Dairy Cattle Spain: North/South in different Life Satages

Advanced Assessment: Managing Complexity with `class_flex`

In this guide, we tackle a high-complexity scenario for Mature Dairy Cattle. We will split the population by geography (North vs. South Spain) and by physiological state using the class_flex column to distinguish between the Lactation Phase and the Dry Phase.

Note on File Locations: All files are located in the user_data/ folder.

📂 Folder Structure

User Files (Update these): livestock_census.csv, diet_profiles.csv, diet_ingredients.csv, livestock_definitions.csv, livestock_weights.csv, manure_management.csv.
In case of usage of the automatic cycle: reproduction_parameters.csv
Reference Files (Expert use only): feed_characteristics.csv, forage_yields.csv, mapping.csv, fao_crop_yields.csv, ipcc_coefficients.csv, ipcc_mm.csv.

Step 1: Multi-Dimensional Census (`livestock_census.csv`)

The census file links the population to a specific subregion and a physiological state. This is vital for accurate annual emission averages.

animal_tag	region	subregion	class_flex	population
mature_dairy_cattle	spain	north	dry_phase	88065.87
mature_dairy_cattle	spain	north	lactation_phase	448921.13
mature_dairy_cattle	spain	south	dry_phase	51118.64
mature_dairy_cattle	spain	south	lactation_phase	260580.36

Step 2: Phase-Specific Nutrition

The class_flex column allows you to define different forage/concentrate ratios and specific ingredients for each life stage.

A. Diet Profiles (`diet_profiles.csv`)

diet_tag	region	subregion	class_flex	forage_share	concentrate_share
diet_dairy_mature	spain	north	dry_phase	70	30
diet_dairy_mature	spain	north	lactation_phase	55	45
diet_dairy_mature	spain	south	dry_phase	54	46
diet_dairy_mature	spain	south	lactation_phase	50	50

B. Ingredient Breakdown (`diet_ingredients.csv`)

Ingredients must be assigned precisely to the subregion and class_flex. Example for the South/Lactation profile:

diet_tag	region	subregion	class_flex	ingredient	ingredient_share	ingredient_type
diet_dairy_mature	spain	south	lactation_phase	corn_national	44.85	concentrate
diet_dairy_mature	spain	south	lactation_phase	soybean_meal_44_cp	17.12	concentrate
diet_dairy_mature	spain	south	lactation_phase	corn_silage_25_30	55.00	forage

Step 3: Physiological Definitions (`livestock_definitions.csv`)

This is the most technical file. It determines the energy requirements (IPCC Tier 2). Note the difference in milk_yield and cfi.

animal_tag	region	subregion	class_flex	cfi	ca	c	milk_yield	fat_content	c_pregnancy
mature_dairy_cattle	spain	north	lactation_phase	cattle_buffalo [lactating]	stall	females	8295	3.73	cattle and buffalo
mature_dairy_cattle	spain	north	dry_phase	cattle/buffalo	stall	females	0	0	cattle and buffalo
mature_dairy_cattle	spain	south	lactation_phase	cattle_buffalo [lactating]	stall	females	9044	3.73	cattle and buffalo
mature_dairy_cattle	spain	north	dry_phase	cattle/buffalo	stall	females	0	0	cattle and buffalo

Step 4: Body Weights (`livestock_weights.csv`)

Accurate weights are essential to calculate Maintenance Energy ( $NE_m$ ) and validate the maximum physical capacity of the animal ( $DMI$ as $\%$ of Body Weight).

animal_tag	region	subregion	class_flex	adult_weight	average_weight
mature_dairy_cattle	spain	north	dry_phase	675	675
mature_dairy_cattle	spain	north	lactation_phase	675	675
mature_dairy_cattle	spain	south	lactation_phase	675	675

Step 5: Advanced Manure Management (`manure_management.csv`)

You can define management systems with high granularity, specifying the climate zone and variants for methane conversion factors.

animal_tag	region	subregion	class_flex	system_base	management_months	system_climate	system_subclimate	climate_zone	system_variant	climate_zone	allocation
mature_dairy_cattle	spain	north	lactation_phase	anaerobic_lagoon		cool	temperate	zone_wet	uncovered	wet	0.0537
mature_dairy_cattle	spain	north	lactation_phase	liquid_slurry	3	cool	temperate	zone_wet	with_natural_crust_cover	wet	0.3432
mature_dairy_cattle	spain	south	dry_phase	solid_storage		warm	temperate			dry	0.0694
mature_dairy_cattle	spain	south	dry_phase	deep_bedding	>1	warm	temperate	zone_dry	no_mixing	dry	0.0131

Step 6: Final Execution

When running the analysis, herdr will process each row as a unique “animal-state-region” combination before aggregating the results.

library(herdr)

# The model calculates impact for each phase separately
results <- generate_impact_assessment(automatic_cycle = FALSE)

Advanced Assessment: Managing Complexity with class_flex

📂 Folder Structure

Step 1: Multi-Dimensional Census (livestock_census.csv)

Step 2: Phase-Specific Nutrition

A. Diet Profiles (diet_profiles.csv)

B. Ingredient Breakdown (diet_ingredients.csv)

Step 3: Physiological Definitions (livestock_definitions.csv)

Step 4: Body Weights (livestock_weights.csv)

Step 5: Advanced Manure Management (manure_management.csv)