Toxicity of Leucaena leucocephala II. Reduced Fertility of Heifers Grazing Leucaena leucocephala.

Abstract

Twenty four heifers grazing Leucaena leucocephala cv. Peru were mated when they reached 300 kg live weight. Eight heifers conceived in less than four months, ten conceived in 9-18 months and six did not conceive in 12-27 months. Eleven similar heifers on grass pastures all conceived in less than two months. Growth rates of heifers with different reproductive performances were similar. Fourteen heifers were
slaughtered, including six which had not conceived, five which were not detectably pregnant by rectal palpation but had embryos one to six weeks old and three which had calved but not conceived again. All had some degree of goitre. All non-pregnant heifers had ovaries and uteri of normal appearance. All calves born had goitre. Five heifers tested pregnant failed to produce a calf. Three bulls used had normal semen and libido. A defect is suspected in establishment or maintenance of pregnancy after mating.