Berkshire 2023 progeny testing

Data formatting, checking

Author

Juan Steibel

Published

February 28, 2024

Start reading historical data and current placement data

[1] "C:/Users/marti/OneDrive/Documents/Berkshire/Prog"

Read quality data and print samples without IMF and other MQ

Meat quality data includes many spreadsheets that are imported and compiled into one single table. I took care to link all records by the ID (last 4 digitst of RFID)

Import Weight data

Weight and performance data are part of the placement file, but in a different spreadsheet. They are read, filtered for rows with missing data and prepared for fusion with other data. Again, using ID as a key for linking records.

Join placement, weight and meat quality

THis is by far the longest data wranging operation including three tables: Placement, weight and MQ. Several steps take place here:

  1. select variables in each table

  2. rename variables as needed

  3. compute ADG for the whole test period (april-august weights)

  4. Transform Share force to starprobe units using equation from ISU paper (Figure 4): Instron_kg=WBSF_KG*0.8143+3.4416, please see ABA reports Cybox folder.

  5. Compute LEA from provided data

Note: How LEA was computed: Take 2 columns from LEA spreadsheet (Dots and Initial), LEA=Dots/20+Initial. It has been confirmed by PU

Finally, raw data is saved.

Pigs per SIRE

There are at least 7 pigs per Sire. Any other eligibility criteria?

# A tibble: 6 × 2
  Sire                        cnt
  <fct>                     <dbl>
1 A3C9 Count 12-2               7
2 DHST 2 Smoked 4-2             8
3 OHK1 Midnight Special 4-6     8
4 TSS1 L12 Tex 20-7             7
5 TSS1 Lancelot 26-3            8
6 TSS2 Hollywood 3-5            7

Compare this year’s results to data up to 2022

This is important to make sure we are working in the same range for all phenotypes and that we can join data for computing correction factors.

The following phenotypes are compared between the two datasets:

 [1] "Year"             "ID"               "Pen"              "Breeder"         
 [5] "Sire"             "Gender"           "On_Test_Date"     "On_Test_WT"      
 [9] "Off_Test_Date"    "Off_Test_Weight"  "On-Test_Days"     "On-Test_ADG"     
[13] "Soundness_Score"  "Market_Date"      "Market_Weight"    "Carcass_BF10"    
[17] "Carcass_LEA"      "48h_Loin_pH"      "Visual_Color"     "Visual_Marbling" 
[21] "Visual_Firmness"  "Minolta_Y"        "Minolta_L*"       "Hunter_L"        
[25] "Thaw_Purge"       "Cook_Loss"        "Juiciness_Score"  "Tenderness_Score"
[29] "Instron_kg"       "Percent_IMF"     

The comparison is on the basis of the mean value per year and sex of the pigs in the progeny test. It is EXTREMELY important that ABA reviews these results and flag anything that may not make sense. We are on time to make adjustments as long as sire evaluations are not published.

Compare means

This table shows the mean value (average) for Barrows (B) and Gilts (G) in the current test (2023) and in previous tests.

Again: extremely important to check this.

Observations of some results:

  1. Purge larger

  2. Instron starprobe larger

I can provide a full comparison in case it is useful for a discussion.

Full comparison between years

Not showing this anymore, but it is available

# A tibble: 46 × 6
# Groups:   Phenotype [23]
   Phenotype    yr        mean    sd    Q1    Q3
   <chr>        <chr>    <dbl> <dbl> <dbl> <dbl>
 1 48h_Loin_pH  2023      5.58 0.120  5.52  5.6 
 2 48h_Loin_pH  previous  5.77 0.158  5.67  5.85
 3 Carcass_BF10 2023      1.15 0.264  1     1.3 
 4 Carcass_BF10 previous  1.08 0.304  0.85  1.2 
 5 Carcass_LEA  2023      6.74 0.985  6.25  7.2 
 6 Carcass_LEA  previous  6.99 1.19   6.15  7.75
 7 Cook_Loss    2023     21.1  3.49  18.9  22.9 
 8 Cook_Loss    previous 19.7  4.08  17.1  22.5 
 9 Hunter_L     2023     40.2  3.36  38.3  43.1 
10 Hunter_L     previous 39.8  3.81  37.2  42.3 
# ℹ 36 more rows

Full comparison between years and sexes

This table is very long, I am ommiting it now, but it is available upon request

# A tibble: 92 × 7
# Groups:   Phenotype, yr [46]
   Phenotype    yr       Gender  mean     sd    Q1    Q3
   <chr>        <chr>    <chr>  <dbl>  <dbl> <dbl> <dbl>
 1 48h_Loin_pH  2023     B      5.59  0.132  5.52  5.62 
 2 48h_Loin_pH  2023     G      5.55  0.0764 5.52  5.59 
 3 48h_Loin_pH  previous B      5.78  0.161  5.67  5.86 
 4 48h_Loin_pH  previous G      5.76  0.151  5.67  5.83 
 5 Carcass_BF10 2023     B      1.26  0.210  1.15  1.4  
 6 Carcass_BF10 2023     G      0.875 0.186  0.775 0.962
 7 Carcass_BF10 previous B      1.19  0.269  1     1.3  
 8 Carcass_BF10 previous G      0.810 0.193  0.7   0.9  
 9 Carcass_LEA  2023     B      6.52  0.912  6.05  6.9  
10 Carcass_LEA  2023     G      7.37  0.938  6.8   7.95 
# ℹ 82 more rows

Computing corrections factors and adjustments

Records need to be adjusted for sex effects. To accomplish this, for each phenotype I fit a model that includes: Sire (random effect), Off_Test_Date (random effect), Sex and Off_Test_Weight.

Everything but Sex are so called “nuisance” effects (effects we want to account for but that we are not interested in yet). Sex, on the other hand, is our effect of interest. We decide if there is a sex difference or not and then we figure out the correction factors for each phenotype such that corrected phenotypes will be comparable regardless of the sex of the tested pig.

Sex Correction factor using all data

All results are available upon request

Sex correction factors using only 2023 data

I repeated calculations of the sex correction factors for 3 datasets: 1) all data (above) 2) all data up to 2022, Used by Matt Ritter last year and not shown 3) only 2023 data (below)

General conclusion from these results: Using all data for computing sex adjustment vs using only 2023 data gives similar factors, but, as expected, the factors based on a very small dataset (2023) often are not significant and end up on a zero correction factor.

ABA should discuss this with Steibel to confirm that initial choice of using all data is still acceptable Using the sex correction factors from all data for now on.

Start to compute adjustements

Some phenotypes need to be corrected for on_test_weight or for marker_weight of the animals. Please see publication from NPPC in the Cybox folder to see an explanation for this. These are the same equations used by Stalder and Ritter in years past.

NPPC’s equations, used before for every Berkshire evaluation

  1. Adjusted ADG=ADG+0.005*(90-ON-Test-weight). Note: BF and Weight in lb
  2. Adjusted BF10=BF10+(290-Market_Weight)*(BF10/(Market_Weight-c)) note: c=30 for barrows and 5 for gilts
  3. Adjusted LEA=LEA+(290-Market_Weight)*(LEA/(Market_Weight+155))

Sex adjustments using previously computed coefficients (historical data)

Explained above. Here I include some graphics to show the effect of these corrections

Per-sire summary

In this section, I prepared the data for computing sire summaries and also corrected by year mean, which is needed for the selection indexes. This table is sortable and searchable.

Compute selection indexes using ABA index equations

Indexes are computed and joined to the individual phenotype summaries. Two tables are presented: 1) table only for indexes. 2) A wide table for all evaluated traits.

Producer-specific reports

Per-breeder individual reports are generated for all pigs that finished the test, but they are written to breeder-specific excell files for sharing with each breeder individually.