How to develop annual herd level lactation curve
As an illustration, This figure shows several lactation curves resulting from different lactation curve characteristics. If only magnitude increased, the overall height of the lactation curve would be increased. Increased time to peak yield resulted in a longer time to peak and lower peak yield. Higher persistency solely resulted in a higher peak yield and a slower decline rate after the peak.
The total number of cows increased from 2008 to 2016, then steadily decreased thereafter. In general, over 11 years the number of herds declined, accompanied by larger herd size and higher milk production.
Descriptive statistics of herd lactation curve characteristics when using End Year as the partitioning method
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