ABORTIFACIENT EFFECTS OF LODGEPOLE PINE (PINUS-CONTORTA) AND COMMON JUNIPER (JUNIPERUS-COMMUNIS) ON CATTLE

Lodgepole pine (Pinus contorts) and common juniper (Juniperus communis ) contain high levels of isocupressic acid that has been identified as the abortifacient component of ponderosa pine needles in cattle. Ther efore, the abortifacient potential of P contorta and J communis needle s was tested In feeding trials with pregnant cattle. Cows(2 groups of 2 each) were fed by gavage 4.5-5.5 kg/d ground dry needles from either P contorta or J communis starting on gestation day 250. Isocupressic acid (ICA) levels in P contorta needles and J communis plant material were 0.8 and 2.0% (dry weight) respectively. Cows fed P contorta recei ved a daily dose of 62-78 mg ICA/kg body weight and aborted after 8 an d 10 d. The 2 cows fed J communis received a daily dose of 190 and 245 mg ICA/kg body weight and aborted after 3 and 4 days respectively. Al l cows retained fetal membranes and had classical clinical signs of pi ne needle-induced abortion. Pinus ponderosa, P contorta, J communis, a nd Cupressus macrocarpa samples were also analyzed for the presence of myristate and laurate esters of 1,14-tetradecanediol and 1,12-dodecan ediol. These lipid like compounds of P ponderosa have potent vasoconst rictive activity in a placentome perfusion assay and are proposed as p ossible abortifacients in cattle. Concentration of the vasoactive lipi ds were 0.028% (P ponderosa), 0.023% (P contorta), 0.001% (J communis) , and none detected (C macrocarpa). It was concluded that these compou nds are not required for the plant material to be abortifacient In cat tle.