Assorted Issues in Grazing System Design Dennis Chessman State Grazing Land Specialist USDA-NRCS, Athens, GA

Where we are going Controlled-grazing system layout Controlled-grazing system layout Heat stress Heat stress Stock water Stock water Riparian areas and limiting animal access to surface water Riparian areas and limiting animal access to surface water

How many paddocks do you need? Determined by – Determined by – Forage recovery after grazing Forage recovery after grazing Desired level of management Desired level of management An example – An example – Moving animals once a week, and allowing 35 days of rest for each paddock: 35 days ÷ 7 days + 1 = 6 paddocks

Considerations for pasture layout Ideally, paddocks should be sized for similar amounts of available forage in each. Ideally, paddocks should be sized for similar amounts of available forage in each. Square shapes are best. If possible, avoid long narrow paddocks. Square shapes are best. If possible, avoid long narrow paddocks. Design (gates, lanes, fences, etc.) should allow easy movement of animals to handling areas, and other paddocks. Design (gates, lanes, fences, etc.) should allow easy movement of animals to handling areas, and other paddocks.

Positioning gates

Considerations for pasture layout Locate water to encourage uniform grazing of the entire paddock – grazing typically decreases with increasing distance from water. Locate water to encourage uniform grazing of the entire paddock – grazing typically decreases with increasing distance from water. Nutrient distribution and soil compaction decrease with increasing distance from animal congregation areas. Managed by increased stock density and location of congregation areas. Nutrient distribution and soil compaction decrease with increasing distance from animal congregation areas. Managed by increased stock density and location of congregation areas. Cattle tend to move along fence lines  trails can develop along fences  fences (trails) that follow a slope can turn into water channels. Cattle tend to move along fence lines  trails can develop along fences  fences (trails) that follow a slope can turn into water channels.

Manure distribution in 8-acre paddocks

Manure distribution in 1-acre paddocks

The reality of paddock design

Be willing to adapt your plans Flexibility on the grazier’s part is critical. Flexibility on the grazier’s part is critical. Based on forage availability and animal needs you will need to continually make decisions about – Based on forage availability and animal needs you will need to continually make decisions about – Appropriate stocking rate Appropriate stocking rate Length of the grazing period Length of the grazing period Length of the rest period Length of the rest period Surplus forage that needs to be harvested Surplus forage that needs to be harvested Temporary fence allows more flexibility. Temporary fence allows more flexibility.

Heat stress and cattle performance Subject of lively debate. Subject of lively debate. Most of the research has been on dairy animals. Most of the research has been on dairy animals. Most of the work with beef cattle has been in feedlot environments. Most of the work with beef cattle has been in feedlot environments. Bos taurus (Angus, Hereford) are more susceptible to high temperature than Bos indicus (Brahman). Bos taurus (Angus, Hereford) are more susceptible to high temperature than Bos indicus (Brahman).

Heat stress and cattle performance Radiant energy (sunlight) increases surface and air temperatures. Radiant energy (sunlight) increases surface and air temperatures. Beef cattle in the sun vs. shade in hot environments had: Beef cattle in the sun vs. shade in hot environments had: higher internal body temperature (Mitl Ö hner et al., 2001) higher internal body temperature (Mitl Ö hner et al., 2001) increased respiration (Mitl Ö hner et al., 2002) increased respiration (Mitl Ö hner et al., 2002) increased heart rate (Brosh et al., 1998) increased heart rate (Brosh et al., 1998) lower DMI, ADG and meat quality (Mitl Ö hner et al., 2002) lower DMI, ADG and meat quality (Mitl Ö hner et al., 2002) decreased conception rates (Roman-Ponce et al., 1976) decreased conception rates (Roman-Ponce et al., 1976) Radiant energy (sunlight) increases surface and air temperatures. Radiant energy (sunlight) increases surface and air temperatures. Beef cattle in the sun vs. shade in hot environments had: Beef cattle in the sun vs. shade in hot environments had: higher internal body temperature (Mitl Ö hner et al., 2001) higher internal body temperature (Mitl Ö hner et al., 2001) increased respiration (Mitl Ö hner et al., 2002) increased respiration (Mitl Ö hner et al., 2002) increased heart rate (Brosh et al., 1998) increased heart rate (Brosh et al., 1998) lower DMI, ADG and meat quality (Mitl Ö hner et al., 2002) lower DMI, ADG and meat quality (Mitl Ö hner et al., 2002) decreased conception rates (Roman-Ponce et al., 1976) decreased conception rates (Roman-Ponce et al., 1976)

Portable shade structure

Influences on water requirement Dry matter intake Dry matter intake Lactation Lactation Activity level Activity level Age Age Diet composition Diet composition Air temperature Air temperature

Beef cattle water requirements Temp °F Gal/lb DM 500 lb calf 1100 lb dry cow 1100 lb lactating cow

Drinking water quality matters Water-borne biological contaminants Water-borne biological contaminants Blue-green algae Blue-green algae Leptospirosis (urine) Leptospirosis (urine) Fusobacterium (mud) Fusobacterium (mud) Coliform bacteria Coliform bacteria

Drinking water quality matters Chemical contaminants Chemical contaminants Total dissolved solids Total dissolved solids Total suspended solids Total suspended solids Nitrates Nitrates Sulfates Sulfates Pesticides Pesticides

Water source effect on animal performance Willms et al., 2002

Water source effect on animal performance Veira, 2003

Managing riparian areas

Livestock can destroy stream bank integrity

Benefits of riparian buffers Reduces erosion Reduces erosion Traps sediment and nutrients Traps sediment and nutrients Filters contaminants Filters contaminants Lowers water temperature Lowers water temperature Increases groundwater recharge Increases groundwater recharge Provides wildlife habitat Provides wildlife habitat

Characteristics of riparian buffers Perennial vegetation that includes grasses Perennial vegetation that includes grasses Wide enough to accomplish objectives Wide enough to accomplish objectives Controlled livestock access Controlled livestock access

Why do cattle spend so much time in the creek or pond? Most often it is related to heat Most often it is related to heat Cattle prefer drinking from troughs when given a choice (Miner et al., 1992; Sheffield et al., 1997; Veira & Liggins, 2002) Cattle prefer drinking from troughs when given a choice (Miner et al., 1992; Sheffield et al., 1997; Veira & Liggins, 2002)

Benefits to keeping cattle out of water “Everyone lives downstream” “Everyone lives downstream” Improved stock drinking water quality Improved stock drinking water quality Improved animal health Improved animal health Decreased bank erosion Decreased bank erosion Reduced sedimentation Reduced sedimentation

Limiting livestock access to surface water with structures Fences Fences

Limiting livestock access to surface water with structures Fences Fences Water ramps Water ramps

Limiting livestock access to surface water with structures Fences Fences Water ramps Water ramps Stream crossings Stream crossings

Limiting livestock access to surface water with structures Fences Fences Water ramps Water ramps Stream crossings Stream crossings Flood gates Flood gates

Non-structural approaches to limiting access Providing alternate water (McIver, 2004) Providing alternate water (McIver, 2004) Locating feeding, watering, and mineral sites away from surface water Locating feeding, watering, and mineral sites away from surface water Controlled grazing of riparian areas Controlled grazing of riparian areas

Summary Your system will be determined by the realities of your farm and your goals. Your system will be determined by the realities of your farm and your goals. Heat stress may reduce animal performance. The greatest effect will be on reproductive and high-need animals. Heat stress may reduce animal performance. The greatest effect will be on reproductive and high-need animals. Water quality affects animal performance. Water quality affects animal performance.

Summary (cont.) Uncontrolled cattle access to surface water can lead to impaired water quality, bank degradation and animal health problems. Uncontrolled cattle access to surface water can lead to impaired water quality, bank degradation and animal health problems. Animals may not be in creeks and ponds because they are thirsty. Animals may not be in creeks and ponds because they are thirsty. Animal access to surface water can be controlled through a variety of means. Animal access to surface water can be controlled through a variety of means.

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