What is the first line of defense when parasites attack livestock? A drug (chemical) is immediately purchased and applied to the animal. Does it work? Yes, it usually does. For how long? Days, weeks, months, rarely more than one year and then the predators return. Or does the chemical become ineffective after several years of use? What now? A newly developed chemical and the same process again takes place. Parasites have and will, continue to develop resistance to man made chemicals. How do we end this?
In 2002 I found notice of a research program at the USDA Agricultural Research Center (ARC) at Beltsville, Maryland to use the host immune system of cattle to reduce GI nematodes (stomach worms).
The following are passages from a paper on the ARC site listing research results.
―Early results demonstrated the bovine immune system effective in reducing the number of parasites established in the host. One exception was Ostertagia ostertagi, but even with this species, the immune system reduced transmission by reducing egg count.
―These studies indicate that it is feasible to control nematode infections by using the host immune system. Recently we have proven that host genetics plays an important role in determining if individual cattle become immune or not.
―Although the anthelmintics currently used to control the parasites are efficacious and safe, there are increasing concerns that within a very short time period such control programs will be inadequate.
―Resistance to the drugs by parasites infecting ruminants is increasing worldwide, changing the current perception that the economic effects of the parasites are normal expenses of the livestock raising system.
―The only feasible and economically viable alternative to heavy anthelmintic usage is to use the host immune system and the diversity of the host genome to control disease severity and transmission.
―Resistance to gastrointestinal nematodes is strongly influenced by host genetics and a few genetically susceptible animals are responsible for most parasite transmission.
―Within the past year over 400 immune related genes in have been identified.
―As important genes are identified, this information will allow the culling of animals highly susceptible to parasite infection, reduce the numbers of parasite eggs on pasture resulting in a concomitant reduction in anthelmintic use.
―Internal parasites interfere with nutrient digestion and absorption and decreased growth and productivity of grazing cattle. Parasites can also reduce resistance to other infectious agents, and the effectiveness of vaccinations.
To date, there are no commercial entities pursuing testing for resistant genes so it is up to the individual producer to step up and implement a plan of his design. It does not require a PhD, so there is no reason to put it off. Following nature’s layout is all that is needed.
All over the country cattle and sheep producers are putting genetics back to work instead of depending on a chemical. The process can be done cold turkey by discontinuing all chemicals and selling the failures or by giving a young animal one dose and none thereafter until you decide to quit altogether. Once begun, stick to the program, do not falter. Continuing the process year after year stacks the genetics deeper into the animal’s background (pedigree) which makes the resistance stronger. If possible, buy bulls from seed stock producers also breeding for parasite resistance and that will boost the efficacy by adding the sires positive genetics to the dams genes. The complete eradication of any parasite is not the goal. A few must remain to enable the animal to maintain resistance to the offender. Eliminating chemicals and controlling parasites naturally are the first steps to a healthy, productive herd or flock and profitability.
Nature’s method is long lasting and time tested.