Grazing refusals

Beef cattle farming Farming Dairy cattle farming

In common language, in livestock farming, a refusal is a part of the available vegetation that is not consumed by the herd.
We speak of refusals with somewhat negative connotations, suggesting the difficulties we have, or will have, with refusals.

By enriching this definition and allowing ourselves to take a more positive view, we can overcome the drawbacks of refusals and consider techniques to valorize or control them without systematically resorting to their mechanical or other elimination.

Often, this refusal will be feed for later or for other animals.

When this refusal is intended to be grazed later, it is called voluntary carry-over, not forced refusal.

When this refusal is not planned, it is observed that the vegetation becomes heterogeneous. Sometimes mechanical intervention is decided because some refusals spread and raise concerns about flora shifts. But it can be interesting to adapt techniques to get the herd to consume these plants.

Specify the nature of refusals

By taking advantage of the multiple climatic contexts, different animal species, and the diversity of livestock farming systems, it is possible to nuance and specify the situations farmers face regarding refusals in pasture.

Non-consumable plants

Non-consumable plants are not refusals. This is the case for wood, or certain highly toxic plants such as Boxwood, Bracken fern, Euphorbia species, etc., which are hardly eaten by herds, regardless of the season. It is better not to consider them as refusals, because no technique nor any herd will consume them. Beware, many plants are mistakenly considered "non-consumable" when they are potentially so (bramble, broom, coarse grasses, etc.). One can verify if these plants are consumed in other seasons, by other groups on the farm, or by other farmers…

Refusals are consumable but not consumed!

When only a part of the consumable plants is grazed, there are refusals: the level of intake by the animals at a given time or on part of the plot is less than expected.

Voluntarily programmed refusals

In this case, grazing is deliberately managed so as not to consume part of the available forage. These refusals will be grazed later in the year or the following year. This is called carry-over on the hoof because the farmer deliberately aims for their

later consumption.

Assessing the consequences of refusals left in a plot

Depending on objectives

The presence of refusals is noted. Should one worry? Should they be eliminated? How to assess if it is a problem or not? The feeling of suffering refusals should first lead us to question the success or revision of our objectives. Refusals are problematic when they reveal that we have not met our objectives.

Example: "We wanted to have the plot eaten and we did not manage to do it completely. We take the animals out of the plot thinking: Well, I will turn this refusal into a carry-over on the hoof for later."

Predictable consequences for the next use

In spring, regrowth may be reduced. The ungrazed areas in the grass will continue their spontaneous maturation. Leaf renewal will not be ensured. This is a problem if the goal is to have a strong and massive leafy growth restart. It is not a problem if the next use can accommodate this partial maturation of the plot.
Green/strawy mixes have real nutritional value. The palatability and nutritional value of this new vegetation will be

high as long as a balance between "fine" and "coarse" is maintained. It also depends on the animals' behavior and their motivation to consume this mix.

Predictable consequences for vegetation

Distinguish refusals that do not change the vegetation from those that tend to spread. Refused plants have time to store reserves, seed, and regrowth is early and vigorous… But their spread is not systematic, because vegetation can be stabilized by practices that affect the mortality of young seedlings or limit vegetative reproduction (suckers, stolons, layering…).

Rely on refusals to modify the environment. Refusals can structure the environment, create shelters, increase soil fertility, maintain freshness. Indirectly, they create a different food resource, offset relative to the rest of the plot. They provide flexibility.

Keep it clean, everywhere and all the time?

Resisting the urge or demand to "keep it clean" is difficult! It requires self-criticism and education on the agronomic interest that refusals and heterogeneous environments can present. Fundamentally, it is important to know how to explain one's agricultural and environmental objectives and the difficulties one seeks to overcome by accepting refusals in a plot (avoiding vigorous regrowth or degradation following mowing, burning, etc.), while keeping in mind adjustments in practices to remain in control of vegetation evolution.

Adapt management to avoid refusals

If refusals are problematic, how to reduce their effects? Whenever reasons are identified, different practices can be implemented to better match availability and intake. Enriching technical management allows inventing many solutions, because refusal is not determined by plants, it is the use of plants that creates refusals!

Increase instantaneous stocking density

Animal density per hectare strongly influences the expression of feeding preferences. Low stocking rates allow consumption in a "leopard skin" pattern. High stocking rates allow very homogeneous consumption.

Target a stage when refused plants are more palatable in mixture with others.

Delaying use can allow some plants to be consumed again when the grass is less green. Conversely, advancing use can allow consumption of young stages for early plants or those rich in toxins.

Modify the paddock exit criterion

Herds often tend to request a paddock change earlier and earlier. If the farmer does not resist a little, it becomes impossible to finish a paddock as desired. It may therefore be important to regain control by "firmly negotiating" with the herd the level of intake.

Reposition the salt block, water point…

Water and salt are important focal points around which the herd's social hierarchy is expressed.

They thus generate particular feeding behaviors. Very strong intake on brush, for example, can be obtained by placing a salt block in a dense thicket.

Play on the nature of feed and timing of distribution.

There are always strong interactions between what is distributed (hay, concentrate, cereals) and what the herd will take from the pasture. To limit some refusals, one can adjust the quantity distributed, favor nitrogen inputs to encourage consumption of fibrous plants, or change the distribution time (before or after grazing).

Change the paddock perimeter to motivate animals to valorize diversity.

Ruminants have a natural tendency to associate very varied plants (balance of nitrogen/fiber, large and small bites, self-medication with plants, diversification of minerals, etc.). By redefining the boundary of a paddock, or the order in a grazing circuit, one can make animals consume a plant that was previously refused.

Autres fiches Pâtur’Ajuste

Sources:

SCOPELA, with the contribution of farmers. Technical sheet of the Pâtur’Ajuste network: Refusals in grazing. April 2017. Available at: https://www.paturajuste.fr/parlons-technique/ressource/ressources-generiques/les-refus-au-paturage