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THE MOO NEWS

Newsletter of Penn Dutch Cow Care May 2012

Hi Folks,

As spring happens, life unfolds in its many forms. And with plants this is especially true. While it hasn’t been terribly warm in the northeast, everything is green at this point and growing. Crops are being planted and harvested already. These are the crops that we intend to feed to the cattle as their primary source of nutrition for the time of year when green plants are no longer growing. But during the mid-spring through early-autumn we should be thinking of pasture as the main feed. Why? For one, it is a cheap feed. But probably more importantly it provides a diverse diet which the cows appreciate – wouldn’t you?

Pasture is cheap feed because it is harvested by the cows themselves. They also fertilize the land. Matching what is standing there to what you desire your cows to take in from it will often result in spare acreage for you to mechanically harvest feed for later use - less purchased feed! I went over this last month, here it is a nut shell: dry matter desired for the cows divided by what is standing there = square footage needed. Even if sizing paddocks for 100% dry matter intake from pasture (like for growing heifers) I find most groups of animals are way too much area. That wasted area could become hay or baleage!

Pasture is the healthiest feed because of the bovine digestive enzymes present in the gut and it makes the cows exercise and move around to harvest it.

Probably the best aspect to pasturing cows is that they can pick and choose from among a variety of live, growing plants – rather than only consume a constant supply of stored, fermented feeds. The variety of plants that they will consume no doubt includes what people commonly call “weeds”. Yet I am no longer sure what the definition of a weed really is. The conventional definition is a plant growing where we don’t want it to. But if animals eat it, then couldn’t such a plant be considered a feed source? And what if the plant that is readily eaten also contains nutrients that rival or exceed those found in alfalfa, ryegrass or clover? Then the “weed” might even be considered beneficial to their overall diet, providing both essential nutrients in addition to possible medicinal components.

While not many projects are funded to study the nutritional content of “weeds” for herbivores like cows, sheep, goats and horses, there are some available.

In a 2006 study, pasture “weeds” analyzed on New Zealand’s Massey University organic and conventional dairy farms showed most “weeds” being the same or better feed quality (in terms of ADF) and higher macro- and micro-nutrients than their perennial ryegrass and white clover stands. In terms of macro and micro nutrients: chicory had significantly higher levels of P, S, Mg, Na, Cu, Zn, B; narrow leaf plantain had higher levels of P, S, Ca, Na, Cu, Zn, Co; and dandelion had significantly higher amounts of P, Mg, Na, Cu, Zn, B.

In a study done by Jerry Brunetti (see www.agri-dynamics.com), common “weeds” were compared to alfalfa. In terms of macro- and micro-nutrients: nettle leaf showed better results than alfalfa in 13 measurements: protein, N:S, ADF, TDN, NEL, Ca, P, K, S, Fe, Zn, Mn, and B;  dandelion was better in 12 measurements, comfrey in 10, with chicory and plantain better in 8 measurements compared to alfalfa.

In an old study from 1933 done in Oklahoma, all the “weeds” were higher in N, P and Ca than the native grasses and they found that young plants are higher in mineral nutrients and nitrogen than older plants. Their overall conclusion is that “the presence of these weeds in the hay would increase the total mineral content of the forage and under many conditions this effect would improve rather than injure its feeding value.”

Secondary plant metabolites in fresh plants (pasture) can provide medicinal qualities and animals instinctively search out plants that are high in condensed tannins which help repel internal worms. Plants high in condensed tannins include the chicory mentioned above. Then there are the non-bloating legumes with high tannins such as birdsfoot trefoil, lespedeza, and sanfoin. All have shown in live animal studies (not test tubes) to decrease internal worm burdens that are so common in weaned groups of heifers placed on the same pasture year after year – areas where parasites are just waiting for them time and time again.

I have observed that cows, heifers and steers will readily eat true forages and weeds - if they are in a young stage of life. Once a plant starts going to seed, most animals won’t eat them unless forced to (by starvation or simply nothing else to eat). From the old Oklahoma study that concluded young plants have more nutrients and the New Zealand and Jerry Brunetti’s study that showed which and how much of each nutrient is present, it is reasonable to state that having a true variety of plants in the pasture is quite beneficial for cattle.

Do keep in mind, however, that there do exist truly toxic plants. These include bracken fern, wild cherry leaves that are wilted, ergot growing in small grains during cool damp weather, horsetail, horse chestnut, false hellebore, jimpson weed (thorn apple), mountain laurel, common milkweed, horse nettle, deadly nightshade, wilted red maple leaves, pokeweed, oak acorns, white snake root, water hemlock, and the garden yew bush. Unless starving, herbivores normally avoid such plants. If seen these plants really should be removed.

In pastures that are un-even in growth with normal plants (forages and common “weeds”) that might have plants older than others, consider pre-clippping a field and letting the plants wilt. This will make everything more palatable to the animals and also reduce the bloat potential of legumes. Pre-clip about 4 hours before grazing. Do not pre-clip pastures with the previously mentioned toxic plants!

While you’re out moving up fence, see what the cows have eaten in the last paddock. It’ll most likely surprise you. It’s fun to watch herbivores eating out on pasture and along the margins of laneways - and by their sleek hair coat, good muscle definition and health stripes, you’ll know that you are treating them well.

 

For Bovinity Health, information on functional alternatives to antibiotics see:
www.bovinityhealth.com

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