ORCID Profile
0000-0002-4877-3112
Current Organisations
Murdoch University
,
University of Oxford
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Publisher: Wiley
Date: 11-2007
Publisher: Springer Science and Business Media LLC
Date: 09-04-2017
Publisher: Wiley
Date: 16-10-2020
DOI: 10.1002/AR.24530
Abstract: Polydactyly is a congenital malformation resulting from an autosomal dominant mutation manifesting as supernumerary digits of the hands or feet. It is most commonly reported in humans and domestic mammals, though there have also been isolated ex les across a range of wild vertebrate species. Here we report a case of extremely unusual bilateral preaxial polydactyly on the pectoral limbs of a male western grey kangaroo ( Macropus fuliginosus ) from the South West region of Western Australia, in which two supernumerary digits were present on each manus. A supernumerary digit I on each manus was rudimentary in morphology without extrinsic muscular connections. However, supernumerary digit II present on each manus had fully developed extrinsic and intrinsic muscular connections, suggesting that these digits possessed normal function in flexion and extension. An alternative hypothesis is that the two supernumerary digits are both representatives of the most radial digit I, though this would then require the true digit I to have taken on the appearance of digit II by acquiring an additional phalanx and modified muscular attachments. The carpal bones exhibited a number of subtle differences in morphology when compared to normal pentadactyl in iduals. The presence of a distal, rather than proximal, epiphysis on the first metacarpal was unexpected but further investigation suggested that this characteristic is perhaps more variable (in this species at least) than has been previously recognized. This case provides an unusual ex le to be considered within the broader context of limb development.
Publisher: MDPI AG
Date: 17-02-2022
DOI: 10.3390/ANI12040501
Abstract: Lamb growth can be optimised with genetic selection using sire Australian sheep breeding values, however, breeding value expression has been shown to be reduced with poor nutrition. It was therefore hypothesised that the genetic potential for lamb growth would also be reduced, where production factors such as multiple births limit growth. Live weights at birth, weaning, and post-weaning were collected from more than 18,000 lambs produced over five years and eight locations of the Sheep Cooperative Research Centre Information Nucleus Flock experiment, and the impact of environment, production factors, and genotype was determined using mixed effects regression. The genetic potential for lamb growth was moderated by environment, multiple births, and sire type (p 0.05). Twin lambs achieved 76% of the expected weight gain at weaning and 58% post-weaning. For triplet lambs weight gains were drastically less at approximately 30% of the expected gain at the same time points. Lambs born to maternal sires consistently had the poorest response to genetic selection, achieving approximately half the expected weight gain. Hence, producers need to temper expectations for growth based on genetic selection, or employ mitigation strategies such as precision feeding, the use of alternate breeds, or place emphasis on the genetic merit of other desirable traits.
Publisher: Elsevier BV
Date: 11-2019
DOI: 10.1016/J.FOODRES.2019.108528
Abstract: This study investigated the effect of three ageing methods (dry, wet and stepwise wet-then-dry) and ageing time on pH, colour, yield, lipid and protein oxidation and eating quality of beef loins using Meat Standards Australia (MSA) sensory protocols with 900 and 540 consumers in Australia and Japan, respectively. Australian beef loins (Longissimus thoracis et lumborum) at four days post mortem were subjected to wet ageing (boneless for 7, 21, 35 or 56 days), dry ageing (bone-in for 35 or 56 days) or a wet-then-dry ageing method (bone-in 21 days wet ageing followed by 35 days dry ageing). The pH was higher in dry aged than wet aged beef loins (P < .001). Instrumental measurement of surface colour of trimmed dry and wet aged steaks showed significant differences in a*, b* and hue angle. Weight loss was higher in dry aged primals (P < .001), however, total water content was similar among the two ageing methods (P = .934). Retail yield did not differ between 35 and 56 days dry aged primals. Lipid (TBARS) and protein (total carbonyl content) oxidation between the dry and wet aged s les differed depending on the ageing time. When comparing the wet-then-dry and 56 days dry aged s les, only pH and retail yield differed. Australian and Japanese consumers rated dry aged steaks significantly higher (P < .001) than the wet aged counterparts for tenderness, juiciness, flavour, overall liking and weighted palatability scores. The wet-then-dry steaks were also rated higher than the 56 days wet aged steaks for flavour, overall liking and palatability within the Japanese sensory panels. The Japanese consumers also consistently rated all MSA sensory attributes lower (P < .001) than the Australian consumers. The results from this study show dry ageing provides a value adding opportunity for the meat industry in both domestic and export markets.
Publisher: Elsevier BV
Date: 02-2014
DOI: 10.1016/J.MEATSCI.2013.08.017
Abstract: Selection for increased lean meat yield using Australian Sheep Breeding Values for reduced post-weaning c-site fat depth (PFAT) and increased post-weaning eye muscle depth (PEMD) reduces the oxidative capacity of muscle. Isocitrate dehydrogenase (ICDH) activity and myoglobin concentration were measured in 3178 and 5580 lambs, respectively, to indicate oxidative capacity. In the progeny of sires with a reduced PFAT, ICDH activity and myoglobin concentration were reduced by 0.46 μmol/min/g tissue and 0.67 mg/g tissue across the 5 and 6mm PFAT ranges respectively. In the progeny of sires with an increased PEMD, ICDH activity and myoglobin concentration were reduced by 0.50 μmol/min/g tissue and 0.49 mg/g tissue across the 7 and 6 mm PEMD ranges respectively. However, the sites at which the lambs were raised had a larger impact on oxidative capacity than genetic or other production factors.
Publisher: Elsevier BV
Date: 2019
Publisher: Magnolia Press
Date: 07-06-2023
DOI: 10.11646/ZOOTAXA.5299.1.1
Abstract: Tree-kangaroos of the genus Dendrolagus occupy forest habitats of New Guinea and extreme northeastern Australia, but their evolutionary history is poorly known. Descriptions in the 2000s of near-complete Pleistocene skeletons belonging to larger-bodied species in the now-extinct genus Bohra broadened our understanding of morphological variation in the group and have since helped us to identify unassigned fossils in museum collections, as well as to reassign species previously placed in other genera. Here we describe these fossils and analyse tree-kangaroo systematics via comparative osteology. Including B. planei sp. nov., B. bandharr comb. nov. and B. bila comb. nov., we recognise the existence of at least seven late Cenozoic species of Bohra, with a maximum of three in any one assemblage. All tree-kangaroos (Dendrolagina subtribe nov.) exhibit skeletal adaptations reflective of greater joint flexibility and manoeuvrability, particularly in the hindlimb, compared with other macropodids. The Pliocene species of Bohra retained the stepped calcaneocuboid articulation characteristic of ground-dwelling macropodids, but this became smoothed to allow greater hindfoot rotation in the later species of Bohra and in Dendrolagus. Tree-kangaroo ersification may have been tied to the expansion of forest habitats in the early Pliocene. Following the onset of late Pliocene aridity, some tree-kangaroo species took advantage of the consequent spread of more open habitats, becoming among the largest late Cenozoic tree-dwellers on the continent. Arboreal Old World primates and late Quaternary lemurs may be the closest ecological analogues to the species of Bohra.
Publisher: Elsevier BV
Date: 11-2021
Publisher: MDPI AG
Date: 05-03-2021
Abstract: Lamb (n = 79) meat colour was scored by 879 untrained consumers using a scale of 0 (brown) to 100 (red). This consumer colour score (CCS) was obtained on m. longissimus lumborum (loin) and m. semimembranosus (topside), stored for short (5–7 days), medium (33–35 days), and long periods (110–112 days) and a retail display time of up to 4 days. Consumers perceived topside to be less red initially and changed from red to brown more rapidly when stored for the long-storage period (p 0.01). Whereas, the initial CCS of loin s les were similar across the storage periods (p 0.05). CCS and the instrument measure oxy/met (reflectance of light at wavelengths 630 nm and 580 nm) had a low correlation coefficient of 0.33 (p 0.01). The propensity for lamb growth and leanness indicated by sire breeding values for lamb weight, eye muscle depth, eye muscle fat depth, and loin intramuscular fat had varied and inconsistent effects on CCS. Therefore, even the selection on CCS.
Publisher: Springer Science and Business Media LLC
Date: 14-05-2016
Publisher: Elsevier BV
Date: 2020
Publisher: MDPI AG
Date: 07-2022
DOI: 10.3390/ANI12131707
Abstract: Ewes often lamb over extended periods so the level of nutrition during pregnancy and lambing may be suboptimal for ewes that conceived later during mating. Predicting lambing dates would allow cohorts of ewes with similar gestational ages to be managed more precisely to achieve targets for ewe nutrition, feed on offer, mob sizes and access to shelter to improve lamb survival. The interactions between ewes and rams during mating have been used to predict the time of oestrus and lambing dates successfully, but this has not been tested at a commercial scale. In this study, proximity sensors were used to measure interactions between inexperienced Merino ewes (n = 317) and experienced rams (n = 9) during a 27-day mating period under commercial production conditions. When the gestation length was assumed to be 150 days, 91% of lambing dates were predicted within ±6 days of the actual birth date of lambs and 84% of lambing dates were predicted within ±3 days. The use of proximity sensors during mating was an effective means of predicting lambing dates, and there was no significant difference in accuracy for single bearing verses multiple bearing ewes. However, DNA parentage data showed the ram corresponding with the maximum daily interactions ratio was the sire for only 16% of all progeny, suggesting they could not be used to indicate the sire of the progeny.
Location: United Kingdom of Great Britain and Northern Ireland
No related grants have been discovered for Khama Kelman.