What is the safest time for my pony to graze in summer?

What is the safest time for my pony to graze in summer? 

What is the safest time for my pony to graze in summer? 

The classic summer mix of rain, warm temperatures and plenty of sunshine can quickly cause a pasture flurry in the matter of just a few days! So, it is very important after such spells, that we take extra care and vigilance on our horses who are more vulnerable to high sugar diets 

Sugar levels in pasture fluctuate throughout the day and are impacted by numerous factors. The clock below is a generalisation of the safe, manageable and risky periods the summer pasture sugar levels can rotate through in the day. Let’s take a closer look at each period.  

Safe Zone – Green 

In the early hours of the morning, pasture has returned to its baseline level of sugars and nutrients. The photosynthetic goods it produced in yesterday’s sunlight have been converted and used throughout the pink high risk period overnight to grow and survive. In this green zone, light intensity is low, meaning that photosynthetic rate is also low. Depending on your location and time of the year, this 6am period might even be still dark! This makes the 6am-10am zone the lowest sugar content period of the day. Of course, these low sugar levels will vary between species, just as they do between feeds and types of hay! It is important to consider your individual pasture circumstances and management.  

Exceptions to consider in the lead up to summer 

• In the spring, early mornings still may produce frost or dews. Be mindful that wet grass, when eaten excessively, may cause digestive upset. If your pony has been locked up with no/restricted access to roughage overnight, they may overindulge with “grass hunger” on this grass. Providing sufficient roughage overnight, and a small feed before turnout, may help reduce this initial indulgence. 

• Also in the spring, nights can become cold enough to slow the plants metabolism and thus their processing of Non Structural Carbohydrates (NSC). This can result in some high-quality pastures holding their sugars till the temperatures increase in the morning, making the grass less desirable for vulnerable ponies.  

Management Zone – Yellow 

As light intensity increases during the day, so does the plants photosynthetic rate. The process of photosynthesis converts water and carbon dioxide into glucose (a simple sugar) and oxygen, using the light energy captured by the plant’s chlorophyll. Photosynthesis is a much-needed process in our ecosystem, but unfortunately the production of glucose does mean sugar levels will increase, making the pasture potentially unsafe for our vulnerable ponies and horses.  

The sugar content will increase throughout the day in line with light intensity and exposure, before peaking in the late afternoon. During this yellow time however, we can manage our horses intake, so as to not refuse them turnout time altogether. Management options include using a grazing muzzle, supplying alternative low sugar roughage options, or confinement in a yard where grass availability and quality is poorer (dry lot). The greener the grass, the more active the chlorophyll, likely meaning the more sugar being generated and stored!  

Risk Zone – Pink 

The risk zone in the clock, as a generalisation, begins at 5pm. But this marker is very dependent on sun intensity and time of sunset. In the late afternoon, as sunset commences, light intensity has peaked and is beginning to fall. It is a very common assumption to then correlate that sugar levels too have peaked. Whilst it is true that photosynthesis has reached maximum potential, processing the sugars doesn’t work as quickly. In fact, the pasture can take around 4 hours post complete sunset, to process all the photosynthetic products of the day. This is why the pink zone is the largest- as individual factors such as time of sunset, plant species, environment and so forth, all have tremendous effect on how long this high-risk time can last. In the depths of Daylight Savings, where the sun sets after 8pm, and days are absolutely filled with sunshine, it is very likely that stored sugar level will not meet their baselines until well into the early morning hours, meeting again at the accepted commencement of the green zone of 6am.  

If you have concerns about your ponies consumption, sugar levels or nutrition, you can reach out to our team at nutrition@ranvet.com.au for assistance, submit a diet evaluation or even book a support call.