May 30, 2015

What's Wrong with Grass-Fed Cattle?

I wasn't planning on making a blog post about grass-fed cattle anytime soon, but a comment by a cyber-acquaintance on a livestock forum gave me a good mental boost on what I should make my next blog post as.

So, I am sitting here asking or challenging you to consider what is wrong with grass-fed beef? Grass-fed cattle or grass-fed beef is a nice term to think about when wanting to live and eat more sustainably or more "green," but it's a term that is over-used and abused to the point that consumers no longer understand what it really means, nor what the concepts entail.

The whole idea of grass-fed cattle is basically raising cattle solely on grass. Grass-fed beef is ready-to-serve beef (muscle tissue "harvested" from a bovine after slaughtering and butchering) that comes from cattle that have been raised and finished on grass.

Now here's where I'm challenging you to fire your brain-cells up and consider the Devil's Advocate about grass-fed because there is actually something inherently wrong with it, and it's something that many people don't consider.

The problem with grass-fed is all to do with nutrition and energy, and it's not just the grass that's to blame, it's the cattle as well.

The Thing About Grasses

What many people don't understand is how energy and nutritional levels fluctuate with grass growth. There are certain stages of grass growth where nutritional levels for cattle are considered optimum, and other stages where it's going to be mostly water or mostly fibre and little else. Grass isn't green all year round and pasture grass certainly isn't grown nor maintained in the same manner as lawn grass. Pasture grasses often are not irrigated regularly, nor are evenly trimmed down with a mower. They are comprised often of different species that are often not grown in lawns, and each grass species has different nutritional levels, just like different types of vegetables found in your grocery store have different levels of nutrients.

When I use the term "nutrient[s]," I'm referring to these major nutrients: Energy (carbohydrates), protein, vitamins and minerals. But I'm emphasizing the importance of energy, because it is energy (and some protein) that primarily affects an animal's performance.

For most grasses, the best growth stage to graze grasses is when they are still "vegetative" (are all leaf) and have not yet had a seed head emerge and begin to flower. This is because once the grass inflorescence (fancy word for "grass flower") emerges, all the grass's energy and nutrient levels get pushed into this structure so that it can flower and produce seeds meant to grow into new plants once they fall off or are eaten by animals. The leaves die off from the tips to the stem, and the plant dies once it has set seed.

When grasses emerge from dormancy, they are relying on the energy stored in the roots to get them going until they can begin to photosynthesize on their own and put energy and other nutrients, including carbon, back into the roots and soil. Grasses won't begin full photosynthesis until they have a couple of leaves emerged, but even then nutrient levels aren't at where a producer would like to see some gains in his animals. For most graziers, they would like to see cattle put out on pasture when grass has reached at least the four- to six-leaf stage, or when plants are over 10 to 12 inches tall. This is when nutrient levels are optimum for cattle to glean for their own bodies.

When grass is allowed to go past this stage, nutrient levels decline. The amount of energy and protein that cattle can get from tall, vegetative forages declines when the seed head emerges and the plant puts all its effort into reproduction and seed propagation. By the time it dies or senesces, the grass plant is mostly fibrous tissue, and little else except what can be nipped off from the seed heads.

It's not all that beneficial to have pastures that have only grasses anyway, there is always a need to incorporate legumes like alfalfa or clover in forage stands in order to increase nutrient levels of the forage sward. Other legumes like bird's foot trefoil, sanfoin, and cicer milkvetch are also excellent to have in a pasture.

The Thing About Cattle

We all know that cattle and grass go together like bread and butter, but the thing about cattle and grass is that cattle are not adapted to subsist on grass alone. Cattle need more than just grass to live, function, reproduce and keep in good condition.

In terms of energy, cattle put their own bodily needs ahead of that for lactation, reproduction and growth in that order. Maintenance is most important, and will take priority when energy intake levels are too low for an animal to grow or put energy into reproduction. When energy levels are too low, the animal will pull fat reserves from its own body in order to continue to live and function. This can only go for so long before it turns into a concern of animal cruelty and death by starvation or malnutrition.

This is the primary concern regarding cattle on a "grass-only diet." Beef cattle tend to do better on such a diet because they are better adapted for life on more of a coarser diet with more fibre and limiting energy levels. However some beef cattle--and breeds--may not fare so well, and may be prone to lose weight on grass. Dairy breeds are especially notorious for doing poorly on grass, and the reasons have to do with the ability to convert feed (forages or fodder) and converting it into usable energy for growth, reproduction and lactation.

See, cattle are ruminant animals, meaning they have multiple-chambered stomachs that are typically designed for digesting coarse plant matter and converting that into usable energy and other nutrients, an attribute and physiological advantage that other animals like humans lack. (Of course these would be most non-ruminant animals excluding equines.) Their three esophageal fore-stomachs in addition to their one true stomach contain a large population of bacteria, fungi and protozoa that are more heavily concentrated the rumen. The rumen is the largest chamber that does the workhorse portion of breaking down plant matter.

The process where cows get their energy and protein from the plants they consume can be complicated, but when put more simply when cows eat they are not exactly feeding themselves, but rather the microflora living in them. These microflora break down the tough cellular walls of the plant material to get at the nutrients inside. These nutrients include energy, a little which is consumed by the microbes and the rest going to the cow as the plant material passes through the rest of the digestive tract. Typically cattle should consume enough energy to maintain or gain weight on pasture, but not all cattle are able to do so. You can get some cattle, like dairy cattle, that get into this "negative energy balance" where they are using more energy than they are consuming. This is where you can get some pretty thin cows, or cows that get so weak from so little energy that they become downers. And that is never a good thing to have.

So yes, cattle can become malnourished if they are strictly grass-fed, as much as I hate to tell you. The best thing you can do to prevent this is to make sure they are getting enough to eat, even if it means having to supplement with grain or a similar alternative source that is high in energy and protein. Molasses tubs work great, as well as salt-mineral blocks. Cotton-seed meal is a good energy source to consider too.

The Thing About Grain

Grain should not be seen as something to completely avoid for cattle because of some common misconceptions out there that grain makes cattle sick or kills them or whatever, and grass is best for them. Actually, grass can make cattle sick and kill them too! With grain, cattle will need grain if they are not getting enough energy from the roughage they are given, whether its hay or grass. Grain is good to assist growth in young cattle, and to help older animals maintain their weight.

Where the rubber meets the road in where grain is "bad" for cattle is when too much of it is fed over a long period of time, or too much is eaten too quickly. Grain cannot be fed as a 100% ration because it can certainly cause digestive issues in cattle that don't end in bloat or acidosis. As ruminant animals, cattle need roughage. If they don't get sufficient roughage, they can easily get quite ill and die. As a side note to this, cattle on feedlots are not given 100% grain. They are actually given less, around 80 to 90% grain, and the rest is roughage from silage or hay. Yes, even this kind of diet can (and has) caused issues particularly when it's done so over a prolonged period of around four months.

Over a long period of time a diet of around 80% grain can still cause chronic problems like sub-clinical acidosis. Sub-clinical acidosis is more difficult to detect than acute-acidosis, because it's a condition where the signs and symptoms are more subtle. Little things like not eating as long as other animals do, being a little slower than other cattle, sometimes kicking at the belly and others can be easily missed if a pen checker isn't looking for them. Acute acidosis, on the other hand, is more obvious. This is a condition that occurs when cattle gorge themselves on grain when they're first introduced to it, and then their acidity level in their rumens drops like a stone. Then these animals go completely off feed, become lethargic, and have foamy-grey diarrhea. Death can come quickly after if not caught and treated.

Death can also come quickly to those animals who bloat on eating too much grain too quickly. Bloat is where greasy bubbles accumulate in the rumen that cannot pop, and the methane gas that is usually released regularly through the mouth is trapped, resulting in the rumen expanding more and more like a balloon. The rumen can expand so much that it can cause asphyxiation (put so much pressure on the lungs that the animal cannot breathe) and thus death. You can tell if a cow has bloat by the unusual large "lump" that has formed on the left upper side. The only way to save the cow is to either poke a hole into the rumen wall with a trocar (surgically put a hole through the skin and the rumen wall, and a open-ended plug is screwed in to allow the continued release of gas to the outside), or to put a tube down the animal's esophagus and pour mineral oil down it. Both methods sound cruel, but would you rather stand by and allow the cow to suffer and eventually die, or do something quick to save it, even if the experience for the cow is not going to be a fun one? Hey, getting bloat isn't fun for a cow in and of itself!

As far as feeding grain is concerned, then, the logical means of feeding it is restricting intake. Feed only a few pounds a day and allow constant access to grass or hay. There's no need to feed a cow grain like those animals getting fattened in the feedlot, especially if all the grain she needs comes in one coffee-tin full per day!

If You Want Grass-fed Cattle, Manage, Manage, Manage!

If you really want to have grass-fed cattle, you have to manage everything from what they're getting on pasture, how they're being grazed to the supplements you may have to give. Know the plants growing in your pasture to know which are poisonous or which may produce toxins that could be fatal to your animals. Monitor your animals to see how they are doing, as far as whether they are doing well on pasture or may need to be supplemented. Have hay on hand during days or times it's not wise nor worth it to have them on pasture. And always have a block or feeder of salt and mineral mix for them, because cattle can never get sufficient nutrients and minerals from what they eat or what you feed them.

If you consider these things and more, then you won't have to worry about what is wrong with raising grass-fed cattle.
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