The use of plantain pasture in dairy systems can potentially reduce nitrogen (N) leaching losses via the lower N concentration in the urine (UNc) of cows. Reducing the urinary N load while cows graze pastures can reduce the risk of N leaching losses from urine patches. Research needs to demonstrate that these environmental benefits are not at the expense of milk production and farm profit. Three groups of 20 cows grazed in the following three pasture treatments: (i) plantain, (ii) plantain–clover mix (plantain, red [Trifolium pratense] and white clover), or (iii) ryegrass-white clover (wc) pastures, from spring to autumn for two years. Each year, pasture intake, diet quality, milk production and animal N (milk and urine) excretion were evaluated in spring, summer, and autumn. The cows grazing the plantain and plantain–clover mix pastures produced similar milk solids as cows grazing ryegrass–wc pasture but reduced their UNc during summer and autumn, when compared to those grazing the plantain–clover mix and ryegrass–wc pastures. Plantain reduced urinary N loads onto pastures by a greater number of urine patches with lower urinary N loading rates. The results demonstrate that plantain pastures do not diminish milk solids production from cows, and the lower UNc from summer to autumn could reduce N being lost to the environment.

Incorporating plantain with perennial ryegrass and white clover (RGWC) can improve the quality and quantity of grazing pastures; however, the sowing rate could affect the persistence of plantain, pasture yield, and nutritive value in different seasons. The objective of this study was to evaluate the effect of increasing sowing rates of plantain when established with RGWC on the dry matter (DM) yield, botanical composition, nutritive value, and bioactive compounds of the pasture over the first two years after sowing; and to determine the relationship between plantain content and nutritive characteristics in different seasons. The pasture treatments were RGWC, RGWC + low plantain rate (PLL), RGWC + medium plantain rate (PLM), and RGWC + high plantain rate (PLH). The results showed that annual DM yield was similar between treatments. The average plantain content (including leaves and reproductive stem) was 32, 44, and 48% in PLL, PLM, and PLH, respectively. The plantain composition increased in the first 15 months, then declined rapidly to about 20–30% at day 705 after sowing. Compared with RGWC, the plantain-RGWC pastures (PLL, PLM, PLH) had a higher content of organic matter digestibility (OMD), ash, starch, non-structural carbohydrates (NSC), P, S, Ca, Mg, Na, Cl, Zn, B, Co, aucubin, acteoside, and catalpol, while they contained a lower composition of DM%, acid detergent fibre (ADF), neutral detergent fibre (NDF), crude fat (CF), Fe, and Mn. These differences were linearly associated with the content of plantain leaves in the pasture and were higher in summer and autumn than in spring. In conclusion, incorporating plantain into the RGWC pasture can improve herbage nutritive quality, thus potentially increasing farm productivity and environmental benefits. However, further work is required to investigate management interventions to sustain plantain content beyond two years from sowing.

Plantain (Plantago lanceolata L.) is recognised for its ability to improve summer feed productivity as well as mitigate nitrous oxide (N₂O) emissions from grazed pastoral soils. This study aims to determine the proportion of plantain required in perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.), or RWC, mixed swards to maintain yield stability and to quantify N₂O emission reductions. The botanical composition was monitored when plantain was sown at different rates of 0%, 30%, 50% and 70% in RWC pastures under grazing by dairy cows over 2 grazing years. Urine from cows grazing RWC (6.15 g N L⁻¹), 30% (5.40 g N L⁻¹) and 50% (4.40 g N L⁻¹) plantain mixed pastures was used to measure N₂O emissions (n = 5) from the pastures of their origin and to assess the impact of the plantain rhizosphere on N₂O emissions by applying the RWC urine to the 50% plantain mixed pasture, and vice versa, in late summer–autumn using the static chambers technique. After declining in spring, the plantain content recovered in early autumn and reached a peak of 40% in the 30% plantain mixed pasture and around 50% in the 50% and 70% plantain mixed pastures in winter. A lower N content in urine, and therefore a lower urine N-loading rate from cows grazing in the 50% plantain mixed pasture, resulted in 39% lower total N₂O emissions compared to RWC urine treatment. In conclusion, 30% to 50% plantain in mixed pastures was stable throughout the 2 years, and it not only reduced the urinary N concentration in grazing cattle but also contributed to reduced N₂O EFs.

Objective: The study aimed to quantify milk production and urinary nitrogen (UN) excretion of dairy cows grazing pastures containing varying amounts of plantain (Plantago lanceolata) in different seasons, under a typical farm practice.Methods: Four pasture treatments: perennial ryegrass (Lolium perenne) – white clover (Trifolium repens) (RGWC), RGWC + low plantain rate, RGWC + medium plantain rate, and RGWC + high plantain rate, were established in four adaptation areas (1 ha each) and 20 experimental plots (800 m2 each), and rotationally grazed by dairy cows over 14 grazing events during two lactation years. In each grazing (8 to 9 days), 60 or 80 Jersey-Friesian lactation cows were assigned to their pasture treatments, adapted to their pastures over the first six days, then each group of 15 or 20 cows were randomly allocated for grazing in five treatment plots over a two or three-day measurement period. Milk, urine, and faecal samples were collected from individual cows during the measurement period.Results: The pasture treatments did not affect milk production, the yield and composition of milk solids, protein, fat, and lactose. However, cows grazing pastures containing between 17% and 28% dietary plantain reduced UN concentration by 15% to 27%, decreased UN excretion by 4% to 9%, and increased urine volume by 22% to 40%, compared to grazing the RGWC pasture. The change in UN concentration, and urine volume were associated with plantain proportion in the diet and were greater during late summer and autumn than during early summer.Conclusion: Incorporating 17% to 28% dietary plantain with RGWC pastures can reduce the risk of nitrogen losses from pastoral systems, while maintaining the milk production of dairy cows.

The objective of this study was to determine the effect of grazing plantain-based pastures on urine volume, urination frequency, and urinary nitrogen (UN) concentration of dairy cows under a typical pastoral dairy practice offering approximately 25% supplemented feeds. The experiment was a completely randomised design with three pasture treatments (perennial ryegrass–white clover (RGWC); RGWC + low plantain rate (PLL); and RGWC + high plantain rate (PLH)), five replicate plots, and repeated in two sequential grazing periods. Forty-five lactating Friesian × Jersey cows were randomly assigned into three groups of 15 animals each to graze over six days in adaptation paddocks and three days in experimental plots. Urine flow sensors were used to measure urine volume and urinary frequency, while spot urine sampling was conducted to determine nitrogen (N) concentration in cow urine. The results showed that including 25% plantain in the diet (PLH) increased daily urine volume by 44% and the daily number of urinations by 28%, compared to grazing the RGWC pasture. In addition, N concentration in cow urine was decreased by 18 and 29% when the diet contained 18% and 25% plantain, respectively. In conclusion, under a typical dairy farm practice, incorporating plantain into the RGWC pasture with the proportion of 25% plantain in the diet can increase the number of urine patches and reduce the concentration of N in the urine, thereby providing the opportunity to decrease N leaching from pastoral systems.

Plantain (Plantago lanceolata L.) has been identified by the New Zealand dairy sector as an option for reducing nitrogen losses from grazed pastures. However, there is growing concern over its poor persistence. Reports have suggested that plantain does not tolerate waterlogged soils; however, there is little scientific evidence to support those claims. Thus, the present study aimed to investigate the impact of waterlogging on plantain growth and survival. In a glasshouse, three water treatments were applied to plantain plants in pots: control (soil water below field capacity but not limited), wet (soil water marginally above field capacity), and waterlogged (water table 5 cm below the surface) for 39 days, followed by 27 days under the control watering treatment. Leaf elongation and photosynthesis were measured during the experiment. The mean leaf elongation rate of waterlogged plants was 37% lower than control plants during the stress period, but not significantly different than control plants during the recovery period. Waterlogging reduced the rate of photosynthesis in plantain leaves by 15% on average in comparison with control watering during the stress period; however, waterlogged and control plants had a similar mean photosynthesis rate during the recovery period. The results show that plantain growth and photosynthesis were significantly limited under waterlogging; however, the rapid recovery of both processes following the removal of stress suggests that important physiological functions remained intact under waterlogging, possibly due to tolerance mechanisms. These findings suggest that while waterlogging may cause limitations for plantain growth, there is no evidence to suggest that it alone could cause irreversible damage to plants and thus prevent their recovery. Rather, waterlogging stress could undermine the ability of plantain to compete with species that are tolerant of waterlogging within mixed pastures.