If you have followed this blog - or lived in Missouri - for any period of time, then you've probably heard about hair shed scoring in beef cattle. If you have, then this post will hopefully serve as a reminder that now is (most likely) the time to go out into the pastures and collect scores. I've been traveling around the state, and country, over the last 18 months or so talking about the importance of matching cattle to their environment, and hair shed scoring fits perfectly into that conversation. However, the number one question I always get is "when do I score". While the short answer is always "it depends", the long answer is "when there is the most variability in your cow herd". With the days getting longer, weather warming up, and even bringing some hefty thunderstorms along with it, early shedders are likely almost shed, if not completely shed, while others in the herd still have their full winter coat.
While hair shedding in cattle is vitally important as it pertains to heat stress during the summer, as research into
hair shedding continues, more information about its importance becomes known.
Most recently, a relationship between hair shedding in cattle and their ability
to sense change in daylight has been discovered. This suggests that cattle who
shed their winter coats earlier are more able to adapt to their environment.
For those who haven't heard much about hair shed scoring, or just need a refresher, the rest of this post will contain a high-level overview of the concept. However, at the end I am going to include some links to MU Extension publications penned by myself and Dr. Decker to give a bit more detailed information on the importance and science behind why we believe hair shed scoring to be such a critical (and easy) phenotype/trait to measure!
First and foremost, how do you score cattle? Hair shedding
scores represent a visual appraisal of the extent of
hair shedding and are reported on a 1 to 5 scale in which:
1: Cattle have
shed 100% of their winter coat. All that remains is a shorter, smooth, summer
coat.
2: Cattle have
shed 75% of their winter coat, with a small amount of hair left on their flank
and hindquarter.
3: Cattle have
shed approximately 50% of their winter coat. In addition to the hair along the
neck, this will include hair along the body, often in patchy spots.
4: Cattle have
shed only 25% of their winter coat. This will mainly occur around their neck
but may also include their topline.
5: Cattle have
shed 0% of their winter coat. Thick, longer hair still covers their entire
body.
Half scores, such as 3.5, are not reported. In
general, cattle tend to shed hair from the front to the back and from their
topline to their belly, but there is individual animal
variation in this pattern. Typically, animals begin shedding around their neck,
followed by their topline. The last spots to shed are an animal’s lower quarter
above its hock and its underline.
Other important things to consider when hair shedding include:
1. All cattle should be scored on the same day for equal comparison
2. When using hair shedding as a selection criterion, it is also important to consider the age and nutrient requirements of the female. We often see yearlings and first-calf heifers with higher hair shed scores compared to older cows. This does not mean those younger females have lower genetic merit for hair shedding. It is just a representation of all their bodies are going through growing themselves, a calf in utero, and sometimes a calf at side. If selecting replacement heifers, compare early vs late shedding only within the yearling group and not to older cows.
3. Males shed too. We often talk about hair shed scoring as it pertains to the cow herd. However, bulls also grow and shed a winter coat of hair. Since hair shedding is a moderately heritable trait, genetic change can be made by selecting earlier shedding bulls. However, when doing this, it is important to keep in mind that males do tend to start shedding around 2 weeks prior to females.
4. More and more I believe that hair shedding is an indication of how well that cow matches her environment. It is my observation that later shedding cows often have lower body condition scores. Therefore, cows that shed later in the season may be trying to tell you something. Whether they need an increased plane of nutrition, antibiotics, dewormer, the list is endless.
If you're looking for more information, or have questions about hair shedding, I encourage you to visit some of the resources available below:
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