Monday, July 20, 2015

Fecal Egg Count Reduction

On  July 9, fecal egg counts ranged from 0 to 4675 epg and averaged 318 + 759 epg.  The large standard deviation indicates that there was a wide fluctuation in egg counts. The median egg count was only 38 epg.

The efficacy of an anthelmintic treatment can be determined by comparing before and after fecal egg counts. The period between sampling varies by anthelmintic, but is usually two weeks when more than one drug is being evaluated.

Fecal samples are collected from every buck every two weeks.

Only goats with initial fecal egg counts of  > 300 epg were included in calculations. In addition, some goats did not have samples on one or both of the dates, so a reduction could not be calculated.  Fecal egg count reductions were calculated for 66 goats in the test. Among those goats, the percent reduction varied from 0 to 100.

Fecal egg counts increased in five of the 68 goats. If the data from these 5 goats is removed from the dataset (it would skew the average), FECR varied from 30 to 100 percent and averaged 92 + 13 percent. The median FECR was 98%.  A effective treatment should reduce fecal egg counts by 95 percent or more.

Fecal egg count reduction (FECR) varied considerable among consignments.  The sequential dosing was very effective in some consignments and less effective in others. Negative numbers indicate that the fecal egg count went up after the sequential dosing.

If this was the case with several goats in a consignment, the consignor's farm may have resistance to all three anthelmintic classes. It is recommended that these consignors test for anthelmintic resistance in their herds by having more fecal egg counts done or by submitting a pooled manure sample for DrenchRite analysis.

Download Fecal Egg Count Reduction Report (July 9)