Managing Water Needs During Grazing Periods

Technical articles - Water management, Productivity

Crop-livestock farming Dairy sheep farming Equine farming Meat sheep farming Goat farming Dairy cattle farming Beef cattle farming Farming Rotational grazing Grassland Water management

During the grazing season, it is vital to ensure the animals' water supply, both in quantity and quality. The absence or lack of water indeed leads to losses in terms of growth or milk production. While rotational grazing is an effective way to improve feed autonomy on the farm, the water supply for each paddock must be carefully planned before implementation.

Determining the herd's water needs

Regardless of the season, it is preferable to provide animals with water between 8 and 14°C. Several factors must be considered to determine the animals' water needs.

Climatic conditions :

For each species :

at 20°C, water needs increase by 30 %

• at 25°C, water needs increase by 50 %

• at 30°C, water needs increase by 100 %

Relative air humidity is also a factor that can affect water consumption : animals' water needs are thus higher in drying conditions, both summer and winter.

Feeding :

The amount of water consumed varies depending on the water content of the feed ingested by the animal.

For example, in cattle dairy farming :

The animal

Water consumption varies according to the physiological stage and milk production of the animal :

Cattle farming

In summer conditions, the above quantities should be multiplied by 1.5 to 2. Thus, an 800 kg suckler cow at the end of lactation can consume nearly 130 L of water per day during summer when there is almost no grass to graze and it is fed with forage dry feed.

Sheep farming

Water needs for different categories of animals in sheep systems (in L/kg of DM ingested)

Goat farming

For grazing goats, the water contained in the grazed grass and drunk in the barn morning and evening is sufficient to meet their needs. A drinking trough is therefore only necessary in case of high heat, or during long grazing days without returning to the barn. The presence of a drinking trough can even strongly attract goats and prevent homogeneous grazing over the entire paddock.

Equine farming

Daily water consumption varies from 15 to 60 liters on average for a 500 kg horse depending on the water content of the feed, the physiological stage of the animal or the activity performed, and weather conditions. The water needs of a pregnant (or lactating) mare are higher than those of a maintenance horse. Milk production, for example, which represents 2.5 to 3L /100 kg of live weight (LW), i.e., 12.5 to 15 L/day for a 500 kg mare, generates additional needs.

Managing herd access to water

Cows and sheep have a strong gregarious instinct : if the distance between the drinking trough and the animals' grazing area is less than 200 m, the animals will come to drink frequently, alone or in small groups. If the distance is greater than 200 m, they will come to drink less often and in large groups. This means that if the trough is too small for all animals to access it simultaneously, or if there is not enough water for all, the subordinate animals will not drink enough and will have limited performance.

In the case of rotational grazing, paddock sizes are reduced : the water point(s) are never more than 200 m away from the grazed area. It is then sufficient that 10% of the animals in the group can drink at the same time. If the distance between the trough and the farthest point of the paddock is greater than 200 m, prefer long troughs with a water reserve that allows at least 20% of the animals in the group to drink simultaneously.

The trough should not be located in a corner to avoid limiting access to only a few animals. Likewise, it should not be placed in the shade to prevent dominant animals from monopolizing access.

Regulations on the water source

Using a watercourse

Any riparian owner of a watercourse is authorized to let their animals drink there, but has the legal duty to ensure its natural flow. If trampling of the bed and banks is excessive (large herd and small watercourse), the watercourse should be protected : effectively fencing off the banks, installing a nose pump or sturdy wooden drinking troughs. River syndicates offer technical and financial assistance. Aid may be available under various schemes (PCAE, CAP, …).

Major works modifying the minor bed of the watercourse (installation of dams, modification of the longitudinal profile, culverting the watercourse to bring water to a watering point, etc.) require prior administrative authorization under water law.

Borehole

A borehole is subject to specific regulations :

If it concerns an accompanying aquifer, the borehole is considered a watercourse withdrawal and is therefore subject to the same summer restrictions.
If it concerns an aquifer reserved for drinking water supply, the withdrawal is limited to 1000 m3 per year per farm.
Water Distribution Zones (ZRE) delimit areas where water resources are chronically insufficient to meet needs. The borehole may be subject to declaration or even authorization.

To find out if your current or future borehole is subject to these regulations, contact the DDT (Departmental Directorate of Territories) of your department.

Water quality

There are no official standards for water quality intended for livestock but some recommendations. The Good Livestock Practices charter requires that animals have "regular access to a water point of adequate quality", "visually clean water, without feces, clear and regularly renewed".

When investing in facilities that improve drinking water quality, one can expect lasting benefits for the farm :

Cleaner, more accessible water : animals drink more, thus eat more, resulting in a productivity gain.
Reduced health risks (diseases, parasitism, decreased fertility, …).
Better valorization of grazing : grass consumed more evenly, more time spent grazing, better growth and reduced feed costs.

Stagnant waters should be avoided as they are sources of fecal streptococci, parasite larvae, and algae.

To limit these problems, water intake points must first be protected from environmental pollution. It is recommended to perform an analysis on any new water resource used for animal watering, and in case of disease in the herd. Note : water quality can deteriorate between the source and the trough, especially in hot weather.

It is therefore important to perform an analysis at the trough level, in mid-summer. Quality may also vary from year to year (outside the drinking water network).

Points of vigilance

Maintenance of drinking troughs : lack of maintenance leads to dirty basins that turn green and animals refuse to drink.
Water quality : if quality is not regularly monitored or if stray currents appear, animals will often refuse to drink.
Positioning : if troughs are poorly positioned in the plot (in a corner, in the shade of a tree), subordinate animals will not have access to water, leading to decreased production and higher mortality risk. Troughs may also be soiled by droppings.
Water supply flow rate : if the water flow rate is too low, waiting time at the trough will be too long.

Sources

Chambre d’Agriculture Centre-Val-de-Loire.2022.Optimizing your watering.

Annexes