871 resultados para Cormorants : ecology and management
Resumo:
This book chapter represents a synthesis of the work which started in my PhD and which has been the conceptual basis for all of my research since 1993. The chapter presents a method for scientists and managers to use for selecting the type of remotely sensed data to use to meet their information needs associated with a mapping, monitoring or modelling application. The work draws on results from several of my ARC projects, CRC Rainforest and Coastal projects and theses of P.Scarth , K.Joyce and C.Roelfsema.
Disengaging leadership: Educational administration and management as a field of scientific knowledge
Resumo:
Numerous studies have shown that it is possible to manipulate follicular and luteal dynamics, thereby eliminating the need for oestrus detection in embryo transfer (ET) programmes. Fixed-time ET (FTET) protocols are based on the use of gonadotrophin-releasing hormone (GnRH) and prostaglandin (PG) F or progesterone/progestogen (P4)-releasing devices and oestradiol. The FTET protocols increases the proportion of recipients transferred, and therefore pregnancy rates, compared with the use of PGF followed by ET 7 days after oestrus. Furthermore, the addition of equine chorionic gonadotrophin (eCG) to the P4 and oestradiol-based FTET protocols results in an even higher proportion of recipients transferred, and thus higher pregnancy rates. The beneficial effect of eCG treatment may be related to increased growth of the dominant follicle and increased plasma P4 concentrations during the subsequent luteal phase. In Bos taurus x Bos indicus recipients, pregnancy rates were positively correlated with the diameter of the corpus luteum (CL) and the number of CL at ET. When repeat-breeder Holstein cows were used as recipients, FTET protocols increased number of recipients transferred and pregnancy rates compared with the traditional PGF-based synchronisation protocols. In conclusion, the use of FTET protocols eliminates the need for the detection of oestrus and results in a greater proportion of recipients transferred and satisfactory pregnancy rates. Thus, FTET optimises the use of recipients, reducing labour and animal handling and facilitating the use of ET.
Resumo:
After outlining some relevant background information about the NT crocodile farming industry and explaining the purpose of our survey of NT crocodile farmers conducted in the first half of 2005, this paper reports the results of the survey. The information received from the survey is supplemented by secondary data and by information from secondary sources. This report covers the location of respondents; the size of crocodile farms; farmers’ stated knowledge of and attitudes towards the NT Crocodile Management Plan; the involvement of farms in the harvesting of crocodile eggs and the costs involved; views of crocodile farmers about whether the NT Crocodile Management Plan encourages landholders to conserve crocodiles and their perceptions of the benefits to landholders; predicted production trends and trends in the number of farms operating in NT; economic characteristics of crocodile farms producing in NT including the economic advantages and disadvantages of crocodile farming in NT. Concluding comments provide, amongst other things, an overview of the structure of the crocodile farming industry in the NT gleaned from a consideration of data available from the NT Government’s Department of Business, Industry and Resource Development.