Performance Article Series: Part 3 Other Traits Measured at Birth and Weaning

By Lance Bauer, Director of Breed Improvement & Western Field Representative

There are several other traits that are measured either at the time of birth or when calves are weaned. These include a calving ease score and udder scores at birth, then mature cow weight at weaning. These traits are important for the survival of the calf, the longevity of the cow and the efficiency of the cow. A live calf every year is the goal of most producers and having low maintenance cattle that are able to produce calves for many years are very valuable. By measuring these traits there is information provided for calculating both direct and maternal calving ease, as well as the development of new EPDs for udder scores and mature cow weights. These are all traits that are important for maternal ability and can possibly be incorporated into the calculation of $M index.

Calving ease is an extremely important trait that has a large economic value. Most producers select for calving ease by looking at the birth weight, but the birth weight is just an indicator trait of the calving ease. Calving ease is highly correlated to birth weight, but there are other factors that can influence calving ease and it is important to record calving ease scores when birth weights are taken. Calving ease scores range from 1 to 11, with 1 to 5 being the most commonly used. A calving ease score of 1 correlates to no difficulty, 2 means that there is minor difficulty and some assistance was required to pull the calf, 3 means there was major difficulty and a calf puller was used, 4 is a C-section and 5 is an abnormal presentation of the calf. These and the other calving ease scores can be found on the BBU codes reference page. Calving ease scores are used along with birth weight and other indicator traits to calculate Calving Ease Direct (CED) and Maternal Calving Ease (MCE) EPDs.

Another measure to take at birth is udder suspension and teat scores. Bad udders and teats are a large reason for culling cows and contribute to the longevity of a cow in production. The heritability of these udder traits is fairly high, as well and provides a good tool for helping decide which heifers to keep by looking at their dams. When taking udder scores there are two different variables to look at, the suspension of the udder and the teat size. The scores for udder suspension range from 1 to 9 with 1 being very pendulous, 3 being pendulous, 5 being moderate, 7 being tight and 9 being very tight. The scores for the teat size are in the same range with 1 being very large and balloon shaped, 3 being large, 5 being moderate, 7 being small and 9 being very small. An animal with an udder score of a 7-7 would have a tight udder with small teats, while one with a 3-1 would have a pendulous udder with very large balloon shaped teats. The chart at the end of this article gives examples of the different scores. These scores can help with culling cattle, helping to select replacements and can possibly be used in the calculation of EPDs.

Mature cow weight is the last trait in this article and should be taken at the time of weaning calves. This is a trait that relates to the efficiency of a cow, typically more moderate sized cows are more efficient and require less maintenance energy. This leaves more energy for the cow to expend for reproduction and the growth of a calf. When taking mature cow weights there needs to be a weight recorded, as well as a Body Condition Score (BCS) of 1-9. A body condition score of 1 is an animal that is emaciated, 3 is a thin animal, 5 is average, 7 is heavy conditioned and 9 is obese. These body condition scores are needed to help standardize the weight of the different animals in a group to the same BCS. Mature cow weight is a trait that can be used in the formation of a new EPD, as well as helping to strengthen the power of our $M index.

Recording these traits helps provide the producer with valuable tools in the selection and culling of cattle and provides information to BBU and also helps with the development of new EPDs and the strengthening of the $M index. The Beefmaster breed is known as a maternal breed and the more information that we have to help prove maternal strength the better. This data will help us as a breed to develop a larger market share in the commercial industry. These traits are all valuable to the commercial producer in terms of female production and culling criteria. The next article in this series will cover ultrasound carcass data.