Date of Award

3-10-2025

Document Type

Doctoral Thesis

Degree Name

Doctor of Philosophy

First Advisor

Dr. Michael D. Murphy

Second Advisor

Dr. Patrick Tuohy

Third Advisor

Dr. Michael Egan

Abstract

Grazing infrastructure is a critical component of pasture-based dairy systems, yet its performance on commercial Irish farms has not been fully quantified. This thesis aimed to: (1) assess current pasture allocation practices, (2) evaluate roadway network efficiency, (3) identify factors influencing herd movement and roadway suitability, and (4) explore cost-effective strategies to reduce labour input related to herd movement. Chapter 3 assessed pasture allocation frequency and the configuration of roadway networks across 135 commercial Irish dairy farms over the grazing season of 2020. Data were gathered from PastureBase Ireland and detailed maps of each farm. The distance between the milking parlour and each paddock within the farm was recorded, while also accounting for the trips to each paddock per year. Chapter 3 identified that the number of paddocks suitable for only 12 h allocations increased from 10% for herds of less than 100 cows to 46% for herds of 250 cows or greater. The distance walked per year by dairy herds was influenced by several factors, with the most influential factor being the mean distance between the milking parlour and each paddock. The creation of the metric, RMDMP (relative mean distance from a paddock to the milking parlour) allowed the roadway network efficiency of farms to be ranked independently of herd size. Chapter 4 assessed the condition of 55 commercial farm roadway networks for their suitability for animal movement. Roadways were evaluated using several parameters and a surface condition scoring method that was validated in a controlled study prior to farm visits. The controlled study identified that roadway width (R2 = 0.96) and surface condition (R2 = 0.78) both strongly correlated with cow throughput (cows per minute). When assessing strategies to upgrade roadways on a subset of six commercial farms, total upgrades averaged €71,842.63, while a partial upgrade (surface condition only) reduced the xxi cost of upgrades to €18,039.02 (Chapter 5). The developed optimisation algorithm selected optimal roadway upgrades to reduce the labour input (h) required to move the dairy herd between grazing paddocks and the milking parlour relative to a specific capital budget. Farms with a lower RMDMP tended to have greater potential to make significant reductions in labour requirements relative to capital investments. This thesis provides a comprehensive insight into the current performance of grazing infrastructure on dairy farms, and the requirements to improve the efficiency of roadway networks on commercial farms. However, there is limited economic benefit in upgrading roadways with respect to potential labour savings, unless there is an increase in the cost of labour on farms relative to capital investment required to upgrade farm roadways.

Access Level

info:eu-repo/semantics/openAccess

Download

Share

COinS