Introduction

Background and rationale

The cattle industry is important to individual Albertans, and also to the economy of Alberta. Pasture and rangelands are a critical source of feed for the cattle industry, but cattle can cause a decline in pasture health through selective grazing (Teague and Dowhower, 2003). Cattle can also damage sensitive and important ecological regions through grazing, like wetlands, rivers, and streams. Rotational grazing is a management tool that producers often use to manage rangelands and the surrounding areas sustainably (Asamoah et al., 2003; Teague and Dowhower, 2003). However, rotational grazing increases the amount of infrastructure that is necessary to build and maintain (like fencing and water sources), and also requires increased labour and time to rotate animals to the next pasture - sometimes as frequently as every 12 hours.

Photo: NRCS Range and Pasture Management

Pictured here is an example of a rotational grazing system. Systems such as this are expensive in terms of infrastructure (fences) and labour (maintenance and animal management). Virtual fencing has the potential to reduce this cost for cattle farmers.

Photo: NoFence user manual

Virtual fencing may provide a solution that allows producers to balance short term cost effectiveness with long term grazing management, pasture health, and sustainability.

The NoFence (TM) virtual fence system uses the global positioning system (GPS) and a mobile app to create pastures with "virtual" boundaries. These pastures are downloaded to the virtual fence collars which are placed around the cow's neck. They use GPS to monitor an animal's location with respect to the virtual pasture boundaries, and administer audio warnings and electric shocks to prevent them from crossing the boundaries. Training is necessary to ensure that cattle learn to avoid electric shocks by turning around at the sound of the audio warning.

Virtual fencing in literature

As this is an emerging technology, previous studies on virtual fencing are generally limited in scope (number of animals) and/or length. Despite these limitations, research has shown that cattle learn to avoid shocks by reversing their direction of movement when an audio signal is heard (Keshavarzi et al., 2020; Lee et al., 2009; McSweeney et al., 2020). In addition to this, virtual fencing has been shown to effectively contain cattle in an inclusion zone or keep them out of an exclusion zone (Campbell et al., 2021, 2020; Lomax et al., 2019; Ranches et al., 2021). An important aspect of any new animal management technology is animal welfare, and many studies have concluded that virtual fencing has no effect on animal welfare (Campbell et al., 2019; Jeffus et al., 2021; Verdon et al., 2021).

Objectives and research questions

While we know from other research that virtual fencing is successful in controlled environments and on a smaller scale, there is a lack of data from trials that mimic real world conditions. The objective of this study was to asses the effectiveness of virtual fencing in Alberta and whether it might be a tool that farmers can reasonably adopt, using the University of Alberta Kinsella Research Ranch, which is a fully operational commercial cattle farm.

Specifically, the research questions this study explored are:

  1. Do cows navigate their environment and the virtual fence system by learning the relationship between audio warnings and shocks;

  2. Can virtual fencing be used to implement a rotational grazing system; and

  3. Does grazing pressure affect the success of a virtual fencing system.

Hypotheses

1) I hypothesize that the cattle will learn to navigate their environment by using audio cues to "see" where the virtual boundaries are, in lieu of visible fences. They will learn to avoid electric shocks by responding to audio cues with the desired behaviour of turning around and walking away, and thus will learn to navigate the boundaries of their virtual pastures.

Alternatively, cattle may not learn to effectively navigate their environment, even if they learn the association between an audio warning and an electric shock. Upon receiving the audio warning they may present an undesirable behaviour, such as running through the virtual boundary in the exclusion zone. The cattle may be highly reactive to the anticipated electric shock and confused about which behaviour is correct, and thus seek to escape the shock by stampeding forwards.

2) I also hypothesize that virtual fencing will successfully maintain a rotation grazing system, based on the success that other researchers have observed (Campbell et al., 2021, 2020; Lomax et al., 2019; Ranches et al., 2021). As noted previously, prior success was obtained in controlled experimental settings, which means it may not be a reliable predictor of success for our trial. As such the alternative hypothesis is that the real-world application of virtual fencing comes with too many confounding factors that increase the failure rate of a virtually managed rotational grazing system.

3) Finally, I predict that as forage supply is depleted through the grazing period (causing the grazing pressure to increase) we will see an increase in audio warnings and electric shocks, but no significant failure of the virtual fence system. At the beginning of the grazing period there is plenty of desirable forage available for the cattle to eat, grazing pressure is low, and there is little motivation for the cattle to cross the virtual boundary. As the cattle eat they reduce the amount of available forage supply, which causes an increase in grazing pressure. I hypothesize that an increase in grazing pressure will give the cattle motivation to cross the virtual boundary, causing interactions with the virtual fencing to increase. If the cattle have learned the relationship between warnings and shocks the virtual fence system should not fail.

If grazing pressure has no effect on virtual fence interactions, it could be explained by: a greater supply of forage that persists through the rotation; the motivation to avoid a shock or obtain fresh forage is different than we expected; or that cattle did not properly learn to associate audio warnings with electrical shocks.

Impact of this research

The results of this trial will be communicated to members of the cattle industry to help them decide whether to invest in virtual fencing, and to the creators at NoFence to provide feedback for what can be done better.

If my hypotheses are correct, it means that virtual fencing could be a revolutionary new tool for cattle producers. If any of our hypotheses are proved to be false, that would mean that virtual fencing from NoFence (TM), in its current form, will likely be unsuccessful in Alberta. Producers will not be interested in purchasing an expensive, new technology that has not been proven effective in grazing management.