Promoting the use of home-mixed supplements as alternatives to commercial supplements in smallholder beef production systems in the subhumid region of Zimbabwe

Abstract

The economic and performance effect of supplementing smallholder cattle by substituting commercial feed with iso-nitrogenous and iso-energetic diets based on alternative protein sources was investigated in two trials. In trial 1, three diets (commercial concentrate, commercial concentrate partially substituted with mucuna, and commercial concentrate partially substituted with lablab-cowpea) compared with veld grass were allocated to 12 cattle in a complete randomised block design. In trial 2, a double complete randomised block design with 40 cattle assigned to four forage legume-based diets, a poultry-based diet and a commercial beef concentrate was carried out. Diets were offered at 1.5% of body weight daily over 56 d. Average daily weight gain (ADWG) was measured weekly in trial 1 and fortnightly in trial 2. In trial 1, ADWG was significantly (p < 0.05) higher for animals on supplements compared with non-supplemented cattle. In trial 2, ADWG was significantly highest on the groundnut stover-based diet and least on the poultry litter diet. Supplementation had a positive effect on ADWG and economic performance of smallholder beef cattle. Substitution of commercial concentrates with alternative protein sources reduced diet costs and significantly improved gross margins.

Forage and maize yields in mixed crop-livestock farming systems

“…The greater LER of the intercrops could have been due to a greater resource use such as light, nutrients and water (Dahmardeh et al, 2010). Assuming the farmer feeds cattle at 5 kg per day/animal (Chakoma et al, 2016) and has five cattle (Mutenje et al, 2014), 25 kg of feed are required for the five cattle. If the farmer harvests 4 600 kg of forage, enough feed is therefore available for 184 days (about six months).…”

“…From the sole cropping results, farmers can feed their livestock for about four months but the feed is less nutritious as there is less protein from maize stover only compared to a mixture of maize and legume stover from intercrop systems (Jiri, 2003). Livestock feed from intercrops have additional crude protein from the legumes (Chakoma et al, 2016;Gwiriri et al, 2016;Descheemaeker et al, 2018). Dahmardeh et al (2010) showed that maize and cowpea intercrops gave higher total forage dry matter digestibility than maize or cowpea sole crops and led to increased feed quality (crude protein and dry matter digestibility concentration).…”

“…Consequently, the nutritious livestock feed will then result in manure of high quality (Murwira and Kirchmann, 1993) thereby improving soil fertility (Mugwira and Murwira, 1997;Waddington et al, 1998). Since most smallholder farmers are resource constrained (Mutenje et al, 2014), nutritious livestock feed from maize-legume intercropping systems will reduce the need for farmers to buy commercial feed concentrates (Chakoma et al, 2016).…”

“…Due to its high forage production rate, mucuna is increasingly becoming a viable option to supply supplementary feed for the smallholder farmers' livestock (Gwiriri et al, 2016). Feeding livestock with forage legumes reduces the cost of producing milk and increases income by 50 % compared to where commercial feeds are used (Murungweni et al, 2004;Chakoma et al, 2016;Gwiriri et al, 2016). Forage legumes increase the viability and availability of quality supplements during the dry months of the year, which usually coincides with poor feed quantity and quality (Gwiriri et al, 2016;Descheemaeker et al, 2018).…”

“…The various forage legumes and plant parts contain different crude protein levels. For example, mucuna plant (13.9 %), mucuna seed (21 %), soybean plant (30 %), cowpea plant (14 %) and groundnuts plant (14 %) compared to maize dry stover with 3.7 % (Chakoma et al, 2016;Gwiriri et al, 2016).…”