Advances in pasture management for animal productivity and health

Abstract

A wide range of management techniques is available to enhance quantity and quality of forage supply to grazing animals throughout the annual production cycle. Within broad limits, dry matter (DM) production is relatively insensitive to management of defoliation frequency, severity and duration. However defoliation management has effects on feed quality which can be enhanced, in particular, by control of pasture growth in the spring through maintenance of relatively low average pasture masses. Treading damage can have significant immediate and ongoing effects on pasture production and farmers can use a range of management techniques to minimise these. Fertiliser application practices have a potent influence on pasture production and seasonality of that production. Available soil nitrogen is the primary nutrient deficiency limiting production in New Zealand's characteristically grass-dominant pastures. Nitrogen fertiliser usage has increased markedly in recent years, particularly to grow substantially greater amounts of forage during the cool season, and this trend looks set to continue. However, the use of nitrogen fertiliser has important environmental implications. Pasture renewal and forage crop use has also increased in recent years. Care needs to be taken in conducting cost-benefit analyses, selecting the options that best meet the needs, and in establishment and subsequent management practices. Ryegrass (perennial and hybrids) and white clover remain the primary choice for permanent pasture renewal, the availability of safe endophytes having largely alleviated effects of endophyte toxicosis. Special-purpose mixtures are used, especially in dry environments. Italian ryegrasses, brassicas and chicory are common choices for forage crops. A range of management techniques can be used to alleviate deleterious effects of some forages, including ryegrass endophyte toxicosis, facial eczema, and toxins associated with Fusarium fungi. Generally these techniques are not totally effective. More research is required to increase our understanding of these disorders, and in order to develop more effective and reliable management practices.

Sheep Rumen Fermentation Characteristics Affected by Feeding Frequency and Feeding Level When Fed Fresh Forage

“…Feeding frequency affects many aspects of ruminants, including rumen fermentation function [4], dry matter voluntary intake and feed digestion [5], feces and urine excretion [6], and animal performance [7,8] and behavior [9]. Herbs, such as chicory, are increasingly used as alternative forage species for dairy and meat production either in their monocultures or mixtures with legumes [10,11]. Previous feeding experiments evaluating these novel forage species were mostly conducted under a two meals a day feeding regime with feeding levels around maintenance metabolizable energy (ME) requirements [12,13].…”

Fertiliser Nitrogen and Factors Affecting Pasture Responses

“…Biological N fixation rates range between 100-300 kg ha -1 yr -1 for grass/clover pastures in New Zealand (NZ) [1]. Although N can be provided from these sources, insufficient soil N in NZ grass-dominant pastures is the primary limiting factor of production [2] and pasture responses to N fertiliser are still very sensitive.…”

“…Fertilisation of pasture with phosphorus (P), sulphur (S) and other nutrients to stimulate symbiotic N fixation for N supply has been considered to be more cost-effective than direct application of N fertiliser [2]. N fertiliser application was suggested only after legume production was maximised under a high soil fertility status in terms of P, potassium (K), S, lime and trace elements [11].…”

Sustainable Pasture Management

“…It is important to consider the efect of grazing management on pasture growth, tiller density, pasture quantity and quality and soil properties. Many factors afect quantity and quality of pastures like farm topography, weather variation among the seasons, botanical composition, herbage cover, stocking rate, seasonal grazing, antiquality compounds in grasses and application of diferent practices [23,24].…”