Search

Underwater cameras were used to observe the breeding behaviour of the endangered eastern freshwater cod, Maccullochella ikei, over 3 years and across three areas in the Mann and Nymboida rivers, Australia. The annual breeding season for M. ikei was short and succinct, lasting only 8–10 weeks. Spawning commenced each year in the lowest altitude area during the first week of spring, and approximately 1 week later in the closest upstream area. Day-length is the primary spawning cue for M. ikei, but increasing water temperature may also be of importance. Nesting sites were located in slow-flowing pools, under cover such as large boulders and bedrock shelves, at depths of 0.9–4.0 m, and with one or two entrances only. The nesting site was vigorously cleaned by the male up to 1 week prior to spawning and was only entered by the female for spawning. Paternal care of eggs and larvae was undertaken for up to 24 days, after which larvae dispersed. Greater protection of breeding M. ikei must be a management priority to ensure long-term conservation of the species. [ABSTRACT FROM AUTHOR]

Focuses on a study which attempted to dissolve insoluble organic matter (IOM) from a bacterium and a Recent lacustrine sediment, in an ionic liquid. Information on the extensive characterization of organic matter; Materials and methods used in the study; Results.

1. The possibilities of pasture evaluation in terms of milk production have been examined, experimentally, using invidually grazed cows on a ryegrass-clover ley. 2. A significant linear relationship between mean milk-yields and estimated dry-matter intakes over a three-week period was obtained. 3. Under the conditions of this experiment it was found that the relationship between milk yields and estimated fresh-herbage intakes was also linear, the correlation coefficient being as high as that between milk yields and dry- matter intakes. 4. An intake-output equation was calculated in the form: y = 0.2900x1 + 0.0117x2 + 2.1139x3 where y = dry-matter intake, x1 = fat-corrected milk yield, x3 = live-weight gain, all in lb. per day, and x2 = live weight in lb. 5. The precision of estimates of dry-matter intake using sample herbage cuts and dry-matter determinations has been examined. 6. The numbers of cows required in comparative experiments with two treatments to give a 95% chance of detecting given differences between mean yields of milk and fat-corrected milk have been estimated. [ABSTRACT FROM AUTHOR]

The effect of adding glycollic or formic acids, molasses and barley meal, and of the wilting of the herbage on the quality, composition and nutrient losses of silage made from lucerne is discussed. The acid and barley-meal additions gave the best silages, but with the latter treatment, the chopping of the lucerne probably had a considerable effect on the silage produced. Wilting the lucerne gave a well preserved silage, but overheating occurred in the mass affecting the digestibility of the crude-protein and the carotene contents. The molassed silages were inferior to the others in quality. [ABSTRACT FROM AUTHOR]