Proof of Concept Beta version  
  Introduction      
  Estimating enteric fermentation related methane emissions is an inexact science as evidenced by the vastly different results from a number of calculators developed for assessment by He Waka Eke Noa.  Detailed analysis as to why there are these differences is difficult because there is little transparency as to the fundamental assumptions and how the underlying calculations are made.

There are two factors that should result in calculations being both transparent and consistent.  The first is the existence of a huge amount of research in relation to the feed  requirements of sheep, beef and dairy cattle, both breeding animals and those farmed as dry/trading stock.

The second is that there is a direct correlation between enteric methane emissions and dry matter consumption. There is therefore an objective basis for (i) estimating the theoretical feed requirements of a particular stocking configuration; and (ii) then calculating the biogenic emissions. From that, soil and manure emissions can be calculated with fertiliser undertaken separately.

THIS "PROOF OF CONCEPT" (BETA) CALCULATOR IS DESIGNED AROUND PUBLISHED FEED REQUIREMENT INFORMATION AND HAS AS ITS CORE EQUATIONS FOR ASCERTAINING THE FEED REQUIREMENTS OF BOTH SHEEP AND CATTLE, BREEDING AND DRYSTOCK.   		 
  > The first two feed requirement calculators have four equations each for illustrative purposed, covering sheep and beef dry-stock scenarios. The input information required is self-explanatory.

FYI - Entering the same start and end weight, (ie 0 Lwtg {Liveweight gain/day}) will report the maintenance feed required. 		 
      Dry stock equations >>    
  > The second set of calculations is for the feed requirements of breeding ewes that can calculate for various weights (four plus hoggets) and differing tupping dates (6). It can report on up to 5 classes of ewe and hoggets.

A unique feature of this module is that all the feed requirement assumptions are user-definable! 		 
      Ewe feed requirements >>    
   
  Enteric emissions summary  
        Number CH4 (Mg)    
Breeding ewes
Dry non-breeding sheep
Breeding cows
Dry non-breeding cattle
  Totals for year    
      CO2e  mg  
   
   
  Whole of enterprise assumptions     Y/e  
  Lw to Cw yield  
  MjME/KgDM  
 
 g/KgDM based on DMI of  KgDM /day    
  Reporting:
 
  End Kg:  
   g /day  Days
 
  MjME: DMI:  /day  
  Reporting:
 
  End Kg:  
   g /day  Days
 
  MjME: DMI:  /day  
  Reporting:
 
  End Kg:  
   g /day  Days
 
  MjME: DMI:  /day  
  Reporting:
 
  End Kg:  
   g /day  Days
 
  MjME: DMI:  /day  
  Reporting:
 
  End Kg:  
   g /day  Days
 
  MjME: DMI:  /day  
                       
                 
   
                       
   
  Whole of enterprise assumptions     Y/e  
  Lw to Cw yield The final version can have as many reporting blocks as deemed necessary. The key inputs are dates and the beginning and end liveweights. From that the App will calculate the daily weight gains and from that the feed requirements.
To assist with dates and numbers of stock sales and purchases we will develop "stock worksheets". 		 
  MjME/KgDM  
  CH4 factor  
  Reporting:  
 
  End Kg:  
   kg/day CH4:      
  MjME: DMI:      
  Reporting:  
 
  End Kg:  
   kg/day CH4:      
  MjME: DMI:      
  Reporting:  
 
  End Kg:  
   kg/day CH4:      
  MjME: DMI:      
  Reporting:  
 
  End Kg:  
   kg/day CH4:      
  MjME: DMI: CH4:  
  Reporting:  
 
  End Kg:  
   kg/day CH4:      
  MjME: DMI:      
                       
                 
                       
   
               
 
             
                               
  Tupping dates                                  
    Tupp1 Tupp2 Tupp3 Tupp4 Tupp5 Tupp6                      
  Day
15 Feb is the earliest
15 Feb is the earliest
15 Feb is the earliest
15 Feb is the earliest
15 Feb is the earliest
15 Feb is the earliest
                     
  Month
                     
  Year end                              
  Days in year                              
  Gestation                              
  Weaning   days                          
  Hill Country Loading                                
        Dry Hogget Single Ewe Hogget Twin Ewe  Hogget Triplet Ewe  
Day of Pregnancy
Days
42 55 65 75 42 55 65 75
55 65 75
    Maint        
  Stage 1 pregnancy Prd2 30    
  Stage 2 pregnancy 30    
  Stage 3 pregnancy Prd3 40    
  Stage 4 pregnancy Prd4 20    
  Stage 5 pregnancy Prd5 10    
  Stage 6 pregnancy Prd6 10    
  Stage 7 pregnancy Prd7    
  Suckling Lac   0.0    
  Mant 100% 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0    
  LACTATION S I N G L E (5kg) T W I N S (4kg) T R I P L E T S (3kg)    
    42 55 65 75 Lm (5kg) 42 55 65 75 Lm (4kg) 42 55 65 75 Lm (3kg)    
    10.1 11.4 12.7          
  7            
  14      
  21      
  21      
  Analysis based on above assumptions                              
   
                     
  Average weight 42
                     
  Ewes to ram                      
  Tupping code
                     
  Lambing                      
  Deaths                      
  Dry                      
  Triplets                      
  Ewes lambed                      
                       
  Ewes Hgts Ewes Ewes Ewes Ewes Ewes                      
    with Singles                      
    with Twins                      
    with Triplets                      
                         
    Lambs Lambs Lambs Lambs Lambs Lambs                      
   Singles                      
   Twins                      
   Triplets                      
  Total lambs                      
  MjME per head                                  
   Dry                      
   Singles                      
   Twins                      
   Triplets 0                      
  Total feed required (GjME)                                
   Dry                      
   Singles                      
   Twins                      
   Triplets                      
                         
  MjME / KgDM                      
  KgDM                      
  CH4 @ 21gm/kgDM (Mg)                      
  CO2e (Mg)                      
  Kg/head                      
                                     
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  Assumptions                      
    Year end                    
    Gestation  days                  
    Default calving
                 
    Calving date To be expanded to separate date settings for 8 classes.            
    Bull to cows            
  Birth kg - males  mother's KgLw                
               - females  mother's KgLw                
    Weaning days                  
  Maintenance MjME required (base 400kg)                
  Easy Hill                    
  Flat                    
  Hard Hill +                    
  Per 100kg                    
  Pregnancy MjME required based on calf birthweight            
  Birth kg  /  Days 28 28 28            
  Pregnancy Pr1 Pr2 Pr3 Pr4              
  30 kg            
  40 kg            
  50 kg            
  Table interrogation                    
  Pregnancy Average            
  Birth weight              
  MjME pd            
  Total MjME            
  Lactation - cows and calves MjME                
  Days 60 60 60            
  Weaning kg MJME/cow+calf/day Average            
  150            
  200            
  250            
  300            
  Lacation MjME as per Table                
  Weaning kg
                   
  MjME pd                    
  ANALYSIS                      
  Weight    
 
  Terrain (Flat/Hill)    
 
  Maintenance feed      
  Birth weights Male  
    Female   
    Males %    
    Average    
    Alternative    
  Pregnancy feed      
  Pregnancy rate      
  Weaning weight    
 
  Lactation feed Days  
  Calving rate      
  Weight loss/gain     30 30 30 40 45 35 30 35  
  Feed required    
  Annual feed MjME      
  MjME per KgDM      
  KgDM/hd per day    
  Annual CH4 emissions @  
  Numbers as at 1/7/2020    
  Total CH4 emissions (Mg)