Production of an equine anti-bovine leukocyte serum.

This study discusses the method of producing an equine anti-bovine leukocyte serum (EABLS) using leukocytes from irritated bovine udders. The procedure applied includes a series of subcutaneous and intravenous injections in horses and the effects were gauged through various changes in serum protein and albumin/globulin ratios. The varying effects of the EABLS, especially its capacity to induce neutropenia, were also tested on different cows and calves.

Creation of EABLS

• Equine anti-bovine leukocyte serum (EABLS) was created using leukocytes harvested from the milk of cow’s udders. This harvesting was done after the udders were irritated with endotoxin to stimulate the production of leukocytes.
• These isolated leukocytes were then used as antigens which were introduced to two horses through a series of subcutaneous (under the skin) and intravenous (into the bloodstream) injections.

Effects of EABLS Production on Horses

• After the administration of the antigens, a progressive increase in total serum proteins was observed in the horses.
• Changes were also noted in the albumin/globulin ratios, with a decrease being noticed after the injections. The most notable change was an increase in beta2-globulins, which are a type of protein in the blood.
• Using Ouchterlony analysis, which is a laboratory technique used to examine the reaction between an antigen and an antibody, an increase in the number of precipitin lines was identified. This was in line with the elevated production of antibodies against the bovine leukocytes.

Testing on Cows and Calves

• The EABLS was then tested on four mature cows and two calves. They were intravenously administered with a dose of 50 ml for cows and 20 ml for calves.
• Some were given heated EABLS while others received the unheated version. This distinction is important as heating can often neutralize certain types of biological substances.
• The results showcased a marked neutropenia, or a reduction in the number of white blood cells, primarily noted within the 1st hour of the injection. This was most pronounced in the two calves and two cows given heated EABLS.
• However, it’s also important to note that not all animals developed neutropenia, hinting at a variability in individual susceptibility to EABLS.