A HERDSMAN'S HANDBOOK FOR THE MODERN HOMESTEADER

Enlarge Image Image Gallery

Article Tools

Image Gallery

Print

E-mail

Comments

RSS

Beginning farmers usually do pretty well with gardens, chopping wood and building outhouses . . . but the birth of that first calf or litter of pigs generally sets 'em back a couple of notches. R.J. Holliday DVM, a veterinarian in Missouri and MOTHER contributor, intends to remedy the situation. His tool? A new handbook precisely designed to explain all the animal facts of life in language that new back-to-the-landers can understand.

MOTHER is serializing the manual as Dr. Holliday completes each chapter and here's installment No. 5.

» COMMON SENSE CONTROL OF INTERNAL PARASITES IN RUMINANTS

No discussion of ruminant nutrition and management is complete without devoting some time to an understanding of the role played by internal parasites in disease conditions and in efficient production.

Cattle, sheep, and goats the world over support many kinds of internal parasites. Some of these hangers-on have no apparent ill effects on their hosts and seem only to be "along for the ride", while others cause such drastic symptoms that they make profitable production of livestock almost impossible the areas where they occur.

The damage done by these creatures is threefold:

First, and most obvious, heavily parasitized animals do not enjoy good health and they do not "do" as well as animals that harbor only a few worms. Young animals that are severely affected are often permanently stunted and never realize their full potential for size and productivity.

Second, it's expensive in both dollars and time to buy and to administer the drugs commonly used to deworm animals.

Third, and finally, a few of these parasites occasionally infect humans, which puts the necessity for some form of control on a more personal basis.

» RUMINANT PARASITES IN THE U.S.

In this country the commonly found ruminant internal parasites fall into three classes: I 1I Nematodes or roundworms, 121 Cestodes or tapeworms and 131 Trematodes, otherwise known as flatworms or flukes.

» ROUND WORMS

There are several species of roundworms worthy of consideration. Haemonchus contortus, Ostertagia ostertagi and Trichostrongylus axei are found in the stomach. The intestines are inhabited by varieties of the genus Cooperia, the ruminant hookworm called Bunostomum phlebotomum and the nodular worms (0esoghagostomum radiatum). All these worms have similar life cycles, even though they vary in size from almost microscopic to about 1-1/4 inches long.

Mature roundworms live in the digestive tract, and the eggs produced there are eventually passed in the host animal's droppings. Warm, humid weather favors their development and, under proper conditions, the eggs soon hatch into larvae that are able to infect a new host within two to six days.

The infective roundworm larvae are able to migrate a short way up the blades of grass, and there they lie in wait until they either perish or some unfortunate beast comes along and them into its mouth with the desired forage. Some of the more daring species of immature roundworms can even burr, through a host animal's intact skin to gain entrance to body. The larvae continue to develop after this entry and, in three to four weeks, become adults in the gut of the new host. At this time they begin egg production and the life cycle is reestablished.

RSS | Comments | E-mail | Print