Tuesday, October 20, 2015

Final Fecal Egg Counts Skyrocket

For the fecal samples collected on October 1, the last day of the test, fecal egg counts ranged from 475 to 59,350 epg and averaged 6,043 + 7,843 epg. The large standard deviation (STDEV) is indicative of a very wide fluctuation in egg counts.

If the extremely high egg count of 59,350 epg is removed from the data set, the average FEC is reduced to 5360 + 4994 epg. This is still extremely high, as is the lower median egg count of 3,675 epg. 2000 epg is usually considered to be of clinical significance for the barber pole worm.

Fecal samples could not be obtained from three goats. Multiple attempts are made to get a fecal sample from a goat.  One fecal egg count could not be determined due to a processing error.

Despite the high fecal egg counts, FAMACHA© scores improved during the final two weeks of the test (9/17-10/1) and only four goats were dewormed. On October 1, no goats had FAMACHA© scores higher than 3.

While increasing egg counts might have been expected at the end of the test, the substantially higher egg counts were not, especially given the lack of clinical parasitism (anemia). The supplemental feeding (of soy hulls) most likely improved parasite resilience, while having no effect on resistance. Resilience is tolerance of infection, whereas resistance is level of infection. Both traits are important.

Two to 4 grams of feces are used to determine an individual fecal egg count. After weighing the fecal sample and mixing it with a specific amount of flotation solution, all of the eggs in the two chambers of the McMaster slide are counted (manually). The number of eggs is multiplied by a factor of 25 to 50, depending upon the amount of feces (2-4 g) and flotation solution (26-28 ml). For most of the goats, a sample size of 4 g is utilized. Sometimes, 4 g of feces cannot be obtained.

Download October 1 fecal egg count report

Note:  if there is a line through the fecal egg count data (strike-through), the goat was dewormed two weeks prior to the measurement, and the data does not count towards selection of the top 10 bucks.