Intake of Spineless Cladodes of Opuntia ficus-indica During Late Pregnancy Improves Progeny Performance in Underfed Sheep

SIMPLE SUMMARY: Plants in the Opuntia genus are abundant and can be used as a feed supplement because they are highly digestible and can provide water and energy. We fed sheep during late gestation with alfalfa (Control), Opuntia (Opuntia) or protein-enriched Opuntia (E-Opuntia) and measured milk yield and postnatal growth in the progeny. Birth weight did not differ among treatments (p > 0.05) but progeny from E-Opuntia grew faster (p < 0.01) and were heavier at weaning (p < 0.05), despite the fact that Control ewes produced more milk (p < 0.05). Feeding ewes with Opuntia (protein enriched or not) during the last third of gestation is an option for reducing production costs in underfed females managed under extensive conditions in arid and semiarid regions. ABSTRACT: The present study tested whether feeding ewes during the last third of pregnancy with cladodes of Opuntia (untreated or protein-enriched), as an alternative to alfalfa hay, would improve milk yield as well as the pre- and post-natal growth of their lambs. Sixty mature Rambouillet ewes and their progeny were randomly allocated among three nutritional treatments: (i) Control, fed alfalfa; (ii) Opuntia, fed untreated cladodes; (iii) E-Opuntia, fed protein-enriched cladodes (pre-treated with urea and ammonium sulphate). Birth weight did not differ among treatments (p > 0.05) but Control ewes produced more milk than both groups of Opuntia-fed ewes (p < 0.05). However, milk yield was not related to the growth of the progeny (p > 0.05) because lambs from E-Opuntia-fed ewes grew faster (p < 0.01) and were heavier at weaning (p < 0.05) than lambs from the other two groups. We conclude that Opuntia (with or without protein enrichment) can be used as an alternative to alfalfa hay for feeding ewes during the last third of pregnancy and therefore reduce production costs under extensive conditions in arid and semiarid regions. Moreover, protein-enriched Opuntia appears to improve postnatal lamb growth.