Preliminary study on the use of a Teladorsagia circumcincta bulk milk ELISA test in dairy goats under experimental conditions.

Abstract

An ELISA test for the detection of anti-Teladorsagia circumcincta antibodies in goat milk samples (both individual and bulk milk samples) has been developed in dairy goats experimentally infected with a trickle infection. The results observed were compared with those obtained when some other standard methods for the detection of animals infected with gastrointestinal nematodes (GIN), such as faecal egg counts (FEC) and serum pepsinogen levels. Some factors that could affect the final results of the test (dilution and nature of samples as well as their preservation at 4 degrees C for 0-10 days) were also monitored. The results show that the proposed test could allow the detection of infected herds using bulk milk samples. The levels of anti-T. circumcincta antibodies in milk and serum samples and the concentrations of serum pepsinogen showed a similar pattern over time. Refrigeration of milk samples for less than 5 days or its preservation with potassium dichromate for 10 days did not significantly affect the ability of the test to detect infected animals. Finally, when a commercial Ostertagia ostertagi ELISA kit was used to assay milk samples from goats infected with T. circumcincta, the results suggest that it may be possible to use a crude O. ostertagi antigen-based ELISA for the detection of goats infected with T. circumcincta.