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Newsletter of Penn Dutch Cow Care April 2008

Hi Folks,

            With the pasture season just beginning, I thought I would take some time to consider the issue of parasites – various prevention strategies as well as potential treatments. Parasites come either as internal or external. Internal parasites include stomach worms and coccidia. External parasites include flies and mange/lice. By the way, ringworm is not a parasite but a fungus that grows on the outermost layer of skin. Since mange and lice occur mainly in winter and we are quickly leaving that behind, we’ll concentrate on the others.

            Essentially parasites take advantage of the fact that animals on farms are enclosed and cannot get away, either by a perimeter fence or by stalls indoors. Free roaming cattle in the original prairie probably had a low level of parasitism with which they could live in balance. Parasites generally thrive with (1) high animal density, (2) animals kept in same areas continuously, (3) nutritionally deprived animals and (4) poor pasture & poor premises management. Flies also take advantage of animals always being in the same areas, just as the internal parasites do. Coccidia usually are found in animals while they are indoors in pens that are being continually used. Coccidia problems are not usually seen when animals are on pasture. On the other hand, stomach worms are usually found in animals on pasture, especially at peak and late season when the parasite population has multiplied many times. This is due to cattle re-infecting the pastures in the warm, humid months with fresh manure carrying worm eggs ready to hatch and be eaten again with pasture grass. That is why it is critical to never have young stock follow older stock – young stock immune systems are not capable of withstanding parasitism like mature adult cattle can. (Johnes can also be passed to younger animals following older animals on pasture.) In fact, it is very rare that adult cows need any kind of wormer at all, unless you want to increase milk production a few pounds per day. Adult cows do not become infested – check some manure samples and you’ll see. However, young stock can get hammered by parasites way too often. Yet a very low level of parasites would probably create a stronger animal than an animal which is routinely de-wormed – only by checking manure samples can the level of infection be known.

            Also, contributing to parasitism is the harmful practice of not feeding hay to pre-weaned calves. Why is this harmful? In the search to satisfy their instinctual need for fiber, they will eat bedding which will likely have parasites on it. Just watch some calves for a while that do not get any hay fed to them – they will nibble the ground for fibrous material – guaranteed. Additionally, the developing rumen (which causes the instinct to want fiber) is not just a “sponge” that absorbs and passes on volatile fatty acids (supplied most quickly by grain) – it is also a muscular organ which turns over every minute or two. The muscles become developed more strongly with hay in the diet. Ever see bloating calves? What is their diet usually?

            In any case, a multi-prong approach is needed to prevent a build-up for parasites and to help animals cope with the seasonal parasites that livestock farms usually experience. A multi-prong approach is logical since (1) a variety of approaches for any problem will give a better chance of success, (2) if one pillar of the multi-prong approach isn’t working, the other factors are still in place, (3) natural treatments can work better and, perhaps most importantly, (4) there will be less chance of resistance developing.

            Post-weaning disasters of youngstock can be best avoided by weaning very strong, big calves and keep feeding them well when they are sent to the back pasture and providing shelter from the elements. If crummy pasture conditions exist, it is likely that a string of cool, damp days may bring on coughing and pneumonia; or if there is rank, stalky pasture, the calves/yearlings will poke their eyes while they go for the lush green growth down low – causing tearing and flies to come to the eyes and eventual pinkeye. The main culprit is usually due to internal parasites dragging down the immune system of the animals and leaving them relatively defenseless.

            By planting high tannin plants, animals may successfully browse these and help their gut remain stronger to infestation pressures. Animals grazing on chicory and birdsfoot trefoil sown into white clover and ryegrass pastures have been shown to have reduced worm egg counts compared to animals grazed on straight white clover and ryegrass. A mix by Fertrell (717-367-1566) was shown at Clemson University to reduce fecal egg counts in heifers grazed on the same pasture as compared to heifers not treated with the mix (cayenne, garlic, diatomaceous earth). By giving young calves a garlic based product, onset of diarrhea was delayed. If it can be delayed, maybe it won’t occur. NeemaTox by AgriDynamics (610-250-9280) has been giving good results to many farmers in various regions as well. These treatments, whether by the animals eating the plants or the plant medicines being given orally, are natural and OK for organics.

            Flies are best reduced by keeping premises and animals dry: manure (less the 40% moisture), animals (liberally dust lime stone powder on their backs – not a tiny sprinkle) and tunnel ventilation when inside the barn. Fly traps with pheromones and sticky tapes for actual killing of flies work well. Predator wasps, if wisely placed in certain areas of the barn and surrounding areas will reduce the fly maggots. Then and only then will the natural botanical fly sprays allowed for organics work best (EctoPhyte by AgriDynamics and NoFly by Crystal Creek, both available from Lancaster Ag Products 717-295-9100).

            To really keep both flies and internal parasites down in the pasture, follow the cattle with chickens and/or hogs on the pastures. They will level out those manure paddies as well as eat fresh green plants from the pasture to give you wonderful pasture raised poultry, eggs and pork.

He causes the grass to grow for the cattle, and vegetation for the service of man, that he may bring forth food from the earth. 

Psalm 104:14 KJ

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