Urine and fecal excretion patterns of dairy cows divergent for milk urea nitrogen breeding values consuming either a plantain or ryegrass diet

Abstract

Environmental degradation has been attributed to inefficient nitrogen utilization from pastoral dairy production systems. This degradation has especially been associated with the urine patch, which has been identified as a key component of nitrate leaching to waterways. However, a lack of information exists regarding the pattern of urination events and individual urination characteristics across the day, which would help inform strategic management decisions. The aim of this study was therefore to evaluate and report the patterns and characteristics of fecal and urination events throughout the day for cows divergent for milk urea nitrogen breeding values (MUNBV) on either a plantain [Plantago lanceolata L. (PL)] or ryegrass [Lolium perenne L. (RG)] diet as ways to reduce environmental impact. Sixteen multiparous lactating Holstein Friesian × Jersey cows divergent for MUNBV were housed in metabolism crates for 72 h, with all excretion events captured and analyzed. Cows selected as low for MUNBV consistently had a 65.2-kg lower urinary urea nitrogen (UUN) load (kg/ha) than high MUNBV cows for all hours of the day when consuming RG. The association between lower urinary urea loading rates and less N leaching implies a reduced environmental impact from low MUNBV cows consuming RG. When cows consumed PL, regardless of MUNBV, they had on average a 137.5-kg (UUN/ ha) lower loading rate compared with high MUNBV cows on RG and a 72.2-kg (UUN/ha) lower loading rate compared with low MUNBV cows consuming RG across the day. Cows on PL also exhibited a different diel pattern of UUN load compared with cows consuming RG. Differences in the diel pattern of N excreted in feces were also detected based on MUNBV and by diet, with low MUNBV cows excreting on average 3.06 g more N in feces per event for the majority of the day compared with high MUNBV cows when consuming RG. Lower UUN loading rates and more N excreted in feces indicate a potentially lower environmental impact from low MUNBV cows when consuming RG compared with high MUNBV cows. The use of the PL diet also resulted in lower UUN loading rates and greater levels of N excreted in feces compared with RG, therefore also indicating its ability to reduce environmental impact compared with RG.

Dietary and Animal Strategies to Reduce the Environmental Impact of Pastoral Dairy Systems Result in Altered Nutraceutical Profiles in Milk

“…Only results about dietary and milk metabolomic attributes are reported here. Readers are referred to Marshall et al [ 4 ] for milk production, N and water balance results, and Marshall et al [ 44 ] for diel N excretion pattern. Herbage chemical characteristics, botanical composition, and DMI values have been reported previously [ 4 ].…”

Implementing plantain (Plantago lanceolata) to mitigate the impact of grazing ruminants on nitrogen losses to the environment: A review

“…Nitrogen concentration in urine from ruminant livestock decreases by 13%-75% as PL inclusion in the animals' diet increases (Box et al, 2017;Minnée et al, 2017;Minnée et al, 2020;Navarrete et al, 2022;Navarrete et al, 2023;Nkomboni, 2017). In a metaanalyses of studies, Nguyen et al (2022b) The greater urine output is associated with more frequent urination events per animal per day (Mangwe et al, 2019;Marshall et al, 2022a;Minnée et al, 2020). The dilution effect of PL has also been observed in sheep (O'Connell et al, 2016) and red deer (Cervus elaphus L., Beck et al, 2020).…”

Nutrición animal: Texto de formación universitaria

“…La avicultura es uno de los métodos de cría de animales más eficientes y proporciona seguridad nutricional a un número significativo de la población mundial; sin embargo; sin embargo, genera una huella ambiental significativa por los materiales de desecho, como la basura y el estiércol de las aves de corral (Gržinić et al, 2023). El uso ineficiente del nitrógeno de los sistemas de producción lechera al pastoreo contaminan el medio ambiente, asociados con los parches de orina (Marshall et al, 2022). La ganadería intensiva impacta negativamente el medio ambiente al contribuir a la liberación de amoníaco y óxido nitroso, la contaminación de las aguas subterráneas por nitratos y la eutrofización de ríos y estuarios (Samanta et al, 2022).…”