Short-term food deprivation does not improve the efficacy of a fish oil finishing strategy in Murray cod

Two groups of fish (Maccullochella peelii peelii) were fed for a 90-day conditioning period on a canola oil diet (CO) or a fish oil diet (FO). Canola oil diet fed fish were then shifted to the FO diet for a 90-day finishing period. A variable period of  starvation (0, 5, 10 and 15 days) was introduced to reduce the initial lipid level of CO fed fish at the beginning of the finishing period and therefore accelerate the rate of recovery of FO-like fatty acids. During starvation, fish did not show  significant reduction in total lipid content, either in the fillet or whole body. At the end of the conditioning period, fatty acid composition of the diet was mirrored in fish tissues. These differences came close to levelling out following re-feeding, with the exception of n - 6 polyunsaturated fatty acids (PUFA). However, no  effects of the starvation periods on the final fatty acid make-up of fish were recorded. The results of this trial show that Murray cod, when subjected to a starvation period of up to 15 days, does not lose an appreciable quantity of lipid and, therefore, the tested starvation approach to reduce the initial level of lipid has to be considered unsuccessful. 

Revised stratigraphy of the Blanchetown Clay, Murray Basin: age constraints on the evolution of paleo Lake Bungunnia

Paleo Lake Bungunnia covered more than 40 000 km2 of southern Australia during the Plio-Pleistocene, although the age and origin of the lake remain controversial. The Blanchetown Clay is the main depositional unit and outcrop at Nampoo Station in far-western New South Wales provides the most continuous lacustrine section preserved in the basin. Here the Blanchetown Clay represents the maximum lake fill and comprises: (i) a basal well-sorted sand with interbedded clay (Chowilla Sand), representing initial flooding at the time of lake formation; (ii) a thick sequence of green-grey clay comprised dominantly of kaolinite and illite, with the apparently cyclic occurrence of illite interpreted to represent cool and dry glacial climatic intervals; and (iii) a 2.6 m-thick sequence of finely laminated silt and silty clay, here defined as the Nampoo Member of the Blanchetown Clay. New magnetostratigraphic data constrain the age of the oldest lake sediments to be younger than 2.581 Ma (Matuyama-Gauss boundary) and probably as young as 2.4 Ma. This age is significantly younger than the age of 3.2 Ma previously suggested for lake formation. The youngest Blanchetown Clay is older than 0.781 Ma (Brunhes-Matuyama boundary) and probably as old as 1.2 Ma. The Nampoo Station section provides a framework for the construction of a regional Plio-Pleistocene stratigraphy in the Murray Basin.

Sub-surface geology of the Kerang District, Murray Basin, Southeast Australia

The subsurface geology of the Kerang District was examined. The stratigraphic relationships between the Cenozoic western marine and eastern non-marine provinces of the Riverine Plain of the Murray Basin are now far better understood. A new three-fold subdivision of the Renmark Group, including the new Mystic Park Formation, is proposed.

Living with Dungalah (Murray River) : the case study of an environmental issue in Australia

This research is a case study of Dungalah, a river Europeans call the Murray which describes and accounts for the past, present and future experiences of Indigenous and non-Indigenous communities in their protection, use and management of the Dungalah and its surrounding land. It provides a snapshot of the experiences of the researcher, her family, friencds and the Yorta Yorta people, living with Dungalah.

Murray and Marx

Theory from Marx and related thinkers challenges interpretation of Les Murray's poetry. Topics discussed are: dialectics and dreams; death and its place in our lives; and poetry and religion. Using Marx, religious ideas are given meaning for our lives and thus, it is argued, interest and complexity is discovered in Murray's poetry.

Impacts of fish oil replacement in Murray cod nutrition

Fish oil use in aquacultural feeds is an unsustainable practice. This study investigated the efficacy of vegetable oil inclusion on the growth, fatty acid composition and lipid metabolism of Murray cod. Results indicate that fish oil can be substituted only partially without compromising fish growth and final quality.

Biology and management of Murray cod reproduction within controlled environments

The emerging Murray cod aquaculture industry is currently restricted by a lack of consistent and year-round production of fingerlings. Biological information and reproductive technologies developed during this research have facilitated the development of indoor, environmentally-controlled breeding practices for this species, thereby enabling Murray cod juveniles to be produced on-demand.

Nutritional and organoleptic quality in intensively farmed Murray cod

This research aimed to determine the nutritional and organoleptic changes associated with different purging procedures in farmed Murray cod. Murray cod, a highly valuable species from a nutritional point of view, greatly benefits from a period of purging in clean water before being consumed.

Haematology of cultured Murray cod

Murray cod are Australia's largest freshwater fish: endangered in the wild, but supporting a boutique industry. This project studied the blood cells of Murray cod and those affected by the disfiguring chronic erosive dermatopathy. This has provided insight into the factors affecting Murray cod health.

Macro and micro nutrient requirements of the young of Australian native freshwater fish : silver perch, Bidyanus bidyanus and Murray cod, Maccullochella peelii peelii

Studies the nutritional requirements and growth of two Australian native freshwater fish. Examines the dietary protein, and lipid requirements of silver perch and Murray cod, and the dietary requirement for essential amino acids and fatty acids of silver perch. Considered the first nutrition study of these species based on feeding trials, dose-response experiments and purified diets.

Importance of riparian vegetation to terrestrial avifauna along the Murray River, south-eastern Australia

Bird life occurring along the Murray River was distinctly different from surrounding much drier vegetation. It was found that the presence of the Murray River, with it's associated moist Red Gum forests, provide a corridor whereby birds typically of cool climates can expand their range and occur in an arid landscape.

Chronic ulcerative dermatopathy syndrome in Murray cod

Chronic ulcerative dermatopathy is a disease affecting Murray cod in aquaculture facilities that utilise groundwater. This study investigated the effects of this condition on key physiological processes and developed a cost-effective method of pre-treating the groundwater source that prevents the condition arising in Murray cod.