Pregnancy in goats does not influence intake of novel or familiar foods with or without toxins

Abstract

Some hypothesize that mammals decrease intake of foods that contain toxins during pregnancy to protect the fetus. We conducted a longitudinal study of feeding behavior to determine if pregnancy-related changes in food selection and intake occurred in goats. Goats eat modest amounts of toxic plants, some of which contain teratogenic or abortifacient compounds, but it is not known if pregnant and non-pregnant goats differ in food selection. The embryo is susceptible to toxins during all stages of pregnancy, but especially so during organogenesis early in pregnancy. Thus, we hypothesized that food selection and intake by pregnant versus non-pregnant goats may differ during various stages of pregnancy. We examined the following predictions that stem from this hypothesis: relative to non-pregnant goats, pregnant goats may alter selection of familiar foods that contain toxins, and of familiar and unfamiliar foods that do not contain toxins. We fed 14 plants with known or probable teratogenic properties during two pregnancies. We also offered beet pulp containing 0.5% LiCl during one pregnancy to test for increased sensitivity to toxins. In addition, we offered novel foods several times during one pregnancy to test for increased food neophobia or neophyllia. Finally, we measured intake of the basal ration by pregnant and non-pregnant goats daily throughout both pregnancies. Both pregnant and non-pregnant goats ate modest amounts of the plants with toxins and of beet pulp with LiCl. Both groups limited intake of novel foods and beet pulp with LiCl to the same degree. Finally, pregnant and non-pregnant goats did not differ in intake (per kg MBW) of the basal ration—dry matter, energy, or protein—in either pregnancy. Thus, the data do not support the notion that goats experienced pregnancy-related changes in food selection or intake.