The value of decision support models for farmer learning

Advances in computer technologies and mathematical modelling have enabled technology providers to develop decision support tools. Studies with farmer groups showed that the value of these tools to farmers may be as much for learning as for decision support. Stockpol was used in one farmer group to support decisions around farm systems design. Quickfeed was developed with another group that were interested in pasture quality, and Bestbreed with a group whose target was lamb growth rate from birth to weaning. The ultimate aim in all three studies was to improve farm profitability. When evaluating the studies, farmers ranked the overall study as being highly effective (72 to 86 %) in achieving the goal of improved profitability yet the value of the models was ranked much lower (40 to 44%). This result may be explained by the perception value relates to hands on use, rather than the learning associated with using the model and interaction with the information encapsulated in the model. Here the learning environment included collecting information to use in the model and comparing the model output with the actual changes that had occurred on farms. In other words, farmers were learning through participation. The value to farmers of computer models or tools may be better measured by their success in improving farm profitability. In these studies, this lay directly in what the farmers learnt and how their behaviour changed as a result of participation in the overall study rather than in continued use of the models per se. This paper discusses this aspect of farmer learning and the benefits of packaging technology in the form of decision support tools. Keywords: computer technologies, decision support, farmer study groups, learning, mathematical modelling, technology providers</jats:p

Improving the balance of sheep and beef cattle livestock systems

Two data sets were used to analyse the impact of changes in stock policy from a dominant breeding ewe system to a dominant beef cattle finishing system. These included data from a farmlet trial and data from a monitored study farm. The Stockpol model was used to carry out the analyses. Required daily pasture demand and average minimum pasture covers increased as cattle finishing increased. Stock numbers had to be reduced for the policies to become biologically feasible, that is, for the increased pasture demands and pasture covers to be attainable on the farm. Historic stocking rate was not a good guide to the reduced stocking rate required. Tests of biological feasibility should be carried out before a change in policy can be analysed for its financial merits. Keywords: biological feasibility, finishing, pasture cover, pasture demand, stock policy, systems</jats:p

THE USE OF PASTURE HEIGHT AS A PREDICTOR OF FEED LEVEL IN NORTH ISLAND HILL COUNTRY

Considerable effort is expended measuring pasture parameters that relate to animal perform mance. Traditionally farmers have used visual impact and experience as their method of pasture assessment to make management decisions. The simplest measurement collected by researchers, pasture height, is developed to the point where it can be used as a guide to predict pasture mass and animal performance. This paper presents relationships between height and mass for improved pastures in summer dry North Island hill country. A pasture 5cm tall will give hogget growth of 60 gjday in summer, 90 in autumn, 100 in winter and 200 in spring. Similarly 5cm will be 2250 kg DM/ha in summer, 1900 in autumn, 1520 in winter, 1640 in spring and 2200 in late spring. Keywords: Height, mass, predictor, grazing, quality, animal performance, feed levels, parameters, pasture.</jats:p

Group monitoring, a basis for decision making and technology transfer on sheep and beef farms

Group farm monitoring is a team approach to technology transfer involving farmers, consultants and researchers. Biological and financial components of farm production are monitored to provide data for decision making and a knowledge of the farm which is shared among the group.Scientists from the Whatawhata Research Centre (WRC) provide comparative information and relevant technology. Production gains on the monitor farms have been achieved within 3 years and further gains are possible. Group farmers benefit from renewed enthusiasm in farming and an increased interest in new technology. Key success factors are group ownership of decisions and outcomes and the credibility of consultants and scientists who are seen to stand by the technology delivered. MAF Technology consultants initiated farm monitoring in the Northland area and have benefited as have farmers through the WRC contact, which provides a broad spectrum of information from a multi-disciplined research group. Based on the Northland success, group farm monitoring has been accepted as a model for technology transfer throughout New Zealand. Keywords group farm monitoring, information, decision making, technology transfer</jats:p

The impacts of change in forage quality and seasonality on sheep farm profitability

benefits of altering the quality and seasonality of pasture supply in sheep farming enterprises. Three representative regions in New Zealand were studied; winter-cold and summer-wet (e.g., Southland, Otago and Central North Island); winter-cold, summer-dry (e.g., South Island East Coast); and winter-warm, summer-dry (e.g., North Island East Coast). Two different lamb-finishing enterprises were also analysed within each region; a conventional system where the lamb supply pattern was aligned with feed availability, and a supply contract system where more lambs were supplied for processing outside the normal season. Improving the seasonality of feed supply increased gross margins by $26 to$126 per hectare depending on the region. The greatest gains from improved seasonality occurred in the winter-cold scenarios. Improving forage quality had a more positive impact than improved seasonality changes with gross margins increasing by $53 to$148 per hectare depending on region. Overall the impact of the forage supply and forage quality changes was similar for the two lamb-finishing systems. Keywords: lamb-finishing, pasture production, pasture quality, systems analysis</jats:p

Variation in cattle liveweights at marketing

The liveweights of Friesian bulls farmed on 3 farmlets during 4 years were analysed to find how the variation in liveweight increased through time, and to review some possible farm management strategies for limiting the increase in this variation. There were 59 bulls in 1986, 66 bulls in 1987, 59 bulls in 1988 and 61 bulls in 1989. The variation in animal liveweights within a mob increased linearly through time. The small variance in the slopes of the estimates indicated that the increase in liveweight variation through time could be predicted very accurately. The rate of increase of variation through time differed in only one year (1987; P&lt; 0.01). Variation in animal liveweight between farmlets was constant through time, and not associated with the rate of increase of within mob liveweight variation. It was shown that the ranking of animals within the frequency distribution of animal liveweight changed through time. Thus the current liveweight rank of an animal was no guide to liveweight rank 5 or 6 months in the future. This suggests that minimising the increase in liveweight variation through time by dividing a mob of cattle is not feasible. The importance of control of variation in agricultural products for the operation of on-farm quality assurance schemes is discussed, and avenues for exploration of management tactics designed to minimise variation in the production of animals for slaughter suggested. Keywords: bulls, liveweight, marketing, on-farm - quality assurance</jats:p

Performance of new pasture cultivars in a hill country finishing system

On 6 of a set of 12 self-contained experimental farmlets, improved pasture cultivars 'Ellett' ryegrass, 'Grasslands Wana' cocksfoot, 'Grasslands Tahora' white clover, Whatawhata Early Flowering' white clover, 'Mount Barker' sub clover, 'Tallarook sub clover, 'Grasslands Mama prairie grass, 'Grasslands Pitau white clover and 'Grasslands Pawera' red clover were successfully established in 1986. Measurements began May 1987. Results presented to May 1989 include pasture production, animal production and financial returns. Matua prairie grass failed to persist beyond spring 1988 but clovers including Pawera and Pitau in these pastures increased summer production in 1989. In summer 1989 the improved steep pastures produced 8 kg DM/ha/day more feed than the resident pastures, with most of this increase owing to Wana cocksfoot. Lamb numbers and lamb weight gains were greater with improved pastures. Bulls were priority finishing animals and their weights were insensitive to pasture treatment. Current returns from this experiment show little to justify the investment made in introducing new cultivars into existing developed hill pastures. Keywords pasture cultivars, hill country, finishing systems, pasture improvement</jats:p