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During the past 20 years, there has been a contraction in the New Zealand Thoroughbred industry and, to a lesser extent, within the Standardbred industry. These changes have seen an increasing proportion of the market being associated with fewer larger commercial farms. Many of these farms manage their own mares, and the mares and foals of several clients. This, in turn, has increased the similarity of the management of breeding and young stock within New Zealand. The temperate climate allows the majority of the management of breeding and young stock to be pasture based. The predominant pasture is ryegrass-clover mix that has been demonstrated to provide adequate nutrition for growth and development. The temperate climate also permits management of horses at pasture year round, which is proposed to stimulate development of the musculoskeletal system. Apart from a brief period during weaning, most young stock remain at pasture from birth until the start of yearling preparation. Free access to pasture exercise provides the opportunity to stimulate the musculoskeletal system for the future challenges as a racehorse. The export focus of many of the equine industries heavily influences the management decisions. Despite the availability of good-quality pasture post-weaning, many foals receive up to 50% of the daily dietary energy requirement as concentrates, possibly reflecting the emphasis on early sales as yearlings and the drive to optimise growth. The observations of drench resistance of common internal parasites presents an emerging problem for pasture-based production systems. Alarge proportion of the Thoroughbred foal crop is exported as yearlings or ready to run 2-year-olds. There is an increasing trend for Standardbreds to be sold as yearlings and this has resulted in changes in the management of Standardbred young stock. [ABSTRACT FROM AUTHOR]

The aim of the present research was to compare milk fatty acid composition of cows grazing perennial ryegrass–white clover pasture (RGWC), with that of cows grazing alternative forages of chicory or plantain. Fifty-four cows, balanced for milk solids, days in milk and bodyweight, were divided evenly into replicated groups of six cows/group. Cows grazing chicory or plantain had similar estimated dry-matter intake (17.7 kg DM/cow.day) and milk-solid (MS) yield (1.93 kg MS/cow.day), which were greater (P < 0.05) than for cows grazing RGWC (15.6 kg DM/cow.day and 1.65 kg MS/cow.day). Milk produced from cows grazing chicory or plantain contained greater proportions of omega-3 fatty acids (FA) than that from cows on RGWC (P < 0.01), despite lower omega-3 FA in herbage. RGWC increased the percentage of conjugated linoleic and vaccenic acids in milk compared with those of milk produced from herbs (P < 0.01). This reflects the greater percentage of α-linolenic acid in RGWC (P ≤ 0.02) than in forage herbs. The changes in FA profile from the herbage to the milk suggests less biohydrogenation in cows grazing the herbs. Forage herbs demonstrated the potential benefit to alter milk FA composition, while increasing milk production. Milk fatty acid profile has implications on human health, processing quality and storage characteristics of milk products. This research compared milk fatty acid composition of cows grazing perennial ryegrass–white clover pasture with that of cows grazing herbs chicory or plantain. Forage herbs demonstrated the potential benefit to alter milk fatty acid composition, while increasing milk production. [ABSTRACT FROM AUTHOR]

The canopy structure of grasslands is a major determinant of their use-value, as it affects the quantity and quality of the forage removed when mowed or grazed. The structure of this canopy is determined by individual plant architecture, which is highly sensitive to both environmental variations and management practices such as cutting regimes. In the case of perennial ryegrass (Lolium perenneL.), this architectural plasticity may partially be mediated by a self-regulation process, i.e. the actual state of the architecture (e.g. length of the pseudostem) may indirectly control some morphogenetic processes. To test the robustness of this hypothesis, we designed an exploratory model of ryegrass morphogenesis exhibiting this cybernetic behaviour. This functional-structural model is based on the L-system formalism. It was able to capture satisfactorily the major quantitative architectural traits of ryegrass under non-limiting growing conditions and under a cutting constraint. From these simulation results it appears that (i) self-regulation rules could be of practical use to ryegrass modelling, and (ii) when activated in an integrated model, they are not markedly incompatible with observations. [ABSTRACT FROM AUTHOR]