Summary of “Fecal Worm Egg Count Reduction”
Trials in Merck Animal Health National Data Base
• Donald H. Bliss1
• Robert D. Moore2
• William G. Kvasnicka3
•
•
1MidAmerica
Ag Research, Verona, WI
2College of Agriculture, Biotechnology & Natural
Resources, University of Nevada
• 3University of Nevada, Professor Emeritus
Protocol for Fecal Worm Egg
Count Reduction Test (FECRT)
 All clinics agreed to use a standard protocol:
– 20 samples taken at the time of treatment.
– 20 samples taken 14-days after treatment.
– Pre-/post-treatment samples sent to same lab:
 ● Treatment not revealed until test completed.
 ● Modified WI Sugar Flotation Technique (Eggs/3 g).
 ● Results sent to participating clinic and entered

in Merck Animal Health National Database.
Fecal Egg Count Reduction
Test Results
 250+ Participating Vet Clinics.
 24+ States Represented.
 580+ Trials Completed.
 19,996 Samples Analyzed.
– 10,069 Pre-treatment Samples.
– 9,927 Post-treatment Samples.
Table 1: Efficacy Summary for Fecal Egg Count Reduction
Test Conducted with Macocyclic Lactone Endecticide PourOn Products (2009-2013).
_________________________________________________________________
Products
No. of
Trials
Pour-ons:
Ivomec® PO
Ivermectin PO
Dectomax® PO
Cydectin® PO
Eprinex® PO
3
26
10
11
3
No. of
Samples
108
1,164
431
477
144
Egg Counts/3g*
Percent
Pre-Rx
Post-Rx Efficacy(%)
59.1
71.5
46.8
58.3
49.3
43.2
38.7
16.4
16.0
38.0
27.0%
45.8%
65.1%
72.5%
22.9%
--------------------------------------------------------------------------------PO Summary
53
2,324
62.1
30.0
51.6%
_________________________________________________________________
*All samples taken at Rx and again 14-days post-Rx.
**Updated Jan. 3, 2013
Table 2: Efficacy Summary for Fecal Egg Count Reduction
Test Conducted with Injectable Macrocylic Lactone
Endecticide Products (2009-2013).
__________________________________________________________________________________
No. of
Trials
No. of
Egg Counts/3g*
Samples Pre-Rx
Post-Rx
Percent
Efficacy
Products
Injections:
Ivomec® Inj.
15
984
66.5
36.8
44.6%
Ivomec® Plus
10
413
97.4
51.7
46.9%
Dectomax® Inj. 23
966
63.1
16.0
74.6%
Cydectin Inj.
7
311
35.0
6.0
82.8%
Ivermectin Inj.
10
506
90.7
55.0
39.4%
Generic Ivo Plus 4
149
92.9
46.7
49.8%
-----------------------------------------------------------------------------------------Inj. Summary:
69
3,329
71.7
32.1
55.2%
_____________________________________________________________
*All samples taken at Rx and again 14-days post-Rx.
**Updated Jan. 3, 2013
Table 3: Efficacy Summary for Fecal Egg Count Reduction
Test Conducted with Various Safe-Guard® & Panacur®
Formulations.
______________________________________________________________________________________
Products
No of
Trials
No of
Samples
Egg Counts/3g*
Pre-Rx
Post-Rx
Percent
Efficacy
Panacur® Drench
32
1,296
59.3
0.7
98.8%
SG Drench/Paste
71
2,979
65.0
0.8
98.7%
Summary-Drench
103
4,275
63.2
0.8
98.7%
-----------------------------------------------------------------------------------SG Feed/1.96%
28
1,449
45.6
0.2
99.5%
SG Mineral
7
265
36.4
1.6
95.5%
Liquid Feed
10
388
42.3
1.4
96.6%
Cubes/blocks/Paste 10
447
33.7
2.0
94.0%
-----------------------------------------------------------------------------------Overall Summary** 158
6,824
55.7
0.8
98.5%
________________________________________________________________
* All samples taken at Rx and again 14-days post-Rx – Updated Jan. 3, 2013.
** Note: Coccidia prevalence was reduced by 56.5%.
Table 4:
Efficacy Summary for Fecal Egg Count
Reduction Test Conducted with Safe-Guard®/ Panacur® in
Combination with Various Endecticide Formulations.
_____________________________________________________________________________________
Combination
No of
No of
Egg Counts/3g
Percent
Product
Trials
Samples Pre-Rx Post-Rx
Efficacy
------------------------------------------------------------------------------------------------------Safe-Guard® or Panacur ® plus:
Ivomec® Inj./plus/PO 19
917
77.2
0.4
99.4%
Ivermectin PO/Inj.
28
1,155
76.7
0.4
99.4%
Dectomax® Inj./PO
6
223
83.4
0.1
99.8%
Cydectin PO
1
41
134.0
0.1
99.9%
Combination
Summary
---------------------------------------------------------------------54
2,366
78.7
0.4
99.4%
_______________________________________________________
Note: Coccidia prevalence was reduced by 76.9%
*Updated Jan. 3, 2013
Table 5: Efficacy Summary for Fecal Egg Count Reduction
Test Conducted for all Products.
______________________________________________________________________________________
Number of
Products
Trials
Endecticide
Injectable:
Pour-On:
Safe-Guard®
/Panacur®
Combination
Treatment***
Number of
Samples
Egg Counts/3g** Percent
Pre-Rx Post-Rx Efficacy(%)
69
53
3,329
2,324
71.7
62.1
32.1
30.0
55.2%
51.6%
158
6,824
55.7
0.8
98.5%
54
2,336
78.7
0.4
99.4%
______________________________________________________________________
*Updated Jan. 3, 2013, **All samples taken at Rx and 14-days post-Rx.
*** Safe-Guard® plus an Endecticide.
Table 6: Comparison of FECRT Efficacy
for ML Pour-Ons 2008(AABP) vs. 2013(Jan. 3)
Products
No. of Trials Percent No. of Trials Percent Efficacy
2008
Efficacy 2009-2013 Efficacy Change
---------------------------------------------------------------------------------------------------------
Ivomec®
Ivermectin
Dectomax®
Cydectin®
Summary
8
72.3%
3
27.0%
- 45.3%
35
59.7%
26
45.8%
- 23.9%
8
78.9%
10
65.1%
- 13.8%
9
67.2%
11
72.5%
+ 5.3%
----------------------------------------------------------------------------
60
Updated Jan. 3, 2013
66.1%
53
51.2%
- 14.9%
Table 7: Comparison of FECRT Efficacy ML
Injectables: 2008(AABP) vs. 2013(Jan. 3)
Products
No. of Trials Percent No. of Trials Percent Efficacy
2008
Efficacy 2009-2013 Efficacy Change
----------------------------------------------------------------------------------------------Ivomec® Inj.
6
76.2%
15
44.6%
- 31.6%
Ivomec® Plus
6
42.6%
10
46.9%
+ 4.3%
Ivermectin or
Ivermectin plus 1
50.0%
14
41.4%
- 8.6%
Dectomax®
11
90.5%
23
74.6%
- 15.9%
Cydectin®
2
98.1%
7
82.8%
-15.3%
---------------------------------------------------------------------------Summary
26
72.5%
69
55.2% -17.3%
Updated January 3, 2013