43- Annual Screening of gastrointestinal nematodes in a dairy farm in Buenos Aires Province: correlation with milk production.

PERRI, AF; LICOFF, N; LAZARO, L; FORMÍA, N.; FERNÁNDEZ-FRANCIA, G.; MIGLIERINA, M; FERNÁNDEZ-IGARTÚA, MB; MEJIA, ME; BECÚ-VILLALOBOS,D.; LACAU-MENGIDO, I.M.

Buenos Aires, Argentina

Congreso; X Jornadas de la Sociedad Argentina de Biologí; 2008

Sociedad Argentina de Bilogía

Gastrointestinal parasitism is a major constraint in grazing livestock production systems. An intensive parasitologic screening was conducted to evaluate the parasitic degree of infestation of the dairy farm of Inchausti (UNLP, 25 de Mayo. Bs.As) and to estimate its effect on milk production. During one year (Mar 2007 - Feb 2008) grass forage samples were taken every fortnight from every paddock where each herd grazed (10 herds, 24 samples) to obtain, identify and count infesting larvae. Individual fecal samples were taken monthly from every animal in the farm, to quantify nematode eggs per gram of feces (EPG). Individual daily milk production was registered. Larvae belonged to Cooperia, Ostertagia, Haemonchus and Trichostrongylus geni in this order of prevalence. EPG was higher in the calves from the second and third rearing categories. In the adult cows, EPG was ten fold lower than in calves. EPG did not correlate with milk production but lactating curves from animals with positive EPG counting in the first postpartum sample had a shorter period of maximal production than cows with EPG=0. We conclude that in this dairy farm there is a high offer of nematode parasites with infestation in all the rearing and producing categories of animals, and that this event affects milk production.