Perennial ryegrass/white clover swards have some limitations in temperate grazed dairying systems. This study tested the hypothesis that farmlets based on alternative species would be equally or more profitable than those perennial ryegrass-based, and would produce more herbage in summer-dry conditions. Six farmlets were established; three with perennial ryegrass- and three with tall fescue-based swards. For each grass species, one farmlet was solely based on grass-clover swards while the other two had either chicory-red clover or lucerne crops planted on 20%-25% of the area. Animal- and herbage performance-related variables were measured for 3 years, and calculated financial performance was evaluated. Using tall fescue improved total annual herbage yield compared with perennial ryegrass, but animal production and operating profit were lower. This was likely due to the reduced yield and nutritive value of tall fescue during spring and an associated decline in daily milksolids production. The deficit in spring milksolids production was never recovered, despite greater herbage production from tall fescue during summer/autumn. Incorporating chicory-red clover or lucerne crops reduced both annual herbage and milksolids production. This reduced farm income, while increasing operating expenses as the farmlets required crop renewal and more purchased supplementary feed to maintain feed supply. Under the conditions of this study (i.e., partial irrigation, high nitrogen supply), changing the forage base from perennial ryegrass to tall fescue did not improve animal production or profitability, nor did incorporation of crops on 20%-25% of the farmlet area.

Two DairyNZ farmlets, differing in nitrogen fertiliser inputs, cow genetic merit and autumn/winter grazing management, with stocking rates of 2.6 ('Future') and 3.2 ('Current') cows/ha, were compared for pasture residual and quality over 4 years. Target intakes for lactating cows were 18 and 16 kg DM/cow/day, respectively, with target grazing residuals of 3.5-4 cm (1500 kg DM/ha in late winter/spring, 7-8 clicks on the rising plate meter) for both herds. Measurement of grazing residuals, pasture quality and botanical composition identified small differences between farmlets. Grazing residuals on the Future farmlet averaged 0.2 cm (0.4 clicks on rising plate meter, RPM) (P

This study investigated the immediate and long-term effects of temporary alterations to postpartum milking frequency (MF) on milk production, body condition score (BCS), and indicators of energy status in pasture-grazed cows supplemented with concentrates. Multiparous Holstein-Friesian cows (n=150) were randomly assigned to 1 of 5 groups at calving: milked twice daily (2×) throughout lactation (control), or milked either once daily (1×) or 3 times daily (3×) for 3 or 6wk immediately postpartum, and then 2× for the remainder of lactation. During wk 1 to 3 postpartum, cows milked 1× produced 15% less milk and 17% less energy-corrected milk (ECM) than cows milked 2×. This immediate production loss increased to 20% less milk and 22% less ECM during wk 4 to 6 postpartum for cows that remained on 1× milking; these animals also produced less than 1× cows switched to 2× milking after 3wk. During wk 8 to 32, when all cows were milked 2×, those previously milked 1× had sustained reductions in milk (−6%) and ECM (−8%) yields, which were not affected by the duration of reduced postpartum MF. In contrast, cows milked 3× postpartum had 7% greater milk yields during wk 1 to 6 compared with 2× controls, irrespective of the duration of increased MF. Milk yields also remained numerically greater (+5%) during wk 8 to 32 in cows previously milked 3×. Nevertheless, yields of ECM were not increased by 3× milking, because of lower milk fat and protein contents that persisted for the rest of lactation. In addition, indicators of cow energy status reflected an increasing state of negative energy balance with increasing MF. Cows milked 1× postpartum had greater plasma glucose and lower plasma nonesterified fatty acid concentrations during the reduced MF, and plasma glucose remained lower for 2wk after cows had switched to 2× milking. Moreover, BCS was improved relative to 2× controls from wk 5 to 6. In contrast, cows milked 3× had lower plasma glucose concentrations, greater plasma nonesterified fatty acid concentrations, and greater BCS loss during wk 1 to 3; however, greater body fat mobilization was not sustained, indicating that additional energy supplements may be required to achieve better milk production responses. In conclusion, temporary 1× milking had lactation-long negative effects on milk and milk component yields but improved cow energy status and BCS, whereas temporary 3× milking immediately increased milk yield but did not improve milk fat and protein yields in pasture-grazed cows.

Pressure on New Zealand's largely pasture-based dairy industry has grown with a drive to increase production, expansion into new regions and demand for farmers to mitigate environmental impacts e.g., leaching of excess urinary nitrogen. A 3-year trial in the Waikato investigating the use of mixed pasture (e.g. perennial ryegrass, white clover, prairie grass, lucerne, chicory and plantain) showed similar annual dry matter (DM) production to standard pasture (perennial ryegrass and white clover) with greater yields of mixed pasture during summer (December, January, February) when lucerne and chicory grew better than perennial ryegrass in the warm, dry conditions. However, this yield advantage did not persist during the winter (June, July, August). Milk yields from cows grazing the mixed and standard pasture were similar. The mixed pasture retained a high level of species diversity and, while a single "magic bullet" is an unlikely solution to the challenges facing dairy farmers, increased species diversity could reduce risks and increase pasture stability.

Two experimental farmlets were established in the 2001/02 season and run continuously to 2010/11, comparing the impact of two nitrogen (N) fertiliser systems on milksolids (MS) production, profitability and the yield and composition of ryegrass-white clover pastures. Treatments were: 1) No-N. No N fertiliser applied, stocking rate 2.56 cow equivalents/ha (including replacements); 2) Control. Average of 181 kg N/ha/year applied as urea, stocking rate 3.06 cows/ha (replacements grazed off farm). Annual pasture production was, on average, 2.9 t DM/ha greater on the Control farmlet compared with the No-N farmlet (P<0.001). Annual MS/ha was 193 kg/ha greater (P<0.01) on the Control farmlet. Despite a reduction of 1.07 kg MS for every kg N not applied, profitability was very similar for both farmlets in 6 of the 9 years. Compared with No-N, the profitability of the Control farmlet improved as milk price increased above $5.10/kg MS. While the farmlets confirmed that profitable milk production systems can be achieved without N fertiliser applications on well-established Waikato dairy pastures, N fertiliser is useful for increasing profitability and milk production, particularly when the ratio between milk price and the cost of fertiliser is favourable.

The herbs chicory ( C ichorium intybus L.) and plantain ( P lantago lanceolata L.) are increasingly popular summer forage cropping options for dairy producers. However, the impact of different establishment methods on their productivity is largely unknown. Four establishment methods for chicory and plantain crops sown into non-cultivated ryegrass pastures in spring were compared. Establishment methods included direct-drilling or broadcasting seed into existing pastures, with or without herbicide application before sowing in a 2x2 factorial design. It was hypothesized that plant establishment and growth would be enhanced by spraying to kill existing ryegrass pasture and direct-drilling herbs (Spray and Drill, SD) compared with broadcasting seed with no herbicide application (Unsprayed and Broadcast, UB). This hypothesis was supported with an additional 2 center dot 12 center dot 3tDMha1 grown over 201d from swards established by SD, compared with swards established by UB. The SD method also increased the plant density of the herbs and reduced the proportion of weed species. Spraying and direct drilling is more expensive than broadcasting seed with no herbicide application, but the increase in yield means that extra feed can be supplied at less than half the cost of purchasing the equivalent amount of feed. Therefore, for optimal economic outcomes, chicory and plantain swards should be established by applying herbicide to existing pasture and direct-drilling seed.

The DairyNZ Modelling Group has developed a model called the Conservation Demo to assist in identifying and conserving surplus pasture on dairy farms. The hypothesis was that a computer algorithm would be able to make decisions concerning timing and amount of conservation similar to an experienced pasture manager. Weekly grazing decisions on DairyNZ farmlets, with stocking rates of 2.6 to 3.5 cows/ ha, were made by a team of research staff over three years. The model was run for each farmlet to compare its recommendations with the conservation decisions made by the research team. In spring on all farmlets and in summer on the higher stocked farmlets, the model was more conservative than the team in recommending paddocks to be closed in all seasons. In summer 2011/12 the recommendations from the model were more variable week-to-week (paddocks being closed one week and not the next), and on the lower stocked farmlet the model was more aggressive than the team. The Conservation Demo is a useful tool for identifying surplus pasture if the output is moderated by the farm manager, and the use of a feed wedge in conjunction with the model would improve the decisions. However the model requires pasture covers for each paddock, ideally at least weekly, and currently

Grazed forage underpins the productivity and economic performance of new Zealand's pastoral industries. This trial aimed to increase grazeable forage grown by 50% from 17 to 25 t DM/ha to meet industry targets.

The effects of legume forages on whole farm productivity and profitability (Economic Farm Surplus, EFS) were assessed for the 2006/2007 and 2007/2008 milking years in a dairy farmlet systems trial. Keywords: dairying, Economic Farm Surplus, legumes, lotus, lucerne, milksolids, perennial ryegrass, red clover, white clover

Land application of farm dairy effluent (FDE) is preferred over pond treatment because of the potential reduction in environmental impacts, and recycling of valuable nutrients. Recent findings from the past 5 years of research by AgResearch and Dexcel are presented to provide an overview of the effects of applying FDE to pastures. Results indicate that significant pasture responses to applying FDE at increasing rates of N were found in both the mowing and grazing trials. There was no difference in pasture responses between FDE and urea when applied at the same rate of N. The ryegrass content of pastures increased with increasing N rates whether from effluent or urea. N and nitrate-N concentrations in the herbage showed some increases but were not excessive at rates up to 400 kgN/ha/yr. Pasture concentrations of other nutrients (except K) were unaffected by the rate or form of nitrogen applied. Both pasture K and soil K levels were significantly higher under the effluent treatments. Nitrate and calcium leaching increased significantly under the highest rate of N application (400 kgN/ha/yr). Spreading FDE over a sufficiently large area (15-20% of the farm) can reduce inputs of K to near maintenance requirements and restrict N inputs to about 80- 120 kg N/ha/yr, thereby avoiding potential animal health and environmental problems. A behavioural study showed that cows disliked grazing pastures recently treated with FDE. This study also showed that there was a significant and rapid decline in faecal coliform counts on pasture following effluent application. Keywords: faecal coliforms, farm dairy effluent, FDE, groundwater, nitrate leaching, pasture, soil

encouraged by many regional councils, and the use of urea fertiliser on dairy farms has increased over recent years. A 3-year trial was started in September 1997 to investigate the effects of urea and dairy effluent applications on pastures, soils and groundwater quality. Twenty-one 0.25 ha paddocks received urea or dairy effluent at rates of 0, 100, 200, or 400 kg N/ha/yr, and were grazed by dairy cows. Increasing nitrogen application rates resulted in increased pasture production and ryegrass content, and nitrate leaching to ground water. Nitrate leaching was estimated to be 14, 18, 26 and 56 kg N/ha/yr for the 0, 100, 200 and 400 kg N/ha/yr application rates respectively. No differences in these responses were measured between urea and effluent when applied at the same rate of nitrogen. Application of dairy effluent resulted in increased average pasture potassium levels from 3.65%DM to 4.00%DM, which may have implications for animal health. Application of dairy effluent also decreased soil sulphur levels and increased soil magnesium status. Keywords: dairy effluent, groundwater, nitrate leaching, nitrogen, pasture, soil, urea

The effects of 10 years of nil or maintenance phosphorus (P) fertiliser (250 kg/ha/yr superphosphate) on pasture production and composition, and on soil P status, were measured in a farmlet trial on hill country near Te Kuiti. Withholding P resulted in 29-35% less annual pasture production and 54-72% less legume (predominantly white clover) production. There was little difference in seasonality of production between the two farmlets. The loss in production in the nil P farmlet was predictable based on the decline in soil Olsen P test to 6-8 ppm and the results from past mowing trials. Additional soil measurements revealed that soil organic P levels were increasing at the site and this will have contributed to the decline in plantavailable P in soil. Re-application of P at 23 kg/ha markedly increased legume growth (by 180-330%) in the nil P farmlet, which was proportionally twice as high on steep slopes as on easy slopes. This response in legume production was most evident in summer at a time when improved feed quality is valuable for finishing lambs. Indeed, legume growth in the P re-application plots exceeded that in the maintenance P farmlet by 23-28%. This reflected reduced plant-available soil N status due to less inputs from N, fixation in the previous 10 years, and thereby increased the competitive advantage of legumes over grasses where P deficiency was diminished by fertiliser re-application. Keywords: fertiliser history, hill country, legume production, pasture production, phosphorus, seasonality, soil phosphorus