Health, milk yield and milk quality records evaluated in 787 dairy herds before and during OmniGen-AF® supplementation to dry and lactating cows

Health, milk yield and milk quality records representing 473,711 cows from 787 dairy herds from the U.S. and Canada were collected to evaluate herd effects of feeding OmniGen-AF® (Phibro Animal Health Corp., Quincy, IL) to the entire herd. OmniGen-AF (OG) was fed at 56 g/hd/d to all dry and lactating cows for a minimum of 90 d (Post-OG). Health and production metrics were compared to the previous 90 d period (Pre-OG). Herds were enrolled in all months of the year (Jan-Mar, n = 239; Apr-June, n = 224; Jul-Sep, n = 176; Oct-Dec, n = 149) and herd size ranged from 31 to 9,046 cows. Health and production records were collected from DC305, DRMS and PCDART systems and the data were analyzed using paired t test (SAS, Statistical Analysis System) comparing the Pre-OG to Post-OG health events and production. The data were analyzed for all herds (n = 787) by herd size ( ≤ 100 hd, n = 188; 101 to 500 hd, n = 340; 501 to 1,000 hd, n = 120; ≥ 1,001 hd, n = 141). Monthly cases of mastitis, late term abortions, dead cows, and number of hospital cows/d, expressed as a % of total herd cows, differed (P < 0.001) between the Pre- and Post-OG 90 d periods (-24.6%, -28.6%, -23% and -17.4%, respectively). Health event responses to feeding OG were observed to vary by herd size and Pre-OG SCC; however significant reductions in cases/mo. of mastitis, abortions, deaths and metritis were common in all herds regardless of size and SCC during the Pre-OG period. Herds were also stratified by Pre-OG SCC cells/ml ( < 200,000, n = 309; 200,001 to 300,000, n = 237; 300,001 to 400,000, n = 146; ≥ 400,001, n = 95).The average Pre-OG SCC across all herds was 275,753 cells/ml with 73% of herds reporting a reduction in SCC during the Post-OG period. Changes in SCC were proportional to the Pre-OG SCC level. Significant reductions (P < 0.001) in SCC were observed in herds with Pre-OG SCC of 200,001 to 300,000 (-23,087), 300,001 to 400,000 (-57,850) and > 400,001 (-128,465) cells/ml. Milk production was reported by 532 herds with an average milk yield change from Pre-OG to Post-OG of +0.35 kg/hd/d (P < 0.001). Maintaining good health is a key component to cow productivity and these data suggest that feeding OmniGen-AF along with sound nutrition and management practices for dry and lactating cows can influence health, milk yield and milk quality in commercial dairies.