Defoliation Phases

• Early Defoliation

  • Grazing on pasture < 4 weeks old

  • Effects:

    • Low dry matter and nutrient yield

    • Low crude protein yield

    • High dry matter digestibility but low digestible nutrients

    • High moisture content

    • Weakens pasture stand, reducing its lifespan

• Late Defoliation

  • Grazing on pasture > 10 weeks old

  • Effects:

    • High cellulose, dry matter, and lignin content

    • Low crude protein and digestibility

    • Low leaf-stem ratio, reducing palatability

Limitations

• Overgrazing:

  • Increase in weeds

  • Weakening of pasture crops

  • Land degradation and soil erosion

• Undergrazing:

  • Increase in weeds

  • Forage wastage from trampling

  • Woody and unpalatable forage

  • Decline in pasture regrowth

  • Low plants smothered by shading

Grazing Systems in Pasture Management

1. Zero Grazing (Cut-and-Carry)

   • Animals confined in a shed; forage cut and brought to them

   • Advantages:

     • Uniform forage intake

     • Higher livestock yields

     • Reduced energy loss

     • Quick manure accumulation

     • Easier disease control

   • Disadvantages:

     • High establishment costs

     • Bedding material and disposal challenges

     • Labor-intensive and requires supervision

     • Fast disease spread

2. Rotational/Paddock Grazing

   • Grazing livestock in sections (paddocks) to allow pasture recovery

   • Advantages:

     • Breaks parasite life cycles

     • Utilizes pasture at optimal growth stage

     • Conserves excess pasture

     • Enables management operations in unused paddocks

     • Controlled grazing and manure distribution

   • Disadvantages:

     • Requires fencing and paddocking

     • High livestock numbers needed

     • Requires large land tracts

3. Strip Grazing

   • Livestock are given new grazing areas daily using movable electric fences

   • Advantages:

     • Minimizes bloating

     • Higher productivity per land unit

     • Effective pasture utilization

     • Lower construction costs than paddocks

   • Disadvantages:

     • Requires electric power

     • Incurs electricity costs

4. Continuous Grazing

   • Livestock graze freely without restrictions

   • Advantages:

     • Minimal investment required

     • High productivity with sufficient pasture

     • Simple management

   • Disadvantages:

     • Uneven grazing control

     • Difficult to manage stocking levels

     • Reduced pasture quality and quantity

     • Increased pests and weeds

     • Soil erosion risks

5. Deferred Grazing

   • Livestock are delayed from grazing until pasture is short

   • Advantages:

     • Reduces overgrazing

     • Increases stocking rate

   • Disadvantages:

     • Forage may become woody and unpalatable

     • Reduces grazing season duration

Pasture Conservation

Aims

• Preserve excess forage for future use

• Ensure continuous fodder supply to livestock

• Protect pasture from deterioration

Methods

1. Hay Making

   • Reduces moisture content of cut forage.

   • Importance: Prevents deterioration from fermentation, mold, and decomposition.

   • Moisture Content: 20% (bales), 16% (loose).

   • Procedure:

     • Cut at peak nutrient value.

     • Dry in the field for 24 hours.

     • Further dry for 48 hours before baling.

     • Stack into bales or bundles.

2. Silage Making

   • Preserves forage with high moisture content through fermentation.

   • Procedure:

     • Cut crop at the correct maturity stage.

     • Wilt to acceptable moisture.

     • Chop and fill in silo, compact well.

     • Monitor temperature and complete filling by day three or four.

     • Cover silo to prevent air ingress.

   • Effects of Too Much Air: Overheating and decomposition.

   • Types of Silos:

     • Clamp silo: Above ground with slanting walls.

     • Trench silo: Excavated underground.

     • Bunker silo: Concrete above ground with perpendicular walls.

   • Qualities of Good Silage:

     • High-quality forage, pH < 4.2, 5-9% lactic acid, free of mold and bad odors.

3. Foggage

   • Standing hay or pasture left for direct grazing during dry seasons.

   • Can be from natural or established pasture.

Factors Affecting Quality of Conserved Pasture

• Leafiness of Pasture

  • Leafy pastures yield good-quality hay or silage.

  • Woody pastures result in poor-quality forage.

• Age at Cutting

  • Cutting at peak nutrient value ensures high nutrient and dry matter content.

• Moisture Content

  • High moisture content can lead to mold and decomposition in hay and silage.

  • Excessively dry hay may break during handling, reducing quantity.

• Presence of Foreign Materials

  • Foreign materials like stones and twigs can lower the quality of conserved pasture.

• Method of Storage

  • Poor storage practices can degrade the quality of hay or silage.

• Weather Conditions

  • Difficult to prepare and maintain high-quality hay in wet weather compared to dry conditions.

• Pasture Species Used

  • Pure stands of legumes or mixed grass-legume pastures produce higher-quality feed.

  • Certain grass species are more nutritious than others.