[Therapy of hypodermyiasis in heifers from the economic point of view].

The test set of animals consisted of sixty one- to two-year-old heifers of the Slovak Spotted and Pinzgau breeds kept at three sites. The Hypocid preparation (containing 40% trichlorphon) in the dose of 15 ml per 100 kg of live weight was applied to these cows by the lavage method in the sacrolumbar region of the spine in 1973. Another group, consisting of 58 heifers, was left untreated as controls. In the experimental period extending over 158, 150 and 120 days at different sites (143 days on an average), weight gains and the health condition of the experimental and control animals were checked in monthly intervals. The average extensity of invasion in the control heifers was 79.31% and the intensity of invasion was 14.58%. The extenseffectiveness of Hypocid (EE) was 97.90% and the intenseffectiveness of the preparation (IE) was 99.99%. The results prove a negative effect of hypodermatosis on the weight gains of untreated heifers and high profitability of the therapy: after subtraction of the costs of therapy the savings were 1.74, 3.88 and 2.25 crowns per kg gain per day (2.62 crowns on an average). The veterinary measures gave the following savings per each crown expended: 2,243.55; 3,066.85 and 922.83 crowns (depending on site).