Clenbuterol (planipart™) for the postponement of parturition in cattle
ABSTRACT Clenbuterol is a highly specific, long-acting (four to eight hours) beta-two sympathomimetic which causes bronchodilation and tocolysis (myometrial paralysis). The tocolytic effect was explored as a means to control parturition and reduce dystocia. Forty-six heifers were injected i.m. with either Clenbuterol or saline placebo in a randomly controlled experiment. Animals were treated when a cervical dilation of five centimeters or more was detected by vaginal examination. Length of first, second and third stages of parturition, ease of parturition, maternal pelvic area and calf viability were compared between treatment groups. Treatment with Clenbuterol increased (P<0.025; 119 vs 468 mins) the time heifers were in Stage I. However, the lengths of Stages II and III, pelvic area at birth and calf viability were not influenced by treatment. Diameter of the cervix at treatment was negatively related to the length of Stage I delay. Pelvic area also significantly affected the length of Stage II. Clenbuterol effectively delays Stage I of parturition with no adverse effects on the fetus or dam.
Journal of Equine Veterinary Science 01/2014; 34(1):211. DOI:10.1016/j.jevs.2013.10.153 · 0.87 Impact Factor
- "In humans, this is mimicked by the administration of b 2 -adrenergic stimulants to postpone parturition and treat preterm labor  . In cattle, the b 2 adrenergic drug, clenbuterol is used to facilitate obstetrical manipulations . Although such clinical use is uncommon in mares, clenbuterol decreases uterine tone at all stages of equine pregnancy . "
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ABSTRACT: Clenbuterol, as other sympathomimetic drugs, relaxes the myometrium, thus causing a short-term inhibition of labor and the delay of parturition. This study has examined the influence of clenbuterol on the release of prostaglandin F2 alpha (PGF2 alpha) induced by oxytocin alone or with estradiol-17 beta. Five bilaterally ovariectomized heifers, primed with progesterone for 14 days, were used in two experiments. In the first they received two i.v. injections of oxytocin 6h apart, with and without an i.v. injection of clenbuterol before the second oxytocin injection; the second experiment was similar to the first except that the animals were given estradiol-17 beta 30 min after the first oxytocin injection. Frequent blood samples were taken for the measurement of 13,14-dihydro-15-keto-PGF2 alpha by radioimmunoassay. The data show that clenbuterol does not influence PGF2 alpha release in response to oxytocin alone or with estradiol-17 beta, and it does not inhibit the basal release of PGF2 alpha. This suggests that clenbuterol does not act on the endometrium to alter the secretion of PGF2 alpha in the non-pregnant cow.Prostaglandins 03/1988; 35(2):163-71. DOI:10.1016/0090-6980(88)90084-6
- Journal of Veterinary Pharmacology and Therapeutics 04/1988; 11(1):109-11. DOI:10.1111/j.1365-2885.1988.tb00127.x · 1.19 Impact Factor