Phenomics

Conducting grazing performance testing using technology to determine individual dry matter and water intake.

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Abstract

Collecting phenotypes for individual dry matter intake (DMI) and water intake has advanced in recent decades with the use of precision livestock farming approaches. These intake systems are found in drylot facilities where rations are delivered to the bunk. However, the overwhelming majority (~85%) of the U.S. beef herd is grazing or consuming harvested forages. Historically, individual grazing DMI has been too difficult to determine accurately at the scale needed to conduct genetic evaluation. This had led to estimates of grazing DMI based on book equations, largely derived from data collected in the dry lot. We have recently developed an approach to determine individual daily dry matter intake at scale. This approach involves using a long short-term memory (LSTM) -based model developed with grazing DMI ground truth data to leverage a much larger dataset from animals fed in the dry lot. We use measured body weight, water intake, water intake behaviors collected using Vytelle SENSE systems along with climatic data collected from the nearest National Oceanic and Atmospheric Administration weather station. The LSTM was developed with records from 2,143 animals (n=108 grazing animals). The LSTM produced RMSE = 1.329 kg·d⁻¹ with R² = 0.655, while Nutrient Requirements of Beef Cattle equations produced RMSE = 1.858 kg·d⁻¹ and R² = 0.326. The LSTM was externally validated by withholding a portion of the grazing dataset and with an external, non-regional dataset from a drylot. We have begun using that approach to collect phenotypes from potential replacement heifers using Vytelle SENSE modules integrated with mobile in-pen weighing units and trailer-mounted flowmeter-based water intake systems. In 2024 and 2025, 67 and 75 heifers respectively were grazed under this setup as part of data acquisition. These heifers represented the potential replacement females for the West Virginia University herds. In 2024 heifers averaged 8.41 ± 0.13 kg of DMI and 30.9 ± 1.8 l of water intake. In 2025 heifers averaged 4.65 ± 0.01 kg of DMI and 24.6 ± 1.16 l of water intake. In 2024 the range in DMI was 6.73-12.0 kg and in water intake was 20.4-64.5 l. In 2025 the range in DMI was 4.32-5.01 kg and in water intake was 11.27-69.94 l. The average daily gain of heifers in 2024 was 1.15 ± 0.15 kg and in 2025 was 0.74 ± 0.05 kg. We were able to calculate individual residual feed intake and residual water intake for all heifers in both years. Although many more records are needed, evaluating potential replacement females in the environment and system in which they will need to perform as cows has great potential to drive improved efficiency in the U.S. beef herd.

Keywords: 2026

How to Cite:

Yost, T., ArunKumar, K., Gillespie, J., Thekkoot, D., Osterstock, J. & Wilson, M., (2026) “Conducting grazing performance testing using technology to determine individual dry matter and water intake.”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2286184. doi: https://doi.org/10.31274/wcgalp.23874

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