ADSA Research Reconfirms Health and Production Benefits of Supporting Dairy Cow Immune Function


SALT LAKE CITY, Utah (July 26, 2016) – Research presented at the American Dairy Science Association (ADSA) 2016 annual meeting reconfirms that supporting a dairy cow’s immune system through nutritional supplementation can help significantly improve health, production and milk quality.

Phibro Animal Health Corporation presented several studies that involved the OmniGen-AF® nutritional specialty product, which can be fed daily to dry, pre-fresh and lactating cows to help support healthy immune function in the face of expected and unexpected year-round stress events, including heat stress.

Heat stress studies

Research conducted at Sao Paulo State University in Brazil (Abstract 1365) involved 32 lactating Holstein cows assigned to either control or supplemented groups, balanced for previous milk production, parity and body condition. The study concluded that, under heat stress conditions, the supplemented cows had increased milk yield and dry matter intake (DMI), decreased somatic cell count and reduced incidence of rectal temperature above 39.1 degrees Celsius (102.3 degrees Fahrenheit).

In a University of Florida study (Abstract 0722), 63 cows were fed with or without 56 grams of OmniGen-AF per day beginning 60 days before dry-off through 60 days in milk. During the 45-day dry period, the cows were either cooled or heat-stressed. After calving, all cows were cooled. The research concluded that “exposure of dry cows to heat stress negatively impacts milk production in the subsequent lactation. Active cooling of dry cows and OmniGen-AF supplementation can reduce the negative effects of heat stress in the dry period.”

Related University of Florida research (Abstract 1176) demonstrated that supplementing dairy cows during heat stress not only helped to support their immune system, but also resulted in improved immune status of their calves. The research concluded that “in-utero exposure to heat stress during late-gestation negatively affects the immune and stress response of the calf ex-utero. OmniGen-AF supplementation could potentially benefit the offspring.”


Commercial dairy study

An ongoing, multi-year study (Abstract 1365) conducted by Phibro included more than 473,000 cows on 787 dairy farms throughout the United States and Canada. Cows fed OmniGen-AF for 90 days showed a 24 percent reduced incidence of mastitis, 28 percent fewer late term abortions, 23 percent fewer dead cows and 17 percent fewer hospitalized cows, compared to the 90-day period before supplementation. Nearly three-quarters of the herds also experienced significant reductions in somatic cell count.

The study concluded that “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.”

DCAD diet study

A study conducted by Cornell University (Abstract 1536) focused on the effects of reducing the dietary cation anion difference (DCAD) of the prepartum diet. Prepartum negative DCAD diets have been proven to help reduce the risk of milk fever and subclinical hypocalcemia in transition dairy cows. In this study, 89 multiparous Holstein cows were assigned to one of three prepartum diets with decreasing DCAD: Control (18.3 mEq/100g DM); Medium (+5.9 mEq/100g DM); and Low (-7.4 mEq/100g DM).

Results showed that urine calcium excretion greatly increased when cows were fed the lowest DCAD, suggesting a greater calcium flux prepartum, which likely contributed to improved calcium status postpartum.

Phibro’s Animate® nutritional specialty product has been proven to help reduce the risk of subclinical hypocalcemia when fed as part of a negative DCAD diet. Because of its palatability, Animate is readily consumed without depressing prepartum DMI, leading to higher postpartum DMI and, ultimately, increased milk yield.

For more information, visit and To view the 16 abstracts presented by Phibro at the 2016 ADSA meeting, visit

About Phibro Animal Health Corporation

Phibro Animal Health Corporation is a diversified global developer, manufacturer and marketer of a broad range of animal health and mineral nutrition products for use in the production of poultry, swine, cattle, dairy and aquaculture. For more information, visit


Editor’s note: High-resolution jpgs available by request.


Jimena Laporta, Ph.D., right, assistant professor at the University of Florida, presented the results of a heat stress study in dairy cows at the ADSA Annual Meeting in Salt Lake City. Study results demonstrated that supplementing dairy cows with OmniGen-AF during heat stress not only helped to support their immune system, but also resulted in improved immune status of their calves.

Jimena Laporta

Bob Collier, Ph.D., center, professor at Arizona State University, presented the results of a heat stress study in dairy cows at the ADSA Annual Meeting in Salt Lake City. Study results showed that OmniGen-AF reduces cortisol in heat stressed dairy cows. Here he’s discussing the research with a professor and post-doctoral fellow from the University of Queensland, Australia.

Bob Collier

Media Contacts:

Stephanie Meyers, Osborn Barr


Michelle Watts, Phibro Animal Health Corp.



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