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Reproductive Performance in United Kingdom Holstein Dairies by Geographic Region
Our objectives were to compare reproductive indicators from Holstein dairies in three regions of The United Kingdom and establish benchmarks for the 20% most efficient herds. Data from 30,112 cows and 95,326 inseminations recorded on Dairy Comp 305 software were evaluated from January to December 2014 from 111 dairies in Region 1 (R1[North; n=16 herds]), Region 2 (R2[West; n=52]), and Region 3 (R3[South; n=43]). Analyses were conducted with the MIXED procedure using herd as the experimental unit. Mean herd size (R1=252±126; R2=267±119; R3=284±156), mean daily milk production in kilograms (R1=27±3; R2=27±4; R3=28±5), days for voluntary waiting period (R1=40±5; R2=42±4; R3=40±4), days for pregnancy diagnosis (R1=37±5; R2=37±4; R3=35±5), days to reenrollment (R1=15±4; R2=15±4; R3=14±4), conception rate for inseminations after natural estrus (R1=37%; R2=36%; R3=34%), insemination risk (R1=53%; R2=56%; R3=56%), pregnancy rate (R1=19%; R2=19%; R3=20%), and percentage of cows pregnant by 100 DIM (R1=49%; R2=50%; R3=53%), by 150 DIM (R1=69%; R2=72%; R3=75%) and by 300 DIM (R1=88%; R2=91%; R3=89%) did not differ among regions. The percentage of cows bred after synchronization was lower (P<0.05) for R3 (7%) than R1 (12%), and R2 (10%) but conception rate did not differ (R1=29%; R2=28%; R3=28%). The 20% most efficient operations had mean pregnancy rate of 24%, mean daily milk production of 27±4 kilograms, days to pregnancy diagnosis of 33±5, days to reenrollment of 12±3, insemination risk of 61%, conception rate for inseminations after natural estrus of 39%, percentage of cows bred after synchronization of 7%, conception rate for inseminations after synchronization of 33%, and percentage of cows pregnant by 100 DIM of 61%, by 150 DIM of 83%, and by 300 DIM of 96%. The percentage of cows bred after synchronization was lower for the South region but no other regional differences were detected in reproductive parameters in United Kingdom dairies.
Keywords:
Fertility, Reproduction, Estrus