Academic literature on the topic 'Limnology Victoria Bacchus Marsh'

Abstract The effects of past glaciation in what is now Australian territory were first recognized on Macquarie Island, probably by David Ramsay, in 1821. The recognition by Darwin in 1836, and reporting by Milligan in 1848 of ice-transported pebbles and boulders in late Palaeozoic marine rocks in Tasmania, showed on the one hand participation in and on the other familiarity with the controversy in Great Britain at that time on the origin of erratics and drift currents. Reports by Clarke (1852), Daintree in 1859, Selwyn (1860), and Gould (1860) of the effects of land ice on Mount Koscuisko (New South Wales), Bacchus Marsh (Victoria), Inman Valley (South Australia), and the Central Highlands (Tasmania), respectively, reflect the increasing recognition in Great Britain of the erosional and depositional effects of glaciers. Daintree, Selwyn, and Gould were all closely connected with A.C. Ramsay, the main British protagonist of the glacial theory at the time, whereas David Ramsay and Milligan were probably influenced by Robert Jameson of Edinburgh.

AbstractThe effects of past glaciation in what is now Australian territory were first recognized on Macquarie Island, probably by David Ramsay, in 1821. The recognition by Darwin in 1836, and reporting by Milligan in 1848 of ice-transported pebbles and boulders in late Palaeozoic marine rocks in Tasmania, showed on the one hand participation in and on the other familiarity with the controversy in Great Britain at that time on the origin of erratics and drift currents. Reports by Clarke (1852), Daintree in 1859, Selwyn (1860), and Gould (1860) of the effects of land ice on Mount Koscuisko (New South Wales), Bacchus Marsh (Victoria), Inman Valley (South Australia), and the Central Highlands (Tasmania), respectively, reflect the increasing recognition in Great Britain of the erosional and depositional effects of glaciers. Daintree, Selwyn, and Gould were all closely connected with A.C. Ramsay, the main British protagonist of the glacial theory at the time, whereas David Ramsay and Milligan were probably influenced by Robert Jameson of Edinburgh.

Leaf collections made from Lenses A and B of Pit II at the Eocene Alcoa Anglesea locality produced the first Eocene record of mummified leaves of the Myrtaceae. In order to determine their diversity and affinities a set of 19 architectural and cuticular characters was selected with which to analyse the leaves. This character set was tested with 65 extant leaves from 11 species of six genera within the Myrtaceae. Operational taxonomic units were analysed using a semi-Euclidian distance metric and the UPGMA clustering algorithm. Results indicated that the character set and analyses successfully clustered all members of each species used, and in the case of Syzygium loosely clustered most species of the genus that were tested. When applied to 34 fossil Myrtaceae leaves, the character sets and analyses revealed that two distinct fossil leaf taxa were present. The organ genus Myrtaciphyllum Christophel & Lys is proposed for mummified leaves with affinities to the Myrtaceae. Two species are erected: the type species M. undulatum, and M. douglasii. The two species are primarily differentiated on cuticular features. The analyses further showed that, in addition to the two fossil groups being distinct from each other, neither demonstrated close affinities with any of the 11 species of extant Myrtaceae used in the analysis. Two fossil Myrtaceae leaves included from the Miocene Bacchus Marsh locality showed moderate affinity to Myrtaciphyllum undulatum.

The Newer Volcanic Province (NVP) in Victoria, with extension into south-eastern South Australia, represents the youngest chapter of Cenozoic volcanism in south-eastern Australia. However, most ages have been determined by the potassium–argon (K–Ar) method, and the age data are not comprehensive. In addition, few ages exist for the array of scoria cone volcanoes in the NVP. Seven alkali feldspar samples, mostly anorthoclase megacrysts, from volcanic centres in the NVP were used for 40Ar/39Ar dating in the present study. In geochronological order, with ages quoting 95% confidence limits, locations are Mount Franklin near Daylesford (0.110 ± 0.014 Ma), Red Rock near Alvie (0.116 ± 0.048 Ma), Lake Bullenmerri at Camperdown (0.116 ± 0.019 Ma), Ridge Road Quarry near Daylesford (2.01 ± 0.11 Ma) and Mount Kororoit near Diggers Rest (3.74 ± 0.26 Ma). Two samples from The Anakies, near Bacchus Marsh, produced discordant results suggesting a maximum age of ca. 1.9 Ma. The analyses and reported ages in the present study not only provide new geochronological data for the province, but also elucidate the difficulties in dating very young basalts using the 40Ar/39Ar dating method. These results are consistent with the erosion levels of the scoria volcanoes sampled, and indicate a major episode of explosive volcanic activity at ca. 100 ka. In contrast, the more eroded Mount Kororoit is considered to be ca. 3.7 Ma in age. The age of The Anakies is more equivocal owing to the indicated presence of excess argon and a maximum age of ca. 1.9 Ma is suggested for this locality. Given the latter results and lack of precision obtainable from the younger samples, the possibility remains that other samples contained extraneous argon and that the ages generated are thus maximum eruption ages. Analyses of additional samples from these and other localities will be required to further resolve this issue.

Estrous synchronization (ES) protocols for fixed-time AI (FTAI) have been mainly developed for Bos taurus cattle assuming that usage in Bos indicus cattle results in similar outcomes. Unexplained variation in the reproductive outcomes of these treatments in extensively managed Bos indicus herds has limited the adoption of FTAI. The aim was to evaluate the ovarian function in heifers treated with different doses of progesterone (P4). Brahman (n = 30) and Brahman-cross (n = 34; 3/4 to 7/8 Brahman) heifers weighing an average of 285 kg (248 to 323 kg) and 307 kg (250 to 363 kg), respectively, were allocated at random to 1 of 4 treatment groups: 1) full-dose Cue-Mate (CM100; two P4-impregnated pods, 1.56 g of P4; Bioniche Animal Health Aust/Asia, Armidale, NSW, Australia; n = 17); 2) half-dose Cue-Mate (CM50; one P4-impregnated pod; 0.78 g of P4; n = 15); 3) half-dose Cue-Mate + 300IU of eCG (CM50+G; Pregnecol, Bioniche Animal Health, Aust/Asia; n = 14) i.m. at Cue-Mate removal; and 4) double PGF2α group (PG; n = 18). Heifers in the P4-treated groups received 1 mg of EB (estradiol benzoate; Ciderol; 1 mg mL-1; Genetics Australia, Bacchus Marsh, Victoria) at Cue-Mate insertion (Day -10) and 24 h after Cue-Mate removal (Day -1) and 250 μg of PGF2α (Cloprostenol, Estromil, Ilium Veterinary Products, Smithfield, Australia) i.m. at Cue-Mate insertion (Day -10) and removal (Day -2). Heifers in the PG group received 500 μg of PGF2α on Day -16 and Day -2 i.m. Ovarian function was evaluated twice daily by transrectal ultrasonography on Day -1, Day 0 (expected estrus), and Day 1, and once daily on Days 4, 6, 8, 10, 12, and 16 of the synchronized and return cycles. Concurrent blood samples were collected to determine plasma P4 concentrations. A one-way ANOVA was used to analyze follicle diameter variables and Fisher’s Exact test was used to analyze all other data reported (StataCorp 2007, College Station, TX, USA). There was no difference (P = 0.31) in the diameter of the dominant follicle 54 to 56 h post-Cue-Mate removal (the time FTAI would be conducted) in the CM100 (11.5 ± 1.1), CM50 (13.3 ± 1.5), CM50+G (13.7 ± 1.5), or PG (14.5 ± 0.7) groups. Synchrony of ovulation in ovulating heifers did not differ (P < 0.05) between the P4-treated groups with 12/13 (CM100), 11/12 (CM50), and 9/12 (CM50+G) heifers ovulating within 53 to 77 h after Cue-Mate removal, but was lower (P < 0.02) for the PG group (1/5). Individual heifer P4 profiles revealed that 2/15, 1/15, 3/12, and 0/5 of heifers that ovulated in the CM100, CM50, CM50+G, andPG groups, respectively, failed to re-ovulate in the return cycle. Also, 1/15, 3/15, 1/12, and 0/5 of heifers that ovulated in the CM100, CM50, CM50+G, and PG groups, respectively, developed a CL that persisted into the return cycle. This study shows the potential benefits of using intravaginal devices containing a lower amount of P4 to induce synchronized ovulation in Brahman heifers, consistent with the findings of Carvalho et al. (2008 Theriogenology 69, 167).