Zealand Agriculture Research Articles

Occupational contact dermatitis among New Zealand farmers.

Forty-six farmers were patch tested to determine whether their dermatitis was secondary to an occupational allergen. Twenty-eight had a positive patch test of which 23 were thought relevant (definite or probable). In 20 of these cases, the allergen(s) was considered to be work related (define or probable). The common allergens were pesticides (N-(1,1,2,2-tetrachloroethylthio) -4-cyclohexene-1,2-dicarboximide (captafol), ethylenebis (dithiocarbamato) manganese (maneb) and copper sulfate), rubber compounds (N-isopropyl-N-phenyl-4-phenylenediamine (IPPD) and 4-phenylene diamine base) and sunscreen chemicals.

Factors affecting choice of cash sales versus forward marketing contracts

Although the use of various forms of marketing contracts is increasing within agricultural marketing channels, there has only been a limited number of research efforts that investigate the factors influencing the structure of agricultural marketing channels and individual firms selection decisions. This article examines issues relating to why alternative forms of sales transactions may predominate in different industries and how the marketing competencies of individual firms influence the type of contract selected by a business. The results of an empirical analysis of New Zealand farmers indicates that for an individual farmer sales transaction choice is influenced by marketing competencies and strategy, farm and farm manager characteristics, and the structural characteristics of the industry in which the transaction is taking place. © 1998 John Wiley & Sons, Inc.

Commercialization and Privatization of Agricultural Extension: The New Zealand Experience

The U.S. Cooperative Extension System (USCES) faces some serious challenges. Its relevancy and necessity are under continuous scrutiny as the number of farmers and the political power of the agricultural vote diminishes. These challenges provide an excellent opportunity to explore alternative sources of funding for the USCES and methods of technology transfer to farmers. Our objectives were to review the process and results of commercialization (the transition to user-paid consultancy) and privatization (the transition from government to privately owened) of New Zealand's agricultural extension service. Full commercialization of the New Zealand extension service took nearly 9 yr (1986 to 1994) and 3 yr (1992 to 1995) of negotiating before it was sold to a private company. During the commercialization process, the market for paid advisors increased and many of them left the public extension service to become private agricultural consultants. Many farmers were initially unwilling to pay for consultancy services. On the other hand, implementation of advice and adoption of new technologies has been greater among farmers when advice and technology are purchased than when they are provided free. Since the commercialization of publicly funded extension, farmer cooperatives and commodity boards have begun to provide free or low cost services to transfer information to farmers. Educational models and goals, and client-advisor relationships have also changed as a result of user-pays. The commercialization and privatization of publicly funded agricultural extension is a relatively new process and its affect on the long-term sustainability of agriculture within a country are uncertain. Consequently, additional in-depth investigation into the process and its long-term consequences on agricultural productivity, profitability, and social well-being should be completed before initiating such a plan in the USA.

Rhizobium issues affecting the contribution of caucasian clover to New Zealand pastoral agriculture

Caucasian clover (Trifolium ambiguum) is being commercially released for use in New Zealand agriculture. Seed must be inoculated at sowing, as caucasian clover forms a nitrogen-fixing symbiosis only with specific rhizobia that are not native to New Zealand. These rhizobia have the potentially undesirable property of readily forming nodules on white clover that do not fix nitrogen. Caucasian clover inoculant strains available for use in New Zealand were found to be genetically unstable in the laboratory, and must be frequently monitored for their symbiotic properties. A strain of caucasian clover rhizobia that gives better establishment and growth of caucasian clover under oversowing conditions was identified. This strain maintained a higher level of viability under stress conditions in the laboratory and showed enhanced survival on seed in the environment. Growth of caucasian clover results in large populations of caucasian clover rhizobia in the soil. These formed nodules on white clover in the same field environment, although white clover rhizobia dominated nodule formation. Nevertheless it is possible that present caucasian clover inoculants may over time reduce nitrogen fixation and hence the production and persistence of white clover. Further research is required to develop a caucasian clover strain that does not form ineffective nodules on white clover. Keywords: caucasian clover, inoculation, nodulation, rhizobia, Trifolium ambiguum, Trifolium repens, white clover

Standardisation between livestock classes: the use and misuse of the stock unit system

The stock unit (SU) system is used extensively in New Zealand agriculture. These applications include inter- and intra-farm comparisons, rural lending and valuation, and farm system design and analysis. The livestock classes and performance levels to which SU conversion factors are applied has increased significantly since Professor Coop defined the ewe equivalent (EE) system, and now includes deer, goats and other non-conventional livestock species. This has led to a proliferation of SU values and their incorrect application and interpretation, especially in between-farm comparative analysis. Benchmarking provides a more economically rational way of improving the profitability of livestock farms than the use of standards based on SUs. Obtaining agreement on the specifications of animal-pasture-financial models to allow users to derive substitution rates between stock classes according to their farm's resources and management practice is preferred to publishing national standards for SUs. Keywords: comparative analysis, livestock classes, standardisation, stock unit

A simulation model for the spread of bovine tuberculosis within New Zealand cattle herds

Bovine tuberculosis, caused by Mycobacterium bovis, presents a major problem to New Zealand agriculture because of the risk that it poses to export-market access. New Zealand research has focused largely on the epidemiology of the disease in wildlife reservoirs, and relatively little is known about the dynamics of the disease in cattle. This study, therefore, investigates bovine tuberculosis (Tb) dynamics within cattle herds, by construction and application of a simple simulation model of disease transmission. The model was designed firstly to estimate rates of disease transmission within herds, and secondly to identify likely consequences of changes in herd Tb-testing policies. Both deterministic and stochastic versions of the model were used to achieve these aims.The model suggests that within-herd Tb transmission does occur and contributes to the reactor rates observed under annual herd testing regimens. The mass-action disease transmission coefficient (proportion of susceptible animals infected per unit time per infectious animal, i.e. not per diseased animal or per reactor), appears to be in the order of 2.7 × 10−5 per cow per day for a typical herd of around 200 animals, resulting in a contact rate (number of potentially infectious contacts made per infectious cow per day) of about 0.0073. These are average estimates for both beef and dairy herds.Model results suggest that improving the sensitivity of the test used to diagnose bovine Tb would improve control in areas where wildlife reservoirs are absent but have little effect where they are present. Reducing the time between tests of herds on Tb-induced movement control from the current 6 months to 2 or 3 months reduces the average time a herd spends on movement control and hence national Tb prevalence. In the presence of wildlife reservoirs of infection, both the total number of tests and total reactors per unit time increase, but the extent depends on the level of external infection. In all scenarios examined, involving thousands of model runs in total, infection was invariably absent from the modelled herd by the time it was considered clear of Tb based on testing results. This suggests that the caudal fold test is a realistic measure of herd Tb status and that Tb is unlikely to persist in herds under current testing practices in the absence of anergic cattle or an external source of infection. Specificity of the caudal-fold test as used in practice was estimated to be greater than 99%.

Choosing the Successor in New Zealand Family Farms

Farmers in family businesses are often interested in generational succession. Yet farming parents are often unclear about the process of choosing a successor. We undertook a grounded-method study of the succession process among New Zealand farm families. The process included five stages: watching for interest, reducing the pool of eligibles, assessing commitment, compensating the others, and placing the successor. We make suggestions for future research that will test the model of succession, and for use of these findings by farm families who are contemplating family succession.

Tractor Fatalities and Injury on New Zealand Farms

The aim of the research was to describe the epidemiology of tractor incidents on New Zealand farms which resulted in death or hospital inpatient treatment. Fatalities were identified from three independent data files for the period 1986-1991. Hospitalizations were selected from national hospital inpatient files for the period 1980-1989. There were 51 deaths, an average of 8.5 per year, or an estimated rate of 1 per 100,000 rural residents per year. Only 47% of the cases were recorded on all three databases. Those in the 60+ age group had the highest number and rates of fatal injury. There were 1,151 incidents requiring inpatient treatment, an average of 115 per year, or an estimated rate of 22 per 100,000 rural residents per year. Males in the 15 to 19 age group had the highest gender specific rate. At least 23% of the fatalities and 45% of the non-fatal injuries occurred to persons whose primary occupation was other than farming. When specific events were examined as a proportion of all events, there had been a significant decline in non fatal overturns. Our analyses also show that this was not due to other types of crash increasing over time. While overturns were an important cause of fatalities and non-fatal injury, the non-fatal injury analyses highlights the fact that the majority of tractor incidents did not appear to involve overturns. Efforts to reduce mortality and morbidity associated with tractors would be greatly facilitated by: an enhancement of national surveillance systems; in-depth studies into specific classes of events with priority being given to ?overturns?; and consideration of the elderly, children, and those whose primary occupation is not related to farming. In addition, existing and proposed legislation needs to be reviewed to ensure that it comprehensively addresses protection for all tractor users and roll over protection.

Subsoiling and surface tillage effects on soil physical properties and forage oat stand and yield

Much of New Zealand's agriculture integrates animal and crop production on poorly drained, easily compacted soils. We hypothesized that soil properties affecting forage oat ( Avena sativa, cv Awapuni) establishment on land compacted by 15 years of conventional cropping might be influenced by various subsoiling and surface tillage combinations. Plots on a Moutoa silty clay (Typic Haplaquoll) were paraplowed (P), deep subsoiled (V), shallow subsoiled (S), or were left as non-subsoiled controls (C). Subsequently, the surface 15 cm was surface-tilled (T) using a power rotary-tiller and firmed with a Cambridge roller or were not tilled (N). Oats were then sown with a cross-slot drill. Subsoiling greatly reduced soil strength. Cone indices showed disruption to 40 cm with P, 36 cm for V, and 30 cm for S. Approximately 60% of profile cone indices to a depth of 0.5 m from subsoiled treatments were less than 1.5 MPa, compared to approximately 30% for C. T slightly improved strength distribution in non-subsoiled controls but had little effect in subsoiled treatments. Subsoiling without T continued to show improved profile cone index cumulative frequency 233 days after subsoiling. Subsoiling after T in this high rainfall climate eliminated most of the separation in cumulative frequency of soil profile cone index values by two weeks after T. T reduced emergence from 142 to 113 plants per square meter and reduced yield from 5318 to 3679 kg ha −1. Forage yield increased from 3974 to 4674 kg ha −1 with subsoiling. Soil porosity, saturated and slightly unsaturated hydraulic conductivities ( K SAT and K −40) and air permeability were highly variable but generally increased with subsoiling. Oxygen diffusion rate (ODR) (using Pt microelectrodes) was also variable, but N and C treatments had consistently lower ODRs than T or subsoiled treatments. Generally, subsoiling without T produced better soil conditions and oat crop performance than the prevailing New Zealand practice of T without subsoiling.

Tractor Fatalities and Injury on New Zealand Farms

Tractor Fatalities and Injury on New Zealand Farms

Nitrogen balances and losses on intensive dairy farms

Nitrogen (N) balances were constructed for "average" dairy farms in New Zealand, south west England and The Netherlands, and for Dairying Research Corporation (DRC) farmlets varying in stocking rate and use of N fertiliser and maize grain. N surpluses were calculated to indicate the potential impact on the environment and these were compared with measured N losses from the DRC farmlets. On the average New Zealand farm, annual N inputs of 186 kg N/ha/year (mainly from N2 fixation) resulted in N outputs in milk+meat of 55 kg N/ha/year (30% efficiency) and a N surplus of 131 kg N/ha/year. Dutch farms produced 70% more milk/ha but had N inputs of 568 kg/ha, N outputs in produce of 81 kg/ha (14% efficiency) and a N surplus of 487 kg/ha. English farms were intermediate. In the DRC farmlets, applying fertiliser N at 400 kg N/ha/year increased N surpluses and nitrate leaching by 3-4 fold, resulting in nitrate-N concentrations in drainage of 2.5× the recommended maximum for drinking water. The most efficient farm system received no N fertiliser and was highly stocked (3.3 Friesian cows/ha) for very high pasture utilisation. This resulted in similar milk production/ha to Dutch farms (with 1/3 the N inputs) and a 45% efficiency of conversion of N inputs from N2 fixation into milk and meat products. Keywords: dairy farm, nitrate leaching, nitrogen balance, nitrogen fertiliser, stocking rate

Digestibility and effects of condensed tannins on digestion of sulla (Hedysarum coronarium) when fed to sheep

Abstract Sulla (Hedysarum coronarium) is a short‐lived perennial legume with an erect growth habit which is grown as a fodder crop in Mediterranean regions but is not common in New Zealand agriculture. Recent experimental work has shown potential benefits of sulla for reducing the impact and numbers of intestinal nematodes in sheep and possible benefits for wool production, so that a feeding trial was undertaken to determine its digestibility. Twelve sheep aged about 6 months were held in metabolism crates and fed sulla as a sole diet for the 20‐day experimental period. Sulla contains condensed tannins (CT) so that one group of 6 sheep were given twice‐daily oral drenches of polyethylene glycol (PEG) to bind with and deactivate the CT (PEG group) enabling a comparison with the undrenched Tannin group. The dry matter (DM) content of the sulla was 15.5%, comprising (DM basis) 33% leaf, 41% stem, and 26% flower, and all portions of the plant were eaten. The DM contained about 7.2% CT and 3.0% nitrogen (N). D...

Financial viability - a long-term view

Farm profitability is under pressure, with depressed product prices and a rising exchange rate combining to reduce farmer incomes. While exchange rate movements do affect short-term profitability, longterm trends have a much greater effect upon farm profits. While commodity prices are cyclical, over time they fail to keep up with inflation. An analysis of international commodity prices from 1949 to the present day demonstrates a reduction in real terms for all agricultural commodities. An analysis of prices received by New Zealand farmers since the 1950s shows a similar trend. The efficiency of sheep production, measured as lambing percentage and wool weights, has not demonstrated the improvements achieved by other sectors. Milkfat production per cow has doubled over the past 80 years, broiler chicken feed conversion efficiency has doubled over the past 20 years, wheat yields are two and a half times greater now than 70 years -ago, while lambing.percentage and wool weights hXVc not-significantly-improved-since-I-950.Sheep. and beef farms maintained profitability by increasing stocking rate and stock numbers per labour unit, and diversifying .into more profitable stock, such as deer. The pressures facing farmers in the mid 1990s are being faced by other farmers elsewhere in the world, and have existed since intensive farming began in New Zealand. To farm profitability today, as in the past, farmers need to continue to capitalise on technology, and modify farm outputs to match market demand, at a greater rate than?%tip~titEK -~~ - Keywords: agricultural profitability, agricultural production, commodity prices, New Zealand

Overview of Injury on New Zealand Farms

This article provides a descriptive overview of the mortality and morbidity associated with injuries on farms in New Zealand. The study utilized New Zealand’s comprehensive national injury databases. All injuries which occurred on a farm and resulted in death, hospitalization, or a compensated insurance claim were included. There were 274 injury deaths on farms between 1986 and 1991 (an average of 46 per year), 1,377 injury hospitalizations in 1989, and 15,287 compensated claims for injury in the 1989/1990 financial year. The most significant injury events on farms were incidents involving agricultural machinery (in particular tractors), motorcycle/ATV crashes, and horses. Tractors were particularly significant in terms of fatal injury while the most common events resulting in hospitalization were those involving horses and motorcycles/ATVs. The overall rate of on-farm injury per 1,000 person-years was 0.09 for fatalities (95% CI: 0.08 to 0.10), 2.7 for hospitalizations (95% CI: 2.6 to 2.9), and 28.5 for compensated insurance claims (95% CI: 28.0 to 29.1). The injury rates in males were markedly higher than those in females and the fatality rate in males increased during later life (40 years of age and over).

Expert systems for animal feeding management Part II: Farmers' attitudes

Feed management in grazing situations involves many complex decisions. Most New Zealand farmers rely on mental figuring, intuition and experience to make these decisions. Successful easy-to-use formal models are not available. This study, being Part II of a wider project, was designed to explore whether expert systems might provide useful assistance to farmers in making feed management decisions as it is clear from production figures that efficiency improvements are possible. It was also designed to explore the reasons the trial farmers held the views expressed through, largely, recording and relating them to their personal attributes. The trial farmers believed the three expert systems developed for components of the overall feed management problem were useful, and had positive economic value. It was also clear their personality, age and education level were major factors in explaining the views held.

Factors affecting white clover persistence in New Zealand pastures

Better persistence and reliability of white clover (Trifolium repens L.) is critical in achieving a more competitive New Zealand farming industry. To persist, white clover must establish well and withstand the accumulated stresses of competition from associated grasses, grazing, variable soil fertility, drought, plus pest and disease pressure. These factors vary markedly with environment and farming system, making the choice of appropriate grazing management, plant nutrition, companion species and cultivar difficult. White clover is particularly vulnerable to mismanagement and environmental stresses during spring when plant size is at its smallest. This vulnerability is further compounded by the current trend in dairying to apply high rates of nitrogen (N) which favours grass growth more than clover growth. A faster grazing rotation and/or higher stocking rates can offset the adverse effects of N on white clover by utilising the additional grass produced and reducing competition for light. Irrespective of N inputs, frequent defoliation during spring favours white clover persistence by increasing grass tiller density, resulting in better ground cover and in lower soil surface temperatures in summer. There is a threshold above which the density of associated grass suppresses clover growth. This is most prevalent in swards containing browntop, cocksfoot and kikuyu, which are more competitive against white clover than tall fescue, timothy and perennial ryegrass. Plant breeding efforts to improve persistence concentrate on increasing the rate of stolon formation and decreasing the rate of stolon death. These efforts include selecting genotypes that have better spread and persistence in association with different grasses, and genotypes that continue to grow with lower inputs of phosphate. Changes in root morphology have enhanced persistence under moderate drought stress, while significant improvements in resistance to clover cyst nematode, root-knot nematode and clover flea offer real hope in reducing the impact of these pests. Developing cultivars with higher stolon growing point densities at a particular leaf size should improve persistence while maintaining the greater yield potential. Keywords: climatic stresses, competition, diseases, grazing management, pests, plant breeding, plant nutrition, Trifolium repens L.

Diets and Reproductive Phenologies of the Introduced Ground Beetles Harpalus-Affinis and Clivina-Australasiae (Coleoptera, Carabidae) in New-Zealand

The diet and reproductive periods of Harpalus affinis (= Harpalus aeneus) and Clivina australasiae, collected by pitfall trapping from graminaceous and legume crops at four sites on the North Island of New Zealand, were determined by dissection. H. affinis was predominantly phytophagous, with a liking for weed seeds; its main animal foods were Aphididae and Diptera. Females were gravid in spring (September-November) and summer (December-February) whilst tenerals were found mainly in autumn (March-May). Diet and phenology were similar in New Zealand, Europe and North America. C. australasiae was a polyphagous carnivore, consuming 11 categories of animal food (the most frequent being Enchytraeidae and Lumbricidae) and six categories of plant food. Females contained eggs from August to March. The food and reproductive period of C. australasiae in New Zealand were similar to those previously reported for Clivina fossor in Europe and North America. Overall, both species are considered likely to play a beneficial role in New Zealand agriculture. Opportunities are identified to study further the biocontrol potential and role in ecosystem function (e.g. community assembly rules) of these species, by means of translocation experiments.

Changing International Competitiveness and Trade: Recent Experience in New Zealand Agriculture

American Journal of Agricultural EconomicsVolume 76, Issue 5 p. 1041-1046 Invited Papers Session Changing International Competitiveness and Trade: Recent Experience in New Zealand Agriculture Ron A. Sandrey, Ron A. Sandrey economist with the Ministry of Foreign Affairs and Trade Wellington, New ZealandSearch for more papers by this authorGrant M. Scobie, Grant M. Scobie professor and chairperson of the Department of Economics University of Waikato, Hamilton, New ZealandSearch for more papers by this author Ron A. Sandrey, Ron A. Sandrey economist with the Ministry of Foreign Affairs and Trade Wellington, New ZealandSearch for more papers by this authorGrant M. Scobie, Grant M. Scobie professor and chairperson of the Department of Economics University of Waikato, Hamilton, New ZealandSearch for more papers by this author First published: 01 December 1994 https://doi.org/10.2307/1243388Citations: 5AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume76, Issue5December 1994Pages 1041-1046 RelatedInformation

Liberalization in New Zealand Agriculture: Discussion

The New Zealand reforms are important well beyond their significance for New Zealand itself. This country, and no other in the industrialized world, has undertaken sweeping policy changes of the kind that economists are sometimes inclined to recommend, but are assumed to be practically unworkable or politically impossible. This has made the outcome an object of worldwide scrutiny. The proponents of such reforms-in the spirit of full disclosure I should say that I count myself as one of themhave many plausible arguments and simulation studies to back up their case. Some of the key findings are summarized by Blandford and Dewbre. But we need actual evidence. What do we find in New Zealand 1984-94?

The law of one price: a test based on prices for selected inputs in New Zealand agriculture

AbstractThe law of one price (LOOP) is an essential foundation of both the pure theory of trade and monetary theory. Strictly speaking, the law relates to prices of individual commodities. However, empirical tests of LOOP have often relied on aggregated data. In this paper, a model is derived and estimated using price data for 15 selected inputs in New Zealand agriculture. The results offer no support for the LOOP in the short run, and the results for the long run are mixed. It may be inappropriate, therefore, to assume that the LOOP holds generally in modelling exercises, particularly when models are used for policy purposes.