Many of these families have been rearing cows, and passing down their expertise in milk, for generations. Between them, they produce around 5.5 billion litres of the stuff annually, mainly from Friesian and Holstein breeds specially bred to produce milk from grass. Benchmarking a decade of holistic agro-environmental studies within the Agricultural Catchments Programme

Hanuš O, Samková E, Křížová L, Hasoňová L, Kala R. Role of fatty acids in milk fat and the influence of selected factors on their variability—a review. Molecules. 2018;23(7):1636. We have the ability to go from bench to bottle, to create a food ingredient with health benefits,” explains Nessa Noronha, director of Food for Health Ireland. The report also found that €1.1bn was invested in dairy processing plants over the past five years, resulting in an additional €340m in wages and profits for the rural economy.Firkins JL, Eastridge ML, St-Pierre NR, Noftsger SM. Effects of grain variability and processing on starch utilization by lactating dairy cattle. J Anim Sci. 2001;79(suppl_E):E218–38. Lee YJ, Jenkins TC. Biohydrogenation of linolenic acid to stearic acid by the rumen microbial population yields multiple intermediate conjugated diene isomers. J Nutr. 2011;141(8):1445–50. Wims CM, Deighton MH, Lewis E, O’loughlin, B., Delaby, L., Boland, T.M. and O’donovan, M. Effect of pregrazing herbage mass on methane production, dry matter intake, and milk production of grazing dairy cows during the mid-season period. J Dairy Sci. 2010;93(10):4976–85.

The integration of different plant species in pastures has proven to be a win-win for both the environment and the dairy cows, providing a richer diet that translates into higher-quality milk. The relationships between pasture and milk components of Irish grazing dairy farms were examined to determine if milk fat percentage was related to pasture composition, milk processability, milk composition or milk FA composition. It is generally accepted that MFD in lactating dairy cows is caused by feeding diets high in starch and low in fibre or by feeding diets high in UFA [ 7, 20, 21]. Furthermore, investigations into the causes of MFD have mainly focused on animals fed TMR diets [ 22]. However, little is known about the relationship between pasture composition and MFD in grazing scenarios [ 1]. Changes in milk composition due to cow diet were shown to impact products derived from that milk. Grass-fed butter has a characteristic golden or yellow colour due to significantly higher levels of β-carotene naturally present in fresh grass ( O’Callaghan et al., 2016a). Alterations to the FA profiles were shown to significantly affect the texture of butter ( Couvreur et al., 2006; O’Callaghan et al., 2016b) with softer butter being produced from grass-fed than non-grass-fed milk. The impact of feed systems on the sensory perception of butter was studied by Garvey et al. (2020), who found that there was no significant difference in overall preference between grass-fed and non-grass-fed butters among US, German and Irish consumers, but cross-cultural preferences were evident and likely influenced by familiarity with grass-fed or non-grass-fed butters. The impact of pasture feeding on water-soluble vitamins ( Magan et al., 2020) and metabolites ( Magan et al., 2019) in SMP indicated that vitamin B3 and B3-amide concentrations were higher in total mixed ration derived samples, while vitamin B1, B2 and B7 concentrations were significantly higher in grass-fed derived samples. Cheng et al. (2020) found that cow diet impacted the sensory perception of SMP and that perception differed between Chinese, Irish and US consumers. The impact of diet on the sensory characteristics of cheese is less clear, mainly due to the fact that significant biochemical changes occur during cheese production and ripening that likely supersede pre-existing dietary-derived differences in the milk ( O’Callaghan et al., 2017; Panthi et al., 2019). The impact of terpenes present in wild mountain pasture may, however, impact the sensory character of some regional cheeses ( Kilcawley et al., 2018). The income on a French farm was found to be only €1.24 per hour, it was €1.82 per hour in Luxembourg.Van Soest PV, Robertson JB, Lewis B. Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition. J Dairy Sci. 1991;74(10):3583–97. Weld KA, Armentano LE. Feeding high oleic acid soybeans in place of conventional soybeans increases milk fat concentration. J Dairy Sci. 2018;101(11):9768–76. AOAC, 2005a. AOAC, Method number 960.15. Moisture in animal feed. Official methods of analysis, (18th ed.), AOAC International, Gaithersburg, MD, USA (2005). Baumgard LH, Corl BA, Dwyer DA, Sæbø A, Bauman DE. Identification of the conjugated linoleic acid isomer that inhibits milk fat synthesis. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology. 2000;278(1):R179–84. Guo MR, Wang S, Li Z, Qu J, Jin L, Kindsted PS. Ethanol stability of goat’s milk. Int Dairy J. 1998;8(1):57–60.

The study took the form of once-off, on-farm investigations ( n = 94 dairy herds) gathering data on milk, grass and concentrate composition, together with an assessment of pasture and dietary management. Data was gathered by trained milk processor staff and treated anonymously thereafter, with herds identified by sample number only. These herds were located in the east and southeast of Ireland and were sampled on one occasion over 2 years. Sampling of farms was carried out in years 2018 ( n = 35) and 2019 ( n = 59) and during the months of May and June as the prevalence of MFD is high during this time of the year in Ireland ( 1). Herds used for the analysis were predominantly Spring calving, pasture-fed, Holstein–Friesian dairy herds. To be included in the study, herds had to be managed on a flat rate feeding system of between 1 and 4 kg of supplementary concentrate per cow per day. Through the Standard, Irish processors will now be able to provide proof to support the claim that their dairy products come from qualified dairy herds. Why was the Bord Bia Grass Fed Standard developed? Ruminant health research – progress to date and future prospects, with an emphasis on Irish research The dairy industry will evolve according to all these trends and, with fortifications, the possibilities are just endless.” Sandra O'Connell Mohammed R, Stanton CS, Kennelly JJ, Kramer JKG, Mee JF, Glimm DR, O’Donovan M, Murphy JJ. Grazing cows are more efficient than zero-grazed and grass silage-fed cows in milk rumenic acid production. J Dairy Sci. 2009;92(8):3874–93.

Beyond clover, the work extends to understanding the natural nitrogen release from soil organic matter. "When we have this data, we will be able to give farmers information so they can make more informed decisions around chemical nitrogen fertiliser application.” Food for Health Ireland has worked on cheese, for instance, to show that the “dairy matrix phenomenon”, the way in which its ingredients work together, means that even full-fat cheddar is not the cholesterol fiend it was previously thought to be.

DII chair Conor Ryan said that the report “showcases the remarkable success story of the dairy industry and underscores the economic contributions of our dedicated farmer suppliers and the tens of thousands of individuals employed by the sector throughout the island”. Global demand for dairy products continues to increase and this is reflected in Ireland’s milk production forecast, with a 9.2bn litre output by 2030, a 5% increase on 2022 volumes. The moderate negative correlation observed in this study between milk fat percentage and pasture PUFA content for the MMF group supports the theory that intake of PUFA, which are toxic to rumen microbes, negatively impacts rumen fermentation and hence milk fat production [ 12]. The average total FA content of pasture offered to HMF herds and LMF herds was quite low (27.4 mg/g and 26.1 mg/g respectively) and more comparable with total FA contents of diets where cows recovered from MFD rather than induced MFD. Reductions in milk fat yield by 30% were reported in dairy cows offered a diet containing 5.8% total FA with recovery achieved at a dietary concentration of 4.2% total FA [ 18]. Similarly, MFD was induced in cows at a dietary concentration of 5.5% total FA, whereas recovery from MFD was achieved by feeding a diet with a dietary concentration of 2.6% total FA [ 17]. The slightly smaller range in pasture total FA for HMF herds (13.3 to 38.9 mg/g) (S.D = 6.05) in comparison to LMF herds (13.5 to 43.5 mg/g) (S.D = 7.62) may have been beneficial in terms of improving biohydrogenation and rumen fermentation. Comparison with these studies suggest that total FA concentration of pasture in the present study may not have been high enough to negatively affect rumen microbes and cause UFA’s to be metabolised through the altered pathway of biohydrogenation. It is also, possible that pasture intake although not measured in this study, may have varied greatly between herds, resulting in very different total FA intake between herds. The pH of milk samples was measured using a portable pH meter (Phoenix Instrument EC-25 pH/Conductivity Portable Meter). The RCT was determined by modification of the method by [ 74]. Approximately 5 mL of Hansen's Naturen 145 rennet (Chr. Hansen Holding A/S, Hørsholm, DK) was diluted with 100 mL of distilled water to give a 1/20 rennet dilution. A test tube containing 5 mL milk was placed in a water bath to allow a 5 min equilibrium time to reach 30 °C. Once the samples had reached 30 °C, 0.5 mL of the rennet dilution was added, and the timer started simultaneously. The sample was slowly inverted twice, attached to a rotating holder and immersed in the water bath at a 30° angle with rotation set to maximum speed (4 rpm). The length of time taken for milk to coagulate was recorded. The milk ethanol stability test has previously been applied as a surrogate for milk heat stability [ 75]. The ethanol stability was determined using the method reported by [ 76], previously described by [ 26]. Briefly, equal volumes of the milk were mixed with an ethanol solution (ranging in concentration from 62 to 84%, v/v) at room temperature. The ethanol stability of milk was determined at the maximum concentration of ethanol solution that did not cause milk coagulation. Statistical analysis One of the key drivers behind UK shoppers’ trust in food and drink from ROI stems from our sustainability credentials as a nation,”​ Brennan said.Association of Official Agricultural Chemists and Horwitz, W.,. Official methods of analysis, vol. 222. Washington, DC: Association of Official Analytical Chemists; 1975. Production of the CLA isomers; CLA c9,t11 and CLA t10, c12, both which have been linked with causing MFD [ 12], results mainly from the biohydrogenation of C18:2c9,12 and C18:3c9,12,15. Considering the combination of both C18:2c9,12 and C18:3c9,12,15 contributed approximately 70% of the total FA content of the pasture offered to both groups, it could be expected that these isomers would exert a significant impact on the production of milk fat. However, C18:2c9,12 and C18:3c9,12,15 content of pasture offered to both groups were similar in this study. This may suggest that concentration of these FA in pasture were not associated with the reduction in milk fat percentage, again however pasture intake and hence FA intake were not determined.