated with unique feed events and accurately capture the weight of feed removed. Furthermore, there was no change in the accuracy of the system from the start to the end of experimental periods, and the amount of feed removed in the feed event (or meal size) did not impact the accuracy of the results.

Evaluation of endophyte toxin production and its interaction with transgenic perennial ryegrass (Lolium perenne L.) with altered expression of fructosyltransferases.

Alkaloid concentration of perennial ryegrass herbage is affected by endophyte strain and host plant genotype. However, previous studies suggest that associations between host and endophyte also depends on environmental conditions, especially those affecting nutrient reserves and that water-soluble carbohydrate (WSC) concentration of perennial ryegrass plants may influence grass-endophyte associations. In this study a single transgenic event, with altered expression of fructosyltransferase genes to produce high WSC and biomass, has been crossed into a range of cultivar backgrounds with varying Epichloë endophyte strains. The effect of the association between the transgenic trait and alkaloid production was assessed and compared with transgene free control populations. In the vast-majority of comparisons there was no significant difference between alkaloid concentrations of transgenic and non-transgenic plants within the same cultivar and endophyte backgrounds. There was no significant difference between GOI+ (gene of interest positive) and GOI- (gene of interest negative) populations in Janthritrem response. Peramine concentration was not different between GOI+ and GOI- for 10 of the 12 endophytes-cultivar combinations. Cultivar Trojan infected with NEA6 and Alto with SE (standard endophyte) exhibited higher peramine and lolitrem B (only for Alto SE) concentration, in the control GOI- compared with GOI+. Similarly, cultivar Trojan infected with NEA6 and Alto with NEA3 presented higher ergovaline concentration in GOI-. Differences in alkaloid concentration may be attributable to an indirect effect in the modulation of fungal biomass. These results conclude that the presence of this transgenic insertion, does not alter the risk (toxicity) of the endophyte-grass associations. Endophyte-host interactions are complex and further research into associations with high WSC plant should be performed in a case by case basis.

The sound of the crowd: auditory information modulates the perceived emotion of a crowd based on bodily expressions.

Although both auditory and visual information can influence the perceived emotion of an individual, how these modalities contribute to the perceived emotion of a crowd of characters was hitherto unknown. Here, we manipulated the ambiguity of the emotion of either a visual or auditory crowd of characters by varying the proportions of characters expressing one of two emotional states. Using an intersensory bias paradigm, unambiguous emotional information from an unattended modality was presented while participants determined the emotion of a crowd in an attended, but different, modality. We found that emotional information in an unattended modality can disambiguate the perceived emotion of a crowd. Moreover, the size of the crowd had little effect on these crossmodal influences. The role of audiovisual information appears to be similar in perceiving emotion from individuals or crowds. Our findings provide novel insights into the role of multisensory influences on the perception of social information from crowds of individuals.

Identification of QTLs for morphological traits influencing waterlogging tolerance in perennial ryegrass (Lolium perenne L.).

Perennial ryegrass is a globally cultivated obligate outbreeding diploid species (2n = 2x = 14) which is subjected to periods of waterlogging stress due to flood irrigation during winter and the lead-up to summer. Reduction of oxygen supply to root systems due to waterlogging produces consequent deleterious effects on plant performance. Framework genetic maps for a large-scale genetic mapping family [F1(NA(x) × AU6)] were constructed containing 91 simple sequence repeat and 24 single nucleotide polymorphism genetic markers. Genetic trait dissection using both control and waterlogging treatments was performed in the glasshouse, a total of 143 maximally recombinant genotypes being selected from the overall sib-ship and replicated threefold in the trial. Analysis was performed for nine quantitative morphological traits measured 8 weeks after stress treatments were applied. A total of 37 quantitative trait loci (QTLs) were identified; 19 on the NA(x) parental genetic map, and 18 on the AU6 parental genetic map. Regions of particular interest were identified on linkage groups (LGs) 4 and 3 of the respective maps, which have been targeted for further analysis by selection of critical recombinants. This first study of genetic control of waterlogging tolerance in ryegrasses has important implications for breeding improvement of abiotic stress adaptation.

Identification of genetic factors influencing salt stress tolerance in white clover (Trifolium repens L.) by QTL analysis.

Allotetraploid (2n = 4x = 32) white clover (Trifolium repens L.) is the most commonly cultivated legume component of temperate pastures, sown in swards with a companion grass species. Genetic control of growth performance of white clover on saline land is highly important for dairy industries, due to increasing soil salinity problems. The objective of this study was to identify quantitative trait loci (QTLs) for salinity tolerance in terms of vegetative growth under stress. Two parental genetic maps consisting of 213 and 159 marker loci and spanning 1,973.0 and 1,837.6 cM, respectively, were constructed using simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers from a two-way pseudo-test cross F(1) population derived from pair-crossing of the Haifa(2) and LCL(2) genotypes. A total of 8 unique genomic regions on 8 linkage groups (LGs) of the Haifa(2) parental map and 6 unique regions on 5 LGs in the LCL(2) parental map were associated with plant growth under salt stress and relative growth under stress, as compared to control conditions. The results of this study indicate that salt tolerance in white clover is controlled by multiple QTLs, some at common locations, but each of limited magnitude. Location of these QTLs provides the genetic basis and potential for pyramiding of salt tolerance genes in breeding improvement.