Milk production and its control are of great importance in mammalian species. Dairy cattle have undergone intense selection for quantitative traits that increase milk production.  Considerable research goes into understanding the physiological factors which regulate milk synthesis in hopes of further enhancing efficiency of milk production. 

Atresia coli is a developmental abnormality in cattle that is lethal without surgical correction. The inheritance of atresia coli remains controversial and not completely understood.

It is necessary to determine the extent and nature of absorption of Lf by the newborn calf before further studies can be conducted to determine if the absorbed Lf has an effect on the neonate.  The objective of this study was to characterize the absorption of Lf into the calf's blood after feeding colostrum.

Fatty liver (hepatic lipidosis) is an important metabolic disorder of high-producing dairy cows. Clinical tests that assess liver function and the severity of hepatic lipidosis in cattle include sulfobromophthalein (BSP) and caffeine clearance tests, percutaneous liver biopsy followed by microscopic examination or assessment of buoyancy in copper sulfate solutions of varying specific gravity, the propionate loading test, assessment of serum sorbitol dehydrogenase, aspartate aminotransferase, gamma-glutamyl transferase, and alkaline phosphatase activity, and determination of serum total bilirubin and bile acid concentrations. Each test has advantages and disadvantages in assessing liver function in dairy cows.

Dairy managers must be ready for the meet the energy challenges of the next millenium.  But, are your dairy cows ready for the Y2K energy challenge?  Energy shortages will shut down your dairy herd. 

The concept of feeding fat to dairy cows to minimize the energy deficit during periods of high milk production is not new. However, trying to determine the amount of fat to add to the diet is not always easy. The use of computerized ration formulation systems will not help since no known system does more than sum the amount of fat added. However, recent research data may begin to tell us how much and what type of fats can and should be added to diets to maximize the response in milk production.

A related project examined the effects of propylene glycol supplementation on the metabolism of Jersey cows.  This study was designed to determine the response of dry matter intake, milk production, milk components, body weight, and body condition score in propylene glycol supplemented Jersey cows.

Optimal contents of protein in milk replacers remain controversial.  Because protein is the most expensive component of milk replacer, it may be desirable to feed an amount of protein that supports satisfactory but not maximal growth at a given feeding rate. 

The objective of our research was to investigate a method to collect objective measurements on  the rear legs of dairy cows in order to get a more accurate description of the rear leg conformation compared to subjective linear scores.

With near record milk prices in 1998 and low feed costs, Illinois dairy managers had a chance to catch up with solid management and financial planning. Dairy manager need to look back to see how their business has changed, look at 1998 to see how their business competed, and look ahead to evaluate future business strategies.

Inherited deficiencies of Factor XI, a blood clotting factor, have been documented in humans, dogs, and cattle.  The bovine disorder has been known since 1969 when it was discovered in Holstein cattle in Ohio. Characterized by hemophilia-like symptoms, it was later observed in Holstein-Friesians in Canada, England, and Australia.  Like DUMPS and BLAD, it is inherited in an autosomal recessive manner.  Accordingly, carrier animals (heterozygotes) for the defective gene appear to be outwardly normal, while affected animals (homozygotes) have a bleeding disorder; one quarter of offspring from mating a carrier bull to a carrier cow are expected to be affected with Factor XI deficiency.

As environmental temperatures increase, the dairy cow responds in several ways.  Responses to thermal stress include behavioral and physiological adjustments, increased water intake, reduced feed intake, and concomitant reductions in milk production.  Less understood is whether high- and low-producing cows are affected by heat stress at the same environmental temperature.  Our objective was to compare the responses to increasing temperature of high- and low-producing Jersey cows, and to study whether milk production influenced the point at which responses to heat stress start to occur.

Soybean meal, heat processed whole soybeans, and soybean hulls are the major soybean products used for feeding dairy cows. They have a nutrient content that is complementary to cereal grains such as corn, which makes this an excellent combination of feeds for dairy cows.

The monitoring process is commonly the weakest link in most mastitis control programs.  Yet, the success of any control program rests on the ability and desire to monitor progress.  This paper will focus on methods to troubleshoot somatic cell count (SCC) problems.

During times of energy deficit, animals break down triglycerides (fat) stored in adipose tissue. The resultant nonesterified fatty acids (NEFA) enter the blood stream to be transported to organs and tissues throughout the body.  The concentration of NEFA measured in blood has been shown to reflect fat mobilized from body fat reserves.  Elevated NEFA levels indicate that dietary energy intake is insufficient for the cows needs for milk production or fetal growth and that body fat is being broken down to supply the energy deficit.  Researchers at Michigan State University found that increased NEFA during the late closeup period were associated with greater incidences of ketosis, displaced abomasum, and retained fetal membranes, but not milk fever, around calving.  Extensive and prolonged mobilization of body fat as reflected by increased NEFA concentrations and loss of body condition generally leads to fat accumulation in the liver (hepatic lipidosis or fatty liver).