THE EFFECT OF THE DESPARASITATION FREQUENCY OVER THE WEIGHT GAIN, PARASITICAL LOAD AND HEMATIC VALUES IN DAIRY CALVES.

Abstract

Several frequencies of internal desparasitation in dairy calves were compared. For that, 20 calf heads, cross Holstein with Zebu, of both sex were used, with average weight of 60.6 kg PV choosing at random five animals at four frequencies of desparasitation. 45, 90, 180 days, and the witness, respectively. It was used Levamisol 7.5% with dose of 1 cc per 15 kg PV by subcutaneous. Each group was separately controlled in four plots of D. swazilandensis with rotation of seven days of rising per 21 days of resting. During the dry season were fed with 1.5 kg/animal/day, of a mixture of molasses, 12% of fish flour and mineralized salt. The data were analysed with a random design, with trials of comparison of averages. It was found a gain of the total weight of 59.7, 47.8, 41.7 and 22.9 kg/animal to the frecuencies of desparasitation each 45, 90, 180 days, and the witness, respectively; while the gains of daily weight were of 325.8, 264.6, 230.0 and 126.5 g, respectively. There were differences (P<0.05) between the frequency of 45 days and the other frequencies of desparasitation. The monthly parasitical load was generally low (<40 HPGH) during the frequency of 45 days, whereas in the rest of the grups the level of HPGH was high (>500 HPGH), except during the months of April and May to the group desparasited each 90 days. Also, it was observed an increment in some hematologic parameters (hemoglobin and hematrocrits) in proportion as was reduced the interval of desparasitation. It is concluded under the conditions of this study that the frequency of desparasitation each 45 days offers the best behavior to the control of the internal parasitism in dairy calves.