What is 305AA and how does it differ from 305ME?

7 min

summary the council on dairy cattle breeding (cdcb) and usda introduced a new standardized milk yield metric called 305 aa in 2024 to better reflect modern cows and farming practices this update improves accuracy by standardizing production to a cow at 36 months of age instead of the older mature equivalent (me) model 305aa uses updated adjustment factors based on recent research covering age, breed, seasonality, and region the factor is updated for each lactation, and the 305aa is updated for each testday you can view 305aa values in both dairycomp and pulse to compare them against traditional 305me data while dairycomp continues to use 305me for cowval and relv calculations for now, having both metrics side by side allows you to see how modern adjustment factors affect your herd's projected yields researchers analyzed over 100 million lactation records and the new metric reflects advances in genetics, climate, and management since the 1990s distinctions factor 305me 305aa standardization age mature equivalent (61 86 months depending on breed) 36 months (fixed age) climate regions 3 geographical regions (east to west across u s ) 5 climate based regions breed adjustments calculated with season region; heavily influenced by holsteins breed specific age parity adjustments using broader dataset last updated 1994 2024 (based on 1960 2022 data) dataset size limited by 1990s computing 101 5 million milk, 100 5 million fat, 81 2 million protein records milking frequency adjusted to 2x milking adjusted to 2x milking (unchanged) days open adjustment included included (unchanged) important 305aa is calculated/displayed dynamically in pulse and is not physically stored in the testday record 305aa can only be applied to pulse connected herds that receive testday reports from a drpc dairycomp cowval and relv calculations were not updated; they continue to use 305me if aafac is missing for an animal, 305aa defaults to 305m (no adjustment applied) where can i check 305aa details? testdays if your dairy imports testday data to pulse, you can check 305aa results as the following items 305aa projected 305 day yield based on testday data aa305 projected 305 day yield based on daily milk \pulse only\ 305aa fat age adjusted fat production \pulse only\ 305aa protein age adjusted protein production see testdays docid\ ezdiewyrexxlqvuai8k 2 to learn more about viewing mature equivalent data in pulse cowcards customize your cowcards to view the new aa items alongside traditional me values see view animal details on cowcards docid\ z4i4tjlwgg4x5bnems 6 to learn more about working with cowcards in pulse dairycomp go to alter10 cowcard definition docid\ mx w0 rojbf tkitdbpql and testdays tab docid\ p3jj9kjdee0buqhtc 0j9 to add 305aa to your cowcards and testdays table dairycomp will automatically upgrade your cowfile to version 10 if extra space is needed how is 305aa calculated? pulse calculates 305aa by applying an age adjusted factor (aafac) to a cow's actual milk yield this factor is derived from the latest cdcb/usda methodology, which considers the cow's age, parity, breed, and the specific climate region of your dairy for on premise dairycomp to include 305aa items, you must first have pulse connected to your herd and be actively receiving testday reports from a drpc contact us docid 4ghs 95g97ps fckkm8su if you have dairycomp, but are not yet connected to pulse after the connection is confirmed, dairycomp processes 305aa by integrating three aa items and calculation logic that mirror the existing 305me structure but utilize the updated cdcb factors calculation details aafac age adjusted factor based on cdcb/usda methodology \pulse only\ aafat age adjusted fat factor \pulse only\ aafat age adjusted fat factor 305aa = 305m × aafac aa305 = daily milk × aafac \pulse only\ 305aa fat = 305fat × aafat \pulse only\ 305aa protein = 305pro × aapro how is 305aa applied to regions outside of the us? the usda’s climate region assignments were developed for us states to extend the new age adjustment factors to international customers, vas applied the same climate analysis method to non us locations the approach is based on the concept of average degree days (heating degree days (hdd) and cooling degree days (cdd)), which is a representation of outside temperature data see eia gov https //www eia gov/energyexplained/units and calculators/degree days php to learn more about degree days what if i already have 305aa or aafac items in my dairy? if an item with the name "305aa" or "aafac" already exists in your cowfile, dairycomp will log a message in the activity log rather than overwriting it in these cases, contact us docid 4ghs 95g97ps fckkm8su to ensure the items are mapped correctly to the new standard definitions want to learn more about 305aa? see the vas article understanding 305‑aa https //vas com/blog/305aa standardized yield metric in dairycomp/ and cdcb's article introducing 305 aa https //uscdcb com/introducing 305 aa the new standardized yield measurement/