Bovine Leukosis Virus

 Curious Jersey Cows

This article is part of our series of original articles on emerging featured topics. Please check here to see other articles in this series.

Bovine Leukosis Virus, also sometimes referred to as “Bovine Leukemia Virus” or BLV has been recognized as a cancer-causing virus in cattle for over 4 decades. Despite widespread distribution in the United States, the virus usually has a minor economic impact on commercial dairies and has thus been ignored while attention is focused on more obvious …

Simplified Scoring System to Identify Respiratory Disease in Dairy Calves

Bovine respiratory disease (BRD), also known as shipping fever or pneumonia, is a significant problem for dairy replacement heifers. According to reports from the National Animal Health Monitoring System (NAHMS), 18.1% of pre-weaned dairy heifers experienced respiratory disease (USDA 2012), but respiratory problems accounted for 22.5% of deaths in unweaned heifers and 46.5% in weaned heifers (USDA 2010). That means respiratory disease is the single greatest cause of heifer deaths after weaning. Long term effects on performance include decreased probability …

Heat Stress Management of Dry Cows

Sprinkler head in free stall barn

This article is part of our series of original articles on emerging featured topics. Please check here to see other articles in this series.

Heat Stress Affects Health and Production

Heat stress during late gestation negatively influences health and productivity of dairy cows in the subsequent lactation1,2. Under commercial farm conditions in Florida, cows that were dry during the summer months (June, July and August) produced less milk during the subsequent lactation compared with all cows dry during …

Issues Related to Subacute Rumen Acidosis (SARA) in the Dairy Cow

This article is part of our series of original articles on emerging featured topics. Please check here to see other articles in this series.

The dairy cow has a great ability to achieve high levels of feed intake relative to body size while maintaining a rumen fermentation environment within certain physiological limits. These limits facilitate a favorable symbiotic relationship between the ruminant host and rumen microorganisms. The ruminant host should provide the microorganisms an environment of limited oxygen, relatively neutral …

Five Steps to Designing the Ideal Transition Cow Barn



Over the last …

Impact of Milk Fever and Hypocalcemia on Reproductive Performance of the Dairy Cow


Cow Comfort and Health


The dairy expansion era in North America, which gathered pace throughout the ’90s and continues to this day, has resulted in the migration of dairy cattle from traditional tiestall and stanchion barns to the freestall facility, which has emerged as the dominant form of dairy cattle housing worldwide.

The basic premise of milking more efficiently through a parlor, while being able to keep larger groups of cows together in management groups in larger herds, is sound from a …

New Developments in Understanding Ruminal Acidosis in Dairy Cows


Maximizing milk production without incurring ruminal acidosis is a challenge for most dairy producers. Feeding a highly fermentable diet provides energy precursors needed for high milk production, but the risk of subacute ruminal acidosis (SARA) increases. Ruminal acidosis is characterized by periodic episodes of suboptimal rumen pH, which depresses fiber digestion and possibly milk production. Preventing SARA requires careful management of rumen fermentation. Key strategies that help reduce the risk of acidosis are adaptation of the rumen environment to …

Prevention of Udder Edema in Dairy Cows


The periparturient period is especially important for the health of dairy cows. Among health problems occurring during this period is an accumulation of excessive interstitial fluid in extravascular spaces of the udder and adjacent tissues of some animals. Occurrence of udder edema varies greatly in different herds, with incidences ranging from 18 to 96% of all cows observed at calving (Al-Ani and Vestweber, 1986). Although the swelling usually diminishes after parturition without special care, management problems and permanent damage …

Adult Dairy Cow Mortality


How big of a problem is dairy cow mortality in the U.S.?

Key points:

-The frequency of adult dairy cow mortality appears to be increasing.

-Cow mortality is important both economically and as an