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The nutrition of grazing ruminants can be optimized by allocating pasture according to its nutritive characteristics, provided that nutritive concentrations are determined in near-real time. Current proximal spectrometers can provide accurate predictive results but are bulky and expensive. This study compared an industry standard, 'control', proximal spectrometer, often used for scientific estimation of pasture nutrient concentrations in situ (350–2500 nm spectral range), with three lower-cost, 'next-generation', handheld spectrometers. The candidate sensors included a hyperspectral camera (397–1004 nm), and two handheld spectrometers (908–1676 nm and 1345–2555 nm respectively). Pasture samples (n = 145) collected from two paddocks on a working Australian dairy farm, over three timepoints, were scanned in situ by each instrument and then analysed for eight nutritive parameters. Chemometric models were then developed for each nutrient using data from each sensor (split into 80:20 calibration and validation sets). According to Lin's Concordance Correlation Coefficient (LCCC) from independent validation (n = 29), the hyperspectral camera was the best candidate instrument (LCCC from 0.31 to 0.85, and 0.67 on average), rivalling the control sensor (LCCC from 0.41 to 0.84, and 0.67 on average). Consideration was given to whether the hyperspectral camera's success was due to spectral range or data type/capture method. It was found that the 400–920 nm (trimmed) spectral region was slightly less sensitive in principle to nutrient concentrations than higher spectral ranges. Therefore, the predictive performance of the camera was attributed to the advantage of gathering data as hyperspectral images as opposed to single spectra. [ABSTRACT FROM AUTHOR]

The majority of dairy farmers and processors in Australia and New Zealand are considered world class due to their ability to produce dairy products at a cost that is competitive on the world market without requirement for subsidy. International and domestic forces beyond the farm influence the international competitiveness of Antipodean dairy systems, as much or more than, the within-farm characteristics of the systems. Critical external forces include: world population growth, protein demand from increasingly wealthy developing countries, dairy supply from domestic and international producers, international dairy prices and exchange rate volatility. Within farm, the keys to persistent profitability, business survival, and growth will continue to be management ability and labour skill as well as the relationship between milksolids (milk fat + milk protein) produced per system and total production costs. Domestic forces will include competition for resources such as land, water, quality labour and capital, and public expectation that farms will meet the costs of community environmental and welfare objectives. Public and industry investment in research, development and extension in innovations that increase productivity is essential if dairying is to remain competitive. The operation of the comparative advantage principle determines which industries thrive, or decline, in an economy. New Zealand dairying has a strong comparative advantage over alternative pastoral industries which will continue. In Australia, the comparative advantage of dairy farming over alternative activities is less clear-cut. History shows that the best farmers and processors handle risks such as market and climate volatility and other challenges better than others, and their prospects are positive. However, world class performers in the future dairy industry will certainly not be all, or even the majority, of the current population of dairy farmers. Australian and New Zealand dairy farm businesses are world class, but there is no guarantee that their comparative advantage over alternative land uses will continue. An analysis of key physical and financial characteristics of dairy farming shows that there is wide variation in financial performance for farm businesses no matter what level of feed inputs are used. The best performers in both countries are poised to take advantage of the increased global demand for milk products. [ABSTRACT FROM AUTHOR]

For Australian and New Zealand dairy farms, the primary source of home-grown feed comes from grazed perennial pastures. The high utilisation of perennial pasture is a key factor in the low cost of production of Australian and New Zealand dairy systems and, hence, in their ability to maintain international competiveness. The major pasture species used are perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.), normally grown in a simple binary mixture. As pasture production has been further driven by increasing use of nitrogen fertiliser and irrigation, farms are getting closer to their economic optimum level of pasture utilisation. Increasing inputs and intensification have also increased scrutiny on the environmental footprint of dairy production. Increasing the diversity of pasture species within dairy swards presents opportunities to further increase pasture utilisation through additional forage production, extending the growing season, improving forage nutritive characteristics and, ultimately, increasing milk production per cow and/or per hectare. Diverse pastures also present an opportunity to mitigate some of the environmental consequences associated with intensive pasture-based dairy systems. A consistent finding of experiments investigating diverse pastures is that their benefits are due to the attributes of the additional species, rather than increasing the number of species per se. Therefore, the species that are best suited for inclusion into dairy pastures will be situation specific. Furthermore, the presence of additional species will generally require modification to the management of dairy pastures, particularly around nitrogen fertiliser and grazing, to ensure that the additional species remain productive and persistent. Diverse pastures offer benefits to pasture-based dairy systems in terms of increased forage and animal production, improved resilience and the potential to reduce nitrate leaching. The management required to maintain the diversity in the pastures may limit their application. However, the benefits of diverse pastures can be archived with only three species making their management and application simpler. [ABSTRACT FROM AUTHOR]