Fodder yield and nutritive quality of haulm from dual-purpose cowpea cultivars for dry season livestock feeding in Nigeria
The availability of high quality forage, especially during the dry season remains a major challenge to ruminant livestock production in Nigeria and many parts of West Africa. This study was conducted to evaluate forage yield and nutritive quality of haulm from selected dual purpose cowpea (Vigna unguiculata L. Walp.) cultivars in the humid rain forest zone of Nigeria. The forage and pod yields of twenty cultivars were evaluated at the Teaching and Research Farm of the Federal University of Technology, Owerri, Imo State, Nigeria. Subsequently, five dual-purpose cultivars, namely IT04K-334-2, IT07K-293-3, IT04K-194-3, IT04K-405-5, IT06K-147-2, were selected based on forage and pod yields from previous trial, for determination of chemical and fibre compositions. The results revealed significant (P<0.05) differences in pod and forage yields among the twenty cowpea cultivars, with yields ranging from 0-1.5 t ha-1 and 0.1-4.5 t ha-1 for pod and forage, respectively. Cultivars IT07K-293-3, IT04K-405-5, IT06K-147-2, IT07K-194-3, IT04K-334-2, IT04K-267-8 and IT04K-339-1 recorded the highest fodder yields of at least 2715 t ha-1, with crude protein contents ranging from 10.49% in IT07K-194-3 to 13 .57 % in IT04K-405-5. Cultivars IT07K-194-3, IT07K-293-3, IT07K-220-1-9, IT06K-147-2, IT07K-187-55IT04K-332-1 recorded the highest pod yields (>700 t ha-1). There were significant (P<0.05) differences in crude protein, ether extract and non-fibre carbohydrates (NFC) contents among five cultivars selected from the top ten high yielding cultivars, based on mean ranking score. These selected cultivars are recommended as dual-purpose cowpea for the humid forest zone.