Abstract:
Smallholder dairy farms are increasingly being rediscovered as a strategy for improving livelihood to access diversify of food, employment as well as cash income. However, poor feeds remain a big challenge to dairy cattle productivity. While cereal crop residues have been reported as abundant in the Lake Victoria Crescent Agro-ecological zone (LVZ), their utilization by ruminants was still limited. In this research, production characteristics of smallholder dairy farmers, prioritization of available feed resources and optimization of on farm conditions for biological treatment of maize stover were evaluated. One hundred twenty six (126) smallholder dairy farmers were randomly sampled using multi-step simple random procedures. Focus group discussions, structured and semi-structured questionnaires so as to understand production characteristics of dairy farmers, temporal and special availability of alternative feed recourses. In a completely randomised block design, four popular edible Pleurotus fungal species namely; Pleurotus florida, Pleurotus ostreatus, Pleurotus sajor caju and Pleurotus pulmonarius were subjected to varying temperatures, pH levels, hydrogen peroxide (H2O2) concentrations .and illumination. Effects of pre-treatment methods of maize stover before solid-state fermentation with P. sajor caju including steaming (SMs), soaking in a molasses solution (114 g/kgDM) for 48 h (MMs), soaking in Lactobacillus plantarum (L. plantarum') (IO5 cfu/mL) inoculum for 48 h (LMs) and soaking in a mixture of molasses (114 g/kgDM) with L. plantarum (105 cfu/mL) for 48 h (MLMs) were examined using in vitro and in vivo methods. Using in vitro methods, maize stover pre-treatments were compared on in vitro gas production characteristics. Furthermore, a 4 x 4 Latin square design experiment with four primiporous Holstein-Friesian lactating cows with average body weight of 450 ± 20 kg and in early lactation (60 ± 10 day in milk (DIM)) were subjected to in vivo evaluation of pre-treated maize stover (SMs, MMs, LMs and MLMs) based on total mixed ration. Maize stover was ranked as the major cereal crop residue, however, it required qualitative improvement on nutritional quality due to recalcitrance of lignin. Pre treatment of maize stover with consortia of Lactobacillus plantarum, molasses prior to inoculation with P. sajor caju (MLMs) resulted into maize stover substrate with the highest (P<0.05) CP (96.6 g/kg DM), IVDMD (752.3 g/kg DM), IVOMD (687.2 g/kg DM) and ME (10.2 MJ/kg DM). Although the maize stover based total mixed ration improved (P=0.03) milk production (23.7 kg/d) and butterfat concentration (44.3 g/kg), there was no significant change in milk fatty acids profile apart from Cl8 and poly unsaturated fatty acids. Therefore, using consortia of P. sajor caju, L. plantarum and molasses break the lignin barrier to enhance its nutritional quality for improved productivity on smallholder dairy farm.