Cow categories: Breakers, boners, leans and lights

The Impact of Dressing Percent on Cull Cow Marketing . . .

Cull cows that are destined to be go to the packing house are graded by their fleshiness.  The fattest cows are called “Breakers”. Moderately fleshed cows are “Boners”.  Thin cows are called “Leans” or “Lights”, depending upon the weight of the cow.  There will be price differences among these four grades. However, within each grade, large variation in prices per hundredweight will exist because of differences in dressing percentage.  Cow buyers are particularly aware of the proportion of the purchased live weight that eventually becomes saleable product hanging on the rail.  Dressing percentage is (mathematically) the carcass weight divided by the live weight multiplied by 100. 

Key factors that affect dressing percentage include gut fill, udder size, mud and manure on the hide, excess leather on the body, and anything else that contributes to the live weight but will not add to the carcass weight.  Most USDA Market News reports for cull cows will give price ranges for High, Average, and Low Dressing Percents for each of the previous mentioned grades.  As you study these price reports, note that the differences between High and Low Dressing cows will generally be greater than differences between grades.  Many reports will indicate that Low Dressing cows will be discounted up to $10 per hundredweight compared to High Dressing cows and will be discounted $5 to $6 per hundredweight compared to Average Dressing cows.  These price differences are usually widest for the thinner cow grades (Leans and Lights).  See examples from last week’s sale in Oklahoma City National Stockyards: http://www.ams.usda.gov/mnreports/ko_ls155.txt

As producers market cull cows, they should be cautious about selling cows with excess fill.  The large discounts due to low dressing percent will more than offset any advantage from the added weight.

Injection Site Swelling or Knots . . .

It is not uncommon for recently vaccinated calves to develop injection site swelling or “knots” associated with subcutaneous (under the skin) injections in the neck area. The question, or debate, from producers is whether or not this swelling affects the vaccine’s effectiveness. There is a common and erroneous misconception that these “knots” indicate that the vaccine was not effective and that buyers will discount calves with these “defects”.  However, research and industry experience has proven otherwise.

University of Arkansas Animal Science and Veterinary Medicine researchers conducted an experiment to compare the antibody immune response of 8 month old heifers that Do develop and Do Not develop visible injection-site knots and swellings after receiving a 7-way clostridial (black leg) vaccine.

The entire group of heifers was injected with a 7-way clostridial (black leg) subcutaneous vaccine. The vaccinations were given in the neck with a pistol-grip syringe using the “tented” subcutaneous technique. These vaccinations were given using strict Beef Quality Assurance (BQA) guidelines and ideal processing conditions. Almost two thirds (64.9%) of the heifers that received the 7way black leg vaccine developed visible injection site reactions (knots and swellings).

Blood samples were collected on all the heifers at the time of vaccination and again at 4, 8, 12, and 16 weeks after vaccination. The heifers with visible injection site reactions (64.9%) actually had higher antibody titers (greater immune response) on weeks 4, 8, and 16 compared to heifers without lesions or swellings. 

Consequently, the presence of an injections-site swelling or knot following a 7-way blackleg vaccination may not have visual appeal but may have positive implications for immune response and disease protection. Buyers are well aware of the neck area swelling or knots associated with some vaccine responses in calves and, in fact, often view it in a positive manner, as visual proof that the calves have been vaccinated. Buyers also understand that because the neck is a low-value area of the carcass, they do not worry about the costly trimming of injection site lesions associated with vaccines given in the rump, quarter or other high-value portion of the carcass.

The take home message is that if properly administered vaccines cause a swelling, when given under the skin in the neck and when using clean, sharp needles, don’t sweat it. Sleep well and rest assured that it is likely an indication that the vaccines is working properly and that buyers will not try to assign discounts to calves displaying these “knots”.

Meat Goat Production Classes Scheduled . . .

The Oklahoma Meat Goat Education program is a multi-session educational workshop for producers wanting to learn the basics of meat goat production. The program is a comprehensive workshop series covering such topics as animal health, nutrition, reproduction and marketing, among others.

 The first class will be on Dec. 10th, 2009 and go through February 2010, and the classes will be presented by the Johnston County OSU Extension (more details on specific dates can be obtained from the Johnston County OSU Extension Office). Cost of the class will be $25 which will include a copy of the Oklahoma Basic Meat Goat Manual.

To be a part of the class contact Johnston County OSU Extension Ag Educator Keegan Varner by Dec. 1, 2009 at 580-371-9533.

Food for Thought: “Wisdom is not the product of schooling, but of the lifelong attempt to acquire it.” Albert Einstein