Variação estacional na contagem de ovos por grama de fezes de equídeos e sua expressão em ovos por grama de matéria fecal dessecada

Abstract

The variable EPG (eggs per gram of faeces) has been much used as a parameter to estimate animal worm burdens. This parameter, periodically determined, may indicate the most adequate moments for sample collections for that and for other objectives. The season of the year has a relevant effect on environmental factors, so the A.A. tried to assess their global interference upon EPG in twelve equidae kept in one pasture exclusively grassed with Pannicum maximum in the “CIZIP Experimental Station”, in Pirassununga, State of Sao Paulo. Four of these animals were Equus asinus and eight of them were E. caballus and of the last four belonged to a light breed, “Mangalarga”, and four to a heavy breed, “Postier-Breton”. They were grazed together during one year, and every month three samples of faeces, on three consecutive days, were collected from each of them. The egg counts were made through the Mc Master technique and were expressed both in terms of fresch and dried faeces, as determined by the AOAC method. The results are condensed in Tab. 1 to 3 and in Graph. 1 to 6, and they show higher EPG counts on the months with higher rainfall. This tendency was observed both for results expressed in terms of fresh and dried faeces, but the last ones seemed to offer a neater and more conspicuous expression of the influence of the season of the year on the evolution of EPG values. Such influence appeared consistently for the two species of equidae and for the two breeds of equinae.