ArticleVeterinary sciences2026
A Residual-Based Mathematical Approach to Evaluate Production-Adjusted Nitrogen Use Efficiency and Metabolic Responses in Dairy Cows.
Article in Veterinary sciences, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors.
Funding
Abstract
Nitrogen use efficiency (NUE) is commonly calculated as the ratio of milk nitrogen output to nitrogen intake in dairy cows. However, because milk nitrogen output is intrinsically determined by milk production and nitrogen intake is largely driven by dry matter intake, conventional NUE is mathematically dependent on production level and feed intake. This dependency makes it difficult to distinguish apparent efficiency caused by higher milk yield from intrinsic biological efficiency in nitrogen utilization. Therefore, this study aimed to evaluate NUE in dairy cows using a combined mathematical and metabolic framework based on residual NUE (rNUE) analysis. A total of 126 early-lactation Chinese Holstein cows were screened, and 16 high-NUE and 16 low-NUE cows were selected after matching for parity, days in milk, and dry matter intake. High-NUE cows had greater milk yield, milk nitrogen output, and NUE than low-NUE cows, despite similar nitrogen intake. They also exhibited higher ruminal microbial crude protein and ammonia nitrogen concentrations, a lower acetate-to-propionate ratio, and reduced circulating essential and total amino acid concentrations. Multiple regression analysis showed that energy-corrected milk and dry matter intake explained 71.4% of the variation in NUE. The residuals from this model were defined as rNUE, which was independent of milk production. After removing production-related effects, rNUE remained positively associated with ruminal microbial crude protein and ammonia nitrogen concentrations, and negatively associated with the acetate-to-propionate ratio and circulating amino acid pools. These findings indicate that conventional NUE in dairy cows is largely driven by production level, whereas residual-based modeling can identify a production-independent component associated with rumen nitrogen metabolism and amino acid utilization. The residual NUE approach provides a useful mathematical and metabolic framework for evaluating intrinsic NUE in dairy cows beyond milk production level.
Indexed as
Identifiers
What Socratic holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.